Make fixes and improvements

- Invent iso8601us() for faster timestamps
- Improve --strace descriptions of sigset_t
- Rebuild the Landlock Make bootstrap binary
- Introduce MODE=sysv for non-Windows builds
- Permit OFD fcntl() locks under pledge(flock)
- redbean can now protect your kernel from ddos
- Have vfork() fallback to sys_fork() not fork()
- Change kmalloc() to not die when out of memory
- Improve documentation for some termios functions
- Rewrite putenv() and friends to conform to POSIX
- Fix linenoise + strace verbosity issue on Windows
- Fix regressions in our ability to show backtraces
- Change redbean SetHeader() to no-op if value is nil
- Improve fcntl() so SQLite locks work in non-WAL mode
- Remove some unnecessary work during fork() on Windows
- Create redbean-based SSL reverse proxy for IPv4 TurfWar
- Fix ape/apeinstall.sh warning when using non-bash shells
- Add ProgramTrustedIp(), and IsTrustedIp() APIs to redbean
- Support $PWD, $UID, $GID, and $EUID in command interpreter
- Introduce experimental JTqFpD APE prefix for non-Windows builds
- Invent blackhole daemon for firewalling IP addresses via UNIX named socket
- Add ProgramTokenBucket(), AcquireToken(), and CountTokens() APIs to redbean

ape/ape.S

@@ -112,7 +112,15 @@ cstr:	.endobj	cstr,globl,hidden		# ←for gdb readability
 //
 //	@param	dl is drive number
 //	@noreturn
-ape_mz:	.asciz	"MZqFpD='\n"		# Mark 'Zibo' Joseph Zbikowski
+ape_mz:
+#if SupportsWindows() || SupportsMetal()
+	.asciz	"MZqFpD='\n"		# Mark 'Zibo' Joseph Zbikowski
+#else
+//	Avoid virus scanner reputation damage when targeting System Five.
+//	WARNING: This prefix is experimental; it may be removed sometime.
+//	TODO(jart): Find another prefix that will work with BIOS loading.
+	.asciz	"JTqFpD='\n"		# Mark 'Zibo' Joseph Zbikowski
+#endif
 	.short	0x1000			# MZ: lowers upper bound load / 16
 	.short	0xf800			# MZ: roll greed on bss
 	.short	0			# MZ: lower bound on stack segment

ape/apeinstall.sh

@@ -1,6 +1,6 @@
 #!/bin/sh
 
-if [ $UID -eq 0 ]; then
+if [ "$(id -u)" -eq 0 ]; then
   SUDO=
 else
   SUDO=sudo
@@ -97,6 +97,8 @@ if [ x"$(uname -s)" = xLinux ]; then
   echo you may need to edit configs to persist across reboot >&2
   echo '$SUDO sh -c "echo '"'"':APE:M::MZqFpD::/usr/bin/ape:'"'"' >/proc/sys/fs/binfmt_misc/register"' >&2
   $SUDO sh -c "echo ':APE:M::MZqFpD::/usr/bin/ape:' >/proc/sys/fs/binfmt_misc/register" || exit
+  echo '$SUDO sh -c "echo '"'"':APE-sysv:M::JTqFpD::/usr/bin/ape:'"'"' >/proc/sys/fs/binfmt_misc/register"' >&2
+  $SUDO sh -c "echo ':APE-sysv:M::JTqFpD::/usr/bin/ape:' >/proc/sys/fs/binfmt_misc/register" || exit
   echo done >&2
 
   if [ x"$(cat /proc/sys/fs/binfmt_misc/status)" = xdisabled ]; then

ape/apeuninstall.sh

@@ -11,6 +11,7 @@ fi
   echo "APE Uninstaller intends to run"
   echo
   echo "    $SUDO sh -c 'echo -1 >/proc/sys/fs/binfmt_misc/APE'"
+  echo "    $SUDO sh -c 'echo -1 >/proc/sys/fs/binfmt_misc/APE-sysv'"
   echo "    $SUDO rm -f /usr/bin/ape ~/.ape o/tmp/.ape /tmp/.ape"
   echo
   echo "You may then use ape/apeinstall.sh to reinstall it"
@@ -21,4 +22,7 @@ set -ex
 if [ -f /proc/sys/fs/binfmt_misc/APE ]; then
   $SUDO sh -c 'echo -1 >/proc/sys/fs/binfmt_misc/APE' || exit
 fi
+if [ -f /proc/sys/fs/binfmt_misc/APE-sysv ]; then
+  $SUDO sh -c 'echo -1 >/proc/sys/fs/binfmt_misc/APE-sysv' || exit
+fi
 $SUDO rm -f /usr/bin/ape ~/.ape o/tmp/.ape o/tmp/ape /tmp/.ape /tmp/ape || exit

build/config.mk

@@ -29,7 +29,7 @@ endif
 #
 ifeq ($(MODE),fastbuild)
 CONFIG_CCFLAGS += $(BACKTRACES) $(FTRACE) -O
-CONFIG_CPPFLAGS += -DSYSDEBUG
+CONFIG_CPPFLAGS += -DSYSDEBUG -DDWARFLESS
 CONFIG_OFLAGS += -g0
 CONFIG_LDFLAGS += -S
 TARGET_ARCH ?= -msse3
@@ -125,6 +125,22 @@ TARGET_ARCH ?= -msse3
 OVERRIDE_CCFLAGS += -fno-pie
 endif
 
+# System Five Mode
+#
+#   - `make MODE=sysv`
+#   - Optimized
+#   - Backtraces
+#   - Debuggable
+#   - Syscall tracing
+#   - Function tracing
+#   - No Windows bloat!
+#
+ifeq ($(MODE), sysv)
+CONFIG_CCFLAGS += $(BACKTRACES) $(FTRACE) -O2
+CONFIG_CPPFLAGS += -DSYSDEBUG -DSUPPORT_VECTOR=121
+TARGET_ARCH ?= -msse3
+endif
+
 # Tiny Mode
 #
 #   - `make MODE=tiny`
@@ -151,7 +167,8 @@ CONFIG_CCFLAGS +=			\
 	-fschedule-insns2		\
 	-fomit-frame-pointer		\
 	-momit-leaf-frame-pointer	\
-	-foptimize-sibling-calls
+	-foptimize-sibling-calls	\
+	-DDWARFLESS
 CONFIG_OFLAGS +=			\
 	-g0
 CONFIG_LDFLAGS +=			\
@@ -181,7 +198,8 @@ CONFIG_CPPFLAGS +=			\
 	-DTINY				\
 	-DNDEBUG			\
 	-DTRUSTWORTHY			\
-	-DSUPPORT_VECTOR=1
+	-DSUPPORT_VECTOR=1		\
+	-DDWARFLESS
 DEFAULT_COPTS +=			\
 	-mred-zone
 CONFIG_OFLAGS +=			\
@@ -217,7 +235,8 @@ CONFIG_CPPFLAGS +=		\
 	-DTINY			\
 	-DNDEBUG		\
 	-DTRUSTWORTHY		\
-	-DSUPPORT_VECTOR=113
+	-DSUPPORT_VECTOR=113	\
+	-DDWARFLESS
 DEFAULT_COPTS +=		\
 	-mred-zone
 CONFIG_OFLAGS +=		\
@@ -252,7 +271,8 @@ CONFIG_CPPFLAGS +=		\
 	-DTINY			\
 	-DNDEBUG		\
 	-DTRUSTWORTHY		\
-	-DSUPPORT_VECTOR=121
+	-DSUPPORT_VECTOR=121	\
+	-DDWARFLESS
 DEFAULT_COPTS +=		\
 	-mred-zone
 CONFIG_CCFLAGS +=		\
@@ -287,7 +307,8 @@ CONFIG_CPPFLAGS +=		\
 	-DTINY			\
 	-DNDEBUG		\
 	-DTRUSTWORTHY		\
-	-DSUPPORT_VECTOR=251
+	-DSUPPORT_VECTOR=251	\
+	-DDWARFLESS
 CONFIG_CCFLAGS +=		\
 	-Os			\
 	-fno-align-functions	\

examples/auto-memory-safety-crash2.c

@@ -7,12 +7,12 @@
 │   • http://creativecommons.org/publicdomain/zero/1.0/            │
 ╚─────────────────────────────────────────────────────────────────*/
 #endif
-#include "libc/intrin/bits.h"
 #include "libc/dce.h"
+#include "libc/intrin/bits.h"
+#include "libc/intrin/kprintf.h"
 #include "libc/log/log.h"
 #include "libc/mem/mem.h"
 #include "libc/runtime/runtime.h"
-#include "libc/stdio/stdio.h"
 #include "libc/str/str.h"
 
 /**
@@ -59,9 +59,15 @@
 
 int main(int argc, char *argv[]) {
   if (!IsAsan()) {
-    printf("this example is intended for MODE=asan or MODE=dbg\n");
+    kprintf("this example is intended for MODE=asan or MODE=dbg\n");
     exit(1);
   }
+
+  kprintf("----------------\n");
+  kprintf(" THIS IS A TEST \n");
+  kprintf("SIMULATING CRASH\n");
+  kprintf("----------------\n");
+
   char *buffer;
   ShowCrashReports(); /* not needed but yoinks appropriate symbols */
   buffer = malloc(13);

examples/crashreport.c

@@ -7,6 +7,7 @@
 │   • http://creativecommons.org/publicdomain/zero/1.0/            │
 ╚─────────────────────────────────────────────────────────────────*/
 #endif
+#include "libc/intrin/kprintf.h"
 #include "libc/log/log.h"
 #include "libc/runtime/symbols.internal.h"
 
@@ -24,6 +25,12 @@
  */
 
 noubsan int main(int argc, char *argv[]) {
+
+  kprintf("----------------\n");
+  kprintf(" THIS IS A TEST \n");
+  kprintf("SIMULATING CRASH\n");
+  kprintf("----------------\n");
+
   volatile int64_t x;
   ShowCrashReports();
   return 1 / (x = 0);

examples/examples.mk

@@ -146,6 +146,25 @@ o/$(MODE)/examples/nesemu1.com.dbg:						\
 		$(EXAMPLES_BOOTLOADER)
 	@$(APELINK)
 
+# # force symtab.com to be a zip file, by pulling a zip asset into linkage
+# # we wouldn't need to do this if we depended on functions like localtime
+# o/$(MODE)/examples/symtab.com.dbg:						\
+# 		$(EXAMPLES_DEPS)						\
+# 		o/$(MODE)/examples/symtab.o					\
+# 		o/$(MODE)/examples/symtab.c.zip.o				\
+# 		o/$(MODE)/examples/examples.pkg					\
+# 		$(EXAMPLES_BOOTLOADER)
+# 	@$(APELINK)
+
+# modify .com so it can read the symbol table without needing the .com.dbg file
+o/$(MODE)/examples/symtab.com:							\
+		o/$(MODE)/examples/symtab.com.dbg				\
+		o/$(MODE)/third_party/zip/zip.com				\
+		o/$(MODE)/tool/build/symtab.com
+	@$(MAKE_OBJCOPY)
+	@$(MAKE_SYMTAB_CREATE)
+	@$(MAKE_SYMTAB_ZIP)
+
 o/$(MODE)/examples/picol.o: private				\
 		OVERRIDE_CPPFLAGS +=				\
 			-DSTACK_FRAME_UNLIMITED

examples/nesemu1.cc

@@ -47,7 +47,7 @@
 #include "third_party/libcxx/vector"
 #include "tool/viz/lib/knobs.h"
 
-STATIC_YOINK("zip_uri_support");
+STATIC_YOINK("zipos");
 
 #define USAGE \
   " [ROM] [FMV]\n\

examples/symtab.c

@@ -0,0 +1,42 @@
+#if 0
+/*─────────────────────────────────────────────────────────────────╗
+│ To the extent possible under law, Justine Tunney has waived      │
+│ all copyright and related or neighboring rights to this file,    │
+│ as it is written in the following disclaimers:                   │
+│   • http://unlicense.org/                                        │
+│   • http://creativecommons.org/publicdomain/zero/1.0/            │
+╚─────────────────────────────────────────────────────────────────*/
+#endif
+#include "libc/intrin/kprintf.h"
+#include "libc/log/log.h"
+
+/**
+ * @fileoverview example of how to embed symbol table in .com file
+ *
+ *     # build our binary
+ *     make -j16 o//examples/symtab.com
+ *
+ *     # move binary somewhere else
+ *     # so it can't find the .com.dbg binary
+ *     cp o//examples/symtab.com /tmp
+ *
+ *     # run program
+ *     # notice that it has a symbolic backtrace
+ *     /tmp/symtab.com
+ *
+ * @see examples/examples.mk
+ */
+
+int main(int argc, char *argv[]) {
+
+  // this links all the debugging and zip functionality
+  ShowCrashReports();
+
+  kprintf("----------------\n");
+  kprintf(" THIS IS A TEST \n");
+  kprintf("SIMULATING CRASH\n");
+  kprintf("----------------\n");
+
+  volatile int64_t x;
+  return 1 / (x = 0);
+}

libc/calls/__sig_mask.c

@@ -16,7 +16,9 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/assert.h"
 #include "libc/calls/sig.internal.h"
+#include "libc/calls/struct/sigset.h"
 #include "libc/sysv/consts/sig.h"
 #include "libc/sysv/errfuns.h"
 #include "libc/thread/tls.h"

libc/calls/blocksigs.internal.h

@@ -0,0 +1,19 @@
+#ifndef COSMOPOLITAN_LIBC_CALLS_BLOCKSIGS_INTERNAL_H_
+#define COSMOPOLITAN_LIBC_CALLS_BLOCKSIGS_INTERNAL_H_
+#include "libc/calls/struct/sigset.h"
+#if !(__ASSEMBLER__ + __LINKER__ + 0)
+COSMOPOLITAN_C_START_
+
+#define BLOCK_SIGNALS  \
+  do {                 \
+    sigset_t _SigMask; \
+  _SigMask = _sigblockall()
+
+#define ALLOW_SIGNALS    \
+  _sigsetmask(_SigMask); \
+  }                      \
+  while (0)
+
+COSMOPOLITAN_C_END_
+#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
+#endif /* COSMOPOLITAN_LIBC_CALLS_BLOCKSIGS_INTERNAL_H_ */

libc/calls/calls.h

@@ -65,13 +65,13 @@ char *ttyname(int);
 int access(const char *, int) dontthrow;
 int arch_prctl();
 int chdir(const char *);
-int chmod(const char *, uint32_t);
-int chown(const char *, uint32_t, uint32_t);
+int chmod(const char *, unsigned);
+int chown(const char *, unsigned, unsigned);
 int chroot(const char *);
 int close(int);
 int close_range(unsigned, unsigned, unsigned);
 int closefrom(int);
-int creat(const char *, uint32_t);
+int creat(const char *, unsigned);
 int dup(int);
 int dup2(int, int);
 int dup3(int, int, int);
@@ -84,25 +84,22 @@ int execv(const char *, char *const[]);
 int execve(const char *, char *const[], char *const[]);
 int execvp(const char *, char *const[]);
 int execvpe(const char *, char *const[], char *const[]);
-int fexecve(int, char *const[], char *const[]);
 int faccessat(int, const char *, int, int);
 int fadvise(int, uint64_t, uint64_t, int);
 int fchdir(int);
-int fchmod(int, uint32_t) dontthrow;
-int fchmodat(int, const char *, uint32_t, int);
-int fchown(int, uint32_t, uint32_t);
-int fchownat(int, const char *, uint32_t, uint32_t, int);
+int fchmod(int, unsigned) dontthrow;
+int fchmodat(int, const char *, unsigned, int);
+int fchown(int, unsigned, unsigned);
+int fchownat(int, const char *, unsigned, unsigned, int);
 int fcntl(int, int, ...);
 int fdatasync(int);
+int fexecve(int, char *const[], char *const[]);
 int flock(int, int);
 int fork(void);
 int fsync(int);
 int ftruncate(int, int64_t);
 int getdomainname(char *, size_t);
-uint32_t getegid(void) nosideeffect;
-uint32_t geteuid(void) nosideeffect;
-uint32_t getgid(void) nosideeffect;
-int getgroups(int size, uint32_t list[]);
+int getgroups(int, unsigned[]);
 int gethostname(char *, size_t);
 int getloadavg(double *, int);
 int getpgid(int) libcesque;
@@ -110,36 +107,29 @@ int getpgrp(void) nosideeffect;
 int getpid(void) nosideeffect libcesque;
 int getppid(void);
 int getpriority(int, unsigned);
-int getresgid(uint32_t *, uint32_t *, uint32_t *);
-int getresuid(uint32_t *, uint32_t *, uint32_t *);
+int getresgid(unsigned *, unsigned *, unsigned *);
+int getresuid(unsigned *, unsigned *, unsigned *);
 int getsid(int) nosideeffect libcesque;
 int gettid(void) libcesque;
-uint32_t getuid(void) libcesque;
-int sys_iopl(int);
 int ioprio_get(int, int);
 int ioprio_set(int, int, int);
 int issetugid(void);
 int kill(int, int);
 int killpg(int, int);
-int lchmod(const char *, uint32_t);
-int lchown(const char *, uint32_t, uint32_t);
+int lchmod(const char *, unsigned);
+int lchown(const char *, unsigned, unsigned);
 int link(const char *, const char *) dontthrow;
 int linkat(int, const char *, int, const char *, int);
 int madvise(void *, uint64_t, int);
+int makedirs(const char *, unsigned);
 int memfd_create(const char *, unsigned int);
 int mincore(void *, size_t, unsigned char *);
 int mkdir(const char *, unsigned);
 int mkdirat(int, const char *, unsigned);
-int makedirs(const char *, unsigned);
-int mkfifo(const char *, uint32_t);
-int mkfifoat(int, const char *, uint32_t);
-int mknod(const char *, uint32_t, uint64_t);
-int mknodat(int, const char *, int32_t, uint64_t);
-int sys_mlock(const void *, size_t);
-int sys_mlock2(const void *, size_t, int);
-int sys_mlockall(int);
-int sys_munlock(const void *, size_t);
-int sys_munlockall(void);
+int mkfifo(const char *, unsigned);
+int mkfifoat(int, const char *, unsigned);
+int mknod(const char *, unsigned, uint64_t);
+int mknodat(int, const char *, int, uint64_t);
 int nice(int);
 int open(const char *, int, ...);
 int openat(int, const char *, int, ...);
@@ -161,19 +151,19 @@ int renameat2(long, const char *, long, const char *, int);
 int rmdir(const char *);
 int sched_yield(void);
 int seccomp(unsigned, unsigned, void *);
-int setegid(uint32_t);
-int seteuid(uint32_t);
+int setegid(unsigned);
+int seteuid(unsigned);
 int setfsgid(unsigned);
 int setfsuid(unsigned);
 int setgid(unsigned);
-int setgroups(size_t, const uint32_t[]);
+int setgroups(size_t, const unsigned[]);
 int setpgid(int, int);
 int setpgrp(void);
 int setpriority(int, unsigned, int);
-int setregid(uint32_t, uint32_t);
-int setresgid(uint32_t, uint32_t, uint32_t);
-int setresuid(uint32_t, uint32_t, uint32_t);
-int setreuid(uint32_t, uint32_t);
+int setregid(unsigned, unsigned);
+int setresgid(unsigned, unsigned, unsigned);
+int setresuid(unsigned, unsigned, unsigned);
+int setreuid(unsigned, unsigned);
 int setsid(void);
 int setuid(unsigned);
 int sigignore(int);
@@ -181,16 +171,22 @@ int siginterrupt(int, int);
 int symlink(const char *, const char *);
 int symlinkat(const char *, int, const char *);
 int sync_file_range(int, int64_t, int64_t, unsigned);
+int sys_iopl(int);
+int sys_mlock(const void *, size_t);
+int sys_mlock2(const void *, size_t, int);
+int sys_mlockall(int);
+int sys_munlock(const void *, size_t);
+int sys_munlockall(void);
 int sys_ptrace(int, ...);
 int sys_sysctl(const int *, unsigned, void *, size_t *, void *, size_t);
-int tcsetpgrp(int, int32_t);
+int tcgetpgrp(int);
+int tcsetpgrp(int, int);
 int tgkill(int, int, int);
 int tkill(int, int);
 int tmpfd(void);
-int touch(const char *, uint32_t);
+int touch(const char *, unsigned);
 int truncate(const char *, int64_t);
 int ttyname_r(int, char *, size_t);
-unsigned umask(unsigned);
 int unlink(const char *);
 int unlink_s(const char **);
 int unlinkat(int, const char *, int);
@@ -199,11 +195,10 @@ int usleep(unsigned);
 int vfork(void) returnstwice;
 int wait(int *);
 int waitpid(int, int *, int);
-int32_t tcgetpgrp(int);
 intptr_t syscall(int, ...);
 long ptrace(int, ...);
-ssize_t copy_file_range(int, long *, int, long *, size_t, uint32_t);
-ssize_t copyfd(int, int64_t *, int, int64_t *, size_t, uint32_t);
+ssize_t copy_file_range(int, long *, int, long *, size_t, unsigned);
+ssize_t copyfd(int, int64_t *, int, int64_t *, size_t, unsigned);
 ssize_t getfiledescriptorsize(int);
 ssize_t lseek(int, int64_t, int);
 ssize_t pread(int, void *, size_t, int64_t);
@@ -212,8 +207,13 @@ ssize_t read(int, void *, size_t);
 ssize_t readansi(int, char *, size_t);
 ssize_t readlink(const char *, char *, size_t);
 ssize_t readlinkat(int, const char *, char *, size_t);
-ssize_t splice(int, int64_t *, int, int64_t *, size_t, uint32_t);
+ssize_t splice(int, int64_t *, int, int64_t *, size_t, unsigned);
 ssize_t write(int, const void *, size_t);
+unsigned getegid(void) nosideeffect;
+unsigned geteuid(void) nosideeffect;
+unsigned getgid(void) nosideeffect;
+unsigned getuid(void) libcesque;
+unsigned umask(unsigned);
 void sync(void);
 
