| /* vi: set sw=4 ts=4: |
| * |
| * id.c - print real and effective user and group IDs |
| * |
| * Copyright 2012 Sony Network Entertainment, Inc. |
| * |
| * by Tim Bird <tim.bird@am.sony.com> |
| * |
| * See http://opengroup.org/onlinepubs/9699919799/utilities/id.html |
| |
| USE_ID(NEWTOY(id, "nGgru", TOYFLAG_BIN)) |
| |
| config ID |
| bool "id" |
| default y |
| help |
| 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 "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 |
| |
| static void s_or_u(char *s, unsigned u, int done) |
| { |
| if (toys.optflags & FLAG_n) printf("%s", s); |
| else printf("%u", u); |
| if (done) { |
| xputc('\n'); |
| exit(0); |
| } |
| } |
| |
| static void showid(char *header, unsigned u, char *s) |
| { |
| printf("%s%u(%s)", header, u, s); |
| } |
| |
| struct passwd *xgetpwuid(uid_t uid) |
| { |
| struct passwd *pwd = getpwuid(uid); |
| if (!pwd) error_exit(NULL); |
| return pwd; |
| } |
| |
| struct group *xgetgrgid(gid_t gid) |
| { |
| struct group *group = getgrgid(gid); |
| if (!group) error_exit(NULL); |
| return group; |
| } |
| |
| void id_main(void) |
| { |
| int flags = toys.optflags, i, ngroups; |
| struct passwd *pw; |
| struct group *grp; |
| uid_t uid = getuid(), euid = geteuid(); |
| gid_t gid = getgid(), egid = getegid(), *groups; |
| |
| /* check if a username is given */ |
| if (*toys.optargs) { |
| if (!(pw = getpwnam(*toys.optargs))) |
| error_exit("no such user '%s'", *toys.optargs); |
| uid = euid = pw->pw_uid; |
| gid = egid = pw->pw_gid; |
| } |
| |
| i = toys.optflags & FLAG_r; |
| pw = xgetpwuid(i ? uid : euid); |
| if (flags & FLAG_u) s_or_u(pw->pw_name, pw->pw_uid, 1); |
| |
| grp = xgetgrgid(i ? gid : egid); |
| if (flags & FLAG_g) s_or_u(grp->gr_name, grp->gr_gid, 1); |
| |
| if (!(flags & FLAG_G)) { |
| showid("uid=", pw->pw_uid, pw->pw_name); |
| showid(" gid=", grp->gr_gid, grp->gr_name); |
| |
| if (!i) { |
| if (uid != euid) { |
| pw = xgetpwuid(euid); |
| showid(" euid=", pw->pw_uid, pw->pw_name); |
| } |
| if (gid != egid) { |
| grp = xgetgrgid(egid); |
| showid(" egid=", grp->gr_gid, grp->gr_name); |
| } |
| } |
| |
| showid(" groups=", grp->gr_gid, grp->gr_name); |
| } |
| |
| |
| groups = (gid_t *)toybuf; |
| if (0 >= (ngroups = getgroups(sizeof(toybuf)/sizeof(gid_t), groups))) |
| perror_exit(0); |
| |
| for (i = 0; i < ngroups; i++) { |
| xputc(' '); |
| if (!(grp = getgrgid(groups[i]))) perror_msg(0); |
| else if (flags & FLAG_G) |
| s_or_u(grp->gr_name, grp->gr_gid, 0); |
| else if (grp->gr_gid != egid) showid("", grp->gr_gid, grp->gr_name); |
| } |
| xputc('\n'); |
| } |