From afa03a470ef90a53f2b59a8175f77afdb6b5a651 Mon Sep 17 00:00:00 2001
From: Bob Weinand <bobwei9@hotmail.com>
Date: Thu, 20 Feb 2014 17:39:58 +0100
Subject: [PATCH] Use nicer output for characters < 32 and > 126 in exception
 strings Using question marks might confuse more than it helps. Users are
 wondering what happened to their string...

---
 Zend/zend_exceptions.c | 61 +++++++++++++++++++++++++++++++++++++++---
 1 file changed, 58 insertions(+), 3 deletions(-)

diff --git a/Zend/zend_exceptions.c b/Zend/zend_exceptions.c
index 2ef74ad106f..ced1ebf6397 100644
--- a/Zend/zend_exceptions.c
+++ b/Zend/zend_exceptions.c
@@ -360,6 +360,11 @@ ZEND_METHOD(error_exception, getSeverity)
 		}                                                               \
 	}
 
+
+#define TRACE_ARG_APPEND(vallen)								\
+	*str = (char*)erealloc(*str, *len + 1 + vallen);					\
+	memcpy((*str) + *len - l_added + 1 + vallen, (*str) + *len - l_added + 1, l_added);
+
 /* }}} */
 
 static int _build_trace_args(zval **arg TSRMLS_DC, int num_args, va_list args, zend_hash_key *hash_key) /* {{{ */
@@ -371,7 +376,7 @@ static int _build_trace_args(zval **arg TSRMLS_DC, int num_args, va_list args, z
 	len = va_arg(args, int*);
 
 	/* the trivial way would be to do:
-	 * conver_to_string_ex(arg);
+	 * convert_to_string_ex(arg);
 	 * append it and kill the now tmp arg.
 	 * but that could cause some E_NOTICE and also damn long lines.
 	 */
@@ -394,8 +399,58 @@ static int _build_trace_args(zval **arg TSRMLS_DC, int num_args, va_list args, z
 				l_added += 3 + 1;
 			}
 			while (--l_added) {
-				if ((*str)[*len - l_added] < 32) {
-					(*str)[*len - l_added] = '?';
+				unsigned char chr = (*str)[*len - l_added];
+				if (chr < 32 || chr == '\\' || chr > 126) {
+					(*str)[*len - l_added] = '\\';
+
+					switch (chr) {
+						case '\n':
+							TRACE_ARG_APPEND(1);
+							(*str)[++(*len) - l_added] = 'n';
+							break;
+						case '\r':
+							TRACE_ARG_APPEND(1);
+							(*str)[++(*len) - l_added] = 'r';
+							break;
+						case '\t':
+							TRACE_ARG_APPEND(1);
+							(*str)[++(*len) - l_added] = 't';
+							break;
+						case '\f':
+							TRACE_ARG_APPEND(1);
+							(*str)[++(*len) - l_added] = 'f';
+							break;
+						case '\v':
+							TRACE_ARG_APPEND(1);
+							(*str)[++(*len) - l_added] = 'v';
+							break;
+#ifndef PHP_WIN32
+						case '\e':
+#else
+						case VK_ESCAPE:
+#endif
+							TRACE_ARG_APPEND(1);
+							(*str)[++(*len) - l_added] = 'e';
+							break;
+						case '\\':
+							TRACE_ARG_APPEND(1);
+							(*str)[++(*len) - l_added] = '\\';
+							break;
+						default:
+							TRACE_ARG_APPEND(3);
+							(*str)[*len - l_added + 1] = 'x';
+							if ((chr >> 4) < 10) {
+								(*str)[*len - l_added + 2] = (chr >> 4) + '0';
+							} else {
+								(*str)[*len - l_added + 2] = (chr >> 4) + 'A' - 10;
+							}
+							if (chr % 16 < 10) {
+								(*str)[*len - l_added + 3] = chr % 16 + '0';
+							} else {
+								(*str)[*len - l_added + 3] = chr % 16 + 'A' - 10;
+							}
+							*len += 3;
+					}
 				}
 			}
 			break;