isatty: Fix test failure of ptsname_r on native Windows.

[gnulib.git] / lib / sigaction.c

diff --git a/lib/sigaction.c b/lib/sigaction.c
index 9b0c92f..659c4ec 100644 (file)
--- a/lib/sigaction.c
+++ b/lib/sigaction.c
@@ -1,5 +1,5 @@
 /* POSIX compatible signal blocking.
 /* POSIX compatible signal blocking.

-   Copyright (C) 2008 Free Software Foundation, Inc.
+   Copyright (C) 2008-2012 Free Software Foundation, Inc.

    Written by Eric Blake <ebb9@byu.net>, 2008.
 
    This program is free software: you can redistribute it and/or modify
    Written by Eric Blake <ebb9@byu.net>, 2008.
 
    This program is free software: you can redistribute it and/or modify


@@ -24,7 +24,7 @@
 #include <stdint.h>
 #include <stdlib.h>
 
 #include <stdint.h>
 #include <stdlib.h>
 

-/* This implementation of sigaction is tailored to Woe32 behavior:
+/* This implementation of sigaction is tailored to native Windows behavior:

    signal() has SysV semantics (ie. the handler is uninstalled before
    it is invoked).  This is an inherent data race if an asynchronous
    signal is sent twice in a row before we can reinstall our handler,
    signal() has SysV semantics (ie. the handler is uninstalled before
    it is invoked).  This is an inherent data race if an asynchronous
    signal is sent twice in a row before we can reinstall our handler,


@@ -35,11 +35,15 @@
    the situation by reading static storage in a signal handler, which
    POSIX warns is not generically async-signal-safe.  Oh well.
 
    the situation by reading static storage in a signal handler, which
    POSIX warns is not generically async-signal-safe.  Oh well.
 

-   Additionally, SIGCHLD is not defined, so we don't implement
-   SA_NOCLDSTOP or SA_NOCLDWAIT; sigaltstack() is not present, so we
-   don't implement SA_ONSTACK; and siginterrupt() is not present, so
-   we don't implement SA_RESTART.  Supporting SA_SIGINFO is impossible
-   to do portably.
+   Additionally:
+     - We don't implement SA_NOCLDSTOP or SA_NOCLDWAIT, because SIGCHLD
+       is not defined.
+     - We don't implement SA_ONSTACK, because sigaltstack() is not present.
+     - We ignore SA_RESTART, because blocking native Windows API calls are
+       not interrupted anyway when an asynchronous signal occurs, and the
+       MSVCRT runtime never sets errno to EINTR.
+     - We don't implement SA_SIGINFO because it is impossible to do so
+       portably.

 
    POSIX states that an application should not mix signal() and
    sigaction().  We support the use of signal() within the gnulib
 
    POSIX states that an application should not mix signal() and
    sigaction().  We support the use of signal() within the gnulib


@@ -60,6 +64,14 @@
 # define SIGSTOP (-1)
 #endif
 
 # define SIGSTOP (-1)
 #endif
 

+/* On native Windows, as of 2008, the signal SIGABRT_COMPAT is an alias
+   for the signal SIGABRT.  Only one signal handler is stored for both
+   SIGABRT and SIGABRT_COMPAT.  SIGABRT_COMPAT is not a signal of its own.  */
+#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+# undef SIGABRT_COMPAT
+# define SIGABRT_COMPAT 6
+#endif
+

 /* A signal handler.  */
 typedef void (*handler_t) (int signal);
 
 /* A signal handler.  */
 typedef void (*handler_t) (int signal);
 


@@ -79,7 +91,7 @@ sigaction_handler (int sig)
     {
       /* Unexpected situation; be careful to avoid recursive abort.  */
       if (sig == SIGABRT)
     {
       /* Unexpected situation; be careful to avoid recursive abort.  */
       if (sig == SIGABRT)

-       signal (SIGABRT, SIG_DFL);
+        signal (SIGABRT, SIG_DFL);

       abort ();
     }
 
       abort ();
     }
 


@@ -130,6 +142,11 @@ sigaction (int sig, const struct sigaction *restrict act,
       return -1;
     }
 
       return -1;
     }
 

+#ifdef SIGABRT_COMPAT
+  if (sig == SIGABRT_COMPAT)
+    sig = SIGABRT;
+#endif
+

   /* POSIX requires sigaction() to be async-signal-safe.  In other
      words, if an asynchronous signal can occur while we are anywhere
      inside this function, the user's handler could then call
   /* POSIX requires sigaction() to be async-signal-safe.  In other
      words, if an asynchronous signal can occur while we are anywhere
      inside this function, the user's handler could then call