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-rw-r--r--toys/id.c140
1 files changed, 128 insertions, 12 deletions
diff --git a/toys/id.c b/toys/id.c
index 6f0d12fd..6ae3efe5 100644
--- a/toys/id.c
+++ b/toys/id.c
@@ -8,49 +8,165 @@
*
* See http://www.opengroup.org/onlinepubs/009695399/utilities/id.html
-USE_ID(NEWTOY(id, "gru", TOYFLAG_BIN))
+USE_ID(NEWTOY(id, "nGgru", TOYFLAG_BIN))
config ID
bool "id"
- default n
+ default y
help
- usage: id [-gru]
+ usage: id [-nGgru]
Print user and group ID.
+ -n print names instead of numeric IDs (to be used with -Ggu)
+ -G Show only the group IDs
-g Show only the effective group ID
-r Show real ID instead of effective ID
-u Show only the effective user ID
*/
+#include <sys/types.h>
+#include <pwd.h>
+#include <grp.h>
#include "toys.h"
+#define FLAG_n (1<<4)
+#define FLAG_G (1<<3)
#define FLAG_g (1<<2)
#define FLAG_r (1<<1)
#define FLAG_u 1
+void
+pretty_print(struct passwd *pw, struct group *grp, struct group **grps, int n)
+{
+ int i;
+ printf("uid= %d(%s) gid= %d(%s)", pw->pw_uid, pw->pw_name,
+ grp->gr_gid, grp->gr_name);
+ if (n) {
+ printf(" groups= ");
+ }
+ for (i = 0; i < n; i++) {
+ printf("%d(%s)%s", grps[i]->gr_gid, grps[i]->gr_name,
+ (i < n-1) ? ",": "");
+ }
+ printf("\n");
+}
+
void id_main(void)
{
int flags = toys.optflags;
+ struct passwd *pw;
+ struct group *grp;
+ struct group **grps;
uid_t uid;
gid_t gid;
+ gid_t *groups;
+ int i;
+ int ngroups;
+ char *username;
- /* show effective, unless user specifies real */
- uid = geteuid();
- gid = getegid();
+ /* check if a username is given */
+ if (*toys.optargs) {
+ username = *(toys.optargs);
+ pw = getpwnam(username);
+ if (!pw) {
+ printf("id: %s: no such user\n", username);
+ toys.exitval = 1;
+ return;
+ }
+ uid = pw->pw_uid;
+ gid = pw->pw_gid;
+ } else {
+ /* show effective, unless user specifies real */
+ if (flags & FLAG_r) {
+ uid = getuid();
+ gid = getgid();
+ } else {
+ uid = geteuid();
+ gid = getegid();
+ }
+ }
- if (flags & FLAG_r) {
- uid = getuid();
- gid = getgid();
+ pw = getpwuid(uid);
+ if (!pw) {
+ perror("id");
+ toys.exitval = 1;
+ return;
+ }
+
+ grp = getgrgid(pw->pw_gid);
+ if (!grp) {
+ perror("id");
+ toys.exitval = 1;
+ return;
}
+
if (flags & FLAG_u) {
- printf("%d\n", uid);
+ if (flags & FLAG_n)
+ printf("%s\n", pw->pw_name);
+ else
+ printf("%d\n", pw->pw_uid);
return;
}
if (flags & FLAG_g) {
- printf("%d\n", gid);
+ if (flags & FLAG_n)
+ printf("%s\n", grp->gr_name);
+ else
+ printf("%d\n", grp->gr_gid);
return;
}
- printf("%d %d\n", uid, gid);
+
+
+ if (flags & FLAG_r) {
+ printf("-r can only be used in combination with -u or -g\n");
+ toys.exitval = 1;
+ return;
+ }
+ ngroups = sysconf(_SC_NGROUPS_MAX);
+ /* fallback for number of groups to 32 */
+ if (ngroups < 0)
+ ngroups = 32;
+ groups = malloc(ngroups * sizeof(gid_t));
+ if (!groups) {
+ perror("id");
+ toys.exitval = 1;
+ return;
+ }
+ if (getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups) < 0) {
+ perror("id");
+ toys.exitval = 1;
+ return;
+ }
+ grps = malloc(ngroups * sizeof(struct group *));
+ for (i = 0; i < ngroups; i++) {
+ struct group *tmp;
+ grps[i] = malloc(sizeof(struct group));
+ size_t f = sysconf(_SC_GETGR_R_SIZE_MAX);
+ char *buf = malloc(f);
+ if (getgrgid_r(groups[i], grps[i], buf, f, &tmp) < 0) {
+ perror("id");
+ continue;
+ }
+ if (tmp == NULL) {
+ perror("id");
+ continue;
+ }
+ }
+
+ if (flags & FLAG_G) {
+ for (i = 0; i < ngroups; i++) {
+ if (flags & FLAG_n)
+ printf("%s%s", !i ? "" : " ", grps[i]->gr_name);
+ else
+ printf("%s%d", !i ? "" : " ", grps[i]->gr_gid);
+ }
+ printf("\n");
+ return;
+ }
+
+ pretty_print(pw, grp, grps, ngroups);
+ for (i=0; i < ngroups; i++)
+ free(grps[i]);
+
}