X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fgetgroups.c;h=62234d9754ed6a826b1228b1750f97b7589e2365;hb=b0f648cf3ba46b06c44bf84ec74480a42f8666ba;hp=207a44189843e40f1b7c809157216e1af96dfd97;hpb=08e6b4c6ba690adba619a3c1695bc312d3e98136;p=gnulib.git

diff --git a/lib/getgroups.c b/lib/getgroups.c
index 207a44189..62234d975 100644
--- a/lib/getgroups.c
+++ b/lib/getgroups.c
@@ -1,7 +1,6 @@
 /* provide consistent interface to getgroups for systems that don't allow N==0
 
-   Copyright (C) 1996, 1999, 2003, 2006, 2007, 2008, 2009 Free
-   Software Foundation, Inc.
+   Copyright (C) 1996, 1999, 2003, 2006-2013 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
@@ -20,30 +19,91 @@
 
 #include <config.h>
 
-#undef getgroups
+#include <unistd.h>
 
-#include <stdio.h>
-#include <sys/types.h>
 #include <errno.h>
 #include <stdlib.h>
-#include <unistd.h>
+#include <stdint.h>
+
+#if !HAVE_GETGROUPS
+
+/* Provide a stub that fails with ENOSYS, since there is no group
+   information available on mingw.  */
+int
+getgroups (int n _GL_UNUSED, GETGROUPS_T *groups _GL_UNUSED)
+{
+  errno = ENOSYS;
+  return -1;
+}
+
+#else /* HAVE_GETGROUPS */
+
+# undef getgroups
+# ifndef GETGROUPS_ZERO_BUG
+#  define GETGROUPS_ZERO_BUG 0
+# endif
 
-#include "xalloc.h"
+/* On OS X 10.6 and later, use the usual getgroups, not the one
+   supplied when _DARWIN_C_SOURCE is defined.  _DARWIN_C_SOURCE is
+   normally defined, since it means "conform to POSIX, but add
+   non-POSIX extensions even if that violates the POSIX namespace
+   rules", which is what we normally want.  But with getgroups there
+   is an inconsistency, and _DARWIN_C_SOURCE means "change getgroups()
+   so that it no longer works right".  The BUGS section of compat(5)
+   says that the behavior is dubious if you compile different sections
+   of a program with different _DARWIN_C_SOURCE settings, so fix only
+   the offending symbol.  */
+#ifdef __APPLE__
+int posix_getgroups (int, gid_t []) __asm ("_getgroups");
+# define getgroups posix_getgroups
+#endif
 
-/* On at least Ultrix 4.3 and NextStep 3.2, getgroups (0, 0) always fails.
-   On other systems, it returns the number of supplemental groups for the
-   process.  This function handles that special case and lets the system-
-   provided function handle all others. */
+/* On at least Ultrix 4.3 and NextStep 3.2, getgroups (0, NULL) always
+   fails.  On other systems, it returns the number of supplemental
+   groups for the process.  This function handles that special case
+   and lets the system-provided function handle all others.  However,
+   it can fail with ENOMEM if memory is tight.  It is unspecified
+   whether the effective group id is included in the list.  */
 
 int
-rpl_getgroups (int n, GETGROUPS_T *group)
+rpl_getgroups (int n, gid_t *group)
 {
   int n_groups;
   GETGROUPS_T *gbuf;
   int saved_errno;
 
-  if (n != 0)
-    return getgroups (n, group);
+  if (n < 0)
+    {
+      errno = EINVAL;
+      return -1;
+    }
+
+  if (n != 0 || !GETGROUPS_ZERO_BUG)
+    {
+      int result;
+      if (sizeof *group == sizeof *gbuf)
+        return getgroups (n, (GETGROUPS_T *) group);
+
+      if (SIZE_MAX / sizeof *gbuf <= n)
+        {
+          errno = ENOMEM;
+          return -1;
+        }
+      gbuf = malloc (n * sizeof *gbuf);
+      if (!gbuf)
+        return -1;
+      result = getgroups (n, gbuf);
+      if (0 <= result)
+        {
+          n = result;
+          while (n--)
+            group[n] = gbuf[n];
+        }
+      saved_errno = errno;
+      free (gbuf);
+      errno = saved_errno;
+      return result;
+    }
 
   n = 20;
   while (1)
@@ -51,7 +111,9 @@ rpl_getgroups (int n, GETGROUPS_T *group)
       /* No need to worry about address arithmetic overflow here,
          since the ancient systems that we're running on have low
          limits on the number of secondary groups.  */
-      gbuf = xmalloc (n * sizeof *gbuf);
+      gbuf = malloc (n * sizeof *gbuf);
+      if (!gbuf)
+        return -1;
       n_groups = getgroups (n, gbuf);
       if (n_groups == -1 ? errno != EINVAL : n_groups < n)
         break;
@@ -65,3 +127,5 @@ rpl_getgroups (int n, GETGROUPS_T *group)
 
   return n_groups;
 }
+
+#endif /* HAVE_GETGROUPS */