Updating to new OTS repo from https://github.com/khaledhosny/ots.git

src/ltsh.cc

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ltsh.h"
 
 #include "maxp.h"
 
 // LTSH - Linear Threshold
 // http://www.microsoft.com/typography/otspec/ltsh.htm
 
-#define DROP_THIS_TABLE \
-  do { delete file->ltsh; file->ltsh = 0; } while (0)
+#define TABLE_NAME "LTSH"
+
+#define DROP_THIS_TABLE(...) \
+  do { \
+    delete file->ltsh; \
+    file->ltsh = 0; \
+    OTS_FAILURE_MSG_(file, TABLE_NAME ": " __VA_ARGS__); \
+    OTS_FAILURE_MSG("Table discarded"); \
+  } while (0)
 
 namespace ots {
 
 bool ots_ltsh_parse(OpenTypeFile *file, const uint8_t *data, size_t length) {
   Buffer table(data, length);
 
   if (!file->maxp) {
-    return OTS_FAILURE();
+    return OTS_FAILURE_MSG("Missing maxp table from font needed by ltsh");
   }
 
   OpenTypeLTSH *ltsh = new OpenTypeLTSH;
   file->ltsh = ltsh;
 
   uint16_t num_glyphs = 0;
   if (!table.ReadU16(&ltsh->version) ||
       !table.ReadU16(&num_glyphs)) {
-    return OTS_FAILURE();
+    return OTS_FAILURE_MSG("Failed to read ltsh header");
   }
 
   if (ltsh->version != 0) {
-    OTS_WARNING("bad version: %u", ltsh->version);
-    DROP_THIS_TABLE;
+    DROP_THIS_TABLE("bad version: %u", ltsh->version);
     return true;
   }
 
   if (num_glyphs != file->maxp->num_glyphs) {
-    OTS_WARNING("bad num_glyphs: %u", num_glyphs);
-    DROP_THIS_TABLE;
+    DROP_THIS_TABLE("bad num_glyphs: %u", num_glyphs);
     return true;
   }
 
   ltsh->ypels.reserve(num_glyphs);
   for (unsigned i = 0; i < num_glyphs; ++i) {
     uint8_t pel = 0;
     if (!table.ReadU8(&pel)) {
-      return OTS_FAILURE();
+      return OTS_FAILURE_MSG("Failed to read pixels for glyph %d", i);
     }
     ltsh->ypels.push_back(pel);
   }
 
   return true;
 }
 
 bool ots_ltsh_should_serialise(OpenTypeFile *file) {
   if (!file->glyf) return false;  // this table is not for CFF fonts.
   return file->ltsh != NULL;
 }
 
 bool ots_ltsh_serialise(OTSStream *out, OpenTypeFile *file) {
   const OpenTypeLTSH *ltsh = file->ltsh;
+
   const uint16_t num_ypels = static_cast<uint16_t>(ltsh->ypels.size());
   if (num_ypels != ltsh->ypels.size() ||
       !out->WriteU16(ltsh->version) ||
       !out->WriteU16(num_ypels)) {
-    return OTS_FAILURE();
+    return OTS_FAILURE_MSG("Failed to write pels size");
   }
   for (uint16_t i = 0; i < num_ypels; ++i) {
     if (!out->Write(&(ltsh->ypels[i]), 1)) {
-      return OTS_FAILURE();
+      return OTS_FAILURE_MSG("Failed to write pixel size for glyph %d", i);
     }
   }
 
   return true;
 }
 
 void ots_ltsh_free(OpenTypeFile *file) {
   delete file->ltsh;
 }
 
 }  // namespace ots
+
+#undef TABLE_NAME
+#undef DROP_THIS_TABLE