Improve system calls

- Wrap clock_getres()
- Wrap sched_setscheduler()
- Make sleep() api conformant
- Polyfill sleep() using select()
- Improve clock_gettime() polyfill
- Make nanosleep() POSIX conformant
- Slightly improve some DNS functions
- Further strengthen pledge() sandboxing
- Improve rounding of timeval / timespec
- Allow layering of pledge() calls on Linux
- Polyfill sched_yield() using select() on XNU
- Delete more system constants we probably don't need

libc/testlib/showerror.c

@@ -16,11 +16,11 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/bits/atomic.h"
 #include "libc/bits/safemacros.internal.h"
 #include "libc/calls/calls.h"
 #include "libc/fmt/fmt.h"
 #include "libc/intrin/kprintf.h"
-#include "libc/intrin/spinlock.h"
 #include "libc/log/color.internal.h"
 #include "libc/log/internal.h"
 #include "libc/log/libfatal.internal.h"
@@ -32,16 +32,12 @@ const char *testlib_showerror_func;
 const char *testlib_showerror_isfatal;
 const char *testlib_showerror_macro;
 const char *testlib_showerror_symbol;
-_Alignas(64) static char testlib_showerror_lock;
 
 testonly void testlib_showerror(const char *file, int line, const char *func,
                                 const char *method, const char *symbol,
                                 const char *code, char *v1, char *v2) {
   char *p;
   char hostname[128];
-  _spinlock(&testlib_showerror_lock);
-  if (!IsWindows()) __getpid(); /* make strace easier to read */
-  if (!IsWindows()) __getpid();
   __stpcpy(hostname, "unknown");
   gethostname(hostname, sizeof(hostname));
   kprintf("%serror%s%s:%s:%d%s: %s() in %s(%s) on %s pid %d tid %d\n"
@@ -55,7 +51,6 @@ testonly void testlib_showerror(const char *file, int line, const char *func,
           SUBTLE, strerror(errno), GetProgramExecutableName(), RESET);
   free_s(&v1);
   free_s(&v2);
-  _spunlock(&testlib_showerror_lock);
 }
 
 /* TODO(jart): Pay off tech debt re duplication */
@@ -65,10 +60,7 @@ testonly void testlib_showerror_(int line, const char *wantcode,
   int e;
   va_list va;
   char hostname[128];
-  _spinlock(&testlib_showerror_lock);
   e = errno;
-  if (!IsWindows()) __getpid();
-  if (!IsWindows()) __getpid();
   if (gethostname(hostname, sizeof(hostname))) {
     __stpcpy(hostname, "unknown");
   }
@@ -98,6 +90,7 @@ testonly void testlib_showerror_(int line, const char *wantcode,
   free_s(&FREED_want);
   free_s(&FREED_got);
   ++g_testlib_failed;
-  if (testlib_showerror_isfatal) testlib_abort();
-  _spunlock(&testlib_showerror_lock);
+  if (testlib_showerror_isfatal) {
+    testlib_abort();
+  }
 }