Bug 1471900: Change return type of JS_EncodeStringToBuffer to bool. r=jandem

dom/bindings/BindingUtils.cpp

@@ -2893,7 +2893,9 @@ ConvertJSValueToByteString(JSContext* cx, JS::Handle<JS::Value> v,
     return false;
   }
 
-  JS_EncodeStringToBuffer(cx, s, result.BeginWriting(), length);
+  if (!JS_EncodeStringToBuffer(cx, s, result.BeginWriting(), length)) {
+    return false;
+  }
 
   return true;
 }

js/src/jsapi.cpp

@@ -6131,7 +6131,7 @@ JS_GetStringEncodingLength(JSContext* cx, JSString* str)
     return str->length();
 }
 
-JS_PUBLIC_API(size_t)
+JS_PUBLIC_API(bool)
 JS_EncodeStringToBuffer(JSContext* cx, JSString* str, char* buffer, size_t length)
 {
     AssertHeapIsIdle();
@@ -6139,7 +6139,7 @@ JS_EncodeStringToBuffer(JSContext* cx, JSString* str, char* buffer, size_t lengt
 
     JSLinearString* linear = str->ensureLinear(cx);
     if (!linear)
-         return size_t(-1);
+        return false;
 
     JS::AutoCheckCannotGC nogc;
     size_t writeLength = Min(linear->length(), length);
@@ -6151,7 +6151,7 @@ JS_EncodeStringToBuffer(JSContext* cx, JSString* str, char* buffer, size_t lengt
         for (size_t i = 0; i < writeLength; i++)
             buffer[i] = char(src[i]);
     }
-    return linear->length();
+    return true;
 }
 
 JS_PUBLIC_API(JS::Symbol*)

js/src/jsapi.h

@@ -4636,7 +4636,7 @@ JS_GetStringEncodingLength(JSContext* cx, JSString* str);
  * length parameter, the string will be cut and only length bytes will be
  * written into the buffer.
  */
-JS_PUBLIC_API(size_t)
+MOZ_MUST_USE JS_PUBLIC_API(bool)
 JS_EncodeStringToBuffer(JSContext* cx, JSString* str, char* buffer, size_t length);
 
 class MOZ_RAII JSAutoByteString

js/xpconnect/src/XPCConvert.cpp

@@ -642,7 +642,10 @@ XPCConvert::JSData2Native(void* d, HandleValue s,
         if (!buffer) {
             return false;
         }
-        JS_EncodeStringToBuffer(cx, str, buffer, length);
+        if (!JS_EncodeStringToBuffer(cx, str, buffer, length)) {
+            free(buffer);
+            return false;
+        }
         buffer[length] = '\0';
         *((void**)d) = buffer;
         return true;
@@ -750,7 +753,9 @@ XPCConvert::JSData2Native(void* d, HandleValue s,
         if (rs->Length() != uint32_t(length)) {
             return false;
         }
-        JS_EncodeStringToBuffer(cx, str, rs->BeginWriting(), length);
+        if (!JS_EncodeStringToBuffer(cx, str, rs->BeginWriting(), length)) {
+            return false;
+        }
 
         return true;
     }