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-rw-r--r--libpwdgrp/__getpwent.c115
1 files changed, 115 insertions, 0 deletions
diff --git a/libpwdgrp/__getpwent.c b/libpwdgrp/__getpwent.c
new file mode 100644
index 000000000..e406b8824
--- /dev/null
+++ b/libpwdgrp/__getpwent.c
@@ -0,0 +1,115 @@
+/*
+ * __getpwent.c - This file is part of the libc-8086/pwd package for ELKS,
+ * Copyright (C) 1995, 1996 Nat Friedman <ndf@linux.mit.edu>.
+ *
+ * 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 "busybox.h"
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <fcntl.h>
+#include "pwd.h"
+
+#define PWD_BUFFER_SIZE 256
+
+/* This isn't as flash as my previous version -- it doesn't dynamically
+ scale down the gecos on too-long lines, but it also makes fewer syscalls,
+ so it's probably nicer. Write me if you want the old version. Maybe I
+ should include it as a build-time option... ?
+ -Nat <ndf@linux.mit.edu> */
+
+struct passwd *__getpwent(int pwd_fd)
+{
+ static char line_buff[PWD_BUFFER_SIZE];
+ static struct passwd passwd;
+ char *field_begin;
+ char *endptr;
+ char *gid_ptr=NULL;
+ char *uid_ptr=NULL;
+ int line_len;
+ int i;
+
+ /* We use the restart label to handle malformatted lines */
+ restart:
+ /* Read the passwd line into the static buffer using a minimal of
+ syscalls. */
+ if ((line_len = read(pwd_fd, line_buff, PWD_BUFFER_SIZE)) <= 0)
+ return NULL;
+ field_begin = strchr(line_buff, '\n');
+ if (field_begin != NULL)
+ lseek(pwd_fd, (long) (1 + field_begin - (line_buff + line_len)),
+ SEEK_CUR);
+ else { /* The line is too long - skip it. :-\ */
+
+ do {
+ if ((line_len = read(pwd_fd, line_buff, PWD_BUFFER_SIZE)) <= 0)
+ return NULL;
+ } while (!(field_begin = strchr(line_buff, '\n')));
+ lseek(pwd_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 < 7; i++) {
+ switch (i) {
+ case 0:
+ passwd.pw_name = field_begin;
+ break;
+ case 1:
+ passwd.pw_passwd = field_begin;
+ break;
+ case 2:
+ uid_ptr = field_begin;
+ break;
+ case 3:
+ gid_ptr = field_begin;
+ break;
+ case 4:
+ passwd.pw_gecos = field_begin;
+ break;
+ case 5:
+ passwd.pw_dir = field_begin;
+ break;
+ case 6:
+ passwd.pw_shell = field_begin;
+ break;
+ }
+ if (i < 6) {
+ field_begin = strchr(field_begin, ':');
+ if (field_begin == NULL)
+ goto restart;
+ *field_begin++ = '\0';
+ }
+ }
+ passwd.pw_gid = (gid_t) strtoul(gid_ptr, &endptr, 10);
+ if (*endptr != '\0')
+ goto restart;
+
+ passwd.pw_uid = (uid_t) strtoul(uid_ptr, &endptr, 10);
+ if (*endptr != '\0')
+ goto restart;
+
+ return &passwd;
+}