 COSMOPOLITAN_C_END_

libc/calls/cfspeed.c

@@ -0,0 +1,88 @@
+/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
+│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
+╞══════════════════════════════════════════════════════════════════════════════╡
+│ Copyright 2021 Justine Alexandra Roberts Tunney                              │
+│                                                                              │
+│ Permission to use, copy, modify, and/or distribute this software for         │
+│ any purpose with or without fee is hereby granted, provided that the         │
+│ above copyright notice and this permission notice appear in all copies.      │
+│                                                                              │
+│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
+│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
+│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
+│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
+│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
+│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
+│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
+│ PERFORMANCE OF THIS SOFTWARE.                                                │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/calls/termios.h"
+#include "libc/sysv/consts/termios.h"
+#include "libc/sysv/errfuns.h"
+
+/**
+ * Returns input baud rate.
+ * @asyncsignalsafe
+ */
+uint32_t cfgetispeed(const struct termios *t) {
+  if (CBAUD) {
+    return t->c_cflag & CBAUD;
+  } else {
+    return t->c_ispeed;
+  }
+}
+
+/**
+ * Returns output baud rate.
+ * @asyncsignalsafe
+ */
+uint32_t cfgetospeed(const struct termios *t) {
+  if (CBAUD) {
+    return t->c_cflag & CBAUD;
+  } else {
+    return t->c_ospeed;
+  }
+}
+
+/**
+ * Sets input baud rate.
+ *
+ * @return 0 on success, or -1 w/ errno
+ * @asyncsignalsafe
+ */
+int cfsetispeed(struct termios *t, unsigned speed) {
+  if (speed) {
+    if (CBAUD) {
+      if (!(speed & ~CBAUD)) {
+        t->c_cflag &= ~CBAUD;
+        t->c_cflag |= speed;
+      } else {
+        return einval();
+      }
+    } else {
+      t->c_ispeed = speed;
+    }
+  }
+  return 0;
+}
+
+/**
+ * Sets output baud rate.
+ *
+ * @return 0 on success, or -1 w/ errno
+ * @asyncsignalsafe
+ */
+int cfsetospeed(struct termios *t, unsigned speed) {
+  if (CBAUD) {
+    if (!(speed & ~CBAUD)) {
+      t->c_cflag &= ~CBAUD;
+      t->c_cflag |= speed;
+      return 0;
+    } else {
+      return einval();
+    }
+  } else {
+    t->c_ospeed = speed;
+    return 0;
+  }
+}

libc/calls/close-nt.c

@@ -18,15 +18,22 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/struct/fd.internal.h"
 #include "libc/errno.h"
+#include "libc/intrin/weaken.h"
 #include "libc/nt/enum/filetype.h"
 #include "libc/nt/files.h"
 #include "libc/nt/runtime.h"
 #include "libc/sysv/consts/o.h"
 
-textwindows int sys_close_nt(struct Fd *fd) {
+void sys_fcntl_nt_lock_cleanup(int) hidden;
+
+textwindows int sys_close_nt(struct Fd *fd, int fildes) {
   int e;
   bool ok = true;
 
+  if (_weaken(sys_fcntl_nt_lock_cleanup)) {
+    _weaken(sys_fcntl_nt_lock_cleanup)(fildes);
+  }
+
   if (fd->kind == kFdFile && ((fd->flags & O_ACCMODE) != O_RDONLY &&
                               GetFileType(fd->handle) == kNtFileTypeDisk)) {
     // Like Linux, closing a file on Windows doesn't guarantee it's

libc/calls/close.c

@@ -16,10 +16,10 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/assert.h"
 #include "libc/calls/calls.h"
 #include "libc/calls/internal.h"
 #include "libc/calls/state.internal.h"
+#include "libc/calls/struct/fd.internal.h"
 #include "libc/calls/syscall-nt.internal.h"
 #include "libc/calls/syscall-sysv.internal.h"
 #include "libc/dce.h"
@@ -81,7 +81,7 @@ int close(int fd) {
         } else if (__isfdkind(fd, kFdFile) ||     //
                    __isfdkind(fd, kFdConsole) ||  //
                    __isfdkind(fd, kFdProcess)) {  //
-          rc = sys_close_nt(g_fds.p + fd);
+          rc = sys_close_nt(g_fds.p + fd, fd);
         } else {
           rc = eio();
         }

libc/calls/closefrom.c

@@ -27,12 +27,9 @@
 /**
  * Closes extra file descriptors, e.g.
  *
- *     // close all non-stdio file descriptors
- *     if (closefrom(3) == -1) {
- *       for (int i = 3; i < 256; ++i) {
+ *     if (closefrom(3))
+ *       for (int i = 3; i < 256; ++i)
  *         close(i);
- *       }
- *     }
  *
  * @return 0 on success, or -1 w/ errno
  * @raise EBADF if `first` is negative

libc/calls/dup-nt.c

@@ -45,27 +45,18 @@ textwindows int sys_dup_nt(int oldfd, int newfd, int flags, int start) {
   }
 
   // allocate a new file descriptor
-  for (;;) {
-    if (newfd == -1) {
-      if ((newfd = __reservefd_unlocked(start)) == -1) {
-        __fds_unlock();
-        return -1;
-      }
-      break;
-    } else {
-      if (__ensurefds_unlocked(newfd) == -1) {
-        __fds_unlock();
-        return -1;
-      }
-      if (g_fds.p[newfd].kind) {
-        __fds_unlock();
-        close(newfd);
-        __fds_lock();
-      }
-      if (!g_fds.p[newfd].kind) {
-        g_fds.p[newfd].kind = kFdReserved;
-        break;
-      }
+  if (newfd == -1) {
+    if ((newfd = __reservefd_unlocked(start)) == -1) {
+      __fds_unlock();
+      return -1;
+    }
+  } else {
+    if (__ensurefds_unlocked(newfd) == -1) {
+      __fds_unlock();
+      return -1;
+    }
+    if (g_fds.p[newfd].kind) {
+      sys_close_nt(g_fds.p + newfd, newfd);
     }
   }
 
@@ -86,7 +77,7 @@ textwindows int sys_dup_nt(int oldfd, int newfd, int flags, int start) {
     }
     rc = newfd;
   } else {
-    __releasefd_unlocked(newfd);
+    __releasefd(newfd);
     rc = __winerr();
   }
 

libc/calls/execve-sysv.c

@@ -16,6 +16,7 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/calls/blocksigs.internal.h"
 #include "libc/calls/calls.h"
 #include "libc/calls/syscall-sysv.internal.h"
 #include "libc/dce.h"
@@ -40,7 +41,9 @@ static bool IsApeBinary(const char *path) {
   char buf[8];
   bool res = false;
   if ((fd = sys_open(path, O_RDONLY, 0)) != -1) {
-    if (sys_read(fd, buf, 8) == 8 && READ64LE(buf) == READ64LE("MZqFpD='")) {
+    if (sys_read(fd, buf, 8) == 8 &&  //
+        (READ64LE(buf) == READ64LE("MZqFpD='") ||
+         READ64LE(buf) == READ64LE("JTqFpD='"))) {
       res = true;
     }
     sys_close(fd);
@@ -61,35 +64,41 @@ static const char *Join(const char *a, const char *b, char buf[PATH_MAX]) {
 }
 
 int sys_execve(const char *prog, char *const argv[], char *const envp[]) {
-  int e;
   size_t i;
+  int e, rc;
   char *buf;
   char **shargs;
   const char *ape;
   e = errno;
   __sys_execve(prog, argv, envp);
-  if (errno != ENOEXEC) return -1;
-  for (i = 0; argv[i];) ++i;
-  buf = alloca(PATH_MAX);
-  shargs = alloca((i + 4) * sizeof(char *));
-  if (IsApeBinary(prog) &&
-      (CanExecute((ape = "/usr/bin/ape")) ||
-       CanExecute((ape = Join(firstnonnull(getenv("TMPDIR"),
-                                           firstnonnull(getenv("HOME"), ".")),
-                              ".ape", buf))) ||
-       CanExecute(
-           (ape = Join(firstnonnull(getenv("HOME"), "."), ".ape", buf))))) {
-    shargs[0] = ape;
-    shargs[1] = "-";
-    shargs[2] = prog;
-    memcpy(shargs + 3, argv, (i + 1) * sizeof(char *));
-  } else if (CanExecute(prog)) {
-    shargs[0] = _PATH_BSHELL;
-    shargs[1] = prog;
-    memcpy(shargs + 2, argv + 1, i * sizeof(char *));
+  if (errno == ENOEXEC) {
+    for (i = 0; argv[i];) ++i;
+    buf = alloca(PATH_MAX);
+    shargs = alloca((i + 4) * sizeof(char *));
+    if (IsApeBinary(prog) &&
+        (CanExecute((ape = "/usr/bin/ape")) ||
+         CanExecute((ape = Join(firstnonnull(getenv("TMPDIR"),
+                                             firstnonnull(getenv("HOME"), ".")),
+                                ".ape", buf))) ||
+         CanExecute(
+             (ape = Join(firstnonnull(getenv("HOME"), "."), ".ape", buf))))) {
+      shargs[0] = ape;
+      shargs[1] = "-";
+      shargs[2] = prog;
+      memcpy(shargs + 3, argv, (i + 1) * sizeof(char *));
+      errno = e;
+      rc = __sys_execve(shargs[0], shargs, envp);
+    } else if (CanExecute(prog)) {
+      shargs[0] = _PATH_BSHELL;
+      shargs[1] = prog;
+      memcpy(shargs + 2, argv + 1, i * sizeof(char *));
+      errno = e;
+      rc = __sys_execve(shargs[0], shargs, envp);
+    } else {
+      rc = enoexec();
+    }
   } else {
-    return enoexec();
+    rc = -1;
   }
-  errno = e;
-  return __sys_execve(shargs[0], shargs, envp);
+  return rc;
 }

libc/calls/execve.c

@@ -54,9 +54,9 @@ int execve(const char *prog, char *const argv[], char *const envp[]) {
   int rc;
   size_t i;
   if (!prog || !argv || !envp ||
-      (IsAsan() &&
-       (!__asan_is_valid(prog, 1) || !__asan_is_valid_strlist(argv) ||
-        !__asan_is_valid_strlist(envp)))) {
+      (IsAsan() && (!__asan_is_valid(prog, 1) ||       //
+                    !__asan_is_valid_strlist(argv) ||  //
+                    !__asan_is_valid_strlist(envp)))) {
     rc = efault();
   } else {
     STRACE("execve(%#s, %s, %s) → ...", prog, DescribeStringList(argv),

libc/calls/fcntl-nt.c

@@ -16,6 +16,7 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/assert.h"
 #include "libc/calls/calls.h"
 #include "libc/calls/internal.h"
 #include "libc/calls/struct/fd.internal.h"
@@ -24,63 +25,131 @@
 #include "libc/calls/syscall_support-nt.internal.h"
 #include "libc/calls/wincrash.internal.h"
 #include "libc/errno.h"
+#include "libc/intrin/kmalloc.h"
 #include "libc/intrin/weaken.h"
+#include "libc/limits.h"
 #include "libc/log/backtrace.internal.h"
+#include "libc/macros.internal.h"
 #include "libc/nt/enum/filelockflags.h"
 #include "libc/nt/errors.h"
 #include "libc/nt/files.h"
 #include "libc/nt/runtime.h"
 #include "libc/nt/struct/byhandlefileinformation.h"
 #include "libc/nt/struct/overlapped.h"
+#include "libc/str/str.h"
 #include "libc/sysv/consts/f.h"
 #include "libc/sysv/consts/fd.h"
 #include "libc/sysv/consts/o.h"
 #include "libc/sysv/errfuns.h"
+#include "libc/thread/thread.h"
 
-static textwindows int sys_fcntl_nt_dupfd(int fd, int cmd, int start) {
-  if (start < 0) return einval();
-  return sys_dup_nt(fd, -1, (cmd == F_DUPFD_CLOEXEC ? O_CLOEXEC : 0), start);
+struct FileLock {
+  struct FileLock *next;
+  int64_t off;
+  int64_t len;
+  int fd;
+  bool exc;
+};
+
+struct FileLocks {
+  pthread_mutex_t mu;
+  struct FileLock *list;
+  struct FileLock *free;
+};
+
+static struct FileLocks g_locks;
+
+static textwindows struct FileLock *NewFileLock(void) {
+  struct FileLock *fl;
+  if (g_locks.free) {
+    fl = g_locks.free;
+    g_locks.free = fl->next;
+  } else {
+    fl = kmalloc(sizeof(*fl));
+  }
+  bzero(fl, sizeof(*fl));
+  fl->next = g_locks.list;
+  g_locks.list = fl;
+  return fl;
 }
 
-static textwindows int sys_fcntl_nt_lock(struct Fd *f, int cmd, uintptr_t arg) {
+static textwindows void FreeFileLock(struct FileLock *fl) {
+  fl->next = g_locks.free;
+  g_locks.free = fl;
+}
+
+static textwindows bool OverlapsFileLock(struct FileLock *fl, int64_t off,
+                                         int64_t len) {
+  uint64_t BegA, EndA, BegB, EndB;
+  BegA = off;
+  EndA = off + (len - 1);
+  BegB = fl->off;
+  EndB = fl->off + (fl->len - 1);
+  return MAX(BegA, BegB) < MIN(EndA, EndB);
+}
+
+static textwindows bool EncompassesFileLock(struct FileLock *fl, int64_t off,
+                                            int64_t len) {
+  return off <= fl->off && fl->off + fl->len <= off + len;
+}
+
+static textwindows bool EqualsFileLock(struct FileLock *fl, int64_t off,
+                                       int64_t len) {
+  return fl->off == off && off + len == fl->off + fl->len;
+}
+
+hidden textwindows void sys_fcntl_nt_lock_cleanup(int fd) {
+  struct FileLock *fl, *ft, **flp;
+  pthread_mutex_lock(&g_locks.mu);
+  for (flp = &g_locks.list, fl = *flp; fl;) {
+    if (fl->fd == fd) {
+      *flp = fl->next;
+      ft = fl->next;
+      FreeFileLock(fl);
+      fl = ft;
+    } else {
+      flp = &fl->next;
+      fl = *flp;
+    }
+  }
+  pthread_mutex_unlock(&g_locks.mu);
+}
+
+static textwindows int sys_fcntl_nt_lock(struct Fd *f, int fd, int cmd,
+                                         uintptr_t arg) {
   int e;
   struct flock *l;
   uint32_t flags, err;
-  int64_t pos, off, len, size;
-  struct NtByHandleFileInformation info;
-
-  if (!GetFileInformationByHandle(f->handle, &info)) {
-    return __winerr();
-  }
-
-  pos = 0;
-  if (!SetFilePointerEx(f->handle, 0, &pos, SEEK_CUR)) {
-    return __winerr();
-  }
+  struct FileLock *fl, *ft, **flp;
+  int64_t pos, off, len, end, size;
 
   l = (struct flock *)arg;
   len = l->l_len;
   off = l->l_start;
-  size = (uint64_t)info.nFileSizeHigh << 32 | info.nFileSizeLow;
 
   switch (l->l_whence) {
     case SEEK_SET:
       break;
     case SEEK_CUR:
-      off = pos + off;
+      pos = 0;
+      if (SetFilePointerEx(f->handle, 0, &pos, SEEK_CUR)) {
+        off = pos + off;
+      } else {
+        return __winerr();
+      }
       break;
     case SEEK_END:
-      off = size - off;
+      off = INT64_MAX - off;
       break;
     default:
       return einval();
   }
 
   if (!len) {
-    len = size - off;
+    len = INT64_MAX - off;
   }
 
-  if (off < 0 || len < 0) {
+  if (off < 0 || len < 0 || __builtin_add_overflow(off, len, &end)) {
     return einval();
   }
 
