Add WSL to test fleet

All tests pass now under WSL2. They should pass under WSL1 too, but only
WSL2 is integrated into the test fleet right now. This change also fills
in some gaps in the error numbers.

Fixes #665

libc/calls/__sig2.c

@@ -108,7 +108,6 @@ static bool __sig_deliver(bool restartable, int sig, int si_code,
   STRACE("delivering %G", sig);
 
   // enter the signal
-  __sig_lock();
   rva = __sighandrvas[sig];
   flags = __sighandflags[sig];
   if ((~flags & SA_NODEFER) || (flags & SA_RESETHAND)) {
@@ -119,7 +118,6 @@ static bool __sig_deliver(bool restartable, int sig, int si_code,
     // signal handler. in that case you must use SA_NODEFER.
     __sighandrvas[sig] = (int32_t)(intptr_t)SIG_DFL;
   }
-  __sig_unlock();
 
   // setup the somewhat expensive information args
   // only if they're requested by the user in sigaction()
@@ -141,11 +139,9 @@ static bool __sig_deliver(bool restartable, int sig, int si_code,
     // since sigaction() is @asyncsignalsafe we only restore it if the
     // user didn't change it during the signal handler. we also don't
     // need to do anything if this was a oneshot signal or nodefer.
-    __sig_lock();
     if (__sighandrvas[sig] == (int32_t)(intptr_t)SIG_DFL) {
       __sighandrvas[sig] = rva;
     }
-    __sig_unlock();
   }
 
   if (!restartable) {
@@ -228,12 +224,12 @@ textwindows int __sig_add(int tid, int sig, int si_code) {
   int rc;
   struct Signal *mem;
   if (1 <= sig && sig <= 64) {
-    __sig_lock();
     if (__sighandrvas[sig] == (unsigned)(intptr_t)SIG_IGN) {
       STRACE("ignoring %G", sig);
       rc = 0;
     } else {
       STRACE("enqueuing %G", sig);
+      __sig_lock();
       ++__sig_count;
       if ((mem = __sig_alloc())) {
         mem->tid = tid;
@@ -245,8 +241,8 @@ textwindows int __sig_add(int tid, int sig, int si_code) {
       } else {
         rc = enomem();
       }
+      __sig_unlock();
     }
-    __sig_unlock();
   } else {
     rc = einval();
   }

libc/calls/sigaction.c

@@ -85,9 +85,11 @@ union metasigaction {
   struct sigaction_xnu_out xnu_out;
 };
 
-void __sigenter_netbsd(int, void *, void *) hidden;
-void __sigenter_freebsd(int, void *, void *) hidden;
-void __sigenter_openbsd(int, void *, void *) hidden;
+void __sigenter_xnu(int, struct siginfo *, void *) hidden;
+void __sigenter_linux(int, struct siginfo *, void *) hidden;
+void __sigenter_netbsd(int, struct siginfo *, void *) hidden;
+void __sigenter_freebsd(int, struct siginfo *, void *) hidden;
+void __sigenter_openbsd(int, struct siginfo *, void *) hidden;
 
 static void sigaction_cosmo2native(union metasigaction *sa) {
   if (!sa) return;
@@ -156,6 +158,7 @@ static int __sigaction(int sig, const struct sigaction *act,
                  "sigaction cosmo abi needs tuning");
   int64_t arg4, arg5;
   int rc, rva, oldrva;
+  sigaction_f sigenter;
   struct sigaction *ap, copy;
   if (IsMetal()) return enosys(); /* TODO: Signals on Metal */
   if (!(0 < sig && sig < NSIG)) return einval();
@@ -183,11 +186,7 @@ static int __sigaction(int sig, const struct sigaction *act,
       ap = &copy;
       if (IsXnu()) {
         ap->sa_restorer = (void *)&__sigenter_xnu;
-        if (rva < kSigactionMinRva) {
-          ap->sa_sigaction = (void *)(intptr_t)rva;
-        } else {
-          ap->sa_sigaction = (void *)&__sigenter_xnu;
-        }
+        sigenter = __sigenter_xnu;
         // mitigate Rosetta signal handling strangeness
         // https://github.com/jart/cosmopolitan/issues/455
         ap->sa_flags |= SA_SIGINFO;
@@ -196,27 +195,21 @@ static int __sigaction(int sig, const struct sigaction *act,
           ap->sa_flags |= SA_RESTORER;
           ap->sa_restorer = &__restore_rt;
         }
+        sigenter = __sigenter_linux;
       } else if (IsNetbsd()) {
-        if (rva < kSigactionMinRva) {
-          ap->sa_sigaction = (void *)(intptr_t)rva;
-        } else {
-          ap->sa_sigaction = (sigaction_f)__sigenter_netbsd;
-        }
+        sigenter = __sigenter_netbsd;
       } else if (IsFreebsd()) {
-        if (rva < kSigactionMinRva) {
-          ap->sa_sigaction = (void *)(intptr_t)rva;
-        } else {
-          ap->sa_sigaction = (sigaction_f)__sigenter_freebsd;
-        }
+        sigenter = __sigenter_freebsd;
       } else if (IsOpenbsd()) {
-        if (rva < kSigactionMinRva) {
-          ap->sa_sigaction = (void *)(intptr_t)rva;
-        } else {
-          ap->sa_sigaction = (sigaction_f)__sigenter_openbsd;
-        }
+        sigenter = __sigenter_openbsd;
       } else {
         return enosys();
       }
+      if (rva < kSigactionMinRva) {
+        ap->sa_sigaction = (void *)(intptr_t)rva;
+      } else {
+        ap->sa_sigaction = sigenter;
+      }
       sigaction_cosmo2native((union metasigaction *)ap);
     } else {
       ap = NULL;
@@ -468,7 +461,6 @@ static int __sigaction(int sig, const struct sigaction *act,
  * @return 0 on success or -1 w/ errno
  * @see xsigaction() for a much better api
  * @asyncsignalsafe
- * @threadsafe
  * @vforksafe
  */
 int sigaction(int sig, const struct sigaction *act, struct sigaction *oldact) {
@@ -476,11 +468,7 @@ 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/sigchld-nt.c

