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

src/os2.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 "os2.h"
 
 #include "head.h"
 
 // OS/2 - OS/2 and Windows Metrics
-// http://www.microsoft.com/opentype/otspec/os2.htm
+// http://www.microsoft.com/typography/otspec/os2.htm
+
+#define TABLE_NAME "OS/2"
 
 namespace ots {
 
 bool ots_os2_parse(OpenTypeFile *file, const uint8_t *data, size_t length) {
   Buffer table(data, length);
 
   OpenTypeOS2 *os2 = new OpenTypeOS2;
   file->os2 = os2;
 
   if (!table.ReadU16(&os2->version) ||
       !table.ReadS16(&os2->avg_char_width) ||
       !table.ReadU16(&os2->weight_class) ||
       !table.ReadU16(&os2->width_class) ||
       !table.ReadU16(&os2->type) ||
       !table.ReadS16(&os2->subscript_x_size) ||
       !table.ReadS16(&os2->subscript_y_size) ||
       !table.ReadS16(&os2->subscript_x_offset) ||
       !table.ReadS16(&os2->subscript_y_offset) ||
       !table.ReadS16(&os2->superscript_x_size) ||
       !table.ReadS16(&os2->superscript_y_size) ||
       !table.ReadS16(&os2->superscript_x_offset) ||
       !table.ReadS16(&os2->superscript_y_offset) ||
       !table.ReadS16(&os2->strikeout_size) ||
       !table.ReadS16(&os2->strikeout_position) ||
       !table.ReadS16(&os2->family_class)) {
-    return OTS_FAILURE();
+    return OTS_FAILURE_MSG("Failed toi read basic os2 elements");
   }
 
   if (os2->version > 4) {
-    return OTS_FAILURE();
+    return OTS_FAILURE_MSG("os2 version too high %d", os2->version);
   }
 
   // Some linux fonts (e.g., Kedage-t.ttf and LucidaSansDemiOblique.ttf) have
   // weird weight/width classes. Overwrite them with FW_NORMAL/1/9.
   if (os2->weight_class < 100 ||
       os2->weight_class > 900 ||
       os2->weight_class % 100) {
     OTS_WARNING("bad weight: %u", os2->weight_class);
     os2->weight_class = 400;  // FW_NORMAL
   }
@@ skipping 36 matching lines @@
     OTS_WARNING("bad superscript_y_size: %d", os2->superscript_y_size);
     os2->superscript_y_size = 0;
   }
   if (os2->strikeout_size < 0) {
     OTS_WARNING("bad strikeout_size: %d", os2->strikeout_size);
     os2->strikeout_size = 0;
   }
 
   for (unsigned i = 0; i < 10; ++i) {
     if (!table.ReadU8(&os2->panose[i])) {
-      return OTS_FAILURE();
+      return OTS_FAILURE_MSG("Failed to read panose in os2 table");
     }
   }
 
   if (!table.ReadU32(&os2->unicode_range_1) ||
       !table.ReadU32(&os2->unicode_range_2) ||
       !table.ReadU32(&os2->unicode_range_3) ||
       !table.ReadU32(&os2->unicode_range_4) ||
       !table.ReadU32(&os2->vendor_id) ||
       !table.ReadU16(&os2->selection) ||
       !table.ReadU16(&os2->first_char_index) ||
       !table.ReadU16(&os2->last_char_index) ||
       !table.ReadS16(&os2->typo_ascender) ||
       !table.ReadS16(&os2->typo_descender) ||
       !table.ReadS16(&os2->typo_linegap) ||
       !table.ReadU16(&os2->win_ascent) ||
       !table.ReadU16(&os2->win_descent)) {
-    return OTS_FAILURE();
+    return OTS_FAILURE_MSG("Failed to read more basic os2 fields");
   }
 
   // If bit 6 is set, then bits 0 and 5 must be clear.
   if (os2->selection & 0x40) {
     os2->selection &= 0xffdeu;
   }
 
   // the settings of bits 0 and 1 must be reflected in the macStyle bits
   // in the 'head' table.
   if (!file->head) {
-    return OTS_FAILURE();
+    return OTS_FAILURE_MSG("Head table missing from font as needed by os2 table");
   }
   if ((os2->selection & 0x1) &&
       !(file->head->mac_style & 0x2)) {
     OTS_WARNING("adjusting Mac style (italic)");
     file->head->mac_style |= 0x2;
   }
   if ((os2->selection & 0x2) &&
       !(file->head->mac_style & 0x4)) {
     OTS_WARNING("adjusting Mac style (underscore)");
     file->head->mac_style |= 0x4;
   }
 
   // While bit 6 on implies that bits 0 and 1 of macStyle are clear,
   // the reverse is not true.
   if ((os2->selection & 0x40) &&
       (file->head->mac_style & 0x3)) {
     OTS_WARNING("adjusting Mac style (regular)");
     file->head->mac_style &= 0xfffcu;
   }
 
   if ((os2->version < 4) &&
       (os2->selection & 0x300)) {
     // bit 8 and 9 must be unset in OS/2 table versions less than 4.
-    return OTS_FAILURE();
+    return OTS_FAILURE_MSG("OS2 version %d incompatible with selection %d", os2->version, os2->selection);
   }
 