@@ -89,8 +158,57 @@ static textwindows int sys_fcntl_nt_lock(struct Fd *f, int cmd, uintptr_t arg) {
                             .Pointer = (void *)(uintptr_t)off};
 
   if (l->l_type == F_RDLCK || l->l_type == F_WRLCK) {
+
+    if (cmd == F_SETLK || cmd == F_SETLKW) {
+      // make it possible to transition read locks to write locks
+      for (flp = &g_locks.list, fl = *flp; fl;) {
+        if (fl->fd == fd) {
+          if (EqualsFileLock(fl, off, len)) {
+            if (fl->exc == l->l_type == F_WRLCK) {
+              // we already have this lock
+              return 0;
+            } else {
+              // unlock our read lock and acquire write lock below
+              if (UnlockFileEx(f->handle, 0, len, len >> 32, &ov)) {
+                *flp = fl->next;
+                ft = fl->next;
+                FreeFileLock(fl);
+                fl = ft;
+                continue;
+              } else {
+                return -1;
+              }
+            }
+            break;
+          } else if (OverlapsFileLock(fl, off, len)) {
+            return enotsup();
+          }
+        }
+        flp = &fl->next;
+        fl = *flp;
+      }
+    }
+
+    // return better information on conflicting locks if possible
+    if (cmd == F_GETLK) {
+      for (fl = g_locks.list; fl; fl = fl->next) {
+        if (fl->fd == fd &&  //
+            OverlapsFileLock(fl, off, len) &&
+            (l->l_type == F_WRLCK || !fl->exc)) {
+          l->l_whence = SEEK_SET;
+          l->l_start = fl->off;
+          l->l_len = fl->len;
+          l->l_type == fl->exc ? F_WRLCK : F_RDLCK;
+          l->l_pid = getpid();
+          return 0;
+        }
+      }
+    }
+
     flags = 0;
     if (cmd != F_SETLKW) {
+      // TODO(jart): we should use expo backoff in wrapper function
+      //             should not matter since sqlite doesn't need it
       flags |= kNtLockfileFailImmediately;
     }
     if (l->l_type == F_WRLCK) {
@@ -101,68 +219,133 @@ static textwindows int sys_fcntl_nt_lock(struct Fd *f, int cmd, uintptr_t arg) {
       if (ok) {
         l->l_type = F_UNLCK;
         if (!UnlockFileEx(f->handle, 0, len, len >> 32, &ov)) {
-          notpossible;
+          return -1;
         }
       } else {
         l->l_pid = -1;
         ok = true;
       }
+    } else if (ok) {
+      fl = NewFileLock();
+      fl->off = off;
+      fl->len = len;
+      fl->exc = l->l_type == F_WRLCK;
+      fl->fd = fd;
     }
     return ok ? 0 : -1;
   }
 
   if (l->l_type == F_UNLCK) {
     if (cmd == F_GETLK) return einval();
-    e = errno;
-    if (UnlockFileEx(f->handle, 0, len, len >> 32, &ov)) {
-      return 0;
-    } else if (errno == ENOLCK) {
-      errno = e;
-      return 0;
-    } else {
-      return 0;
+
+    // allow a big range to unlock many small ranges
+    for (flp = &g_locks.list, fl = *flp; fl;) {
+      if (fl->fd == fd && EncompassesFileLock(fl, off, len)) {
+        struct NtOverlapped ov = {.hEvent = f->handle,
+                                  .Pointer = (void *)(uintptr_t)fl->off};
+        if (UnlockFileEx(f->handle, 0, fl->len, fl->len >> 32, &ov)) {
+          *flp = fl->next;
+          ft = fl->next;
+          FreeFileLock(fl);
+          fl = ft;
+        } else {
+          return -1;
+        }
+      } else {
+        flp = &fl->next;
+        fl = *flp;
+      }
     }
+
+    // win32 won't let us carve up existing locks
+    int overlap_count = 0;
+    for (fl = g_locks.list; fl; fl = fl->next) {
+      if (fl->fd == fd &&  //
+          OverlapsFileLock(fl, off, len)) {
+        ++overlap_count;
+      }
+    }
+
+    // try to handle the carving cases needed by sqlite
+    if (overlap_count == 1) {
+      for (fl = g_locks.list; fl; fl = fl->next) {
+        if (fl->fd == fd &&          //
+            off <= fl->off &&        //
+            off + len >= fl->off &&  //
+            off + len < fl->off + fl->len) {
+          // cleave left side of lock
+          struct NtOverlapped ov = {.hEvent = f->handle,
+                                    .Pointer = (void *)(uintptr_t)fl->off};
+          if (!UnlockFileEx(f->handle, 0, fl->len, fl->len >> 32, &ov)) {
+            return -1;
+          }
+          fl->len = (fl->off + fl->len) - (off + len);
+          fl->off = off + len;
+          ov.Pointer = (void *)(uintptr_t)fl->off;
+          if (!LockFileEx(f->handle, kNtLockfileExclusiveLock, 0, fl->len,
+                          fl->len >> 32, &ov)) {
+            return -1;
+          }
+          return 0;
+        }
+      }
+    }
+
+    if (overlap_count) {
+      return enotsup();
+    }
+
+    return 0;
   }
 
   return einval();
 }
 
+static textwindows int sys_fcntl_nt_dupfd(int fd, int cmd, int start) {
+  if (start < 0) return einval();
+  return sys_dup_nt(fd, -1, (cmd == F_DUPFD_CLOEXEC ? O_CLOEXEC : 0), start);
+}
+
 textwindows int sys_fcntl_nt(int fd, int cmd, uintptr_t arg) {
+  int rc;
   uint32_t flags;
   if (__isfdkind(fd, kFdFile) || __isfdkind(fd, kFdSocket)) {
     if (cmd == F_GETFL) {
-      return g_fds.p[fd].flags &
-             (O_ACCMODE | O_APPEND | O_ASYNC | O_DIRECT | O_NOATIME |
-              O_NONBLOCK | O_RANDOM | O_SEQUENTIAL);
+      rc = g_fds.p[fd].flags &
+           (O_ACCMODE | O_APPEND | O_ASYNC | O_DIRECT | O_NOATIME | O_NONBLOCK |
+            O_RANDOM | O_SEQUENTIAL);
     } else if (cmd == F_SETFL) {
       // O_APPEND doesn't appear to be tunable at cursory glance
       // O_NONBLOCK might require we start doing all i/o in threads
       // O_DSYNC / O_RSYNC / O_SYNC maybe if we fsync() everything
       // O_DIRECT | O_RANDOM | O_SEQUENTIAL | O_NDELAY possible but
       // not worth it.
-      return einval();
+      rc = einval();
     } else if (cmd == F_GETFD) {
       if (g_fds.p[fd].flags & O_CLOEXEC) {
-        return FD_CLOEXEC;
+        rc = FD_CLOEXEC;
       } else {
-        return 0;
+        rc = 0;
       }
     } else if (cmd == F_SETFD) {
       if (arg & FD_CLOEXEC) {
         g_fds.p[fd].flags |= O_CLOEXEC;
-        return FD_CLOEXEC;
+        rc = FD_CLOEXEC;
       } else {
         g_fds.p[fd].flags &= ~O_CLOEXEC;
-        return 0;
+        rc = 0;
       }
     } else if (cmd == F_SETLK || cmd == F_SETLKW || cmd == F_GETLK) {
-      return sys_fcntl_nt_lock(g_fds.p + fd, cmd, arg);
+      pthread_mutex_lock(&g_locks.mu);
+      rc = sys_fcntl_nt_lock(g_fds.p + fd, fd, cmd, arg);
+      pthread_mutex_unlock(&g_locks.mu);
     } else if (cmd == F_DUPFD || cmd == F_DUPFD_CLOEXEC) {
-      return sys_fcntl_nt_dupfd(fd, cmd, arg);
+      rc = sys_fcntl_nt_dupfd(fd, cmd, arg);
     } else {
-      return einval();
+      rc = einval();
     }
   } else {
-    return ebadf();
+    rc = ebadf();
   }
+  return rc;
 }

libc/calls/fcntl.c

@@ -31,7 +31,7 @@
 #include "libc/zipos/zipos.internal.h"
 
 /**
- * Does things with file descriptor, via re-imagined hourglass api, e.g.
+ * Does things with file descriptor, e.g.
  *
  *     CHECK_NE(-1, fcntl(fd, F_SETFD, FD_CLOEXEC));
  *
@@ -41,12 +41,14 @@
  *     CHECK_GE((newfd = fcntl(oldfd, F_DUPFD,         3)), 3);
  *     CHECK_GE((newfd = fcntl(oldfd, F_DUPFD_CLOEXEC, 3)), 3);
  *
- * This function implements POSIX Advisory Locks, which let independent
- * processes (and on Windows, threads too!) read/write lock byte ranges
- * of files. See `test/libc/calls/lock_test.c` for an example.
+ * This function implements file record locking, which lets independent
+ * processes (and on Linux 3.15+, threads too!) lock arbitrary ranges
+ * associated with a file. See `test/libc/calls/lock_test.c` and other
+ * locking related tests in that folder.
  *
- * Please be warned that locks currently do nothing on Windows since
- * figuring out how to polyfill them correctly is a work in progress.
+ * On Windows, the Cosmopolitan Libc polyfill for POSIX advisory locks
+ * only implements enough of its nuances to support SQLite's needs. Some
+ * possibilities, e.g. punching holes in lock, will raise `ENOTSUP`.
  *
  * @param fd is the file descriptor
  * @param cmd can be one of:
@@ -56,12 +58,12 @@
  *     - `F_SETFL` sets file descriptor status flags
  *     - `F_DUPFD` is like dup() but `arg` is a minimum result, e.g. 3
  *     - `F_DUPFD_CLOEXEC` ditto but sets `O_CLOEXEC` on returned fd
- *     - `F_SETLK` for record locking where `arg` is `struct flock`
- *     - `F_SETLKW` ditto but waits (i.e. blocks) for lock
+ *     - `F_SETLK` for record locking where `arg` is `struct flock *`
+ *     - `F_SETLKW` ditto but waits for lock (SQLite avoids this)
  *     - `F_GETLK` to retrieve information about a record lock
- *     - `F_OFD_SETLK` for better locks on Linux and XNU
- *     - `F_OFD_SETLKW` for better locks on Linux and XNU
- *     - `F_OFD_GETLK` for better locks on Linux and XNU
+ *     - `F_OFD_SETLK` for better non-blocking lock (Linux 3.15+ only)
+ *     - `F_OFD_SETLKW` for better blocking lock (Linux 3.15+ only)
+ *     - `F_OFD_GETLK` for better lock querying (Linux 3.15+ only)
  *     - `F_FULLFSYNC` on MacOS for fsync() with release barrier
  *     - `F_BARRIERFSYNC` on MacOS for fsync() with even more barriers
  *     - `F_SETNOSIGPIPE` on MacOS and NetBSD to control `SIGPIPE`
@@ -71,7 +73,7 @@
  *     - `F_NOCACHE` on MacOS to toggle data caching
  *     - `F_GETPIPE_SZ` on Linux to get pipe size
  *     - `F_SETPIPE_SZ` on Linux to set pipe size
- *     - `F_NOTIFY` raise `SIGIO` upon `fd` events in `arg` on Linux
+ *     - `F_NOTIFY` raise `SIGIO` upon `fd` events in `arg` (Linux only)
  *       - `DN_ACCESS` for file access
  *       - `DN_MODIFY` for file modifications
  *       - `DN_CREATE` for file creations
@@ -88,6 +90,7 @@
  * @raise ENOLCK if `F_SETLKW` would have exceeded `RLIMIT_LOCKS`
  * @raise EPERM if `cmd` is `F_SETOWN` and we weren't authorized
  * @raise ESRCH if `cmd` is `F_SETOWN` and process group not found
+ * @raise ENOTSUP on Windows if locking operation isn't supported yet
  * @raise EDEADLK if `cmd` was `F_SETLKW` and waiting would deadlock
  * @raise EMFILE if `cmd` is `F_DUPFD` or `F_DUPFD_CLOEXEC` and
  *     `RLIMIT_NOFILE` would be exceeded

libc/calls/internal.h

@@ -18,7 +18,6 @@ hidden extern const struct Fd kEmptyFd;
 int __reservefd(int) hidden;
 int __reservefd_unlocked(int) hidden;
 void __releasefd(int) hidden;
-void __releasefd_unlocked(int) hidden;
 int __ensurefds(int) hidden;
 int __ensurefds_unlocked(int) hidden;
 void __printfds(void) hidden;
@@ -43,7 +42,7 @@ forceinline size_t _clampio(size_t size) {
   }
 }
 
-int sys_close_nt(struct Fd *) hidden;
+int sys_close_nt(struct Fd *, int) hidden;
 bool _check_interrupts(bool, struct Fd *) hidden;
 int sys_openat_metal(int, const char *, int, unsigned);
 

libc/calls/kill.c

@@ -17,10 +17,10 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/calls.h"
-#include "libc/intrin/strace.internal.h"
 #include "libc/calls/syscall-nt.internal.h"
 #include "libc/calls/syscall-sysv.internal.h"
 #include "libc/dce.h"
+#include "libc/intrin/strace.internal.h"
 #include "libc/str/str.h"
 
 /**
@@ -38,6 +38,10 @@
  *      >0 can be SIGINT, SIGTERM, SIGKILL, SIGUSR1, etc.
  *      =0 checks both if pid exists and we can signal it
  * @return 0 if something was accomplished, or -1 w/ errno
+ * @raise ESRCH if `pid` couldn't be found
+ * @raise EPERM if lacked permission to signal process
+ * @raise EPERM if pledge() is in play without `proc` promised
+ * @raise EINVAL if the provided `sig` is invalid or unsupported
  * @asyncsignalsafe
  */
 int kill(int pid, int sig) {

libc/calls/open-nt.c

@@ -88,7 +88,7 @@ textwindows int sys_open_nt(int dirfd, const char *file, uint32_t flags,
       rc = sys_open_nt_file(dirfd, file, flags, mode, fd);
     }
     if (rc == -1) {
-      __releasefd_unlocked(fd);
+      __releasefd(fd);
     }
     __fds_unlock();
   }

libc/calls/pipe-nt.c

@@ -41,7 +41,7 @@ textwindows int sys_pipe_nt(int pipefd[2], unsigned flags) {
     return -1;
   }
   if ((writer = __reservefd_unlocked(-1)) == -1) {
-    __releasefd_unlocked(reader);
+    __releasefd(reader);
     __fds_unlock();
     return -1;
   }
@@ -73,8 +73,8 @@ textwindows int sys_pipe_nt(int pipefd[2], unsigned flags) {
       CloseHandle(hin);
     }
   }
-  __releasefd_unlocked(writer);
-  __releasefd_unlocked(reader);
+  __releasefd(writer);
+  __releasefd(reader);
   __fds_unlock();
   return -1;
 }

libc/calls/pledge-linux.c

@@ -1606,19 +1606,26 @@ static privileged void AllowFcntlStdio(struct Filter *f) {
 
 // The second argument of fcntl() must be one of:
 //
-//   - F_GETLK (5)
-//   - F_SETLK (6)
-//   - F_SETLKW (7)
+//   - F_GETLK (0x05)
+//   - F_SETLK (0x06)
+//   - F_SETLKW (0x07)
+//   - F_OFD_GETLK (0x24)
+//   - F_OFD_SETLK (0x25)
+//   - F_OFD_SETLKW (0x26)
 //
 static privileged void AllowFcntlLock(struct Filter *f) {
   static const struct sock_filter fragment[] = {
-      /*L0*/ BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, __NR_linux_fcntl, 0, 6 - 1),
-      /*L1*/ BPF_STMT(BPF_LD | BPF_W | BPF_ABS, OFF(args[1])),
-      /*L2*/ BPF_JUMP(BPF_JMP | BPF_JGE | BPF_K, 5, 0, 5 - 3),
-      /*L3*/ BPF_JUMP(BPF_JMP | BPF_JGE | BPF_K, 8, 5 - 4, 0),
-      /*L4*/ BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
-      /*L5*/ BPF_STMT(BPF_LD | BPF_W | BPF_ABS, OFF(nr)),
-      /*L6*/ /* next filter */
+      BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, __NR_linux_fcntl, 0, 9),
+      BPF_STMT(BPF_LD | BPF_W | BPF_ABS, OFF(args[1])),
+      BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x05, 5, 0),
+      BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x06, 4, 0),
+      BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x07, 3, 0),
+      BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x24, 2, 0),
+      BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x25, 1, 0),
+      BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x26, 0, 1),
+      BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
+      BPF_STMT(BPF_LD | BPF_W | BPF_ABS, OFF(nr)),
+      /* next filter */
   };
   AppendFilter(f, PLEDGE(fragment));
 }

libc/calls/preadv.c

@@ -16,12 +16,9 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/assert.h"
 #include "libc/calls/internal.h"
 #include "libc/calls/struct/iovec.h"
 #include "libc/calls/struct/iovec.internal.h"
-#include "libc/calls/struct/sigset.h"
-#include "libc/calls/struct/sigset.internal.h"
 #include "libc/calls/syscall-sysv.internal.h"
 #include "libc/calls/syscall_support-sysv.internal.h"
 #include "libc/dce.h"
@@ -31,16 +28,13 @@
 #include "libc/intrin/likely.h"
 #include "libc/intrin/strace.internal.h"
 #include "libc/intrin/weaken.h"
-#include "libc/sysv/consts/sig.h"
 #include "libc/sysv/errfuns.h"
 #include "libc/zipos/zipos.internal.h"
 
 static ssize_t Preadv(int fd, struct iovec *iov, int iovlen, int64_t off) {
   int e, i;
   size_t got;
-  bool masked;
   ssize_t rc, toto;
-  sigset_t mask, oldmask;
 
   if (fd < 0) {
     return ebadf();
@@ -94,26 +88,17 @@ static ssize_t Preadv(int fd, struct iovec *iov, int iovlen, int64_t off) {
     if (rc == -1) {
       if (!toto) {
         toto = -1;
+      } else if (errno != EINTR) {
+        notpossible;
       }
       break;
     }
-
     got = rc;
     toto += got;
     off += got;
     if (got != iov[i].iov_len) {
       break;
     }
-
-    if (!masked) {
-      sigfillset(&mask);
-      _npassert(!sys_sigprocmask(SIG_SETMASK, &mask, &oldmask));
-      masked = true;
-    }
-  }
-
-  if (masked) {
-    _npassert(!sys_sigprocmask(SIG_SETMASK, &oldmask, 0));
   }
 
   return toto;

libc/calls/pwritev.c

@@ -16,12 +16,9 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/assert.h"
 #include "libc/calls/internal.h"
 #include "libc/calls/struct/iovec.h"
 #include "libc/calls/struct/iovec.internal.h"
-#include "libc/calls/struct/sigset.h"
-#include "libc/calls/struct/sigset.internal.h"
 #include "libc/calls/syscall-sysv.internal.h"
 #include "libc/calls/syscall_support-sysv.internal.h"
 #include "libc/dce.h"
@@ -31,17 +28,14 @@
 #include "libc/intrin/likely.h"
 #include "libc/intrin/strace.internal.h"
 #include "libc/intrin/weaken.h"
-#include "libc/sysv/consts/sig.h"
 #include "libc/sysv/errfuns.h"
 #include "libc/zipos/zipos.internal.h"
 
 static ssize_t Pwritev(int fd, const struct iovec *iov, int iovlen,
                        int64_t off) {
   int i, e;
-  bool masked;
   size_t sent;
   ssize_t rc, toto;
-  sigset_t mask, oldmask;
 
   if (fd < 0) {
     return ebadf();
@@ -95,26 +89,17 @@ static ssize_t Pwritev(int fd, const struct iovec *iov, int iovlen,
     if (rc == -1) {
       if (!toto) {
         toto = -1;
+      } else if (errno != EINTR) {
+        notpossible;
       }
       break;
     }
-
     sent = rc;
     toto += sent;
     off += sent;
     if (sent != iov[i].iov_len) {
       break;
     }
-
-    if (!masked) {
-      sigfillset(&mask);
-      _npassert(!sys_sigprocmask(SIG_SETMASK, &mask, &oldmask));
-      masked = true;
-    }
-  }
-
-  if (masked) {
-    _npassert(!sys_sigprocmask(SIG_SETMASK, &oldmask, 0));
   }
 
   return toto;

libc/calls/releasefd.c

@@ -17,11 +17,18 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/internal.h"
-#include "libc/calls/state.internal.h"
+#include "libc/intrin/atomic.h"
 #include "libc/macros.internal.h"
+#include "libc/str/str.h"
 
+// really want to avoid locking here so close() needn't block signals
 void __releasefd(int fd) {
-  __fds_lock();
-  __releasefd_unlocked(fd);
-  __fds_unlock();
+  int f1, f2;
+  if (!(0 <= fd && fd < g_fds.n)) return;
+  bzero(g_fds.p + fd, sizeof(*g_fds.p));
+  f1 = atomic_load_explicit(&g_fds.f, memory_order_relaxed);
+  do {
+    f2 = MIN(fd, f1);
+  } while (!atomic_compare_exchange_weak_explicit(
+      &g_fds.f, &f1, f2, memory_order_release, memory_order_relaxed));
 }

libc/calls/reservefd.c

@@ -22,6 +22,7 @@
 #include "libc/calls/state.internal.h"
 #include "libc/calls/struct/sigset.h"
 #include "libc/dce.h"
+#include "libc/intrin/atomic.h"
 #include "libc/intrin/cmpxchg.h"
 #include "libc/intrin/extend.internal.h"
 #include "libc/intrin/strace.internal.h"
@@ -36,6 +37,8 @@
 #include "libc/sysv/consts/sig.h"
 #include "libc/sysv/errfuns.h"
 
+// TODO(jart): make more of this code lockless
+
 static volatile size_t mapsize;
 
