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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 14:30:35 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 14:30:35 +0000 |
commit | 378c18e5f024ac5a8aef4cb40d7c9aa9633d144c (patch) | |
tree | 44dfb6ca500d32cabd450649b322a42e70a30683 /lib/pwdutils.c | |
parent | Initial commit. (diff) | |
download | util-linux-378c18e5f024ac5a8aef4cb40d7c9aa9633d144c.tar.xz util-linux-378c18e5f024ac5a8aef4cb40d7c9aa9633d144c.zip |
Adding upstream version 2.38.1.upstream/2.38.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | lib/pwdutils.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/lib/pwdutils.c b/lib/pwdutils.c new file mode 100644 index 0000000..1c1f13e --- /dev/null +++ b/lib/pwdutils.c @@ -0,0 +1,158 @@ +/* + * No copyright is claimed. This code is in the public domain; do with + * it what you wish. + */ +#include <stdlib.h> +#include <assert.h> + +#include "c.h" +#include "pwdutils.h" +#include "xalloc.h" + +/* Returns allocated passwd and allocated pwdbuf to store passwd strings + * fields. In case of error returns NULL and set errno, for unknown user set + * errno to EINVAL + */ +struct passwd *xgetpwnam(const char *username, char **pwdbuf) +{ + struct passwd *pwd = NULL, *res = NULL; + int rc; + + assert(pwdbuf); + assert(username); + + *pwdbuf = xmalloc(UL_GETPW_BUFSIZ); + pwd = xcalloc(1, sizeof(struct passwd)); + + errno = 0; + rc = getpwnam_r(username, pwd, *pwdbuf, UL_GETPW_BUFSIZ, &res); + if (rc != 0) { + errno = rc; + goto failed; + } + if (!res) { + errno = EINVAL; + goto failed; + } + return pwd; +failed: + free(pwd); + free(*pwdbuf); + return NULL; +} + +/* Returns allocated group and allocated grpbuf to store group strings + * fields. In case of error returns NULL and set errno, for unknown group set + * errno to EINVAL + */ +struct group *xgetgrnam(const char *groupname, char **grpbuf) +{ + struct group *grp = NULL, *res = NULL; + int rc; + + assert(grpbuf); + assert(groupname); + + *grpbuf = xmalloc(UL_GETPW_BUFSIZ); + grp = xcalloc(1, sizeof(struct group)); + + errno = 0; + rc = getgrnam_r(groupname, grp, *grpbuf, UL_GETPW_BUFSIZ, &res); + if (rc != 0) { + errno = rc; + goto failed; + } + if (!res) { + errno = EINVAL; + goto failed; + } + return grp; +failed: + free(grp); + free(*grpbuf); + return NULL; +} + +struct passwd *xgetpwuid(uid_t uid, char **pwdbuf) +{ + struct passwd *pwd = NULL, *res = NULL; + int rc; + + assert(pwdbuf); + + *pwdbuf = xmalloc(UL_GETPW_BUFSIZ); + pwd = xcalloc(1, sizeof(struct passwd)); + + errno = 0; + rc = getpwuid_r(uid, pwd, *pwdbuf, UL_GETPW_BUFSIZ, &res); + if (rc != 0) { + errno = rc; + goto failed; + } + if (!res) { + errno = EINVAL; + goto failed; + } + return pwd; +failed: + free(pwd); + free(*pwdbuf); + return NULL; +} + +char *xgetlogin(void) +{ + struct passwd *pw = NULL; + uid_t ruid; + + /* GNU Hurd implementation has an extension where a process can exist in a + * non-conforming environment, and thus be outside the realms of POSIX + * process identifiers; on this platform, getuid() fails with a status of + * (uid_t)(-1) and sets errno if a program is run from a non-conforming + * environment. + * + * http://austingroupbugs.net/view.php?id=511 + * + * The same implementation is useful for other systems, since getlogin(3) + * shouldn't be used as actual identification. + */ + errno = 0; + ruid = getuid(); + + if (errno == 0) + pw = getpwuid(ruid); + if (pw && pw->pw_name && *pw->pw_name) + return xstrdup(pw->pw_name); + + return NULL; +} + +#ifdef TEST_PROGRAM +int main(int argc, char *argv[]) +{ + char *buf = NULL; + struct passwd *pwd = NULL; + + if (argc != 2) { + fprintf(stderr, "usage: %s <username>\n", argv[0]); + return EXIT_FAILURE; + } + + pwd = xgetpwnam(argv[1], &buf); + if (!pwd) + err(EXIT_FAILURE, "failed to get %s pwd entry", argv[1]); + + printf("Username: %s\n", pwd->pw_name); + printf("UID: %d\n", pwd->pw_uid); + printf("HOME: %s\n", pwd->pw_dir); + printf("GECO: %s\n", pwd->pw_gecos); + + free(pwd); + free(buf); + + printf("Current: %s\n", (buf = xgetlogin())); + free(buf); + + return EXIT_SUCCESS; +} +#endif /* TEST_PROGRAM */ |