Better logging in tokenstream

v0/log.c

@@ -2,6 +2,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
+#include <stdarg.h>
 
 static LogError* s_logError = NULL;
 
@@ -17,17 +18,24 @@ void log_error(const char* msg) {
     }
 }
 
-void log_on_line(const char* filename, const char* line_text, int line, int from, int to, const char* msg) {
+void log_on_line(const char* filename, const char* line_text, int line, int from, int to, const char* msg, ...) {
     char line_prefix[32];
     int prefix_len = snprintf(line_prefix, sizeof(line_prefix), "%d| ", line);
     
     int caret_len = to - from + 1;
     if (caret_len < 1) caret_len = 1;
 
+    // Format the message
+    va_list args;
+    va_start(args, msg);
+    char formatted_msg[256];
+    vsnprintf(formatted_msg, sizeof(formatted_msg), msg, args);
+    va_end(args);
+
     size_t total_size = strlen(filename) + 16 + // --- filename ---
                         prefix_len + strlen(line_text) + 2 + // line| text\n
                         prefix_len + from - 1 + caret_len + 2 + // indent + ^^\n
-                        prefix_len + strlen(msg) + 2 + // indent + msg\n
+                        prefix_len + strlen(formatted_msg) + 2 + // indent + msg\n
                         1;
 
     char* buffer = (char*)malloc(total_size);
@@ -44,7 +52,7 @@ void log_on_line(const char* filename, const char* line_text, int line, int from
 
     // Message line
     for (int i = 0; i < prefix_len; i++) *p++ = ' ';
-    p += sprintf(p, "%s\n", msg);
+    p += sprintf(p, "%s\n", formatted_msg);
     
     *p = '\0';