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/* This test was ripped out of GNU 'id' from coreutils-5.0
* by Erik Andersen.
*
*
* id is Copyright (C) 1989-2003 Free Software Foundation, Inc.
* and licensed under the GPL v2 or later, and was written by
* Arnold Robbins, with a major rewrite by David MacKenzie,
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <pwd.h>
#include <grp.h>
#include <err.h>
/* The number of errors encountered so far. */
static int problems = 0;
/* Print the name or value of group ID GID. */
static void print_group(gid_t gid)
{
struct group *grp = NULL;
grp = getgrgid(gid);
if (grp == NULL) {
warn("cannot find name for group ID %u", gid);
problems++;
}
if (grp == NULL)
printf("%u", (unsigned)gid);
else
printf("%s", grp->gr_name);
}
static int xgetgroups(gid_t gid, int *n_groups, gid_t ** groups)
{
int max_n_groups;
int ng;
gid_t *g;
int fail = 0;
max_n_groups = getgroups(0, NULL);
/* Add 1 just in case max_n_groups is zero. */
g = (gid_t *) malloc(max_n_groups * sizeof(gid_t) + 1);
if (g == NULL)
err(EXIT_FAILURE, "out of memory");
ng = getgroups(max_n_groups, g);
if (ng < 0) {
warn("cannot get supplemental group list");
++fail;
free(g);
}
if (!fail) {
*n_groups = ng;
*groups = g;
}
return fail;
}
/* Print all of the distinct groups the user is in. */
int main(int argc, char *argv[])
{
struct passwd *pwd;
pwd = getpwuid(getuid());
if (pwd == NULL)
problems++;
print_group(getgid());
if (getegid() != getgid()) {
putchar(' ');
print_group(getegid());
}
{
int n_groups = 0;
gid_t *groups;
register int i;
if (xgetgroups((pwd ? pwd->pw_gid : (gid_t) - 1),
&n_groups, &groups)) {
return ++problems;
}
for (i = 0; i < n_groups; i++)
if (groups[i] != getgid() && groups[i] != getegid()) {
putchar(' ');
print_group(groups[i]);
}
free(groups);
}
putchar('\n');
return (problems != 0);
}
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