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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 19:10:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 19:10:49 +0000
commitcfe5e3905201349e9cf3f95d52ff4bd100bde37d (patch)
treed0baf160cbee3195249d095f85e52d20c21acf02 /lib/pwdutils.c
parentInitial commit. (diff)
downloadutil-linux-cfe5e3905201349e9cf3f95d52ff4bd100bde37d.tar.xz
util-linux-cfe5e3905201349e9cf3f95d52ff4bd100bde37d.zip
Adding upstream version 2.39.3.upstream/2.39.3
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/pwdutils.c')
-rw-r--r--lib/pwdutils.c158
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 */