Don't relocate file descriptor memory

This change fixes #496 where ASAN spotted a race condition that could
happen in multithreaded programs, with more than OPEN_MAX descriptors
when using ZipOS or Windows NT, which require tracking open file info
and this change fixes that table so it never relocates, thus allowing
us to continue to enjoy the benefits of avoiding locks while reading.

test/libc/calls/reservefd_test.c

@@ -61,7 +61,6 @@ void PullSomeZipFilesIntoLinkage(void) {
 TEST(reservefd, testGrowthOfFdsDataStructure) {
   int i, n;
   struct rlimit rlim;
-  ASSERT_EQ(g_fds.n, OPEN_MAX);
   n = 1700;  // pe '2**16/40' → 1638 (likely value of g_fds.n)
   if (!getrlimit(RLIMIT_NOFILE, &rlim)) n = MIN(n, rlim.rlim_cur - 3);
   for (i = 0; i < n; ++i) {

test/libc/test.mk

@@ -19,4 +19,5 @@ o/$(MODE)/test/libc:					\
 		o/$(MODE)/test/libc/time		\
 		o/$(MODE)/test/libc/tinymath		\
 		o/$(MODE)/test/libc/x			\
+		o/$(MODE)/test/libc/zipos		\
 		o/$(MODE)/test/libc/xed

test/libc/thread/pthread_create_test.c

@@ -26,6 +26,7 @@
 #include "libc/intrin/pthread2.h"
 #include "libc/macros.internal.h"
 #include "libc/mem/mem.h"
+#include "libc/nexgen32e/nexgen32e.h"
 #include "libc/runtime/runtime.h"
 #include "libc/runtime/stack.h"
 #include "libc/sysv/consts/prot.h"
@@ -37,18 +38,19 @@
 #include "libc/testlib/testlib.h"
 #include "libc/thread/thread.h"
 
-void OnTrap(int sig, struct siginfo *si, void *vctx) {
+void OnUsr1(int sig, struct siginfo *si, void *vctx) {
   struct ucontext *ctx = vctx;
 }
 
 void SetUp(void) {
-  struct sigaction sig = {.sa_sigaction = OnTrap, .sa_flags = SA_SIGINFO};
-  sigaction(SIGTRAP, &sig, 0);
+  struct sigaction sig = {.sa_sigaction = OnUsr1, .sa_flags = SA_SIGINFO};
+  sigaction(SIGUSR1, &sig, 0);
 }
 
 void TriggerSignal(void) {
   sched_yield();
-  DebugBreak();
+  /* kprintf("raising at %p\n", __builtin_frame_address(0)); */
+  raise(SIGUSR1);
   sched_yield();
 }
 
@@ -67,6 +69,7 @@ TEST(pthread_create, testCreateReturnJoin) {
 }
 
 static void *IncExit(void *arg) {
+  CheckStackIsAligned();
   TriggerSignal();
   pthread_exit((void *)((uintptr_t)arg + 1));
 }

test/libc/zipos/open_test.c

@@ -0,0 +1,56 @@
+/*-*- 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/calls/calls.h"
+#include "libc/mem/mem.h"
+#include "libc/runtime/gc.h"
+#include "libc/runtime/runtime.h"
+#include "libc/str/str.h"
+#include "libc/sysv/consts/o.h"
+#include "libc/testlib/hyperion.h"
+#include "libc/testlib/testlib.h"
+#include "libc/thread/spawn.h"
+#include "libc/zipos/zipos.h"
+
+STATIC_YOINK("zip_uri_support");
+STATIC_YOINK("libc/testlib/hyperion.txt");
+/* STATIC_YOINK("inflate"); */
+/* STATIC_YOINK("inflateInit2"); */
+/* STATIC_YOINK("inflateEnd"); */
+
+int Worker(void *arg, int tid) {
+  int i, fd;
+  char *data;
+  for (i = 0; i < 20; ++i) {
+    ASSERT_NE(-1, (fd = open("/zip/libc/testlib/hyperion.txt", O_RDONLY)));
+    data = malloc(kHyperionSize);
+    ASSERT_EQ(kHyperionSize, read(fd, data, kHyperionSize));
+    ASSERT_EQ(0, memcmp(data, kHyperion, kHyperionSize));
+    ASSERT_SYS(0, 0, close(fd));
+    free(data);
+  }
+  return 0;
+}
+
+TEST(zipos, test) {
+  int i, n = 16;
+  struct spawn *t = _gc(malloc(sizeof(struct spawn) * n));
+  for (i = 0; i < n; ++i) ASSERT_SYS(0, 0, _spawn(Worker, 0, t + i));
+  for (i = 0; i < n; ++i) EXPECT_SYS(0, 0, _join(t + i));
+  /* __print_maps(); */
+}

