deluser: size reduction by 60 bytes.

patch from Tito <farmatito@tiscali.it>
This commit is contained in:
Denis Vlasenko 2006-11-27 00:54:59 +00:00
parent bf11e8942d
commit c9bb67787a

View File

@ -12,85 +12,71 @@
#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 = strchr(start, '\n');
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 void del_line_matching(const char *login, const char *filename)
{
char *buffer;
char *line;
FILE *passwd;
Bounds b;
struct stat statbuf;
int len = strlen(login);
int found = 0;
llist_t *plist = NULL;
passwd = fopen_or_warn(filename, "r");
if (!passwd) return;
if ((passwd = fopen_or_warn(filename, "r"))) {
// Remove pointless const.
xstat((char *)filename, &statbuf);
buffer = (char *) xmalloc(statbuf.st_size * sizeof(char));
fread(buffer, statbuf.st_size, sizeof(char), passwd);
fclose(passwd);
/* find the user to remove */
b = boundary(buffer, login);
if (b.stop != 0) {
/* write the file w/o the user */
if ((passwd = fopen_or_warn(filename, "w"))) {
fwrite(buffer, (b.start - 1), sizeof(char), passwd);
fwrite(&buffer[b.stop], (statbuf.st_size - b.stop), sizeof(char), passwd);
fclose(passwd);
}
while ((line = xmalloc_fgets(passwd))) {
if (!strncmp(line, login, len)
&& line[len] == ':'
) {
found++;
free(line);
} else {
bb_error_msg("can't find '%s' in '%s'", login, filename);
llist_add_to_end(&plist, line);
}
}
if (!found) {
bb_error_msg("can't find '%s' in '%s'", login, filename);
if (!ENABLE_FEATURE_CLEAN_UP) return;
goto clean_up;
}
if (ENABLE_FEATURE_CLEAN_UP)
fclose(passwd);
passwd = fopen_or_warn(filename, "w");
if (passwd) {
if (ENABLE_FEATURE_CLEAN_UP) {
clean_up:
while ((line = llist_pop(&plist))) {
if (found) fputs(line, passwd);
free(line);
}
fclose(passwd);
} else {
/* found != 0 here, no need to check */
while ((line = llist_pop(&plist)))
fputs(line, passwd);
}
free(buffer);
}
}
int deluser_main(int argc, char **argv)
{
if (argc != 2) {
if (argc != 2)
bb_show_usage();
} else {
if (ENABLE_DELUSER && applet_name[3] == 'u') {
del_line_matching(argv[1], bb_path_passwd_file);
if (ENABLE_FEATURE_SHADOWPASSWDS)
del_line_matching(argv[1], bb_path_shadow_file);
}
del_line_matching(argv[1], bb_path_group_file);
if (ENABLE_DELUSER
&& (!ENABLE_DELGROUP || applet_name[3] == 'u')
) {
del_line_matching(argv[1], bb_path_passwd_file);
if (ENABLE_FEATURE_SHADOWPASSWDS)
del_line_matching(argv[1], bb_path_gshadow_file);
del_line_matching(argv[1], bb_path_shadow_file);
}
return (EXIT_SUCCESS);
del_line_matching(argv[1], bb_path_group_file);
if (ENABLE_FEATURE_SHADOWPASSWDS)
del_line_matching(argv[1], bb_path_gshadow_file);
return EXIT_SUCCESS;
}
/* $Id: deluser.c,v 1.4 2003/07/14 20:20:45 andersen Exp $ */