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/* vi: set sw=4 ts=4: */
/*
* deluser (remove lusers from the system ;) for TinyLogin
*
* Copyright (C) 1999 by Lineo, inc. and John Beppu
* Copyright (C) 1999,2000,2001 by John Beppu <beppu@codepoet.org>
*
* 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
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <sys/stat.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "busybox.h"
/* where to start and stop deletion */
typedef struct {
size_t start;
size_t stop;
} Bounds;
/* An interesting side-effect of boundary()'s
* implementation is that the first user (typically root)
* cannot be removed. Let's call it a feature. */
static inline Bounds boundary(const char *buffer, const char *login)
{
char needle[256];
char *start;
char *stop;
Bounds b;
snprintf(needle, 256, "\n%s:", login);
needle[255] = 0;
start = strstr(buffer, needle);
if (!start) {
b.start = 0;
b.stop = 0;
return b;
}
start++;
stop = index(start, '\n'); /* index is a BSD-ism */
b.start = start - buffer;
b.stop = stop - buffer;
return b;
}
/* grep -v ^login (except it only deletes the first match) */
/* ...in fact, I think I'm going to simplify this later */
static int del_line_matching(const char *login, const char *filename)
{
char *buffer;
FILE *passwd;
size_t len;
Bounds b;
struct stat statbuf;
/* load into buffer */
passwd = fopen(filename, "r");
if (!passwd) {
return 1;
}
stat(filename, &statbuf);
len = statbuf.st_size;
buffer = (char *) malloc(len * sizeof(char));
if (!buffer) {
fclose(passwd);
return 1;
}
fread(buffer, len, sizeof(char), passwd);
fclose(passwd);
/* find the user to remove */
b = boundary(buffer, login);
if (b.stop == 0) {
free(buffer);
return 1;
}
/* write the file w/o the user */
passwd = fopen(filename, "w");
if (!passwd) {
return 1;
}
fwrite(buffer, (b.start - 1), sizeof(char), passwd);
fwrite(&buffer[b.stop], (len - b.stop), sizeof(char), passwd);
fclose(passwd);
return 0;
}
/* $Id: delline.c,v 1.1 2003/07/14 20:20:45 andersen Exp $ */
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