test/libc/zipos/test.mk

@@ -0,0 +1,63 @@
+#-*-mode:makefile-gmake;indent-tabs-mode:t;tab-width:8;coding:utf-8-*-┐
+#───vi: set et ft=make ts=8 tw=8 fenc=utf-8 :vi───────────────────────┘
+
+PKGS += TEST_LIBC_ZIPOS
+
+TEST_LIBC_ZIPOS_SRCS := $(wildcard test/libc/zipos/*.c)
+TEST_LIBC_ZIPOS_SRCS_TEST = $(filter %_test.c,$(TEST_LIBC_ZIPOS_SRCS))
+
+TEST_LIBC_ZIPOS_OBJS =						\
+	$(TEST_LIBC_ZIPOS_SRCS:%.c=o/$(MODE)/%.o)
+
+TEST_LIBC_ZIPOS_COMS =						\
+	$(TEST_LIBC_ZIPOS_SRCS:%.c=o/$(MODE)/%.com)
+
+TEST_LIBC_ZIPOS_BINS =						\
+	$(TEST_LIBC_ZIPOS_COMS)					\
+	$(TEST_LIBC_ZIPOS_COMS:%=%.dbg)
+
+TEST_LIBC_ZIPOS_TESTS =						\
+	$(TEST_LIBC_ZIPOS_SRCS_TEST:%.c=o/$(MODE)/%.com.ok)
+
+TEST_LIBC_ZIPOS_CHECKS =					\
+	$(TEST_LIBC_ZIPOS_SRCS_TEST:%.c=o/$(MODE)/%.com.runs)
+
+TEST_LIBC_ZIPOS_DIRECTDEPS =					\
+	LIBC_CALLS						\
+	LIBC_FMT						\
+	LIBC_INTRIN						\
+	LIBC_MEM						\
+	LIBC_NEXGEN32E						\
+	LIBC_RUNTIME						\
+	LIBC_STR						\
+	LIBC_STUBS						\
+	LIBC_THREAD						\
+	LIBC_SYSV						\
+	LIBC_ZIPOS						\
+	LIBC_TIME						\
+	LIBC_TESTLIB						\
+	THIRD_PARTY_ZLIB
+
+TEST_LIBC_ZIPOS_DEPS :=						\
+	$(call uniq,$(foreach x,$(TEST_LIBC_ZIPOS_DIRECTDEPS),$($(x))))
+
+o/$(MODE)/test/libc/zipos/zipos.pkg:				\
+		$(TEST_LIBC_ZIPOS_OBJS)				\
+		$(foreach x,$(TEST_LIBC_ZIPOS_DIRECTDEPS),$($(x)_A).pkg)
+
+#o/$(MODE)/libc/testlib/hyperion.txt.zip.o: private ZIPOBJ_FLAGS += -0
+
+o/$(MODE)/test/libc/zipos/%.com.dbg:				\
+		$(TEST_LIBC_ZIPOS_DEPS)				\
+		o/$(MODE)/test/libc/zipos/%.o			\
+		o/$(MODE)/test/libc/zipos/zipos.pkg		\
+		o/$(MODE)/libc/testlib/hyperion.txt.zip.o	\
+		$(LIBC_TESTMAIN)				\
+		$(CRT)						\
+		$(APE_NO_MODIFY_SELF)
+	@$(APELINK)
+
+.PHONY: o/$(MODE)/test/libc/zipos
+o/$(MODE)/test/libc/zipos:					\
+		$(TEST_LIBC_ZIPOS_BINS)				\
+		$(TEST_LIBC_ZIPOS_CHECKS)