Fix bugs and make code tinier

- Fixed bug where stdio eof wasn't being sticky
- Fixed bug where fseeko() wasn't clearing eof state
- Removed assert() usage from libc favoring _unassert() / _npassert()

libc/intrin/cxaatexit.c

@@ -61,7 +61,7 @@ noasan int __cxa_atexit(void *fp, void *arg, void *pred) {
     }
   }
   i = _bsr(~b->mask);
-  assert(i < ARRAYLEN(b->p));
+  _unassert(i < ARRAYLEN(b->p));
   b->mask |= 1u << i;
   b->p[i].fp = fp;
   b->p[i].arg = arg;

libc/intrin/cxafinalize.c

@@ -60,7 +60,7 @@ StartOverLocked:
       if (!pred) {
         b2 = b->next;
         if (b2) {
-          assert(b != &__cxa_blocks.root);
+          _npassert(b != &__cxa_blocks.root);
           if (_weaken(free)) {
             _weaken(free)(b);
           }

libc/intrin/describeflags.internal.h

@@ -56,6 +56,7 @@ const char *DescribeSockOptname(char[32], int, int);
 const char *DescribeSocketFamily(char[12], int);
 const char *DescribeSocketProtocol(char[12], int);
 const char *DescribeSocketType(char[64], int);
+const char *DescribeStdioState(char[12], int);
 const char *DescribeWhence(char[12], int);
 
 #define DescribeArchPrctlCode(x)     DescribeArchPrctlCode(alloca(12), x)
@@ -99,6 +100,7 @@ const char *DescribeWhence(char[12], int);
 #define DescribeSocketFamily(x)      DescribeSocketFamily(alloca(12), x)
 #define DescribeSocketProtocol(x)    DescribeSocketProtocol(alloca(12), x)
 #define DescribeSocketType(x)        DescribeSocketType(alloca(64), x)
+#define DescribeStdioState(x)        DescribeStdioState(alloca(12), x)
 #define DescribeWhence(x)            DescribeWhence(alloca(12), x)
 
 COSMOPOLITAN_C_END_

libc/intrin/describeopenflags.c

@@ -34,10 +34,7 @@ const char *(DescribeOpenFlags)(char buf[128], int x) {
   struct DescribeFlags d[N];
   // TODO(jart): unify DescribeFlags and MagnumStr data structures
   for (n = 0; kOpenFlags[n].x != MAGNUM_TERMINATOR; ++n) {
-    if (n == N) {
-      assert(!"too many open flags");
-      break;
-    }
+    if (n == N) notpossible;
   }
   for (i = 0; i < n; ++i) {
     d[i].flag = MAGNUM_NUMBER(kOpenFlags, i);

libc/intrin/describestdiostate.c

@@ -0,0 +1,29 @@
+/*-*- 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/fmt/itoa.h"
+#include "libc/intrin/describeflags.internal.h"
+#include "libc/str/str.h"
+
+const char *(DescribeStdioState)(char buf[12], int x) {
+  if (!x) return "";
+  if (x == -1) return "EOF";
+  if (x > 0) return _strerrno(x);
+  FormatInt32(buf, x);
+  return buf;
+}

libc/intrin/directmap-nt.c

@@ -74,7 +74,7 @@ textwindows struct DirectMap sys_mmap_nt(void *addr, size_t size, int prot,
       }
     }
   } else {
-    assert(flags & MAP_ANONYMOUS);
+    _unassert(flags & MAP_ANONYMOUS);
     fl = (struct ProtectNt){kNtPageExecuteReadwrite,
                             kNtFileMapWrite | kNtFileMapExecute};
   }

libc/intrin/isatleastwindows10.greg.c

@@ -26,6 +26,6 @@
  * This function may only be called if IsWindows() is true.
  */
 privileged bool(IsAtLeastWindows10)(void) {
-  assert(IsWindows());
+  _unassert(IsWindows());
   return IsAtLeastWindows10();
 }

libc/intrin/midpoint.h

@@ -13,8 +13,8 @@
   ({                            \
     typeof((a) + (b)) a_ = (a); \
     typeof(a_) b_ = (b);        \
-    assert(a_ >= 0);            \
-    assert(b_ >= 0);            \
+    _unassert(a_ >= 0);         \
+    _unassert(b_ >= 0);         \
     asm("add\t%1,%0\n\t"        \
         "rcr\t%0"               \
         : "+r"(a_)              \

libc/intrin/pthread_once.c

@@ -56,14 +56,14 @@ errno_t pthread_once(pthread_once_t *once, void init(void)) {
                                                   memory_order_acquire,
                                                   memory_order_relaxed)) {
         init();
-        atomic_store(&once->_lock, FINISHED);
+        atomic_store_explicit(&once->_lock, FINISHED, memory_order_release);
         return 0;
       }
       // fallthrough
     case CALLING:
       do {
         pthread_yield();
-      } while (atomic_load_explicit(&once->_lock, memory_order_relaxed) ==
+      } while (atomic_load_explicit(&once->_lock, memory_order_acquire) ==
                CALLING);
       return 0;
     case FINISHED:

libc/intrin/strace.internal.h

@@ -3,10 +3,11 @@
 #include "libc/intrin/likely.h"
 #include "libc/runtime/runtime.h"
 
-#define _KERNTRACE 0 /* not configurable w/ flag yet */
-#define _POLLTRACE 0 /* not configurable w/ flag yet */
-#define _DATATRACE 1 /* not configurable w/ flag yet */
-#define _NTTRACE   0 /* not configurable w/ flag yet */
+#define _KERNTRACE  0 /* not configurable w/ flag yet */
+#define _POLLTRACE  0 /* not configurable w/ flag yet */
+#define _DATATRACE  1 /* not configurable w/ flag yet */
+#define _STDIOTRACE 0 /* not configurable w/ flag yet */
+#define _NTTRACE    0 /* not configurable w/ flag yet */
 
 #define STRACE_PROLOGUE "%rSYS %6P %'18T "
 
@@ -42,6 +43,12 @@ COSMOPOLITAN_C_START_
 #define KERNTRACE(FMT, ...) (void)0
 #endif
 
+#if defined(SYSDEBUG) && _STDIOTRACE
+#define STDIOTRACE(FMT, ...) STRACE(FMT, ##__VA_ARGS__)
+#else
+#define STDIOTRACE(FMT, ...) (void)0
+#endif
+
 #if defined(SYSDEBUG) && _NTTRACE
 #define NTTRACE(FMT, ...) STRACE(FMT, ##__VA_ARGS__)
 #else