 /**
@@ -71,9 +74,10 @@ int __ensurefds(int fd) {
  * @asyncsignalsafe
  */
 int __reservefd_unlocked(int start) {
-  int fd;
+  int fd, f1, f2;
   for (;;) {
-    for (fd = MAX(start, g_fds.f); fd < g_fds.n; ++fd) {
+    f1 = atomic_load_explicit(&g_fds.f, memory_order_acquire);
+    for (fd = MAX(start, f1); fd < g_fds.n; ++fd) {
       if (!g_fds.p[fd].kind) {
         break;
       }
@@ -81,7 +85,11 @@ int __reservefd_unlocked(int start) {
     fd = __ensurefds_unlocked(fd);
     bzero(g_fds.p + fd, sizeof(*g_fds.p));
     if (_cmpxchg(&g_fds.p[fd].kind, kFdEmpty, kFdReserved)) {
-      _cmpxchg(&g_fds.f, fd, fd + 1);
+      // g_fds.f isn't guarded by our mutex
+      do {
+        f2 = MAX(fd + 1, f1);
+      } while (!atomic_compare_exchange_weak_explicit(
+          &g_fds.f, &f1, f2, memory_order_release, memory_order_relaxed));
       return fd;
     }
   }

libc/calls/sigaction.c

@@ -17,6 +17,7 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/assert.h"
+#include "libc/calls/blocksigs.internal.h"
 #include "libc/calls/calls.h"
 #include "libc/calls/internal.h"
 #include "libc/calls/sig.internal.h"
@@ -29,6 +30,7 @@
 #include "libc/calls/struct/sigaction.h"
 #include "libc/calls/struct/sigaction.internal.h"
 #include "libc/calls/struct/siginfo.internal.h"
+#include "libc/calls/struct/sigset.h"
 #include "libc/calls/syscall-sysv.internal.h"
 #include "libc/calls/syscall_support-sysv.internal.h"
 #include "libc/calls/ucontext.h"
@@ -474,9 +476,11 @@ int sigaction(int sig, const struct sigaction *act, struct sigaction *oldact) {
   if (sig == SIGKILL || sig == SIGSTOP) {
     rc = einval();
   } else {
+    BLOCK_SIGNALS;
     __sig_lock();
     rc = __sigaction(sig, act, oldact);
     __sig_unlock();
+    ALLOW_SIGNALS;
   }
   STRACE("sigaction(%G, %s, [%s]) → %d% m", sig, DescribeSigaction(0, act),
          DescribeSigaction(rc, oldact), rc);

libc/calls/sigblockall.c

@@ -16,13 +16,16 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/calls/internal.h"
-#include "libc/macros.internal.h"
-#include "libc/str/str.h"
+#include "libc/calls/struct/sigset.h"
 
-void __releasefd_unlocked(int fd) {
-  if (0 <= fd && fd < g_fds.n) {
-    bzero(g_fds.p + fd, sizeof(*g_fds.p));
-    g_fds.f = MIN(fd, g_fds.f);
-  }
+/**
+ * Blocks all signals without strace logging.
+ *
+ * @param neu is new signal mask for process
+ * @return old signal mask
+ */
+sigset_t _sigblockall(void) {
+  sigset_t ss;
+  sigfillset(&ss);
+  return _sigsetmask(ss);
 }

libc/calls/sigenter-openbsd.c

@@ -49,8 +49,8 @@ privileged void __sigenter_openbsd(int sig, struct siginfo_openbsd *openbsdinfo,
       __repstosb(&g.uc, 0, sizeof(g.uc));
       __siginfo2cosmo(&g.si, (void *)openbsdinfo);
       g.uc.uc_mcontext.fpregs = &g.uc.__fpustate;
-      __repmovsb(&g.uc.uc_sigmask, &ctx->sc_mask,
-                 MIN(sizeof(g.uc.uc_sigmask), sizeof(ctx->sc_mask)));
+      g.uc.uc_sigmask.__bits[0] = ctx->sc_mask;
+      g.uc.uc_sigmask.__bits[1] = 0;
       g.uc.uc_mcontext.rdi = ctx->sc_rdi;
       g.uc.uc_mcontext.rsi = ctx->sc_rsi;
       g.uc.uc_mcontext.rdx = ctx->sc_rdx;

libc/calls/sigenter-xnu.c

@@ -473,6 +473,7 @@ privileged void __sigenter_xnu(void *fn, int infostyle, int sig,
       if (xnuctx) {
         g.uc.uc_flags = xnuctx->uc_onstack ? SA_ONSTACK : 0;
         g.uc.uc_sigmask.__bits[0] = xnuctx->uc_sigmask;
+        g.uc.uc_sigmask.__bits[1] = 0;
         g.uc.uc_stack.ss_sp = xnuctx->uc_stack.ss_sp;
         g.uc.uc_stack.ss_flags = xnuctx->uc_stack.ss_flags;
         g.uc.uc_stack.ss_size = xnuctx->uc_stack.ss_size;

libc/calls/sigprocmask.c

@@ -26,7 +26,6 @@
 #include "libc/intrin/asan.internal.h"
 #include "libc/intrin/describeflags.internal.h"
 #include "libc/intrin/strace.internal.h"
-#include "libc/log/log.h"
 #include "libc/str/str.h"
 #include "libc/sysv/consts/sig.h"
 #include "libc/sysv/errfuns.h"

libc/calls/sigsetmask.c

@@ -1,7 +1,7 @@
 /*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
 │vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
 ╞══════════════════════════════════════════════════════════════════════════════╡
-│ Copyright 2021 Justine Alexandra Roberts Tunney                              │
+│ Copyright 2022 Justine Alexandra Roberts Tunney                              │
 │                                                                              │
 │ Permission to use, copy, modify, and/or distribute this software for         │
 │ any purpose with or without fee is hereby granted, provided that the         │
@@ -16,21 +16,25 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/calls/termios.h"
-#include "libc/sysv/consts/termios.h"
-#include "libc/sysv/errfuns.h"
+#include "libc/assert.h"
+#include "libc/calls/calls.h"
+#include "libc/calls/sig.internal.h"
+#include "libc/calls/struct/sigset.internal.h"
+#include "libc/dce.h"
+#include "libc/sysv/consts/sig.h"
 
-int cfsetospeed(struct termios *t, unsigned speed) {
-  if (CBAUD) {
-    if (!(speed & ~CBAUD)) {
-      t->c_cflag &= ~CBAUD;
-      t->c_cflag |= speed;
-      return 0;
-    } else {
-      return einval();
-    }
+/**
+ * Sets signal mask without strace logging.
+ *
+ * @param neu is new signal mask for process
+ * @return old signal mask
+ */
+sigset_t _sigsetmask(sigset_t neu) {
+  sigset_t res;
+  if (IsMetal() || IsWindows()) {
+    __sig_mask(SIG_SETMASK, &neu, &res);
   } else {
-    t->c_ospeed = speed;
-    return 0;
+    _npassert(!sys_sigprocmask(SIG_SETMASK, &neu, &res));
   }
+  return res;
 }

libc/calls/struct/fd.internal.h

@@ -25,7 +25,7 @@ struct Fd {
 };
 
 struct Fds {
-  int f; /* lowest free slot */
+  _Atomic(int) f; /* lowest free slot */
   size_t n;
   struct Fd *p, *e;
 };

libc/calls/struct/flock.h

@@ -9,7 +9,7 @@ struct flock {      /* cosmopolitan abi */
   int64_t l_start;  /* starting offset */
   int64_t l_len;    /* no. bytes (0 means to end of file) */
   int32_t l_pid;    /* lock owner */
-  int32_t l_sysid;  /* remote system id or zero for local */
+  int32_t l_sysid;  /* remote system id or zero for local (freebsd) */
 };
 
 COSMOPOLITAN_C_END_

libc/calls/struct/sigset.h

@@ -21,6 +21,8 @@ int sigprocmask(int, const sigset_t *, sigset_t *);
 int sigsuspend(const sigset_t *);
 int sigpending(sigset_t *);
 int pthread_sigmask(int, const sigset_t *, sigset_t *);
+sigset_t _sigsetmask(sigset_t);
+sigset_t _sigblockall(void);
 
 COSMOPOLITAN_C_END_
 #endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */

libc/calls/syscall-sysv.internal.h

@@ -10,8 +10,8 @@ COSMOPOLITAN_C_START_
 │ cosmopolitan § syscalls » system five » structless synthetic jump slots  ─╬─│┼
 ╚────────────────────────────────────────────────────────────────────────────│*/
 
+axdx_t __sys_fork(void) hidden;
 axdx_t __sys_pipe(i32[hasatleast 2], i32) hidden;
-axdx_t sys_fork(void) hidden;
 axdx_t sys_getpid(void) hidden;
 char *sys_getcwd(char *, u64) hidden;
 char *sys_getcwd_xnu(char *, u64) hidden;
@@ -46,6 +46,7 @@ i32 sys_fchownat(i32, const char *, u32, u32, u32) hidden;
 i32 sys_fcntl(i32, i32, u64) hidden;
 i32 sys_fdatasync(i32) hidden;
 i32 sys_flock(i32, i32) hidden;
+i32 sys_fork(void) hidden;
 i32 sys_fsync(i32) hidden;
 i32 sys_ftruncate(i32, i64, i64) hidden;
 i32 sys_getcontext(void *) hidden;

libc/calls/tcdrain.c

@@ -16,8 +16,41 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/calls/internal.h"
+#include "libc/calls/syscall-sysv.internal.h"
+#include "libc/calls/syscall_support-nt.internal.h"
 #include "libc/calls/termios.h"
+#include "libc/dce.h"
+#include "libc/intrin/strace.internal.h"
+#include "libc/nt/files.h"
+#include "libc/sysv/errfuns.h"
 
-int tcdrain(int fd) {
-  return ioctl(fd, TCSBRK, (void *)(intptr_t)1);
+static textwindows int sys_tcdrain_nt(int fd) {
+  if (!__isfdopen(fd)) return ebadf();
+  if (!FlushFileBuffers(g_fds.p[fd].handle)) return __winerr();
+  return 0;
+}
+
+/**
+ * Waits until all written output is transmitted.
+ *
+ * @param fd is file descriptor of tty
+ * @raise EBADF if `fd` isn't an open file descriptor
+ * @raise ENOTTY if `fd` is open but not a teletypewriter
+ * @raise EIO if process group of writer is orphoned, calling thread is
+ *     not blocking `SIGTTOU`, and process isn't ignoring `SIGTTOU`
+ * @raise ENOSYS on bare metal
+ * @asyncsignalsafe
+ */
+int tcdrain(int fd) {
+  int rc;
+  if (IsMetal()) {
+    rc = enosys();
+  } else if (!IsWindows()) {
+    rc = sys_ioctl(fd, TCSBRK, (void *)(intptr_t)1);
+  } else {
+    rc = sys_tcdrain_nt(fd);
+  }
+  STRACE("tcdrain(%d) → %d% m", fd, rc);
+  return rc;
 }

libc/calls/tcflow.c

@@ -16,31 +16,91 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/calls/internal.h"
 #include "libc/calls/struct/termios.h"
 #include "libc/calls/syscall-sysv.internal.h"
+#include "libc/calls/syscall_support-nt.internal.h"
 #include "libc/calls/termios.h"
 #include "libc/dce.h"
+#include "libc/fmt/itoa.h"
+#include "libc/intrin/strace.internal.h"
+#include "libc/mem/alloca.h"
+#include "libc/nt/comms.h"
 #include "libc/sysv/consts/termios.h"
 #include "libc/sysv/errfuns.h"
 
+#define kNtPurgeTxabort 1
+#define kNtPurgeRxabort 2
+
+static const char *DescribeFlow(char buf[12], int action) {
+  if (action == TCOOFF) return "TCOOFF";
+  if (action == TCOON) return "TCOON";
+  if (action == TCIOFF) return "TCIOFF";
+  if (action == TCION) return "TCION";
+  FormatInt32(buf, action);
+  return buf;
+}
+
+static int sys_tcflow_bsd(int fd, int action) {
+  int rc;
+  uint8_t c;
+  struct termios t;
+  if (action == TCOOFF) return sys_ioctl(fd, TIOCSTOP, 0);
+  if (action == TCOON) return sys_ioctl(fd, TIOCSTART, 0);
+  if (action != TCIOFF && action != TCION) return einval();
+  if (sys_ioctl(fd, TCGETS, &t) == -1) return -1;
+  c = t.c_cc[action == TCIOFF ? VSTOP : VSTART];
+  if (c == 255) return 0;  // code is disabled
+  if (sys_write(fd, &c, 1) == -1) return -1;
+  return 0;
+}
+
+static dontinline textwindows int sys_tcflow_nt(int fd, int action) {
+  bool32 ok;
+  int64_t h;
+  if (!__isfdopen(fd)) return ebadf();
+  h = g_fds.p[fd].handle;
+  if (action == TCOOFF) {
+    ok = PurgeComm(h, kNtPurgeTxabort);
+  } else if (action == TCIOFF) {
+    ok = PurgeComm(h, kNtPurgeRxabort);
+  } else if (action == TCOON || action == TCION) {
+    ok = ClearCommBreak(h);
+  } else {
+    return einval();
+  }
+  return ok ? 0 : __winerr();
+}
+
 /**
  * Changes flow of teletypewriter data.
  *
- * - `TCOOFF` suspends output
- * - `TCOON` resumes output
- * - `TCIOFF` transmits a STOP character
- * - `TCION` transmits a START character
+ * @param fd is file descriptor of tty
+ * @param action may be one of:
+ *     - `TCOOFF` to suspend output
+ *     - `TCOON` to resume output
+ *     - `TCIOFF` to transmit a `STOP` character
+ *     - `TCION` to transmit a `START` character
+ * @return 0 on success, or -1 w/ errno
+ * @raise EINVAL if `action` is invalid
+ * @raise ENOSYS on Windows and Bare Metal
+ * @raise EBADF if `fd` isn't an open file descriptor
+ * @raise ENOTTY if `fd` is open but not a teletypewriter
+ * @raise EIO if process group of writer is orphoned, calling thread is
+ *     not blocking `SIGTTOU`, and process isn't ignoring `SIGTTOU`
+ * @asyncsignalsafe
  */
 int tcflow(int fd, int action) {
-  uint8_t c;
-  struct termios t;
-  if (!IsBsd()) return sys_ioctl(fd, TCXONC, action);
-  if (action == TCOOFF) return sys_ioctl(fd, TIOCSTOP, 0);
-  if (action == TCOON) return sys_ioctl(fd, TIOCSTART, 0);
-  if (action != TCIOFF && action != TCION) return einval();
-  if (tcgetattr(fd, &t) == -1) return -1;
-  if ((c = t.c_cc[action == TCIOFF ? VSTOP : VSTART]) != 255) {
-    if (sys_write(fd, &c, 1) == -1) return -1;
+  int rc;
+  if (IsMetal()) {
+    rc = enosys();
+  } else if (IsBsd()) {
+    rc = sys_ioctl(fd, TCXONC, action);
+  } else if (!IsWindows()) {
+    rc = sys_ioctl(fd, TCXONC, action);
+  } else {
+    rc = sys_tcflow_nt(fd, action);
   }
-  return 0;
+  STRACE("tcflow(%d, %s) → %d% m", fd, DescribeFlow(alloca(12), action), rc);
+  return rc;
 }

libc/calls/tcflush.c

@@ -16,17 +16,70 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/calls/internal.h"
+#include "libc/calls/syscall-nt.internal.h"
 #include "libc/calls/syscall-sysv.internal.h"
+#include "libc/calls/syscall_support-nt.internal.h"
 #include "libc/calls/termios.h"
+#include "libc/dce.h"
+#include "libc/fmt/itoa.h"
+#include "libc/intrin/strace.internal.h"
+#include "libc/mem/alloca.h"
+#include "libc/nt/comms.h"
+#include "libc/sysv/consts/termios.h"
+#include "libc/sysv/errfuns.h"
+
+#define kNtPurgeTxclear 4
+#define kNtPurgeRxclear 8
+
+static const char *DescribeFlush(char buf[12], int action) {
+  if (action == TCIFLUSH) return "TCIFLUSH";
+  if (action == TCOFLUSH) return "TCOFLUSH";
+  if (action == TCIOFLUSH) return "TCIOFLUSH";
+  FormatInt32(buf, action);
+  return buf;
+}
+
+static dontinline textwindows int sys_tcflush_nt(int fd, int queue) {
+  bool32 ok;
+  int64_t h;
+  if (!__isfdopen(fd)) return ebadf();
+  ok = true;
+  h = g_fds.p[fd].handle;
+  if (queue == TCIFLUSH || queue == TCIOFLUSH) {
+    ok &= !!PurgeComm(h, kNtPurgeRxclear);
+  }
+  if (queue == TCOFLUSH || queue == TCIOFLUSH) {
+    ok &= !!PurgeComm(h, kNtPurgeTxclear);
+  }
+  return ok ? 0 : __winerr();
+}
 
 /**
- * Flushes teletypewriter data.
+ * Discards queued data on teletypewriter.
  *
- * - `TCIFLUSH` flushes data received but not read
- * - `TCOFLUSH` flushes data written but not transmitted
- * - `TCIOFLUSH` does both `TCOFLUSH` and `TCIFLUSH`
+ * @param queue may be one of:
+ *     - `TCIFLUSH` flushes data received but not read
+ *     - `TCOFLUSH` flushes data written but not transmitted
+ *     - `TCIOFLUSH` does both `TCOFLUSH` and `TCIFLUSH`
+ * @return 0 on success, or -1 w/ errno
+ * @raise EINVAL if `action` is invalid
+ * @raise EBADF if `fd` isn't an open file descriptor
+ * @raise ENOTTY if `fd` is open but not a teletypewriter
+ * @raise EIO if process group of writer is orphoned, calling thread is
+ *     not blocking `SIGTTOU`, and process isn't ignoring `SIGTTOU`
+ * @raise ENOSYS on bare metal
+ * @asyncsignalsafe
  */
 int tcflush(int fd, int queue) {
-  /* TODO(jart): Windows? */
-  return sys_ioctl(fd, TCFLSH, queue);
+  int rc;
+  if (IsMetal()) {
+    rc = enosys();
+  } else if (!IsWindows()) {
+    rc = sys_ioctl(fd, TCFLSH, queue);
+  } else {
+    rc = sys_tcflush_nt(fd, queue);
+  }
+  STRACE("tcflush(%d, %s) → %d% m", fd, DescribeFlush(alloca(12), queue), rc);
+  return rc;
 }

libc/calls/tcgetpgrp.c

@@ -16,16 +16,29 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/calls/calls.h"
+#include "libc/calls/syscall-sysv.internal.h"
 #include "libc/calls/termios.h"
+#include "libc/dce.h"
+#include "libc/intrin/strace.internal.h"
 #include "libc/sysv/consts/termios.h"
+#include "libc/sysv/errfuns.h"
 
 /**
  * Returns which process group controls terminal.
+ *
+ * @return process group id on success, or -1 w/ errno
+ * @raise ENOTTY if `fd` is isn't controlling teletypewriter
+ * @raise EBADF if `fd` isn't an open file descriptor
+ * @raise ENOSYS on Windows and Bare Metal
  * @asyncsignalsafe
  */
-int32_t tcgetpgrp(int fd) {
-  int pgrp;
-  if (ioctl(fd, TIOCGPGRP, &pgrp) < 0) return -1;
-  return pgrp;
+int tcgetpgrp(int fd) {
+  int rc, pgrp;
+  if (IsWindows() || IsMetal()) {
+    rc = enosys();
+  } else {
+    rc = sys_ioctl(fd, TIOCGPGRP, &pgrp);
+  }
+  STRACE("tcgetpgrp(%d) → %d% m", fd, rc == -1 ? rc : pgrp);
+  return rc == -1 ? rc : pgrp;
 }

libc/calls/tcsendbreak.c

@@ -17,18 +17,53 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/calls.h"
+#include "libc/calls/internal.h"
 #include "libc/calls/syscall-sysv.internal.h"
+#include "libc/calls/syscall_support-nt.internal.h"
 #include "libc/calls/termios.h"
 #include "libc/dce.h"
+#include "libc/intrin/strace.internal.h"
+#include "libc/nt/comms.h"
 #include "libc/sysv/consts/termios.h"
+#include "libc/sysv/errfuns.h"
 
