ubase/util/passwd.c

115 lines
1.8 KiB
C

/* See LICENSE file for copyright and license details. */
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "../text.h"
#include "../util.h"
int
pw_scan(char *bp, struct passwd *pw)
{
char *p;
memset(pw, 0, sizeof(*pw));
/* login name */
p = strsep(&bp, ":");
if (!p || *p == '\0')
goto corrupt;
pw->pw_name = p;
/* passwd */
p = strsep(&bp, ":");
if (!p)
goto corrupt;
pw->pw_passwd = p;
/* uid */
p = strsep(&bp, ":");
if (!p)
goto corrupt;
pw->pw_uid = estrtol(p, 10);
/* gid */
p = strsep(&bp, ":");
if (!p)
goto corrupt;
pw->pw_gid = estrtol(p, 10);
/* user name or comment */
p = strsep(&bp, ":");
if (!p)
goto corrupt;
pw->pw_gecos = p;
/* home directory */
p = strsep(&bp, ":");
if (!p)
goto corrupt;
pw->pw_dir = p;
/* optional shell */
p = strsep(&bp, ":");
if (!p)
goto corrupt;
pw->pw_shell = p;
/* look for redundant entries */
p = strsep(&bp, ":");
if (p)
goto corrupt;
return 0;
corrupt:
weprintf("corrupted passwd entry\n");
return -1;
}
int
pw_copy(int ffd, int tfd, const struct passwd *newpw)
{
struct passwd pw;
char *buf = NULL, *p;
size_t size = 0;
FILE *from, *to;
from = fdopen(ffd, "r");
if (!from) {
weprintf("fdopen:");
return -1;
}
to = fdopen(tfd, "w");
if (!to) {
weprintf("fdopen:");
return -1;
}
while (agetline(&buf, &size, from) != -1) {
p = strdup(buf);
if (!p) {
weprintf("strdup:");
return -1;
}
if (newpw) {
if (pw_scan(p, &pw) < 0)
return -1;
if (strcmp(pw.pw_name, newpw->pw_name) == 0) {
fprintf(to, "%s:%s:%u:%u:%s:%s:%s\n",
newpw->pw_name,
newpw->pw_passwd,
newpw->pw_uid,
newpw->pw_gid,
newpw->pw_gecos,
newpw->pw_dir,
newpw->pw_shell);
continue;
}
}
fprintf(to, "%s", buf);
free(p);
}
fflush(to);
free(buf);
return 0;
}