Convert codebase to C89 compatibility and update test scripts

v0/util.c

@@ -2,26 +2,45 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <stdarg.h>
+
+/* Portable va_copy fallback for pre-C99 or platforms without va_copy. */
+#ifndef va_copy
+# if defined(__va_copy)
+#  define va_copy(dest, src) __va_copy(dest, src)
+# else
+#  define va_copy(dest, src) ((dest) = (src))
+# endif
+#endif
 
 char* format_string_va(const char* fmt, va_list args) {
-    if (!fmt) return NULL;
+    /* Declarations first to satisfy -std=c89 */
     va_list args_copy;
+    int needed;
+    char* buf;
+
+    if (!fmt) return NULL;
+
     va_copy(args_copy, args);
-    int needed = vsnprintf(NULL, 0, fmt, args_copy);
+    needed = vsnprintf(NULL, 0, fmt, args_copy);
     va_end(args_copy);
     if (needed < 0) return NULL;
 
-    char* buf = (char*)malloc((size_t)needed + 1);
+    buf = (char*)malloc((size_t)needed + 1);
     if (!buf) return NULL;
     vsnprintf(buf, (size_t)needed + 1, fmt, args);
     return buf;
 }
 
 char* format_string(const char* fmt, ...) {
-    if (!fmt) return NULL;
+    /* Declarations first to satisfy -std=c89 */
     va_list args;
+    char* s;
+
+    if (!fmt) return NULL;
+
     va_start(args, fmt);
-    char* s = format_string_va(fmt, args);
+    s = format_string_va(fmt, args);
     va_end(args);
     return s;
 }