Fix size rotating, so filenames are in the order of newest to oldest

src/logging.c

@@ -43,7 +43,6 @@ struct UCLogDestination {
                              //this is the base file name (e.g. witout a date or count)
             size_t size; //keeps track of no of bytes written
             struct UCLogRotateSettings rotate;
-            unsigned rotate_count; //current num_file
         } file;
     } type;
 };
@@ -249,7 +248,6 @@ struct UCLogDestination *uc_log_new_file(const char *filename, int log_level, in
     dest->log_location = log_location;
 
     dest->type.file.rotate.policy = UC_LOG_ROTATE_NONE;
-    dest->type.file.rotate_count = 0;
 
    return dest;
 }
@@ -426,9 +424,11 @@ int uc_log_reopen_files(void)
 
         if (dest->dest_type == UC_LDEST_FILE) {
             rc = uc_log_reopen_file(dest);
+            if (rc == 0) {
                 dest->type.file.size = 0;
             }
         }
+    }
 
     pthread_mutex_unlock(&g_log_lock);
 
@@ -599,31 +599,38 @@ void uc_log_destination_set_mask(
 
 //assumes the destination is a UC_LDEST_FILE
 //hold g_log_lock while calling this
-static int uc_log_file_rotate_size(struct UCLogDestination *dest)
+static void uc_log_file_rotate_size(struct UCLogDestination *dest)
 {
     char new_filename[_POSIX_PATH_MAX * 2];
+    char old_filename[_POSIX_PATH_MAX * 2];
+    unsigned int i;
     int rc;
-    int rotate_count;
 
     if (dest->type.file.file_name == NULL) {
-        return 0;
+        return;
     }
 
-    rotate_count = ++dest->type.file.rotate_count;
-    rotate_count %= dest->type.file.rotate.size_settings.num_files;
-
-    snprintf(new_filename, sizeof new_filename, "%s.%d", 
-                                                dest->type.file.file_name, 
-                                                rotate_count);
-
-    rc = rename(dest->type.file.file_name, new_filename);
-    if (rc != -1) {
-        dest->type.file.rotate_count = rotate_count;
+    //rotate existing .num files
+    i = dest->type.file.rotate.size_settings.num_files -1;
+    while (i > 0) {
+        sprintf(new_filename, "%s.%d", dest->type.file.file_name, i);
+        sprintf(old_filename, "%s.%d", dest->type.file.file_name, i - 1);
+        rename(old_filename, new_filename);
+        i--;
     }
 
-    uc_log_reopen_file(dest); //try to reopen the log file regardless if renaming failed
+    sprintf(new_filename, "%s.0", dest->type.file.file_name);
 
-    return rc;
+    //rename current file
+    rename(dest->type.file.file_name, new_filename);
+
+    //re-open current file
+    rc = uc_log_reopen_file(dest); 
+    if (rc == 0) {
+        dest->type.file.size = 0;
+    }
+
+    return;
 }
 
 //assumes the destination is a UC_LDEST_FILE