dma: restructure set_username

Restructure to perform early exit and check for strdup() error.

diff --git a/libexec/dma/dma.c b/libexec/dma/dma.c
index 9ca7f99..4633b0c 100644 (file)
--- a/libexec/dma/dma.c
+++ b/libexec/dma/dma.c
@@ -134,26 +134,31 @@ static void
 set_username(void)
 {
        struct passwd *pwd;
-       char *u;
+       char *u = NULL;
 
        uid = getuid();
        username = check_username(getlogin(), uid);
-       if (username == NULL)
-               username = check_username(getenv("LOGNAME"), uid);
-       if (username == NULL)
-               username = check_username(getenv("USER"), uid);
-       if (username == NULL) {
-               pwd = getpwuid(uid);
-               if (pwd != NULL && pwd->pw_name != NULL &&
-                   pwd->pw_name[0] != '\0')
-                       username = check_username(strdup(pwd->pw_name), uid);
-       }
-       if (username == NULL) {
-               asprintf(&u, "%ld", (long)uid);
-               username = u;
+       if (username != NULL)
+               return;
+       username = check_username(getenv("LOGNAME"), uid);
+       if (username != NULL)
+               return;
+       username = check_username(getenv("USER"), uid);
+       if (username != NULL)
+               return;
+       pwd = getpwuid(uid);
+       if (pwd != NULL && pwd->pw_name != NULL && pwd->pw_name[0] != '\0' &&
+           (u = strdup(pwd->pw_name)) != NULL) {
+               username = check_username(u, uid);
+               if (username != NULL)
+                       return;
+               else
+                       free(u);
        }
-       if (username == NULL)
-               username = "unknown-or-invalid-username";
+       asprintf(__DECONST(void *, &username), "%ld", (long)uid);
+       if (username != NULL)
+               return;
+       username = "unknown-or-invalid-username";
 }
 
 static char *