gettimeofday: port recent C++ fix to Emacs

[gnulib.git] / lib / strerror_r.c

diff --git a/lib/strerror_r.c b/lib/strerror_r.c
index 93e33fa..e86d272 100644 (file)
--- a/lib/strerror_r.c
+++ b/lib/strerror_r.c
@@ -1,6 +1,6 @@
 /* strerror_r.c --- POSIX compatible system error routine
 
-   Copyright (C) 2010-2011 Free Software Foundation, Inc.
+   Copyright (C) 2010-2013 Free Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -34,6 +34,7 @@
 #if (__GLIBC__ >= 2 || defined __UCLIBC__ || defined __CYGWIN__) && HAVE___XPG_STRERROR_R /* glibc >= 2.3.4, cygwin >= 1.7.9 */
 
 # define USE_XPG_STRERROR_R 1
+extern int __xpg_strerror_r (int errnum, char *buf, size_t buflen);
 
 #elif HAVE_DECL_STRERROR_R && !(__GLIBC__ >= 2 || defined __UCLIBC__ || defined __CYGWIN__)
 
@@ -86,6 +87,27 @@ gl_lock_define_initialized(static, strerror_lock)
 
 #endif
 
+/* On MSVC, there is no snprintf() function, just a _snprintf().
+   It is of lower quality, but sufficient for the simple use here.
+   We only have to make sure to NUL terminate the result (_snprintf
+   does not NUL terminate, like strncpy).  */
+#if !HAVE_SNPRINTF
+static int
+local_snprintf (char *buf, size_t buflen, const char *format, ...)
+{
+  va_list args;
+  int result;
+
+  va_start (args, format);
+  result = _vsnprintf (buf, buflen, format, args);
+  va_end (args);
+  if (buflen > 0 && (result < 0 || result >= buflen))
+    buf[buflen - 1] = '\0';
+  return result;
+}
+# define snprintf local_snprintf
+#endif
+
 /* Copy as much of MSG into BUF as possible, without corrupting errno.
    Return 0 if MSG fit in BUFLEN, otherwise return ERANGE.  */
 static int
@@ -140,8 +162,6 @@ strerror_r (int errnum, char *buf, size_t buflen)
 #if USE_XPG_STRERROR_R
 
     {
-      extern int __xpg_strerror_r (int errnum, char *buf, size_t buflen);
-
       ret = __xpg_strerror_r (errnum, buf, buflen);
       if (ret < 0)
         ret = errno;
@@ -175,18 +195,11 @@ strerror_r (int errnum, char *buf, size_t buflen)
         ret = strerror_r (errnum, buf, buflen);
     }
 # else
-    /* Solaris 10 does not populate buf on ERANGE.  */
     ret = strerror_r (errnum, buf, buflen);
-    if (ret == ERANGE && !*buf)
-      {
-        char stackbuf[STACKBUF_LEN];
 
-        /* strerror-impl.h is also affected if our choice of stackbuf
-           size is not large enough.  */
-        if (strerror_r (errnum, stackbuf, sizeof stackbuf) == ERANGE)
-          abort ();
-        safe_copy (buf, buflen, stackbuf);
-      }
+    /* Some old implementations may return (-1, EINVAL) instead of EINVAL.  */
+    if (ret < 0)
+      ret = errno;
 # endif
 
 # ifdef _AIX
@@ -198,34 +211,42 @@ strerror_r (int errnum, char *buf, size_t buflen)
         size_t len;
         strerror_r (errnum, stackbuf, sizeof stackbuf);
         len = strlen (stackbuf);
-        /* stackbuf should have been large enough.  */
+        /* STACKBUF_LEN should have been large enough.  */
         if (len + 1 == sizeof stackbuf)
           abort ();
         if (buflen <= len)
           ret = ERANGE;
       }
-# endif
-
-    /* Some old implementations may return (-1, EINVAL) instead of EINVAL.  */
-    if (ret < 0)
-      ret = errno;
+# else
+    /* Solaris 10 does not populate buf on ERANGE.  OpenBSD 4.7
+       truncates early on ERANGE rather than return a partial integer.
+       We prefer the maximal string.  We set buf[0] earlier, and we
+       know of no implementation that modifies buf to be an
+       unterminated string, so this strlen should be portable in
+       practice (rather than pulling in a safer strnlen).  */
+    if (ret == ERANGE && strlen (buf) < buflen - 1)
+      {
+        char stackbuf[STACKBUF_LEN];
 
-    /* FreeBSD rejects 0; see http://austingroupbugs.net/view.php?id=382.  */
-    if (errnum == 0 && ret == EINVAL)
-      ret = safe_copy (buf, buflen, "Success");
+        /* STACKBUF_LEN should have been large enough.  */
+        if (strerror_r (errnum, stackbuf, sizeof stackbuf) == ERANGE)
+          abort ();
+        safe_copy (buf, buflen, stackbuf);
+      }
+# endif
 
 #else /* USE_SYSTEM_STRERROR */
 
     /* Try to do what strerror (errnum) does, but without clobbering the
        buffer used by strerror().  */
 
-# if defined __NetBSD__ || defined __hpux || ((defined _WIN32 || defined __WIN32__) && !defined __CYGWIN__) || defined __CYGWIN__ /* NetBSD, HP-UX, native Win32, Cygwin */
+# if defined __NetBSD__ || defined __hpux || ((defined _WIN32 || defined __WIN32__) && !defined __CYGWIN__) || defined __CYGWIN__ /* NetBSD, HP-UX, native Windows, Cygwin */
 
-    /* NetBSD:        sys_nerr, sys_errlist are declared through _NETBSD_SOURCE
-                      and <errno.h> above.
-       HP-UX:         sys_nerr, sys_errlist are declared explicitly above.
-       native Win32:  sys_nerr, sys_errlist are declared in <stdlib.h>.
-       Cygwin:        sys_nerr, sys_errlist are declared in <errno.h>.  */
+    /* NetBSD:         sys_nerr, sys_errlist are declared through _NETBSD_SOURCE
+                       and <errno.h> above.
+       HP-UX:          sys_nerr, sys_errlist are declared explicitly above.
+       native Windows: sys_nerr, sys_errlist are declared in <stdlib.h>.
+       Cygwin:         sys_nerr, sys_errlist are declared in <errno.h>.  */
     if (errnum >= 0 && errnum < sys_nerr)
       {
 #  if HAVE_CATGETS && (defined __NetBSD__ || defined __hpux)