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authorEric Andersen <andersen@codepoet.org>2003-10-10 07:34:27 +0000
committerEric Andersen <andersen@codepoet.org>2003-10-10 07:34:27 +0000
commit56104838733c81ba410ac41f767ac72267049489 (patch)
tree54057d78cdae893235b86787a735629396d857a5 /libc/pwd_grp/__getgrent_r.c
parent61011662018fa98c4610c1ae826e417678cd5c80 (diff)
Implement getgrgid_r and getgrnam_r. Rework group handling code to be fully
reentrant, since there was still a shared static value. indent stuff,
Diffstat (limited to 'libc/pwd_grp/__getgrent_r.c')
-rw-r--r--libc/pwd_grp/__getgrent_r.c114
1 files changed, 114 insertions, 0 deletions
diff --git a/libc/pwd_grp/__getgrent_r.c b/libc/pwd_grp/__getgrent_r.c
new file mode 100644
index 000000000..69559bdb1
--- /dev/null
+++ b/libc/pwd_grp/__getgrent_r.c
@@ -0,0 +1,114 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * __getgrent.c - This file is part of the libc-8086/grp package for ELKS,
+ * Copyright (C) 1995, 1996 Nat Friedman <ndf@linux.mit.edu>.
+ * Copyright (C) 2001-2003 Erik Andersen <andersee@debian.org>
+ *
+ * This 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.
+ *
+ * This 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 this library; if not, write to the Free
+ * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include <features.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include "config.h"
+
+
+/*
+ * This is the core group-file read function. It behaves exactly like
+ * getgrent() except that it is passed a file descriptor. getgrent()
+ * is just a wrapper for this function.
+ */
+int __getgrent_r (struct group *__restrict group,
+ char *__restrict line_buff, size_t buflen, int grp_fd)
+{
+ char *endptr, *field_begin, **members;
+ int i, line_len, member_num = 0;
+
+
+ if (buflen<GRP_BUFFER_SIZE) {
+ return ERANGE;
+ }
+
+ /* We use the restart label to handle malformatted lines */
+restart:
+ /* Read the group line into the buffer for processing */
+ if ((line_len = read(grp_fd, line_buff, buflen)) <= 0) {
+ return EIO;
+ }
+ field_begin = strchr(line_buff, '\n');
+ if (field_begin != NULL)
+ lseek(grp_fd, (long) (1 + field_begin - (line_buff + line_len)), SEEK_CUR);
+ else {
+ /* The line is too long - skip it. :-\ */
+ do {
+ if ((line_len = read(grp_fd, line_buff, buflen)) <= 0) {
+ return EIO;
+ }
+ } while (!(field_begin = strchr(line_buff, '\n')));
+ lseek(grp_fd, (long) (field_begin - line_buff) - line_len + 1, SEEK_CUR);
+ goto restart;
+ }
+ if (*line_buff == '#' || *line_buff == ' ' || *line_buff == '\n' || *line_buff == '\t')
+ goto restart;
+ *field_begin = '\0';
+
+ /* We've read the line; now parse it. */
+ field_begin = line_buff;
+ for (i = 0; i < 3; i++) {
+ switch (i) {
+ case 0:
+ group->gr_name = field_begin;
+ break;
+ case 1:
+ group->gr_passwd = field_begin;
+ break;
+ case 2:
+ group->gr_gid = (__gid_t) strtoul(field_begin, &endptr, 10);
+ if (*endptr != ':')
+ goto restart;
+ break;
+ }
+ if (i < 3) {
+ field_begin = strchr(field_begin, ':');
+ if (field_begin == NULL)
+ break;
+ *field_begin++ = '\0';
+ }
+ }
+
+ members = (char **) malloc(sizeof(char *));
+ if (members==NULL) {
+ return ENOMEM;
+ }
+ while(field_begin && strlen(field_begin)) {
+ members[member_num++] = field_begin;
+ members = (char **) realloc(members, (member_num + 1) * sizeof(char *));
+ if (members==NULL) {
+ return ENOMEM;
+ }
+ endptr = strchr(field_begin, ',');
+ if (endptr == NULL) {
+ /* Final entry */
+ break;
+ }
+ *field_begin++ = '\0';
+ }
+ members[member_num] = NULL;
+ group->gr_mem = members;
+ return 0;
+}