Bigger patch for (partial) tinylogin integration

- Made a new dir loginutils
- Moved all applets from pwd_grp to loginutils
- Added new applets su.c login.c to loginutils
- Made a new dir libpwdgrp
- Moved everything from pwd_grp/libpwd_grp there
- Added shadow.c to libpwdgrp
- Removed dir pwd_grp
- Added usage strings for login and su to usage.h
- Changed main Makefile to reflect the dir rearrangements
[Parts of this patch may overlap with my other two patches]

1 files changed, 115 insertions, 0 deletions

diff --git a/libpwdgrp/__getpwent.c b/libpwdgrp/__getpwent.c
new file mode 100644
index 0000000..e406b88
--- /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;
+}