Limit length of strings copied into a heap snapshot

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index e20893615ccc398af8a2cb5ce53ed9a83e4ef313..44ca9e70e150909098b43eb8bf9cbb26bcdac833 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -5826,11 +5826,9 @@ SmartArrayPointer<char> String::ToCString(AllowNullsFlag allow_nulls,
   buffer->Reset(offset, this);
   int character_position = offset;
   int utf8_bytes = 0;
-  while (buffer->has_more()) {
+  while (buffer->has_more() && character_position < offset + length) {
     uint16_t character = buffer->GetNext();
-    if (character_position < offset + length) {
-      utf8_bytes += unibrow::Utf8::Length(character);
-    }
+    utf8_bytes += unibrow::Utf8::Length(character);
     character_position++;

[mnaganov (inactive), 2011/11/09 11:45:23]

This can be moved up into the loop clause.

   }
 
@@ -5845,15 +5843,13 @@ SmartArrayPointer<char> String::ToCString(AllowNullsFlag allow_nulls,
   buffer->Seek(offset);
   character_position = offset;
   int utf8_byte_position = 0;
-  while (buffer->has_more()) {
+  while (buffer->has_more() && character_position < offset + length) {
     uint16_t character = buffer->GetNext();
-    if (character_position < offset + length) {
-      if (allow_nulls == DISALLOW_NULLS && character == 0) {
-        character = ' ';
-      }
-      utf8_byte_position +=
-          unibrow::Utf8::Encode(result + utf8_byte_position, character);
+    if (allow_nulls == DISALLOW_NULLS && character == 0) {
+      character = ' ';
     }
+    utf8_byte_position +=
+        unibrow::Utf8::Encode(result + utf8_byte_position, character);
     character_position++;

[mnaganov (inactive), 2011/11/09 11:45:23]

Same here.

   }
   result[utf8_byte_position] = 0;