-int tcsendbreak(int fd, int len) {
-  if (!IsBsd()) {
-    return sys_ioctl(fd, TCSBRK, 0);
-  } else {
-    if (sys_ioctl(fd, TIOCSBRK, 0) == -1) return -1;
-    usleep(400000);
-    if (sys_ioctl(fd, TIOCCBRK, 0) == -1) return -1;
-    return 0;
-  }
+static int sys_tcsendbreak_bsd(int fd) {
+  if (sys_ioctl(fd, TIOCSBRK, 0) == -1) return -1;
+  usleep(400000);
+  if (sys_ioctl(fd, TIOCCBRK, 0) == -1) return -1;
+  return 0;
+}
+
+static textwindows int sys_tcsendbreak_nt(int fd) {
+  if (!__isfdopen(fd)) return ebadf();
+  if (!TransmitCommChar(g_fds.p[fd].handle, '\0')) return __winerr();
+  return 0;
+}
+
+/**
+ * Sends break.
+ *
+ * @param fd is file descriptor of tty
+ * @param duration of 0 sends a break for 0.25-0.5 seconds, and other
+ *     durations are treated the same by this implementation
+ * @raise EBADF if `fd` isn't an open file descriptor
+ * @raise ENOTTY if `fd` is open but not a teletypewriter
+ * @raise EIO if process group of writer is orphoned, calling thread is
+ *     not blocking `SIGTTOU`, and process isn't ignoring `SIGTTOU`
+ * @raise ENOSYS on bare metal
+ * @asyncsignalsafe
+ */
+int tcsendbreak(int fd, int duration) {
+  int rc;
+  if (IsMetal()) {
+    rc = enosys();
+  } else if (IsBsd()) {
+    rc = sys_tcsendbreak_bsd(fd);
+  } else if (!IsWindows()) {
+    rc = sys_ioctl(fd, TCSBRK, 0);
+  } else {
+    rc = sys_tcsendbreak_nt(fd);
+  }
+  STRACE("tcsendbreak(%d, %u) → %d% m", fd, duration, rc);
+  return rc;
 }

libc/calls/tcsetpgrp.c

@@ -17,14 +17,33 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/calls.h"
+#include "libc/calls/syscall-sysv.internal.h"
 #include "libc/calls/termios.h"
+#include "libc/dce.h"
+#include "libc/intrin/strace.internal.h"
 #include "libc/sysv/consts/termios.h"
+#include "libc/sysv/errfuns.h"
 
 /**
- * Puts process group in control of terminal.
+ * Sets foreground process group id.
+ *
+ * @return 0 on success, or -1 w/ errno
+ * @raise EINVAL if `pgrp` is invalid
+ * @raise ENOSYS on Windows and Bare Metal
+ * @raise EBADF if `fd` isn't an open file descriptor
+ * @raise EPERM if `pgrp` didn't match process in our group
+ * @raise ENOTTY if `fd` is isn't controlling teletypewriter
+ * @raise EIO if process group of writer is orphoned, calling thread is
+ *     not blocking `SIGTTOU`, and process isn't ignoring `SIGTTOU`
  * @asyncsignalsafe
  */
-int tcsetpgrp(int fd, int32_t pgrp) {
-  int pgrp_int = pgrp;
-  return ioctl(fd, TIOCSPGRP, &pgrp_int);
+int tcsetpgrp(int fd, int pgrp) {
+  int rc;
+  if (IsWindows() || IsMetal()) {
+    rc = enosys();
+  } else {
+    rc = sys_ioctl(fd, TIOCSPGRP, &pgrp);
+  }
+  STRACE("tcsetpgrp(%d, %d) → %d% m", fd, pgrp, rc);
+  return rc;
 }

libc/intrin/_getenv.c

@@ -1,7 +1,7 @@
 /*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
 │vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
 ╞══════════════════════════════════════════════════════════════════════════════╡
-│ Copyright 2021 Justine Alexandra Roberts Tunney                              │
+│ Copyright 2022 Justine Alexandra Roberts Tunney                              │
 │                                                                              │
 │ Permission to use, copy, modify, and/or distribute this software for         │
 │ any purpose with or without fee is hereby granted, provided that the         │
@@ -16,18 +16,26 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/calls/termios.h"
-#include "libc/sysv/errfuns.h"
+#include "libc/dce.h"
+#include "libc/intrin/_getenv.internal.h"
 
-int cfsetispeed(struct termios *t, unsigned speed) {
-  if (speed) {
-    if (CBAUD) {
-      if (speed & ~CBAUD) return einval();
-      t->c_cflag &= ~CBAUD;
-      t->c_cflag |= speed;
-    } else {
-      t->c_ispeed = speed;
+#define ToUpper(c) \
+  (IsWindows() && (c) >= 'a' && (c) <= 'z' ? (c) - 'a' + 'A' : (c))
+
+struct Env _getenv(char **p, const char *k) {
+  char *t;
+  int i, j;
+  for (i = 0; (t = p[i]); ++i) {
+    for (j = 0;; ++j) {
+      if (!k[j] || k[j] == '=') {
+        if (!t[j]) return (struct Env){t + j, i};
+        if (t[j] == '=') return (struct Env){t + j + 1, i};
+        break;
+      }
+      if (ToUpper(k[j] & 255) != ToUpper(t[j] & 255)) {
+        break;
+      }
     }
   }
-  return 0;
+  return (struct Env){0, i};
 }

libc/intrin/_getenv.internal.h

@@ -0,0 +1,15 @@
+#ifndef COSMOPOLITAN_LIBC_INTRIN__GETENV_INTERNAL_H_
+#define COSMOPOLITAN_LIBC_INTRIN__GETENV_INTERNAL_H_
+#if !(__ASSEMBLER__ + __LINKER__ + 0)
+COSMOPOLITAN_C_START_
+
+struct Env {
+  char *s;
+  int i;
+};
+
+struct Env _getenv(char **, const char *) hidden;
+
+COSMOPOLITAN_C_END_
+#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
+#endif /* COSMOPOLITAN_LIBC_INTRIN__GETENV_INTERNAL_H_ */

libc/intrin/bt.c

@@ -17,10 +17,12 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/errno.h"
-#include "libc/intrin/intrin.h"
 #include "libc/intrin/kprintf.h"
 #include "libc/intrin/weaken.h"
 #include "libc/log/backtrace.internal.h"
+#include "libc/runtime/symbols.internal.h"
+
+static _Thread_local bool noreentry;
 
 /**
  * Shows backtrace if crash reporting facilities are linked.
@@ -28,12 +30,20 @@
 void _bt(const char *fmt, ...) {
   int e;
   va_list va;
+
+  if (!noreentry) {
+    noreentry = true;
+  } else {
+    return;
+  }
+
   if (fmt) {
     va_start(va, fmt);
     kvprintf(fmt, va);
     va_end(va);
   }
-  if (_weaken(ShowBacktrace)) {
+
+  if (_weaken(ShowBacktrace) && _weaken(GetSymbolTable)) {
     e = errno;
     _weaken(ShowBacktrace)(2, __builtin_frame_address(0));
     errno = e;
@@ -41,5 +51,18 @@ void _bt(const char *fmt, ...) {
     kprintf("_bt() can't show backtrace because you need:\n"
             "\tSTATIC_YOINK(\"ShowBacktrace\");\n"
             "to be linked.\n");
+    if (_weaken(PrintBacktraceUsingSymbols) && _weaken(GetSymbolTable)) {
+      e = errno;
+      _weaken(PrintBacktraceUsingSymbols)(2, __builtin_frame_address(0),
+                                          _weaken(GetSymbolTable)());
+      errno = e;
+    } else {
+      kprintf("_bt() can't show backtrace because you need:\n"
+              "\tSTATIC_YOINK(\"PrintBacktraceUsingSymbols\");\n"
+              "\tSTATIC_YOINK(\"GetSymbolTable\");\n"
+              "to be linked.\n");
+    }
   }
+
+  noreentry = false;
 }

libc/intrin/clearenv.c

@@ -21,9 +21,11 @@
 
 /**
  * Removes all environment variables.
+ *
+ * @return 0 on success, or nonzero on error
  */
 int clearenv(void) {
+  environ = 0;
   STRACE("clearenv() → 0");
-  environ = NULL;
   return 0;
 }

libc/intrin/describeflock.c

@@ -56,7 +56,7 @@ const char *(DescribeFlock)(char buf[N], int cmd, const struct flock *l) {
     append(", .l_pid=%d", l->l_pid);
   }
 
-  if (l->l_sysid) {
+  if (IsFreebsd() && l->l_sysid) {
     append(", .l_sysid=%d", l->l_sysid);
   }
 

libc/intrin/describesigaction.c

@@ -16,23 +16,68 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/calls/calls.h"
 #include "libc/calls/struct/sigaction.h"
+#include "libc/calls/struct/sigset.h"
 #include "libc/calls/struct/sigset.internal.h"
 #include "libc/dce.h"
 #include "libc/intrin/asan.internal.h"
 #include "libc/intrin/describeflags.internal.h"
 #include "libc/intrin/kprintf.h"
+#include "libc/mem/alloca.h"
+#include "libc/sysv/consts/sa.h"
 
-const char *(DescribeSigaction)(char buf[256], int rc,
+static const char *DescribeSigHandler(char buf[64], void f(int)) {
+  if (f == SIG_ERR) return "SIG_ERR";
+  if (f == SIG_DFL) return "SIG_DFL";
+  if (f == SIG_IGN) return "SIG_IGN";
+  ksnprintf(buf, 64, "%t", f);
+  return buf;
+}
+
+static const char *DescribeSigFlags(char buf[64], int x) {
+  const struct DescribeFlags kSigFlags[] = {
+      {SA_NOCLDSTOP, "NOCLDSTOP"},  //
+      {SA_NOCLDWAIT, "NOCLDWAIT"},  //
+      {SA_SIGINFO, "SIGINFO"},      //
+      {SA_ONSTACK, "ONSTACK"},      //
+      {SA_RESTART, "RESTART"},      //
+      {SA_NODEFER, "NODEFER"},      //
+      {SA_RESETHAND, "RESETHAND"},  //
+      {SA_NOMASK, "NOMASK"},        //
+      {SA_ONESHOT, "ONESHOT"},      //
+  };
+  return DescribeFlags(buf, 64, kSigFlags, ARRAYLEN(kSigFlags), "SA_", x);
+}
+
+#define N 256
+
+#define append(...) o += ksnprintf(buf + o, N - o, __VA_ARGS__)
+
+const char *(DescribeSigaction)(char buf[N], int rc,
                                 const struct sigaction *sa) {
+  int o = 0;
+  char b64[64];
+
   if (rc == -1) return "n/a";
   if (!sa) return "NULL";
   if ((!IsAsan() && kisdangerous(sa)) ||
       (IsAsan() && !__asan_is_valid(sa, sizeof(*sa)))) {
-    ksnprintf(buf, 256, "%p", sa);
-  } else {
-    ksnprintf(buf, 256, "{.sa_handler=%t, .sa_flags=%#lx, .sa_mask=%s}",
-              sa->sa_handler, sa->sa_flags, DescribeSigset(rc, &sa->sa_mask));
+    ksnprintf(buf, N, "%p", sa);
+    return buf;
   }
+
+  append("{.sa_handler=%s", DescribeSigHandler(b64, sa->sa_handler));
+
+  if (sa->sa_flags) {
+    append(", .sa_flags=%s", DescribeSigFlags(b64, sa->sa_flags));
+  }
+
+  if (!sigisemptyset(&sa->sa_mask)) {
+    append(", .sa_mask=%s", DescribeSigset(rc, &sa->sa_mask));
+  }
+
+  append("}");
+
   return buf;
 }

libc/intrin/describesigset.c

@@ -23,6 +23,7 @@
 #include "libc/intrin/kprintf.h"
 #include "libc/intrin/popcnt.h"
 #include "libc/str/str.h"
+#include "libc/sysv/consts/limits.h"
 #include "libc/sysv/consts/sig.h"
 
 #define N 128
@@ -31,6 +32,7 @@
 
 const char *(DescribeSigset)(char buf[N], int rc, const sigset_t *ss) {
   bool gotsome;
+  const char *s;
   int sig, o = 0;
   sigset_t sigset;
 
@@ -45,9 +47,9 @@ const char *(DescribeSigset)(char buf[N], int rc, const sigset_t *ss) {
   if (sigcountset(ss) > 16) {
     append("~");
     sigemptyset(&sigset);
-    for (sig = 1; sig <= NSIG; ++sig) {
+    for (sig = 1; sig <= _NSIG; ++sig) {
       if (!sigismember(ss, sig)) {
-        sigaddset(&sigset, sig);
+        sigset.__bits[(sig - 1) >> 6] |= 1ull << ((sig - 1) & 63);
       }
     }
   } else {
@@ -56,14 +58,18 @@ const char *(DescribeSigset)(char buf[N], int rc, const sigset_t *ss) {
 
   append("{");
   gotsome = false;
-  for (sig = 1; sig <= NSIG; ++sig) {
+  for (sig = 1; sig <= _NSIG; ++sig) {
     if (sigismember(&sigset, sig) > 0) {
       if (gotsome) {
         append(",");
       } else {
         gotsome = true;
       }
-      append("%s", strsignal(sig) + 3);
+      s = strsignal(sig);
+      if (s[0] == 'S' && s[1] == 'I' && s[2] == 'G') {
+        s += 3;
+      }
+      append("%s", s);
     }
   }
   append("}");

libc/intrin/extend.c

@@ -19,6 +19,7 @@
 #include "libc/assert.h"
 #include "libc/calls/calls.h"
 #include "libc/dce.h"
+#include "libc/errno.h"
 #include "libc/intrin/asan.internal.h"
 #include "libc/intrin/asancodes.h"
 #include "libc/macros.internal.h"
@@ -29,17 +30,26 @@
 
 #define G FRAMESIZE
 
-static void _mapframe(void *p, int f) {
-  int prot, flags;
+static void *_mapframe(void *p, int f) {
+  int rc, prot, flags;
   struct DirectMap dm;
   prot = PROT_READ | PROT_WRITE;
   flags = f | MAP_ANONYMOUS | MAP_FIXED;
-  _npassert((dm = sys_mmap(p, G, prot, flags, -1, 0)).addr == p);
-  __mmi_lock();
-  _npassert(!TrackMemoryInterval(&_mmi, (uintptr_t)p >> 16, (uintptr_t)p >> 16,
-                                 dm.maphandle, prot, flags, false, false, 0,
-                                 G));
-  __mmi_unlock();
+  if ((dm = sys_mmap(p, G, prot, flags, -1, 0)).addr == p) {
+    __mmi_lock();
+    rc = TrackMemoryInterval(&_mmi, (uintptr_t)p >> 16, (uintptr_t)p >> 16,
+                             dm.maphandle, prot, flags, false, false, 0, G);
+    __mmi_unlock();
+    if (!rc) {
+      return p;
+    } else {
+      _unassert(errno == ENOMEM);
+      return 0;
+    }
+  } else {
+    _unassert(errno == ENOMEM);
+    return 0;
+  }
 }
 
 /**
@@ -58,7 +68,8 @@ static void _mapframe(void *p, int f) {
  * @param e points to end of memory that's allocated
  * @param h is highest address to which `e` may grow
  * @param f should be `MAP_PRIVATE` or `MAP_SHARED`
- * @return new value for `e`
+ * @return new value for `e` or null w/ errno
+ * @raise ENOMEM if we require more vespene gas
  */
 noasan void *_extend(void *p, size_t n, void *e, int f, intptr_t h) {
   char *q;
@@ -67,10 +78,10 @@ noasan void *_extend(void *p, size_t n, void *e, int f, intptr_t h) {
   for (q = e; q < ((char *)p + n); q += 8) {
     if (!((uintptr_t)q & (G - 1))) {
       _unassert(q + G <= (char *)h);
-      _mapframe(q, f);
+      if (!_mapframe(q, f)) return 0;
       if (IsAsan()) {
         if (!((uintptr_t)SHADOW(q) & (G - 1))) {
-          _mapframe(SHADOW(q), f);
+          if (!_mapframe(SHADOW(q), f)) return 0;
           __asan_poison(q, G << kAsanScale, kAsanProtected);
         }
       }

libc/intrin/getenv.c

@@ -1,7 +1,7 @@
 /*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
 │vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
 ╞══════════════════════════════════════════════════════════════════════════════╡
-│ Copyright 2022 Gavin Arthur Hayes                                            │
+│ Copyright 2020 Justine Alexandra Roberts Tunney                              │
 │                                                                              │
 │ Permission to use, copy, modify, and/or distribute this software for         │
 │ any purpose with or without fee is hereby granted, provided that the         │
@@ -16,18 +16,28 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/mem/mem.h"
+#include "libc/intrin/_getenv.internal.h"
+#include "libc/intrin/strace.internal.h"
 #include "libc/runtime/runtime.h"
-#include "libc/testlib/testlib.h"
 
-TEST(putenv, test) {
-  EXPECT_EQ(0, clearenv());
-  EXPECT_EQ(0, putenv("hi=there"));
-  EXPECT_STREQ("there", getenv("hi"));
-  EXPECT_EQ(0, clearenv());
-  EXPECT_EQ(0, putenv("hi=theretwo"));
-  EXPECT_STREQ("theretwo", getenv("hi"));
-  EXPECT_EQ(0, clearenv());
-  EXPECT_EQ(0, setenv("hi", "therethree", 0));
-  EXPECT_STREQ("therethree", getenv("hi"));
+/**
+ * Returns value of environment variable, or NULL if not found.
+ *
+ * Environment variables can store empty string on Unix but not Windows.
+ *
+ * @return pointer to value of `environ` entry, or null if not found
+ */
+char *getenv(const char *s) {
+  char **p;
+  struct Env e;
+  if (!s) return 0;
+  if (!(p = environ)) return 0;
+  e = _getenv(p, s);
+#if SYSDEBUG
+  if (!(s[0] == 'T' && s[1] == 'Z' && !s[2])) {
+    // TODO(jart): memoize TZ or something
+    STRACE("getenv(%#s) → %#s", s, e.s);
+  }
+#endif
+  return e.s;
 }

libc/intrin/intrin.mk

@@ -7,6 +7,7 @@ LIBC_INTRIN_ARTIFACTS += LIBC_INTRIN_A
 LIBC_INTRIN = $(LIBC_INTRIN_A_DEPS) $(LIBC_INTRIN_A)
 LIBC_INTRIN_A = o/$(MODE)/libc/intrin/intrin.a
 LIBC_INTRIN_A_HDRS = $(filter %.h,$(LIBC_INTRIN_A_FILES))
+LIBC_INTRIN_A_INCS = $(filter %.inc,$(LIBC_INTRIN_A_FILES))
 LIBC_INTRIN_A_SRCS_S = $(filter %.S,$(LIBC_INTRIN_A_FILES))
 LIBC_INTRIN_A_SRCS_C = $(filter %.c,$(LIBC_INTRIN_A_FILES))
 LIBC_INTRIN_A_SRCS = $(LIBC_INTRIN_A_SRCS_S) $(LIBC_INTRIN_A_SRCS_C)
@@ -121,7 +122,6 @@ o/$(MODE)/libc/intrin/describeprotflags.o: private	\
 			-fno-sanitize=address
 
 o/$(MODE)/libc/intrin/exit1.greg.o			\
-o/$(MODE)/libc/intrin/getenv.greg.o			\
 o/$(MODE)/libc/intrin/wsarecv.o				\
 o/$(MODE)/libc/intrin/wsarecvfrom.o			\
 o/$(MODE)/libc/intrin/createfile.o			\
@@ -182,6 +182,7 @@ o/$(MODE)/libc/intrin/memmove.o: private		\
 
 LIBC_INTRIN_LIBS = $(foreach x,$(LIBC_INTRIN_ARTIFACTS),$($(x)))
 LIBC_INTRIN_HDRS = $(foreach x,$(LIBC_INTRIN_ARTIFACTS),$($(x)_HDRS))
+LIBC_INTRIN_INCS = $(foreach x,$(LIBC_INTRIN_ARTIFACTS),$($(x)_INCS))
 LIBC_INTRIN_SRCS = $(foreach x,$(LIBC_INTRIN_ARTIFACTS),$($(x)_SRCS))
 LIBC_INTRIN_CHECKS = $(foreach x,$(LIBC_INTRIN_ARTIFACTS),$($(x)_CHECKS))
 LIBC_INTRIN_OBJS = $(foreach x,$(LIBC_INTRIN_ARTIFACTS),$($(x)_OBJS))

libc/intrin/kmalloc.c

@@ -29,7 +29,7 @@
 #include "libc/thread/thread.h"
 #include "libc/thread/tls.h"
 
