Fixed a bug in CDR file rename

The problem was that the rename() function failed when rotation of the Master.csv was
required due to reaching the maxrow parameter.

This happened, if the temporary CDR file for renaming was in a directory at a different
mount point than Master.csv rename() function was always failed with a 'Cross-device
link' error.

The fix will locate the temporary file in the same directory as the main Master.csv file.

cdr/cdr_csv.c

@@ -147,8 +147,12 @@ static int load_config(int reload)
 		} else if (!strcasecmp(v->name, "maxrow")) {
 			maxrow = atoi(v->value);
 		} else if (!strcasecmp(v->name, "prefdir")) {
+			ast_mutex_lock(&f_lock);
 			snprintf(file_csv_master, sizeof(file_csv_master),
 				"%s/%s/%s", v->value, CSV_LOG_DIR, CSV_MASTER);
+			snprintf(file_csv_temp, sizeof(file_csv_temp),
+				"%s/%s/%s", v->value, CSV_LOG_DIR, CSV_TEMP);
+			ast_mutex_unlock(&f_lock);
 		}
 
 	}
@@ -391,7 +395,10 @@ static int writefile(char *s, char *file_path)
 		fflush(ft);
 		fclose(ft);
 		remove(file_path); /* rm the original file and rename the temp file to it */
-		rename(file_csv_temp, file_path);
+		if (rename(file_csv_temp, file_path)) {
+			ast_log(LOG_ERROR, "Unable to rename %s to %s : %s\n", file_csv_temp, file_path, strerror(errno));
+			return -1;
+		}
 	} else {
 		if (!(f = fopen(file_path, "a"))) {
 			ast_log(LOG_ERROR, "Unable to open file %s : %s\n", file_path, strerror(errno));