Fallback asprintf: don't truncate output that has a \0 in string

Unlikely to be hit in xrdb, but may affect other uses if this code
gets copied to other programs.

Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>

1 files changed, 12 insertions, 13 deletions

diff --git a/xrdb.c b/xrdb.c
index a183199..6455b93 100644
--- a/xrdb.c
+++ b/xrdb.c
@@ -168,25 +168,24 @@ asprintf(char **ret, const char *format, ...)
     if (len < 0)
         return -1;
 
+    *ret = malloc(len + 1); /* snprintf doesn't count trailing '\0' */
+    if (*ret == NULL)
+        return -1;
+
     if (len < sizeof(buf)) {
-        *ret = strdup(buf);
+        memcpy(*ret, buf, len + 1);
     }
     else {
-        *ret = malloc(len + 1); /* snprintf doesn't count trailing '\0' */
-        if (*ret != NULL) {
-            va_start(ap, format);
-            len = vsnprintf(*ret, len + 1, format, ap);
-            va_end(ap);
-            if (len < 0) {
-                free(*ret);
-                *ret = NULL;
-            }
+        va_start(ap, format);
+        len = vsnprintf(*ret, len + 1, format, ap);
+        va_end(ap);
+        if (len < 0) {
+            free(*ret);
+            *ret = NULL;
+            return -1;
         }
     }
 
-    if (*ret == NULL)
-        return -1;
-
     return len;
 }
 #endif                          /* HAVE_ASPRINTF */