-#define KMALLOC_ALIGN __BIGGEST_ALIGNMENT__
+#define KMALLOC_ALIGN sizeof(intptr_t)
 
 static struct {
   char *endptr;
@@ -55,21 +55,37 @@ __attribute__((__constructor__)) static void kmalloc_init(void) {
  * The code malloc() depends upon uses this function to allocate memory.
  * The returned memory can't be freed, and leak detection is impossible.
  * This function panics when memory isn't available.
+ *
+ * Memory returned by this function is aligned on the word size, and as
+ * such, kmalloc() shouldn't be used for vector operations.
+ *
+ * @return zero-initialized memory on success, or null w/ errno
+ * @raise ENOMEM if we require more vespene gas
  */
 void *kmalloc(size_t size) {
-  char *start;
-  size_t i, n;
+  char *p, *e;
+  size_t i, n, t;
   n = ROUNDUP(size + (IsAsan() * 8), KMALLOC_ALIGN);
   kmalloc_lock();
-  i = g_kmalloc.total;
-  g_kmalloc.total += n;
-  start = (char *)kMemtrackKmallocStart;
-  if (!g_kmalloc.endptr) g_kmalloc.endptr = start;
-  g_kmalloc.endptr =
-      _extend(start, g_kmalloc.total, g_kmalloc.endptr, MAP_PRIVATE,
-              kMemtrackKmallocStart + kMemtrackKmallocSize);
+  t = g_kmalloc.total;
+  e = g_kmalloc.endptr;
+  i = t;
+  t += n;
+  p = (char *)kMemtrackKmallocStart;
+  if (!e) e = p;
+  if ((e = _extend(p, t, e, MAP_PRIVATE,
+                   kMemtrackKmallocStart + kMemtrackKmallocSize))) {
+    g_kmalloc.endptr = e;
+    g_kmalloc.total = t;
+  } else {
+    p = 0;
+  }
   kmalloc_unlock();
-  _unassert(!((intptr_t)(start + i) & (KMALLOC_ALIGN - 1)));
-  if (IsAsan()) __asan_poison(start + i + size, n - size, kAsanHeapOverrun);
-  return start + i;
+  if (p) {
+    _unassert(!((intptr_t)(p + i) & (KMALLOC_ALIGN - 1)));
+    if (IsAsan()) __asan_poison(p + i + size, n - size, kAsanHeapOverrun);
+    return p + i;
+  } else {
+    return 0;
+  }
 }

libc/intrin/kmalloc.h

@@ -3,7 +3,7 @@
 #if !(__ASSEMBLER__ + __LINKER__ + 0)
 COSMOPOLITAN_C_START_
 
-void *kmalloc(size_t) attributeallocsize((1)) mallocesque returnsnonnull;
+void *kmalloc(size_t) mallocesque attributeallocsize((1)) returnsaligned((8));
 
 COSMOPOLITAN_C_END_
 #endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */

libc/intrin/putenv.c

@@ -16,19 +16,16 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/intrin/_getenv.internal.h"
+#include "libc/intrin/kmalloc.h"
 #include "libc/intrin/strace.internal.h"
-#include "libc/dce.h"
 #include "libc/macros.internal.h"
-#include "libc/mem/alg.h"
 #include "libc/mem/internal.h"
-#include "libc/mem/mem.h"
 #include "libc/runtime/runtime.h"
-#include "libc/str/str.h"
-#include "libc/sysv/errfuns.h"
 
 #define ToUpper(c) ((c) >= 'a' && (c) <= 'z' ? (c) - 'a' + 'A' : (c))
 
-static bool once;
+static char **expected;
 static size_t capacity;
 
 static size_t GetEnvironLen(char **env) {
@@ -37,98 +34,69 @@ static size_t GetEnvironLen(char **env) {
   return p - env;
 }
 
-static void RestoreOriginalEnvironment(char **envp) {
-  environ = envp;
-}
-
-static void PutEnvImplAtExit(void *p) {
-  free(p);
-}
-
-static void FreeEnviron(char **env) {
-  char **a;
-  for (a = env; *a; ++a) {
-    free(*a);
-  }
-  free(env);
-}
-
-static void GrowEnviron(void) {
+static char **GrowEnviron(char **a) {
   size_t n, c;
-  char **a, **b, **p;
-  a = environ;
+  char **b, **p;
+  if (!a) a = environ;
   n = a ? GetEnvironLen(a) : 0;
   c = MAX(16ul, n) << 1;
-  b = calloc(c, sizeof(char *));
-  if (a) {
-    for (p = b; *a;) {
-      *p++ = strdup(*a++);
+  if ((b = kmalloc(c * sizeof(char *)))) {
+    if (a) {
+      for (p = b; *a;) {
+        *p++ = *a++;
+      }
     }
+    environ = b;
+    expected = b;
+    capacity = c;
+    return b;
+  } else {
+    return 0;
   }
-  __cxa_atexit(FreeEnviron, b, 0);
-  environ = b;
-  capacity = c;
 }
 
 int PutEnvImpl(char *s, bool overwrite) {
-  char *p;
-  unsigned i, namelen;
-  if (!once) {
-    __cxa_atexit(RestoreOriginalEnvironment, environ, 0);
-    GrowEnviron();
-    once = true;
-  } else if (!environ) {
-    GrowEnviron();
-  }
-  for (p = s; *p && *p != '='; ++p) {
-    if (IsWindows()) {
-      *p = ToUpper(*p);
+  char **p;
+  struct Env e;
+  if (!(p = environ)) {
+    if (!(p = GrowEnviron(0))) {
+      return -1;
     }
   }
-  if (*p != '=') goto Fail;
-  namelen = p + 1 - s;
-  for (i = 0; environ[i]; ++i) {
-    if (!strncmp(environ[i], s, namelen)) {
-      if (!overwrite) {
-        free(s);
-        return 0;
-      }
-      goto Replace;
+  e = _getenv(p, s);
+  if (e.s && !overwrite) {
+    return 0;
+  }
+  if (e.s) {
+    p[e.i] = s;
+    return 0;
+  }
+  if (p != expected) {
+    capacity = e.i;
+  }
+  if (e.i + 1 >= capacity) {
+    if (!(p = GrowEnviron(p))) {
+      return -1;
     }
   }
-  if (i + 1 >= capacity) {
-    GrowEnviron();
-  }
-  environ[i + 1] = 0;
-Replace:
-  __cxa_atexit(PutEnvImplAtExit, environ[i], 0);
-  environ[i] = s;
+  p[e.i + 1] = 0;
+  p[e.i] = s;
   return 0;
-Fail:
-  free(s);
-  return einval();
-}
-
-static void UnsetenvFree(void *p) {
-  free(p);
-}
-
-/* weakly called by unsetenv() when removing a pointer */
-void __freeenv(void *p) {
-  if (once) {
-    __cxa_atexit(UnsetenvFree, p, 0);
-  }
 }
 
 /**
  * Emplaces environment key=value.
  *
- * @return 0 on success or non-zero on error
+ * @param s should be a string that looks like `"name=value"` and it'll
+ *     become part of the environment; changes to its memory will change
+ *     the environment too
+ * @return 0 on success, or non-zero w/ errno on error
+ * @raise ENOMEM if we require more vespene gas
  * @see setenv(), getenv()
  */
 int putenv(char *s) {
   int rc;
-  rc = PutEnvImpl(strdup(s), true);
-  STRACE("putenv(%#s) → %d", s, rc);
+  rc = PutEnvImpl(s, true);
+  STRACE("putenv(%#s) → %d% m", s, rc);
   return rc;
 }

libc/intrin/setenv.c

@@ -16,10 +16,9 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/intrin/safemacros.internal.h"
+#include "libc/intrin/kmalloc.h"
 #include "libc/intrin/strace.internal.h"
 #include "libc/mem/internal.h"
-#include "libc/mem/mem.h"
 #include "libc/runtime/runtime.h"
 #include "libc/str/str.h"
 #include "libc/sysv/errfuns.h"
@@ -27,7 +26,7 @@
 /**
  * Copies variable to environment.
  *
- * @return 0 on success, or -1 w/ errno
+ * @return 0 on success, or -1 w/ errno and environment is unchanged
  * @raise EINVAL if `name` is empty or contains `'='`
  * @raise ENOMEM if we require more vespene gas
  * @see putenv(), getenv()
@@ -35,12 +34,16 @@
 int setenv(const char *name, const char *value, int overwrite) {
   int rc;
   char *s;
-  size_t namelen, valuelen;
-  if (isempty(name) || strchr(name, '=')) return einval();
-  namelen = strlen(name);
-  valuelen = strlen(value);
-  if (!(s = malloc(namelen + valuelen + 2))) return -1;
-  memcpy(mempcpy(mempcpy(s, name, namelen), "=", 1), value, valuelen + 1);
+  size_t n, m;
+  const char *t;
+  if (!name || !*name || !value) return einval();
+  for (t = name; *t; ++t) {
+    if (*t == '=') return einval();
+  }
+  n = strlen(name);
+  m = strlen(value);
+  if (!(s = kmalloc(n + 1 + m + 1))) return -1;
+  memcpy(mempcpy(mempcpy(s, name, n), "=", 1), value, m + 1);
   rc = PutEnvImpl(s, overwrite);
   STRACE("setenv(%#s, %#s, %d) → %d% m", name, value, overwrite, rc);
   return rc;

libc/intrin/sigaddset.c

@@ -17,6 +17,7 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/struct/sigset.h"
+#include "libc/sysv/consts/limits.h"
 #include "libc/sysv/consts/sig.h"
 #include "libc/sysv/errfuns.h"
 
@@ -28,10 +29,16 @@
  * @asyncsignalsafe
  */
 int sigaddset(sigset_t *set, int sig) {
+  _Static_assert(NSIG == sizeof(set->__bits) * CHAR_BIT, "");
   _Static_assert(sizeof(set->__bits[0]) * CHAR_BIT == 64, "");
   if (1 <= sig && sig <= NSIG) {
-    if (!sigisprecious(sig)) {
-      set->__bits[(sig - 1) >> 6] |= 1ull << ((sig - 1) & 63);
+    if (1 <= sig && sig <= _NSIG) {
+      if (
+#define M(x) sig != x &&
+#include "libc/intrin/sigisprecious.inc"
+          1) {
+        set->__bits[(sig - 1) >> 6] |= 1ull << ((sig - 1) & 63);
+      }
     }
     return 0;
   } else {

libc/intrin/sigcountset.c

@@ -19,6 +19,7 @@
 #include "libc/calls/struct/sigset.h"
 #include "libc/intrin/popcnt.h"
 #include "libc/macros.internal.h"
+#include "libc/sysv/consts/limits.h"
 
 /**
  * Returns population count of signal set.
@@ -27,9 +28,22 @@
  * @asyncsignalsafe
  */
 int sigcountset(const sigset_t *set) {
-  int r, i;
-  for (r = i = 0; i < ARRAYLEN(set->__bits); ++i) {
-    r += popcnt(set->__bits[i]);
+  int r, i, x, y;
+  switch (_NSIG) {
+    case 32:
+      x = (uint32_t)set->__bits[0];
+      y = 0;
+      break;
+    case 64:
+      x = set->__bits[0];
+      y = 0;
+      break;
+    case 128:
+      x = set->__bits[0];
+      y = set->__bits[1];
+      break;
+    default:
+      notpossible;
   }
-  return r;
+  return popcnt(x) + popcnt(y);
 }

libc/intrin/sigdelset.c

@@ -27,6 +27,7 @@
  * @asyncsignalsafe
  */
 int sigdelset(sigset_t *set, int sig) {
+  _Static_assert(NSIG == sizeof(set->__bits) * CHAR_BIT, "");
   _Static_assert(sizeof(set->__bits[0]) * CHAR_BIT == 64, "");
   if (1 <= sig && sig <= NSIG) {
     set->__bits[(sig - 1) >> 6] &= ~(1ull << ((sig - 1) & 63));

libc/intrin/sigfillset.c

@@ -18,6 +18,7 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/struct/sigset.h"
 #include "libc/str/str.h"
+#include "libc/sysv/consts/limits.h"
 #include "libc/sysv/consts/sig.h"
 
 /**
@@ -29,7 +30,17 @@
  */
 int sigfillset(sigset_t *set) {
   memset(set->__bits, -1, sizeof(set->__bits));
-  sigdelset(set, SIGKILL);
-  sigdelset(set, SIGSTOP);
+#define M(x) set->__bits[(x - 1) >> 6] &= ~(1ull << ((x - 1) & 63));
+#include "libc/intrin/sigisprecious.inc"
+  switch (_NSIG) {
+    case 32:
+      set->__bits[0] &= 0xffffffff;
+      break;
+    case 64:
+      set->__bits[1] = 0;
+      break;
+    default:
+      break;
+  }
   return 0;
 }

libc/intrin/sigismember.c

@@ -17,6 +17,7 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/struct/sigset.h"
+#include "libc/sysv/consts/limits.h"
 #include "libc/sysv/errfuns.h"
 
 /**
@@ -30,7 +31,11 @@
 int sigismember(const sigset_t *set, int sig) {
   _Static_assert(sizeof(set->__bits[0]) * CHAR_BIT == 64, "");
   if (1 <= sig && sig <= NSIG) {
-    return !!(set->__bits[(sig - 1) >> 6] & (1ull << ((sig - 1) & 63)));
+    if (1 <= sig && sig <= _NSIG) {
+      return !!(set->__bits[(sig - 1) >> 6] & (1ull << ((sig - 1) & 63)));
+    } else {
+      return 0;
+    }
   } else {
     return einval();
   }

libc/intrin/sigisprecious.c

@@ -23,6 +23,8 @@
  * Returns true if you're not authorized to block this signal.
  */
 int sigisprecious(int sig) {
-  return sig == SIGKILL ||  //
-         sig == SIGSTOP;
+  return 0
+#define M(x) || sig == x
+#include "libc/intrin/sigisprecious.inc"
+      ;
 }

libc/intrin/sigisprecious.inc

@@ -0,0 +1,3 @@
+M(SIGKILL)
+M(SIGABRT)
+M(SIGSTOP)

libc/intrin/strsignal_r.c

@@ -33,6 +33,7 @@
  * @param buf may be used to store output having at least 15 bytes
  * @return pointer to .rodata string, or to `buf` after mutating
  * @see sigaction()
+ * @asyncsignalsafe
  * @threadsafe
  */
 char *strsignal_r(int sig, char buf[hasatleast 15]) {

libc/intrin/unsetenv.c

@@ -17,39 +17,29 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/dce.h"
-#include "libc/intrin/weaken.h"
-#include "libc/mem/internal.h"
+#include "libc/intrin/_getenv.internal.h"
 #include "libc/runtime/runtime.h"
-
-#define ToUpper(c) \
-  (IsWindows() && (c) >= 'a' && (c) <= 'z' ? (c) - 'a' + 'A' : (c))
+#include "libc/sysv/errfuns.h"
 
 /**
  * Removes environment variable.
+ *
+ * @param s is non-empty environment key which can't contain `'='`
+ * @return 0 on success, or -1 w/ errno and environment is unchanged
+ * @raise EINVAL if `s` is an empty string or has a `'='` character
  */
 int unsetenv(const char *s) {
-  char **p;
-  size_t i, j, k;
-  if (s && (p = environ)) {
-    for (i = 0; p[i]; ++i) {
-      for (j = 0;; ++j) {
-        if (!s[j]) {
-          if (p[i][j] == '=') {
-            if (_weaken(__freeenv)) {
-              _weaken(__freeenv)(p[i]);
-            }
-            k = i + 1;
-            do {
-              p[k - 1] = p[k];
-            } while (p[k++]);
-            return 0;
-          }
-          break;
-        }
-        if (ToUpper(s[j]) != ToUpper(p[i][j])) {
-          break;
-        }
-      }
+  char **p, *t;
+  struct Env e;
+  if (!s || !*s) return einval();
+  for (t = s; *t; ++t) {
+    if (*t == '=') return einval();
+  }
+  if ((p = environ)) {
+    e = _getenv(p, s);
+    while (p[e.i]) {
+      p[e.i] = p[e.i + 1];
+      ++e.i;
     }
   }
   return 0;

libc/log/backtrace2.c

@@ -125,7 +125,7 @@ static int PrintBacktraceUsingAddr2line(int fd, const struct StackFrame *bp) {
   if (sys_pipe2(pipefds, O_CLOEXEC) == -1) {
     return -1;
   }
-  if ((pid = fork()) == -1) {
+  if ((pid = __sys_fork().ax) == -1) {
     sys_close(pipefds[0]);
     sys_close(pipefds[1]);
     return -1;
@@ -149,19 +149,12 @@ static int PrintBacktraceUsingAddr2line(int fd, const struct StackFrame *bp) {
     }
     p1 = buf;
     p3 = p1 + got;
-    /*
-     * remove racist output from gnu tooling, that can't be disabled
-     * otherwise, since it breaks other tools like emacs that aren't
-     * equipped to ignore it, and what's most problematic is that
-     * addr2line somehow manages to put the racism onto the one line
-     * in the backtrace we actually care about.
-     */
     for (got = p3 - buf, p1 = buf; got;) {
       if ((p2 = memmem(p1, got, " (discriminator ",
                        strlen(" (discriminator ") - 1)) &&
           (p3 = memchr(p2, '\n', got - (p2 - p1)))) {
         if (p3 > p2 && p3[-1] == '\r') --p3;
-        write(2, p1, p2 - p1);
+        sys_write(2, p1, p2 - p1);
         got -= p3 - p1;
         p1 += p3 - p1;
       } else {
@@ -183,11 +176,13 @@ static int PrintBacktraceUsingAddr2line(int fd, const struct StackFrame *bp) {
 }
 
 static int PrintBacktrace(int fd, const struct StackFrame *bp) {
+#if !defined(DWARFLESS)
   if (!IsTiny() && !__isworker) {
     if (PrintBacktraceUsingAddr2line(fd, bp) != -1) {
       return 0;
     }
   }
+#endif
   return PrintBacktraceUsingSymbols(fd, bp, GetSymbolTable());
 }
 

libc/log/backtrace3.c

@@ -83,7 +83,7 @@ noinstrument noasan int PrintBacktraceUsingSymbols(int fd,
     } else {
       addend = 0;
     }
-    kprintf("%012lx %012lx %s%+d\n", frame, addr, __get_symbol_name(st, symbol),
+    kprintf("%012lx %lx %s%+d\n", frame, addr, __get_symbol_name(st, symbol),
             addend);
   }
   return 0;

libc/log/log.mk

@@ -42,6 +42,7 @@ LIBC_LOG_A_DIRECTDEPS =					\
 	LIBC_SYSV_CALLS					\
 	LIBC_TIME					\
 	LIBC_TINYMATH					\
+	LIBC_ZIPOS					\
 	THIRD_PARTY_DLMALLOC				\
 	THIRD_PARTY_GDTOA
 

libc/log/showcrashreports.c

@@ -32,6 +32,7 @@
 #include "libc/sysv/consts/sig.h"
 #include "libc/sysv/consts/ss.h"
 
+STATIC_YOINK("zipos");                       // for symtab
 STATIC_YOINK("__die");                       // for backtracing
 STATIC_YOINK("ShowBacktrace");               // for backtracing
 STATIC_YOINK("GetSymbolTable");              // for backtracing

libc/log/vflogf.c

@@ -18,7 +18,6 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/calls.h"
 #include "libc/calls/dprintf.h"
-#include "libc/intrin/strace.internal.h"
 #include "libc/calls/struct/stat.h"
 #include "libc/calls/struct/timeval.h"
 #include "libc/dce.h"
@@ -27,6 +26,7 @@
 #include "libc/fmt/fmt.h"
 #include "libc/intrin/bits.h"
 #include "libc/intrin/safemacros.internal.h"
+#include "libc/intrin/strace.internal.h"
 #include "libc/log/internal.h"
 #include "libc/log/log.h"
 #include "libc/math.h"
@@ -131,7 +131,9 @@ void(vflogf)(unsigned level, const char *file, int line, FILE *f,
     __start_fatal(file, line);
     strcpy(buf32, "unknown");
     gethostname(buf32, sizeof(buf32));
-    (dprintf)(STDERR_FILENO, "fatality %s pid %d\n", buf32, getpid());
+    (dprintf)(STDERR_FILENO,
+              "exiting due to aforementioned error (host %s pid %d tid %d)\n",
+              buf32, getpid(), gettid());
     __die();
     unreachable;
   }

libc/mem/internal.h

@@ -10,7 +10,6 @@ struct CritbitNode {
 };
 
 int PutEnvImpl(char *, bool) hidden;
-void __freeenv(void *) hidden;
 
