PR 47375 getlog thread safety

From-SVN: r169243

libgfortran/ChangeLog

+2011-01-25  Janne Blomqvist  <jb@gcc.gnu.org>
+
+	PR libfortran/47375
+	* config.h.in: Regenerated.
+	* configure: Regenerated.
+	* configure.ac: Add check for getpwuid_r.
+	* intrinsics/getlog.c (getlog): Use getpwuid_r() if available.
+
 2011-01-22  Janne Blomqvist  <jb@gcc.gnu.org>
 
 	PR libfortran/46267

libgfortran/config.h.in

@@ -462,6 +462,9 @@
 /* Define to 1 if you have the `getpwuid' function. */
 #undef HAVE_GETPWUID
 
+/* Define to 1 if you have the `getpwuid_r' function. */
+#undef HAVE_GETPWUID_R
+
 /* Define to 1 if you have the `getrlimit' function. */
 #undef HAVE_GETRLIMIT
 

libgfortran/configure

@@ -15636,7 +15636,7 @@ _ACEOF
 fi
 done
 
-for ac_func in localtime_r gmtime_r strerror_r
+for ac_func in localtime_r gmtime_r strerror_r getpwuid_r
 do :
   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
 ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"

libgfortran/configure.ac

@@ -249,7 +249,7 @@ AC_CHECK_FUNCS(chdir strerror getlogin gethostname kill link symlink perror)
 AC_CHECK_FUNCS(sleep time ttyname signal alarm ctime clock access fork execl)
 AC_CHECK_FUNCS(wait setmode execvp pipe dup2 close fdopen strcasestr getrlimit)
 AC_CHECK_FUNCS(gettimeofday stat fstat lstat getpwuid vsnprintf dup getcwd)
-AC_CHECK_FUNCS(localtime_r gmtime_r strerror_r)
+AC_CHECK_FUNCS(localtime_r gmtime_r strerror_r getpwuid_r)
 
 # Check for glibc backtrace functions
 AC_CHECK_FUNCS(backtrace backtrace_symbols)

libgfortran/intrinsics/getlog.c

 /* Implementation of the GETLOG g77 intrinsic.
-   Copyright (C) 2005, 2007, 2009 Free Software Foundation, Inc.
+   Copyright (C) 2005, 2007, 2009, 2011 Free Software Foundation, Inc.
    Contributed by François-Xavier Coudert <coudert@clipper.ens.fr>
 
-This file is part of the GNU Fortran 95 runtime library (libgfortran).
+This file is part of the GNU Fortran runtime library (libgfortran).
 
 Libgfortran is free software; you can redistribute it and/or
 modify it under the terms of the GNU General Public
@@ -75,7 +75,22 @@ PREFIX(getlog) (char * login, gfc_charlen_type login_len)
 
   memset (login, ' ', login_len); /* Blank the string.  */
 
-#if defined(HAVE_GETPWUID) && defined(HAVE_GETEUID)
+#if defined(HAVE_GETPWUID_R) && defined(HAVE_GETEUID)
+  struct passwd pwd;
+  struct passwd *result;
+  char *buf;
+  int err;
+  /* To be pedantic, buflen should be determined by
+     sysconf(_SC_GETPW_R_SIZE_MAX), which is 1024 on some tested
+     targets; we do something simple in case the target doesn't
+     support sysconf.  */
+  static const size_t buflen = 1024;
+  buf = get_mem (buflen);
+  err = getpwuid_r (geteuid (), &pwd, buf, buflen, &result);
+  if (err != 0 || result == NULL)
+    goto cleanup;
+  p = pwd.pw_name;
+#elif defined(HAVE_GETPWUID) && defined(HAVE_GETEUID)
   {
     struct passwd *pw = getpwuid (geteuid ());
     if (pw)
@@ -83,20 +98,22 @@ PREFIX(getlog) (char * login, gfc_charlen_type login_len)
     else
       return;
   }
-#else
-# ifdef HAVE_GETLOGIN
+#elif HAVE_GETLOGIN
   p = getlogin();
 # else
   return;
-# endif
 #endif
 
   if (p == NULL)
-    return;
+    goto cleanup;
 
   p_len = strlen (p);
   if (login_len < p_len)
-    memcpy (login, p, login_len);
-  else
-    memcpy (login, p, p_len);
+    p_len = login_len;
+  memcpy (login, p, p_len);
+
+ cleanup:
+#ifdef HAVE_GETPWUID_R
+  free (buf);
+#endif
 }