login: add xgetpwnam()

Signed-off-by: Karel Zak <kzak@redhat.com>

1 files changed, 64 insertions, 0 deletions

diff --git a/lib/pwdutils.c b/lib/pwdutils.c
new file mode 100644
index 000000000..58e75a45b
--- /dev/null
+++ b/lib/pwdutils.c
@@ -0,0 +1,64 @@
+#include <stdlib.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;
+
+	if (!pwdbuf || !username)
+		return NULL;
+
+	*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;
+}
+
+
+#ifdef TEST_PROGRAM
+int main(int argc, char *argv[])
+{
+	char *pwdbuf = NULL;
+	struct passwd *pwd = NULL;
+
+	if (argc != 2) {
+		fprintf(stderr, "usage: %s <username>\n", argv[0]);
+		return EXIT_FAILURE;
+	}
+
+	pwd = xgetpwnam(argv[1], &pwdbuf);
+	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(pwdbuf);
+	return EXIT_SUCCESS;
+}
+#endif /* TEST_PROGRAM */