 COSMOPOLITAN_C_END_
 #endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */

libc/mem/sortedints.c

@@ -0,0 +1,93 @@
+/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
+│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
+╞══════════════════════════════════════════════════════════════════════════════╡
+│ Copyright 2022 Justine Alexandra Roberts Tunney                              │
+│                                                                              │
+│ Permission to use, copy, modify, and/or distribute this software for         │
+│ any purpose with or without fee is hereby granted, provided that the         │
+│ above copyright notice and this permission notice appear in all copies.      │
+│                                                                              │
+│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
+│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
+│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
+│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
+│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
+│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
+│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
+│ PERFORMANCE OF THIS SOFTWARE.                                                │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/assert.h"
+#include "libc/dce.h"
+#include "libc/intrin/midpoint.h"
+#include "libc/mem/mem.h"
+#include "libc/mem/sortedints.internal.h"
+#include "libc/str/str.h"
+
+bool ContainsInt(const struct SortedInts *t, int k) {
+  int l, m, r;
+  l = 0;
+  r = t->n - 1;
+  while (l <= r) {
+    m = _midpoint(l, r);
+    if (t->p[m] < k) {
+      l = m + 1;
+    } else if (t->p[m] > k) {
+      r = m - 1;
+    } else {
+      return true;
+    }
+  }
+  return false;
+}
+
+int LeftmostInt(const struct SortedInts *t, int k) {
+  int l, m, r;
+  l = 0;
+  r = t->n;
+  while (l < r) {
+    m = _midpoint(l, r);
+    if (t->p[m] < k) {
+      l = m + 1;
+    } else {
+      r = m;
+    }
+  }
+  _unassert(l == 0 || k >= t->p[l - 1]);
+  _unassert(l == t->n || k <= t->p[l]);
+  return l;
+}
+
+int CountInt(const struct SortedInts *t, int k) {
+  int i, c;
+  for (c = 0, i = LeftmostInt(t, k); i < t->n; ++i) {
+    if (t->p[i] == k) {
+      ++c;
+    } else {
+      break;
+    }
+  }
+  return c;
+}
+
+bool InsertInt(struct SortedInts *t, int k, bool u) {
+  int l;
+  _unassert(t->n >= 0);
+  _unassert(t->n <= t->c);
+  if (t->n == t->c) {
+    ++t->c;
+    if (!IsModeDbg()) {
+      t->c += t->c >> 1;
+    }
+    t->p = realloc(t->p, t->c * sizeof(*t->p));
+  }
+  l = LeftmostInt(t, k);
+  if (l < t->n) {
+    if (u && t->p[l] == k) {
+      return false;
+    }
+    memmove(t->p + l + 1, t->p + l, (t->n - l) * sizeof(*t->p));
+  }
+  t->p[l] = k;
+  t->n++;
+  return true;
+}

libc/mem/sortedints.internal.h

@@ -0,0 +1,19 @@
+#ifndef COSMOPOLITAN_LIBC_MEM_SORTEDINTS_INTERNAL_H_
+#define COSMOPOLITAN_LIBC_MEM_SORTEDINTS_INTERNAL_H_
+#if !(__ASSEMBLER__ + __LINKER__ + 0)
+COSMOPOLITAN_C_START_
+
+struct SortedInts {
+  int n;
+  int c;
+  int *p;
+};
+
+bool ContainsInt(const struct SortedInts *, int);
+bool InsertInt(struct SortedInts *, int, bool);
+int CountInt(const struct SortedInts *, int);
+int LeftmostInt(const struct SortedInts *, int);
+
+COSMOPOLITAN_C_END_
+#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
+#endif /* COSMOPOLITAN_LIBC_MEM_SORTEDINTS_INTERNAL_H_ */

libc/nexgen32e/longjmp.S

@@ -23,9 +23,8 @@
 //	@param	rdi points to the jmp_buf
 //	@param	esi is returned by setjmp() invocation (coerced nonzero)
 //	@noreturn
-//	@assume	system five nexgen32e abi conformant
-//	@note	code built w/ microsoft abi compiler can't call this
-//	@see	_gclongjmp() unwinds _gc() destructors
+//	@see	_gclongjmp()
+//	@see	siglongjmp()
 longjmp:
 	mov	%esi,%eax
 	test	%eax,%eax
@@ -41,4 +40,3 @@ longjmp:
 	jmp	*56(%rdi)
 	.endfn	longjmp,globl
 	.alias	longjmp,_longjmp
-	.alias	longjmp,siglongjmp

libc/nexgen32e/siglongjmp.S

@@ -1,7 +1,7 @@
-/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
-│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
+/*-*- mode:unix-assembly; indent-tabs-mode:t; tab-width:8; coding:utf-8     -*-│
+│vi: set et ft=asm ts=8 tw=8 fenc=utf-8                                     :vi│
 ╞══════════════════════════════════════════════════════════════════════════════╡
-│ Copyright 2021 Justine Alexandra Roberts Tunney                              │
+│ Copyright 2022 Justine Alexandra Roberts Tunney                              │
 │                                                                              │
 │ Permission to use, copy, modify, and/or distribute this software for         │
 │ any purpose with or without fee is hereby granted, provided that the         │
@@ -16,13 +16,14 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/calls/termios.h"
-#include "libc/sysv/consts/termios.h"
+#include "libc/macros.internal.h"
 
-uint32_t cfgetospeed(const struct termios *t) {
-  if (CBAUD) {
-    return t->c_cflag & CBAUD;
-  } else {
-    return t->c_ospeed;
-  }
-}
+//	Loads previously saved processor state.
+//
+//	@param	rdi points to the jmp_buf
+//	@param	esi is returned by setjmp() invocation (coerced nonzero)
+//	@noreturn
+//	@asyncsignalsafe
+siglongjmp:
+	jmp	longjmp
+	.endfn	siglongjmp,globl

libc/nt/comms.h

@@ -0,0 +1,36 @@
+#ifndef COSMOPOLITAN_LIBC_NT_COMMS_H_
+#define COSMOPOLITAN_LIBC_NT_COMMS_H_
+#if !(__ASSEMBLER__ + __LINKER__ + 0)
+COSMOPOLITAN_C_START_
+/*                            ░░░░
+                       ▒▒▒░░░▒▒▒▒▒▒▒▓▓▓░
+                      ▒▒▒▒░░░▒▒▒▒▒▒▓▓▓▓▓▓░
+                     ▒▒▒▒░░░▒▒▒▒▒▒▒▓▓▓▓▓▓  ▒▓░
+                     ▒▒▒░░░░▒▒▒▒▒▒▓▓▓▓▓▓   ▓▓▓▓▓▓▒        ▒▒▒▓▓█
+                    ▒▒▒▒░░░▒▒▒▒▒▒▒▓▓▓▓▓▓  ▓▓▓▓▓▓▓▓▒▒▒▒▒▒▒▒▒▒▓▓▓
+                   ░▒▒▒░░░░▒▒▒▒▒▒▓▓▓▓▓▓   █▓▓▓▓▓▓▓▒▒▒▒▒▒▒▒▒▒▓▓█
+                   ▒▒▒▒░░░▒▒▒▒▒▒▒▓▓▓▓▓░  ▓▓▓▓▓▓▓▓▒▒▒▒▒▒▒▒▒▒▓▓▓
+                  ▒▒▒▒░░░▒▒▒▒▒▒▒▓▓▓▓▓▓  ▒▓▓▓▓▓▓▓▓▒▒▒▒▒▒▒▒▒▒▓▓▒
+                  ▒▒▒▒▓▓      ▓▒▒▓▓▓▓   ▓▓▓▓▓▓▓▓▒▒▒▒▒▒▒▒▒▒▓▓█
+                                   ▒▓  ▓▓▓▓▓▓▓▓▓▒▒▒▒▒▒▒▒▒▒▓▓
+                  ░░░░░░░░░░░▒▒▒▒      ▓▓▓▓▓▓▓▓▒▒▒▒▒▒▒▒▒▒▓▓█
+                ▒▒░░░░░░░░░░▒▒▒▒▒▓▓▓     ▓▓▓▓▓▒▒▒▒▒▒▒▒▒▒▓▓▓
+               ░▒░░░░░░░░░░░▒▒▒▒▒▓▓   ▓░      ░▓███▓
+               ▒▒░░░░░░░░░░▒▒▒▒▒▓▓░  ▒▓▓▓▒▒▒         ░▒▒▒▓   ████████████
+              ▒▒░░░░░░░░░░░▒▒▒▒▒▓▓  ▒▓▓▓▓▒▒▒▒▒▒▒▒░░░▒▒▒▒▒░           ░███
+              ▒░░░░░░░░░░░▒▒▒▒▒▓▓   ▓▓▓▓▒▒▒▒▒▒▒▒░░░░▒▒▒▒▓            ███
+             ▒▒░░░░░░░░░░▒▒▒▒▒▒▓▓  ▒▓▓▓▒▒▒▒▒▒▒▒░░░░▒▒▒▒▒            ▓██
+             ▒░░░░░░░░░░░▒▒▒▒▒▓▓   ▓▓▓▓▒▒▒▒▒▒▒▒░░░▒▒▒▒▒▓           ▓██
+            ▒▒░░░▒▒▒░░░▒▒░▒▒▒▓▓▒  ▒▓▓▓▒▒▒▒▒▒▒▒░░░░▒▒▒▒▒           ███
+                            ░▒▓  ░▓▓▓▓▒▒▒▒▒▒▒▒░░░░▒▒▒▒▓          ▓██
+╔────────────────────────────────────────────────────────────────▀▀▀─────────│─╗
+│ cosmopolitan § new technology » communications                           ─╬─│┼
+╚────────────────────────────────────────────────────────────────────────────│*/
+
+bool32 PurgeComm(int64_t hFile, uint32_t dwFlags);
+bool32 TransmitCommChar(int64_t hFile, char cChar);
+bool32 ClearCommBreak(int64_t hFile);
+
+COSMOPOLITAN_C_END_
+#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
+#endif /* COSMOPOLITAN_LIBC_NT_COMMS_H_ */

libc/nt/kernel32/ClearCommBreak.s

@@ -1,2 +1,15 @@
 .include "o/libc/nt/codegen.inc"
 .imp	kernel32,__imp_ClearCommBreak,ClearCommBreak,0
+
+	.text.windows
+ClearCommBreak:
+	push	%rbp
+	mov	%rsp,%rbp
+	.profilable
+	mov	%rdi,%rcx
+	sub	$32,%rsp
+	call	*__imp_ClearCommBreak(%rip)
+	leave
+	ret
+	.endfn	ClearCommBreak,globl
+	.previous

libc/nt/kernel32/PurgeComm.s

@@ -1,2 +1,12 @@
 .include "o/libc/nt/codegen.inc"
 .imp	kernel32,__imp_PurgeComm,PurgeComm,0
+
+	.text.windows
+PurgeComm:
+	push	%rbp
+	mov	%rsp,%rbp
+	.profilable
+	mov	__imp_PurgeComm(%rip),%rax
+	jmp	__sysv2nt
+	.endfn	PurgeComm,globl
+	.previous

libc/nt/kernel32/TransmitCommChar.s

@@ -1,2 +1,12 @@
 .include "o/libc/nt/codegen.inc"
 .imp	kernel32,__imp_TransmitCommChar,TransmitCommChar,0
+
+	.text.windows
+TransmitCommChar:
+	push	%rbp
+	mov	%rsp,%rbp
+	.profilable
+	mov	__imp_TransmitCommChar(%rip),%rax
+	jmp	__sysv2nt
+	.endfn	TransmitCommChar,globl
+	.previous

libc/nt/master.sh

@@ -112,7 +112,7 @@ imp	'CheckNameLegalDOS8Dot3'				CheckNameLegalDOS8Dot3W					kernel32	128
 imp	'CheckRemoteDebuggerPresent'				CheckRemoteDebuggerPresent				kernel32	0	2
 imp	'CheckTokenCapability'					CheckTokenCapability					kernel32	0
 imp	'CheckTokenMembershipEx'				CheckTokenMembershipEx					kernel32	0
-imp	'ClearCommBreak'					ClearCommBreak						kernel32	0
+imp	'ClearCommBreak'					ClearCommBreak						kernel32	0	1
 imp	'ClearCommError'					ClearCommError						kernel32	0
 imp	'CloseConsoleHandle'					CloseConsoleHandle					kernel32	134
 imp	'ClosePackageInfo'					ClosePackageInfo					kernel32	0
@@ -764,7 +764,7 @@ imp	'PssWalkMarkerSetPosition'				PssWalkMarkerSetPosition				kernel32	0
 imp	'PssWalkMarkerTell'					PssWalkMarkerTell					kernel32	1080
 imp	'PssWalkSnapshot'					PssWalkSnapshot						kernel32	0
 imp	'PulseEvent'						PulseEvent						kernel32	0	1
-imp	'PurgeComm'						PurgeComm						kernel32	0
+imp	'PurgeComm'						PurgeComm						kernel32	0	2
 imp	'QueryActCtx'						QueryActCtxW						kernel32	0
 imp	'QueryActCtxSettings'					QueryActCtxSettingsW					kernel32	0
 imp	'QueryActCtxSettingsWWorker'				QueryActCtxSettingsWWorker				kernel32	1085
@@ -1011,7 +1011,7 @@ imp	'TlsGetValue'						TlsGetValue						kernel32	0	1
 imp	'TlsSetValue'						TlsSetValue						kernel32	0	2
 imp	'Toolhelp32ReadProcessMemory'				Toolhelp32ReadProcessMemory				kernel32	1449
 imp	'TransactNamedPipe'					TransactNamedPipe					kernel32	0	7
-imp	'TransmitCommChar'					TransmitCommChar					kernel32	0
+imp	'TransmitCommChar'					TransmitCommChar					kernel32	0	2
 imp	'TryAcquireSRWLockExclusive'				TryAcquireSRWLockExclusive				kernel32	0	1
 imp	'TryAcquireSRWLockShared'				TryAcquireSRWLockShared					kernel32	0	1
 imp	'TryEnterCriticalSection'				TryEnterCriticalSection					kernel32	0	1

libc/runtime/cocmd.c

@@ -25,6 +25,7 @@
 #include "libc/fmt/conv.h"
 #include "libc/fmt/itoa.h"
 #include "libc/fmt/magnumstrs.internal.h"
+#include "libc/intrin/_getenv.internal.h"
 #include "libc/intrin/bits.h"
 #include "libc/intrin/weaken.h"
 #include "libc/macros.internal.h"
@@ -55,11 +56,6 @@
 #define TOMBSTONE ((char *)-1)
 #define READ24(s) READ32LE(s "\0")
 
-struct Env {
-  char *s;
-  int i;
-};
-
 static char *p;
 static char *q;
 static char *r;
@@ -71,7 +67,7 @@ static char *assign;
 static char var[32];
 static int lastchild;
 static int exitstatus;
-static char *envs[3000];
+static char *envs[500];
 static char *args[3000];
 static const char *prog;
 static char errbuf[512];
@@ -148,27 +144,9 @@ static int GetSignalByName(const char *s) {
   return 0;
 }
 
-static struct Env GetEnv(char **p, const char *k) {
-  int i, j;
-  for (i = 0; p[i]; ++i) {
-    for (j = 0;; ++j) {
-      if (!k[j] || k[j] == '=') {
-        if (p[i][j] == '=') {
-          return (struct Env){p[i] + j + 1, i};
-        }
-        break;
-      }
-      if (toupper(k[j] & 255) != toupper(p[i][j] & 255)) {
-        break;
-      }
-    }
-  }
-  return (struct Env){0, i};
-}
-
 static void PutEnv(char **p, const char *kv) {
   struct Env e;
-  e = GetEnv(p, kv);
+  e = _getenv(p, kv);
   p[e.i] = kv;
   if (!e.s) p[e.i + 1] = 0;
 }
@@ -271,7 +249,7 @@ static int Read(void) {
 
 static int Cd(void) {
   const char *s;
-  if ((s = n > 1 ? args[1] : GetEnv(envs, "HOME").s)) {
+  if ((s = n > 1 ? args[1] : _getenv(envs, "HOME").s)) {
     if (!chdir(s)) {
       return 0;
     } else {
@@ -489,14 +467,27 @@ static const char *IntToStr(int x) {
 }
 
 static const char *GetVar(const char *key) {
+  static char vbuf[PATH_MAX];
   if (key[0] == '$' && !key[1]) {
     return IntToStr(getpid());
   } else if (key[0] == '!' && !key[1]) {
     return IntToStr(lastchild);
   } else if (key[0] == '?' && !key[1]) {
     return IntToStr(exitstatus);
+  } else if (!strcmp(key, "PWD")) {
+    _npassert(getcwd(vbuf, sizeof(vbuf)));
+    return vbuf;
+  } else if (!strcmp(key, "UID")) {
+    FormatInt32(vbuf, getuid());
+    return vbuf;
+  } else if (!strcmp(key, "GID")) {
+    FormatInt32(vbuf, getgid());
+    return vbuf;
+  } else if (!strcmp(key, "EUID")) {
+    FormatInt32(vbuf, geteuid());
+    return vbuf;
   } else {
-    return GetEnv(envs, key).s;
+    return _getenv(envs, key).s;
   }
 }
 

libc/runtime/enable_threads.c

@@ -19,8 +19,10 @@
 #include "ape/sections.internal.h"
 #include "libc/assert.h"
 #include "libc/calls/calls.h"
+#include "libc/calls/struct/sigset.h"
 #include "libc/calls/syscall-sysv.internal.h"
 #include "libc/intrin/strace.internal.h"
+#include "libc/runtime/morph.h"
 #include "libc/runtime/runtime.h"
 #include "libc/thread/tls.h"
 
@@ -30,7 +32,8 @@ extern int __threadcalls_start[];
 #pragma weak __threadcalls_end
 
 static privileged dontinline void FixupLockNops(void) {
-  __morph_begin();
+  sigset_t mask;
+  __morph_begin(&mask);
   /*
    * _NOPL("__threadcalls", func)
    *
@@ -54,7 +57,7 @@ static privileged dontinline void FixupLockNops(void) {
     _base[*p + 1] = 0x67;
     _base[*p + 2] = 0xe8;
   }
-  __morph_end();
+  __morph_end(&mask);
 }
 
 void __enable_threads(void) {

libc/runtime/enable_tls.c

@@ -19,6 +19,7 @@
 #include "ape/sections.internal.h"
 #include "libc/assert.h"
 #include "libc/calls/calls.h"
+#include "libc/calls/struct/sigset.h"
 #include "libc/calls/syscall-sysv.internal.h"
 #include "libc/dce.h"
 #include "libc/errno.h"
@@ -32,6 +33,7 @@
 #include "libc/nexgen32e/msr.h"
 #include "libc/nt/thread.h"
 #include "libc/runtime/internal.h"
+#include "libc/runtime/morph.h"
 #include "libc/runtime/runtime.h"
 #include "libc/stdalign.internal.h"
 #include "libc/str/str.h"
@@ -196,9 +198,10 @@ privileged void __enable_tls(void) {
   if ((intptr_t)_tls_content && (IsWindows() || IsXnu())) {
     int n;
     uint64_t w;
+    sigset_t mask;
     unsigned m, dis;
     unsigned char *p;
-    __morph_begin();
+    __morph_begin(&mask);
 
     if (IsXnu()) {
       // Apple is quite straightforward to patch. We basically
@@ -262,7 +265,7 @@ privileged void __enable_tls(void) {
       }
     }
 
-    __morph_end();
+    __morph_end(&mask);
   }
 
   // we are now allowed to use tls

libc/runtime/fork-nt.c

@@ -224,9 +224,6 @@ textwindows void WinMainForked(void) {
     AbortFork("CloseHandle");
   }
 
