Add debug_var_dump for debugging.

Author: cscott

src/debug_var_dump.h

@@ -0,0 +1,24 @@
+#ifndef DEBUG_VAR_DUMP_H
+#define DEBUG_VAR_DUMP_H
+extern "C" {
+#include <main/php.h>
+#include <ext/standard/php_var.h>
+}
+
+/* Hack with PHP's buffering to bypass it and vardump directly to stderr. */
+static void debug_var_dump_handler(char *output, uint output_len, char **handled_output, uint *handled_output_len, int mode TSRMLS_DC) {
+    // dump this right to stderr
+    fwrite(output, 1, output_len, stderr);
+    *handled_output = estrdup("");
+    *handled_output_len = 0;
+}
+
+static inline void debug_var_dump(zval *v TSRMLS_DC) {
+    // first push a new buffer context
+    php_output_start_internal("debug_var_dump", 14, debug_var_dump_handler, 64, PHP_OUTPUT_HANDLER_STDFLAGS TSRMLS_CC);
+    // now invoke var_dump
+    php_var_dump(&v, 1 TSRMLS_CC);
+    // now flush/pop the buffer context
+    php_output_end(TSRMLS_C);
+}
+#endif