   // mask reserved bits. use only 0..9 bits.
   os2->selection &= 0x3ff;
 
   if (os2->first_char_index > os2->last_char_index) {
-    return OTS_FAILURE();
+    return OTS_FAILURE_MSG("first char index %d > last char index %d in os2", os2->first_char_index, os2->last_char_index);
   }
   if (os2->typo_linegap < 0) {
     OTS_WARNING("bad linegap: %d", os2->typo_linegap);
     os2->typo_linegap = 0;
   }
 
   if (os2->version < 1) {
     // http://www.microsoft.com/typography/otspec/os2ver0.htm
     return true;
   }
 
   if (length < offsetof(OpenTypeOS2, code_page_range_2)) {
     OTS_WARNING("bad version number: %u", os2->version);
     // Some fonts (e.g., kredit1.ttf and quinquef.ttf) have weird version
     // numbers. Fix them.
     os2->version = 0;
     return true;
   }
 
   if (!table.ReadU32(&os2->code_page_range_1) ||
       !table.ReadU32(&os2->code_page_range_2)) {
-    return OTS_FAILURE();
+    return OTS_FAILURE_MSG("Failed to read codepage ranges");
   }
 
   if (os2->version < 2) {
     // http://www.microsoft.com/typography/otspec/os2ver1.htm
     return true;
   }
 
   if (length < offsetof(OpenTypeOS2, max_context)) {
     OTS_WARNING("bad version number: %u", os2->version);
     // some Japanese fonts (e.g., mona.ttf) have weird version number.
     // fix them.
     os2->version = 1;
     return true;
   }
 
   if (!table.ReadS16(&os2->x_height) ||
       !table.ReadS16(&os2->cap_height) ||
       !table.ReadU16(&os2->default_char) ||
       !table.ReadU16(&os2->break_char) ||
       !table.ReadU16(&os2->max_context)) {
-    return OTS_FAILURE();
+    return OTS_FAILURE_MSG("Failed to read os2 version 2 information");
   }
 
   if (os2->x_height < 0) {
     OTS_WARNING("bad x_height: %d", os2->x_height);
     os2->x_height = 0;
   }
   if (os2->cap_height < 0) {
     OTS_WARNING("bad cap_height: %d", os2->cap_height);
     os2->cap_height = 0;
   }
@@ skipping 17 matching lines @@
       !out->WriteS16(os2->subscript_y_size) ||
       !out->WriteS16(os2->subscript_x_offset) ||
       !out->WriteS16(os2->subscript_y_offset) ||
       !out->WriteS16(os2->superscript_x_size) ||
       !out->WriteS16(os2->superscript_y_size) ||
       !out->WriteS16(os2->superscript_x_offset) ||
       !out->WriteS16(os2->superscript_y_offset) ||
       !out->WriteS16(os2->strikeout_size) ||
       !out->WriteS16(os2->strikeout_position) ||
       !out->WriteS16(os2->family_class)) {
-    return OTS_FAILURE();
+    return OTS_FAILURE_MSG("Failed to write basic OS2 information");
   }
 
   for (unsigned i = 0; i < 10; ++i) {
     if (!out->Write(&os2->panose[i], 1)) {
-      return OTS_FAILURE();
+      return OTS_FAILURE_MSG("Failed to write os2 panose information");
     }
   }
 
   if (!out->WriteU32(os2->unicode_range_1) ||
       !out->WriteU32(os2->unicode_range_2) ||
       !out->WriteU32(os2->unicode_range_3) ||
       !out->WriteU32(os2->unicode_range_4) ||
       !out->WriteU32(os2->vendor_id) ||
       !out->WriteU16(os2->selection) ||
       !out->WriteU16(os2->first_char_index) ||
       !out->WriteU16(os2->last_char_index) ||
       !out->WriteS16(os2->typo_ascender) ||
       !out->WriteS16(os2->typo_descender) ||
       !out->WriteS16(os2->typo_linegap) ||
       !out->WriteU16(os2->win_ascent) ||
       !out->WriteU16(os2->win_descent)) {
-    return OTS_FAILURE();
+    return OTS_FAILURE_MSG("Failed to write os2 version 1 information");
   }
 
   if (os2->version < 1) {
     return true;
   }
 
   if (!out->WriteU32(os2->code_page_range_1) ||
       !out->WriteU32(os2->code_page_range_2)) {
-    return OTS_FAILURE();
+    return OTS_FAILURE_MSG("Failed to write codepage ranges");
   }
 
   if (os2->version < 2) {
     return true;
   }
 
   if (!out->WriteS16(os2->x_height) ||
       !out->WriteS16(os2->cap_height) ||
       !out->WriteU16(os2->default_char) ||
       !out->WriteU16(os2->break_char) ||
       !out->WriteU16(os2->max_context)) {
-    return OTS_FAILURE();
+    return OTS_FAILURE_MSG("Failed to write os2 version 2 information");
   }
 
   return true;
 }
 
 void ots_os2_free(OpenTypeFile *file) {
   delete file->os2;
 }
 
 }  // namespace ots
+
+#undef TABLE_NAME