Merge from coreutils.

[gnulib.git] / lib / readutmp.c

diff --git a/lib/readutmp.c b/lib/readutmp.c
index e4caa82..71a913d 100644 (file)
--- a/lib/readutmp.c
+++ b/lib/readutmp.c
@@ -1,5 +1,5 @@
 /* GNU's read utmp module.
-   Copyright (C) 92, 93, 94, 95, 96, 1997 Free Software Foundation, Inc.
+   Copyright (C) 1992-2001, 2003 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
@@ -19,77 +19,121 @@
 
 #include <config.h>
 
+#include <stdio.h>
+
+#include <sys/types.h>
 #include <sys/stat.h>
-#if defined(STDC_HEADERS) || defined(HAVE_STRING_H)
-# include <string.h>
-#else
-# include <strings.h>
-#endif /* STDC_HEADERS || HAVE_STRING_H */
+#include <string.h>
+#include <stdlib.h>
 
 #include "readutmp.h"
-#include "error.h"
-
-char *xmalloc ();
-
-STRUCT_UTMP *utmp_contents = 0;
+#include "unlocked-io.h"
+#include "xalloc.h"
 
 /* Copy UT->ut_name into storage obtained from malloc.  Then remove any
    trailing spaces from the copy, NUL terminate it, and return the copy.  */
 
 char *
-extract_trimmed_name (ut)
-  const STRUCT_UTMP *ut;
+extract_trimmed_name (const STRUCT_UTMP *ut)
 {
   char *p, *trimmed_name;
 
-  trimmed_name = xmalloc (sizeof (ut->ut_name) + 1);
-  strncpy (trimmed_name, ut->ut_name, sizeof (ut->ut_name));
+  trimmed_name = xmalloc (sizeof (UT_USER (ut)) + 1);
+  strncpy (trimmed_name, UT_USER (ut), sizeof (UT_USER (ut)));
   /* Append a trailing space character.  Some systems pad names shorter than
      the maximum with spaces, others pad with NULs.  Remove any spaces.  */
-  trimmed_name[sizeof (ut->ut_name)] = ' ';
+  trimmed_name[sizeof (UT_USER (ut))] = ' ';
   p = strchr (trimmed_name, ' ');
   if (p != NULL)
     *p = '\0';
   return trimmed_name;
 }
 
-/* Read the utmp file FILENAME into UTMP_CONTENTS and return the
-   number of entries it contains. */
+/* Read the utmp entries corresponding to file FILENAME into freshly-
+   malloc'd storage, set *UTMP_BUF to that pointer, set *N_ENTRIES to
+   the number of entries, and return zero.  If there is any error,
+   return non-zero and don't modify the parameters.  */
+
+#ifdef UTMP_NAME_FUNCTION
+
+int
+read_utmp (const char *filename, int *n_entries, STRUCT_UTMP **utmp_buf)
+{
+  int n_read;
+  STRUCT_UTMP *u;
+  STRUCT_UTMP *utmp = NULL;
+
+  /* Ignore the return value for now.
+     Solaris' utmpname returns 1 upon success -- which is contrary
+     to what the GNU libc version does.  In addition, older GNU libc
+     versions are actually void.   */
+  UTMP_NAME_FUNCTION (filename);
+
+  SET_UTMP_ENT ();
+
+  n_read = 0;
+  while ((u = GET_UTMP_ENT ()) != NULL)
+    {
+      ++n_read;
+      utmp = (STRUCT_UTMP *) realloc (utmp, n_read * sizeof (STRUCT_UTMP));
+      if (utmp == NULL)
+       return 1;
+      utmp[n_read - 1] = *u;
+    }
+
+  END_UTMP_ENT ();
+
+  *n_entries = n_read;
+  *utmp_buf = utmp;
+
+  return 0;
+}
+
+#else
 
 int
-read_utmp (filename)
-  const char *filename;
+read_utmp (const char *filename, int *n_entries, STRUCT_UTMP **utmp_buf)
 {
   FILE *utmp;
   struct stat file_stats;
   size_t n_read;
   size_t size;
-
-  if (utmp_contents)
-    {
-      free (utmp_contents);
-      utmp_contents = 0;
-    }
+  STRUCT_UTMP *buf;
 
   utmp = fopen (filename, "r");
   if (utmp == NULL)
-    error (1, errno, "%s", filename);
+    return 1;
 
-  fstat (fileno (utmp), &file_stats);
+  if (fstat (fileno (utmp), &file_stats) != 0)
+    {
+      int e = errno;
+      fclose (utmp);
+      errno = e;
+      return 1;
+    }
   size = file_stats.st_size;
-  if (size > 0)
-    utmp_contents = (STRUCT_UTMP *) xmalloc (size);
-  else
+  buf = xmalloc (size);
+  n_read = fread (buf, sizeof *buf, size / sizeof *buf, utmp);
+  if (ferror (utmp))
     {
+      int e = errno;
+      free (buf);
       fclose (utmp);
-      return 0;
+      errno = e;
+      return 1;
+    }
+  if (fclose (utmp) != 0)
+    {
+      int e = errno;
+      free (buf);
+      errno = e;
+      return 1;
     }
 
-  /* Use < instead of != in case the utmp just grew.  */
-  n_read = fread (utmp_contents, 1, size, utmp);
-  if (ferror (utmp) || fclose (utmp) == EOF
-      || n_read < size)
-    error (1, errno, "%s", filename);
+  *n_entries = n_read;
+  *utmp_buf = buf;
 
-  return size / sizeof (STRUCT_UTMP);
+  return 0;
 }
+
+#endif