@@ -49,16 +49,16 @@ void _check_sigchld(void) {
   i = WaitForMultipleObjects(n, handles, false, 0);
   if (i == kNtWaitTimeout) return;
   if (i == kNtWaitFailed) {
-    STRACE("%s failed %u", "WaitForMultipleObjects", GetLastError());
+    NTTRACE("%s failed %u", "WaitForMultipleObjects", GetLastError());
     return;
   }
   if (__sighandrvas[SIGCHLD] == (intptr_t)SIG_IGN ||
       __sighandrvas[SIGCHLD] == (intptr_t)SIG_DFL) {
-    STRACE("new zombie fd=%d handle=%ld", pids[i], handles[i]);
+    NTTRACE("new zombie fd=%d handle=%ld", pids[i], handles[i]);
     return;
   }
   if (__sighandflags[SIGCHLD] & SA_NOCLDWAIT) {
-    STRACE("SIGCHILD SA_NOCLDWAIT fd=%d handle=%ld", pids[i], handles[i]);
+    NTTRACE("SIGCHILD SA_NOCLDWAIT fd=%d handle=%ld", pids[i], handles[i]);
     CloseHandle(handles[i]);
     __releasefd(pids[i]);
   }

libc/calls/sigenter-linux.c

@@ -0,0 +1,48 @@
+/*-*- 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 "ape/sections.internal.h"
+#include "libc/calls/calls.h"
+#include "libc/calls/internal.h"
+#include "libc/calls/state.internal.h"
+#include "libc/calls/struct/sigaction.h"
+#include "libc/calls/struct/siginfo.h"
+#include "libc/calls/ucontext.h"
+#include "libc/intrin/likely.h"
+#include "libc/math.h"
+#include "libc/str/str.h"
+#include "libc/sysv/consts/sa.h"
+
+privileged void __sigenter_linux(int sig, struct siginfo *info,
+                                 ucontext_t *ctx) {
+  int i, rva, flags;
+  rva = __sighandrvas[sig & (NSIG - 1)];
+  if (rva >= kSigactionMinRva) {
+    flags = __sighandflags[sig & (NSIG - 1)];
+    // WSL1 doesn't set the fpregs field.
+    // https://github.com/microsoft/WSL/issues/2555
+    if ((flags & SA_SIGINFO) && UNLIKELY(!ctx->uc_mcontext.fpregs)) {
+      ctx->uc_mcontext.fpregs = &ctx->__fpustate;
+      for (i = 0; i < 8; ++i) {
+        long double nan = NAN;
+        memcpy(ctx->__fpustate.st + i, &nan, 16);
+      }
+    }
+    ((sigaction_f)(_base + rva))(sig, info, ctx);
+  }
+}

libc/calls/struct/siginfo.internal.h

@@ -8,8 +8,6 @@
 COSMOPOLITAN_C_START_
 
 int sys_sigqueueinfo(int, const siginfo_t *) hidden;
-void __sigenter_xnu(void *, int, int, struct siginfo_xnu *,
-                    struct __darwin_ucontext *) hidden;
 
 const char *DescribeSiginfo(char[300], int, const siginfo_t *);
 #define DescribeSiginfo(x, y) DescribeSiginfo(alloca(300), x, y)