initial import

grp/grpread.c

@@ -0,0 +1,135 @@
+/* Copyright (C) 1991, 1992 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <ansidecl.h>
+#include <errno.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <grp.h>
+
+/* This is the function that all the others are based on.
+   The format of the group file is known only here.  */
+
+/* Structure containing info kept by each __grpread caller.  */
+typedef struct
+  {
+    char *buf;
+    size_t buflen;
+    size_t max_members;
+    char **members;
+    struct group g;
+  } grpread_info;
+
+
+/* Return a chunk of memory containing a pre-initialized `grpread_info'.  */
+PTR
+DEFUN_VOID(__grpalloc)
+{
+  grpread_info *info = (PTR) malloc (sizeof(grpread_info));
+  if (info == NULL)
+    return NULL;
+
+  info->buf = NULL;
+  info->buflen = 0;
+
+  info->max_members = 5;
+  info->members = (char **) malloc (5 * sizeof(char *));
+  if (info->members == NULL)
+    {
+      free ((PTR) info);
+      return NULL;
+    }
+
+  return info;
+}
+
+/* Read a group entry from STREAM, filling in G.  */
+struct group *
+DEFUN(__grpread, (stream, g), FILE *stream AND PTR CONST g)
+{
+  register grpread_info *CONST info = (grpread_info *) g;
+  char *start, *end;
+  register size_t i;
+
+  /* Idiocy checks.  */
+  if (stream == NULL)
+    {
+      errno = EINVAL;
+      return NULL;
+    }
+
+  do
+    if (__getline (&info->buf, &info->buflen, stream) == -1)
+      return NULL;
+  while (info->buf[0] == '#');
+
+  start = info->buf;
+  end = strchr (start, ':');
+  if (end == NULL)
+    return NULL;
+  *end = '\0';
+  info->g.gr_name = start;
+
+  start = end + 1;
+  end = strchr (start, ':');
+  if (end == NULL)
+    return NULL;
+  *end = '\0';
+  info->g.gr_passwd = start;
+
+  info->g.gr_gid = (gid_t) strtol (end + 1, &end, 10);
+  if (*end != ':')
+    return NULL;
+
+  i = 0;
+  do
+    {
+      start = end + 1;
+      end = strchr (start, ',');
+      if (end == NULL)
+	{
+	  end = strchr (start, '\n');
+	  if (end == start)
+	    break;
+	  if (end == NULL)
+	    return NULL;
+	  *end = '\0';
+	  end = NULL;
+	}
+      else
+	*end = '\0';
+
+      if (i == info->max_members - 2)
+	{
+	  info->max_members += 5;
+	  info->members = (char **)
+	    realloc ((PTR) info->members, info->max_members * sizeof (char *));
+	  if (info->members == NULL)
+	    return NULL;
+	}
+
+      info->members[i++] = start;
+    } while (end != NULL);
+  info->members[i] = NULL;
+  info->g.gr_mem = info->members;
+
+  return &info->g;
+}