Polish recent changes and make improvements

- Simulate SIGPIPE on Windows NT
- Fix commandv() regression on Windows NT
- Fix sigprocmask() strace bug on OpenBSD
- Add many more system calls to --strace logging
- Make errno state more pristine in redbean strace

libc/rand/getrandom.c

@@ -19,6 +19,7 @@
 #include "libc/bits/bits.h"
 #include "libc/calls/calls.h"
 #include "libc/calls/internal.h"
+#include "libc/calls/strace.internal.h"
 #include "libc/dce.h"
 #include "libc/errno.h"
 #include "libc/nexgen32e/kcpuids.h"
@@ -67,18 +68,21 @@ ssize_t getrandom(void *p, size_t n, unsigned f) {
   char cf;
   ssize_t rc;
   uint64_t x;
-  size_t i, j, m;
   int fd, cmd[2];
+  size_t i, j, m;
+  const char *via;
   sigset_t neu, old;
   if (n > 256) n = 256;
   if ((f & ~(GRND_RANDOM | GRND_NONBLOCK))) return einval();
   if (IsWindows()) {
+    via = "RtlGenRandom";
     if (RtlGenRandom(p, n)) {
       rc = n;
     } else {
-      return __winerr();
+      rc = __winerr();
     }
   } else if (IsFreebsd() || IsNetbsd()) {
+    via = "KERN_ARND";
     if (IsFreebsd()) {
       cmd[0] = 1;  /* CTL_KERN */
       cmd[1] = 37; /* KERN_ARND */
@@ -91,27 +95,34 @@ ssize_t getrandom(void *p, size_t n, unsigned f) {
       rc = m;
     }
   } else if (have_getrandom) {
+    via = "getrandom";
     if ((rc = sys_getrandom(p, n, f & (GRND_RANDOM | GRND_NONBLOCK))) != -1) {
       if (!rc && (IsXnu() || IsOpenbsd())) {
         rc = n;
       }
     }
   } else if ((fd = __sys_openat(
-                  AT_FDCWD, (f & GRND_RANDOM) ? "/dev/random" : "/dev/urandom",
+                  AT_FDCWD,
+                  (via = (f & GRND_RANDOM) ? "/dev/random" : "/dev/urandom"),
                   O_RDONLY | ((f & GRND_NONBLOCK) ? O_NONBLOCK : 0), 0)) !=
              -1) {
     rc = sys_read(fd, p, n);
     sys_close(fd);
   } else {
-    return enosys();
+    rc = enosys();
   }
+  STRACE("getrandom(%p, %'zu, %#x) via %s → %'ld% m", p, n, f, via, rc);
   return rc;
 }
 
 static textstartup void getrandom_init(void) {
-  if (sys_getrandom(0, 0, 0) == 0) {
+  int e, rc;
+  e = errno;
+  if (!(rc = sys_getrandom(0, 0, 0))) {
     have_getrandom = true;
   }
+  STRACE("sys_getrandom(0,0,0) → %d% m");
+  errno = e;
 }
 
 const void *const g_getrandom_init[] initarray = {getrandom_init};