-  // turn tls back on
-  __enable_tls();
-
   // rewrap the stdin named pipe hack
   // since the handles closed on fork
   struct Fds *fds = VEIL("r", &g_fds);
@@ -267,11 +264,14 @@ textwindows int sys_fork_nt(uint32_t dwCreationFlags) {
   uint32_t oldprot;
   char **args, **args2;
   char16_t pipename[64];
+  bool needtls, threaded;
   int64_t reader, writer;
   struct NtStartupInfo startinfo;
   int i, n, pid, untrackpid, rc = -1;
   char *p, forkvar[6 + 21 + 1 + 21 + 1];
   struct NtProcessInformation procinfo;
+  threaded = __threaded;
+  needtls = __tls_enabled;
   if (!setjmp(jb)) {
     pid = untrackpid = __reservefd_unlocked(-1);
     reader = CreateNamedPipe(CreatePipeName(pipename),
@@ -345,9 +345,15 @@ textwindows int sys_fork_nt(uint32_t dwCreationFlags) {
     }
   } else {
     rc = 0;
+    if (needtls) {
+      __enable_tls();
+    }
+    if (threaded && !__threaded && _weaken(__enable_threads)) {
+      _weaken(__enable_threads)();
+    }
   }
   if (untrackpid != -1) {
-    __releasefd_unlocked(untrackpid);
+    __releasefd(untrackpid);
   }
   return rc;
 }

libc/runtime/fork-sysv.c

@@ -1,7 +1,7 @@
 /*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
 │vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
 ╞══════════════════════════════════════════════════════════════════════════════╡
-│ Copyright 2021 Justine Alexandra Roberts Tunney                              │
+│ Copyright 2022 Justine Alexandra Roberts Tunney                              │
 │                                                                              │
 │ Permission to use, copy, modify, and/or distribute this software for         │
 │ any purpose with or without fee is hereby granted, provided that the         │
@@ -16,13 +16,19 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/calls/termios.h"
-#include "libc/sysv/consts/termios.h"
+#include "libc/calls/syscall-sysv.internal.h"
+#include "libc/dce.h"
 
-uint32_t cfgetispeed(const struct termios *t) {
-  if (CBAUD) {
-    return t->c_cflag & CBAUD;
-  } else {
-    return t->c_ispeed;
+int sys_fork(void) {
+  axdx_t ad;
+  int ax, dx;
+  ad = __sys_fork();
+  ax = ad.ax;
+  dx = ad.dx;
+  if (IsXnu() && ax != -1) {
+    // eax always returned with childs pid
+    // edx is 0 for parent and 1 for child
+    ax &= dx - 1;
   }
+  return ax;
 }

libc/runtime/fork.c

@@ -17,6 +17,7 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/assert.h"
+#include "libc/calls/blocksigs.internal.h"
 #include "libc/calls/calls.h"
 #include "libc/calls/struct/sigset.h"
 #include "libc/calls/struct/sigset.internal.h"
@@ -33,30 +34,15 @@
 #include "libc/thread/tls.h"
 
 int _fork(uint32_t dwCreationFlags) {
-  axdx_t ad;
-  bool threaded;
-  sigset_t old, all;
   int ax, dx, parent;
-  sigfillset(&all);
-  _unassert(!sigprocmask(SIG_BLOCK, &all, &old));
+  BLOCK_SIGNALS;
   if (__threaded && _weaken(_pthread_onfork_prepare)) {
     _weaken(_pthread_onfork_prepare)();
   }
   if (!IsWindows()) {
-    ad = sys_fork();
-    ax = ad.ax;
-    dx = ad.dx;
-    if (IsXnu() && ax != -1) {
-      // eax always returned with childs pid
-      // edx is 0 for parent and 1 for child
-      ax &= dx - 1;
-    }
+    ax = sys_fork();
   } else {
-    threaded = __threaded;
     ax = sys_fork_nt(dwCreationFlags);
-    if (threaded && !__threaded && _weaken(__enable_threads)) {
-      _weaken(__enable_threads)();
-    }
   }
   if (!ax) {
     if (!IsWindows()) {
@@ -81,7 +67,7 @@ int _fork(uint32_t dwCreationFlags) {
     }
     STRACE("fork() → %d% m", ax);
   }
-  _unassert(!sigprocmask(SIG_SETMASK, &old, 0));
+  ALLOW_SIGNALS;
   return ax;
 }
 
@@ -92,6 +78,7 @@ int _fork(uint32_t dwCreationFlags) {
  * @raise EAGAIN if `RLIMIT_NPROC` was exceeded or system lacked resources
  * @raise ENOMEM if we require more vespene gas
  * @asyncsignalsafe
+ * @threadsafe
  */
 int fork(void) {
   return _fork(0);

libc/runtime/hook.greg.c

@@ -18,6 +18,7 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "ape/sections.internal.h"
 #include "libc/calls/struct/sigset.h"
+#include "libc/runtime/morph.h"
 #include "libc/runtime/runtime.h"
 #include "libc/runtime/symbols.internal.h"
 
@@ -45,13 +46,13 @@ privileged noinstrument noasan int __hook(void *ifunc,
   size_t i;
   char *p, *pe;
   intptr_t addr;
+  sigset_t mask;
   uint64_t code, mcode;
-  sigset_t mask, oldmask;
   intptr_t kMcount = (intptr_t)&mcount;
   intptr_t kProgramCodeStart = (intptr_t)_ereal;
   intptr_t kPrivilegedStart = (intptr_t)__privileged_addr;
   if (!symbols) return -1;
-  __morph_begin();
+  __morph_begin(&mask);
   for (i = 0; i < symbols->count; ++i) {
     if (symbols->addr_base + symbols->symbols[i].x < kProgramCodeStart) {
       continue;
@@ -112,6 +113,6 @@ privileged noinstrument noasan int __hook(void *ifunc,
       }
     }
   }
-  __morph_end();
+  __morph_end(&mask);
   return 0;
 }

libc/runtime/memtrack.internal.h

@@ -135,39 +135,39 @@ forceinline pureconst bool IsFixedFrame(int x) {
 }
 
 forceinline pureconst bool OverlapsImageSpace(const void *p, size_t n) {
-  const unsigned char *start, *ender;
+  const unsigned char *BegA, *EndA, *BegB, *EndB;
   if (n) {
-    start = p;
-    ender = start + (n - 1);
-    return ((_base <= start && start < _end) ||
-            (_base <= ender && ender < _end) ||
-            (start < _base && _end <= ender));
+    BegA = p;
+    EndA = BegA + (n - 1);
+    BegB = _base;
+    EndB = _end - 1;
+    return MAX(BegA, BegB) < MIN(EndA, EndB);
   } else {
     return 0;
   }
 }
 
 forceinline pureconst bool OverlapsArenaSpace(const void *p, size_t n) {
-  intptr_t x, y;
+  intptr_t BegA, EndA, BegB, EndB;
   if (n) {
-    x = (intptr_t)p;
-    y = x + (n - 1);
-    return ((0x50000000 <= x && x <= 0x7ffdffff) ||
-            (0x50000000 <= y && y <= 0x7ffdffff) ||
-            (x < 0x50000000 && 0x7ffdffff < y));
+    BegA = (intptr_t)p;
+    EndA = BegA + (n - 1);
+    BegB = 0x50000000;
+    EndB = 0x7ffdffff;
+    return MAX(BegA, BegB) < MIN(EndA, EndB);
   } else {
     return 0;
   }
 }
 
 forceinline pureconst bool OverlapsShadowSpace(const void *p, size_t n) {
-  intptr_t x, y;
+  intptr_t BegA, EndA, BegB, EndB;
   if (n) {
-    x = (intptr_t)p;
-    y = x + (n - 1);
-    return ((0x7fff0000 <= x && x <= 0x10007fffffff) ||
-            (0x7fff0000 <= y && y <= 0x10007fffffff) ||
-            (x < 0x7fff0000 && 0x10007fffffff < y));
+    BegA = (intptr_t)p;
+    EndA = BegA + (n - 1);
+    BegB = 0x7fff0000;
+    EndB = 0x10007fffffff;
+    return MAX(BegA, BegB) < MIN(EndA, EndB);
   } else {
     return 0;
   }

libc/runtime/morph.greg.c

@@ -18,6 +18,7 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #define ShouldUseMsabiAttribute() 1
 #include "ape/sections.internal.h"
+#include "libc/assert.h"
 #include "libc/calls/internal.h"
 #include "libc/calls/struct/sigset.h"
 #include "libc/dce.h"
@@ -37,9 +38,6 @@
 
 __msabi extern typeof(VirtualProtect) *const __imp_VirtualProtect;
 
-static int64_t vector;
-static sigset_t oldss;
-
 static privileged void __morph_mprotect(void *addr, size_t size, int prot,
                                         int ntprot) {
   bool cf;
@@ -58,7 +56,7 @@ static privileged void __morph_mprotect(void *addr, size_t size, int prot,
       _Exit(26);
     }
 #endif
-    if (ax) notpossible;
+    _npassert(!ax);
   } else {
     __imp_VirtualProtect(addr, size, ntprot, &op);
   }
@@ -69,29 +67,26 @@ static privileged void __morph_mprotect(void *addr, size_t size, int prot,
  *
  * @return 0 on success, or -1 w/ errno
  */
-privileged void __morph_begin(void) {
+privileged void __morph_begin(sigset_t *save) {
   int ax;
   bool cf;
   intptr_t dx;
   sigset_t ss = {{-1, -1}};
   STRACE("__morph_begin()");
-  if (!IsWindows()) {
-    if (!IsOpenbsd()) {
-      asm volatile("mov\t$8,%%r10d\n\t"
-                   "syscall"
-                   : "=a"(ax), "=d"(dx)
-                   : "0"(__NR_sigprocmask), "D"(SIG_BLOCK), "S"(&ss),
-                     "1"(&oldss)
-                   : "rcx", "r8", "r9", "r10", "r11", "memory", "cc");
-      if (ax) notpossible;
-    } else {
-      asm volatile(CFLAG_ASM("syscall")
-                   : CFLAG_CONSTRAINT(cf), "=a"(ax), "=d"(dx)
-                   : "1"(__NR_sigprocmask), "D"(SIG_BLOCK), "S"(-1u)
-                   : "rcx", "r8", "r9", "r10", "r11", "memory");
-      oldss.__bits[0] = ax & 0xffffffff;
-      if (cf) notpossible;
-    }
+  if (IsOpenbsd()) {
+    asm volatile(CFLAG_ASM("syscall")
+                 : CFLAG_CONSTRAINT(cf), "=a"(ax), "=d"(dx)
+                 : "1"(__NR_sigprocmask), "D"(SIG_BLOCK), "S"(-1u)
+                 : "rcx", "r8", "r9", "r10", "r11", "memory");
+    save->__bits[0] = ax & 0xffffffff;
+    _npassert(!cf);
+  } else if (!IsWindows() && !IsMetal()) {
+    asm volatile("mov\t$8,%%r10d\n\t"
+                 "syscall"
+                 : "=a"(ax), "=d"(dx)
+                 : "0"(__NR_sigprocmask), "D"(SIG_BLOCK), "S"(&ss), "1"(save)
+                 : "rcx", "r8", "r9", "r10", "r11", "memory", "cc");
+    _npassert(!ax);
   }
   __morph_mprotect(_base, __privileged_addr - _base, PROT_READ | PROT_WRITE,
                    kNtPageWritecopy);
@@ -100,29 +95,25 @@ privileged void __morph_begin(void) {
 /**
  * Begins code morphing executable.
  */
-privileged void __morph_end(void) {
+privileged void __morph_end(sigset_t *save) {
   int ax;
   long dx;
   bool cf;
   __morph_mprotect(_base, __privileged_addr - _base, PROT_READ | PROT_EXEC,
                    kNtPageExecuteRead);
-  if (!IsWindows()) {
-    if (!IsOpenbsd()) {
-      asm volatile("mov\t$8,%%r10d\n\t"
-                   "syscall"
-                   : "=a"(ax), "=d"(dx)
-                   : "0"(__NR_sigprocmask), "D"(SIG_SETMASK), "S"(&oldss),
-                     "1"(0)
-                   : "rcx", "r8", "r9", "r10", "r11", "memory", "cc");
-      if (ax) notpossible;
-    } else {
-      asm volatile(CFLAG_ASM("syscall")
-                   : CFLAG_CONSTRAINT(cf), "=a"(ax), "=d"(dx)
-                   : "1"(__NR_sigprocmask), "D"(SIG_SETMASK),
-                     "S"(oldss.__bits[0])
-                   : "rcx", "r8", "r9", "r10", "r11", "memory");
-      if (cf) notpossible;
-    }
+  if (IsOpenbsd()) {
+    asm volatile(CFLAG_ASM("syscall")
+                 : CFLAG_CONSTRAINT(cf), "=a"(ax), "=d"(dx)
+                 : "1"(__NR_sigprocmask), "D"(SIG_SETMASK), "S"(save->__bits[0])
+                 : "rcx", "r8", "r9", "r10", "r11", "memory");
+    _npassert(!cf);
+  } else if (!IsWindows() && !IsMetal()) {
+    asm volatile("mov\t$8,%%r10d\n\t"
+                 "syscall"
+                 : "=a"(ax), "=d"(dx)
+                 : "0"(__NR_sigprocmask), "D"(SIG_SETMASK), "S"(save), "1"(0)
+                 : "rcx", "r8", "r9", "r10", "r11", "memory", "cc");
+    _npassert(!ax);
   }
   STRACE("__morph_end()");
 }

libc/runtime/morph.h

@@ -0,0 +1,12 @@
+#ifndef COSMOPOLITAN_LIBC_RUNTIME_MORPH_H_
+#define COSMOPOLITAN_LIBC_RUNTIME_MORPH_H_
+#include "libc/calls/struct/sigset.h"
+#if !(__ASSEMBLER__ + __LINKER__ + 0)
+COSMOPOLITAN_C_START_
+
+void __morph_begin(sigset_t *);
+void __morph_end(sigset_t *);
+
+COSMOPOLITAN_C_END_
+#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
+#endif /* COSMOPOLITAN_LIBC_RUNTIME_MORPH_H_ */

libc/runtime/runtime.h

@@ -57,7 +57,7 @@ int atfork(void *, void *) libcesque;
 int atexit(void (*)(void)) libcesque;
 char *getenv(const char *) nosideeffect libcesque;
 int putenv(char *) paramsnonnull();
-int setenv(const char *, const char *, int) paramsnonnull();
+int setenv(const char *, const char *, int);
 int unsetenv(const char *);
 int clearenv(void);
 void fpreset(void);
@@ -100,8 +100,6 @@ char *GetInterpreterExecutableName(char *, size_t);
 void __printargs(const char *);
 void __paginate(int, const char *);
 int __arg_max(void);
-void __morph_begin(void);
-void __morph_end(void);
 void __print_maps(void);
 void __warn_if_powersave(void);
 const char *__describe_os(void);

libc/runtime/straceinit.greg.c

@@ -16,6 +16,8 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/dce.h"
+#include "libc/intrin/atomic.h"
 #include "libc/intrin/safemacros.internal.h"
 #include "libc/intrin/strace.internal.h"
 #include "libc/log/libfatal.internal.h"
@@ -29,7 +31,7 @@ textstartup int __strace_init(int argc, char **argv, char **envp, long *auxv) {
   /* asan isn't initialized yet at runlevel 300 */
   if (__intercept_flag(&argc, argv, "--strace") ||
       __atoul(nulltoempty(__getenv(envp, "STRACE")))) {
-    ++__strace;
+    atomic_store_explicit(&__strace, 1, memory_order_relaxed);
   }
   return (__argc = argc);
 }

libc/runtime/vfork.S

@@ -20,7 +20,6 @@
 #include "libc/intrin/strace.internal.h"
 #include "libc/thread/tls.h"
 #include "libc/macros.internal.h"
-.privileged
 
 //	Forks process without copying page tables.
 //
@@ -32,37 +31,55 @@
 //	do anything in a vfork()'d child process. TLS memory must not
 //	be disabled (it's enabled by default) since vfork() needs it.
 //
+//	What makes vfork() dangerous is that any changes to memory in
+//	the child process can happen in the parent too. The exception
+//	to this rule is `errno` which is saved/restored in a register
+//	by this implementation. However, despite its dangers, vfork's
+//	performance is irresistible and wonderous to behold. If safer
+//	code is desired, consider posix_spawn() which uses vfork().
+//
 //	Do not make the assumption that the parent is suspended until
-//	the child terminates since this impl calls fork() on Windows,
-//	OpenBSD, and MacOS.
+//	the child terminates since this uses the raw fork system call
+//	on Windows, OpenBSD, and MacOS. In that case the process will
+//	proceed without blocking the parent; however, the `__vforked`
+//	variable is still set to true in the child, so lock functions
+//	won't do anything, and other functions shall change behavior.
+//	This ensures that, even if the operating system does not give
+//	us the performance of vfork(), we'll still be able to cut out
+//	the libc overhead, e.g. pthread_atfork().
 //
 //	@return	pid of child process or 0 if forked process
 //	@returnstwice
 //	@threadsafe
 //	@vforksafe
-vfork:	call	__require_tls
-	xor	%edi,%edi		# dwCreationFlags
-#ifdef __SANITIZE_ADDRESS__
-	jmp	fork			# TODO: asan and vfork don't mix?
-	.endfn	vfork,globl
-#else
-#if SupportsWindows()
-	testb	IsWindows()
-	jnz	sys_fork_nt		# and we're lucky to have that
-#endif
-#if SupportsXnu()
-	testb	IsXnu()
-	jnz	fork
-#endif
-#if SupportsOpenbsd()
-	testb	IsOpenbsd()
-	jnz	fork			# fake vfork plus msyscall issues
-#endif
+vfork:
+#if !IsTiny()
+	push	%rbp
+	mov	%rsp,%rbp
+	.profilable
+	call	__require_tls
 #ifdef SYSDEBUG
 	ezlea	.Llog,di
 	call	__stracef
-#endif /* SYSDEBUG */
+#endif
+	pop	%rbp
+#endif
 	mov	%fs:0,%r9		# get thread information block
+#if SupportsWindows()
+	testb	IsWindows()
+	jnz	6f			# and we're lucky to have that
+#endif
+#ifdef __SANITIZE_ADDRESS__
+	jmp	5f			# TODO: asan and vfork don't mix?
+#endif
+#if SupportsXnu()
+	testb	IsXnu()
+	jnz	5f
+#endif
+#if SupportsOpenbsd()
+	testb	IsOpenbsd()
+	jnz	5f			# fake vfork plus msyscall issues
+#endif
 	mov	0x3c(%r9),%r8d		# avoid question of @vforksafe errno
 	pop	%rsi			# saves return address in a register
 	mov	__NR_vfork(%rip),%eax
@@ -79,12 +96,35 @@ vfork:	call	__require_tls
 	cmp	$-4095,%eax
 	jae	systemfive_error
 	mov	%r8d,0x3c(%r9)		# restore errno
-	test	%eax,%eax
-	jnz	.Lprnt
-.Lchld:	orb	$TIB_FLAG_VFORKED,0x40(%r9)
+1:	test	%eax,%eax
+	jnz	.Lpar
+.Lchi:	orb	$TIB_FLAG_VFORKED,0x40(%r9)
 	ret
-.Lprnt:	andb	$~TIB_FLAG_VFORKED,0x40(%r9)
+.Lpar:	andb	$~TIB_FLAG_VFORKED,0x40(%r9)
 	ret
+#if SupportsXnu() || SupportsOpenbsd() || defined(__SANITIZE_ADDRESS__)
+5:	push	%rbp
+	mov	%rsp,%rbp
+	push	%r9
+	push	%r9
+	call	sys_fork
+	pop	%r9
+	pop	%r9
+	pop	%rbp
+	jmp	1b
+#endif
+#if SupportsWindows()
+6:	push	%rbp
+	mov	%rsp,%rbp
+	push	%r9
+	push	%r9
+	xor	%edi,%edi		# dwCreationFlags
+	call	sys_fork_nt
+	pop	%r9
+	pop	%r9
+	pop	%rbp
+	jmp	1b
+#endif
 	.endfn	vfork,globl
 
 #ifdef SYSDEBUG
@@ -93,5 +133,3 @@ vfork:	call	__require_tls
 	.asciz	"vfork()\n"
 	.previous
 #endif /* DEBUGSYS */
-
-#endif /* __SANITIZE_ADDRESS__ */

libc/sock/socketpair-nt.c

@@ -95,8 +95,8 @@ textwindows int sys_socketpair_nt(int family, int type, int proto, int sv[2]) {
     rc = 0;
   } else {
     CloseHandle(hpipe);
-    __releasefd_unlocked(writer);
-    __releasefd_unlocked(reader);
+    __releasefd(writer);
+    __releasefd(reader);
     rc = -1;
   }