Fix MSVC warnings about possible value truncation.

src/cmap.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 "cmap.h"
 
 #include <algorithm>
 #include <set>
 #include <utility>
 #include <vector>
@@ skipping 196 matching lines @@
   // The last range must end at 0xffff
   if (ranges[segcount - 1].end_range != 0xffff) {
     return OTS_FAILURE();
   }
 
   // A format 4 CMAP subtable is complex. To be safe we simulate a lookup of
   // each code-point defined in the table and make sure that they are all valid
   // glyphs and that we don't access anything out-of-bounds.
   for (unsigned i = 0; i < segcount; ++i) {
     for (unsigned cp = ranges[i].start_range; cp <= ranges[i].end_range; ++cp) {
-      const uint16_t code_point = cp;
+      const uint16_t code_point = static_cast<uint16_t>(cp);
       if (ranges[i].id_range_offset == 0) {
         // this is explictly allowed to overflow in the spec
         const uint16_t glyph = code_point + ranges[i].id_delta;
         if (glyph >= num_glyphs) {
           return OTS_FAILURE();
         }
       } else {
         const uint16_t range_delta = code_point - ranges[i].start_range;
         // this might seem odd, but it's true. The offset is relative to the
         // location of the offset value itself.
@@ skipping 603 matching lines @@
 bool ots_cmap_serialise(OTSStream *out, OpenTypeFile *file) {
   const bool have_034 = file->cmap->subtable_0_3_4_data != NULL;
   const bool have_0514 = file->cmap->subtable_0_5_14.size() != 0;
   const bool have_100 = file->cmap->subtable_1_0_0.size() != 0;
   const bool have_304 = file->cmap->subtable_3_0_4_data != NULL;
   // MS Symbol and MS Unicode tables should not co-exist.
   // See the comment above in 0-0-4 parser.
   const bool have_314 = (!have_304) && file->cmap->subtable_3_1_4_data;
   const bool have_31012 = file->cmap->subtable_3_10_12.size() != 0;
   const bool have_31013 = file->cmap->subtable_3_10_13.size() != 0;
-  const unsigned num_subtables = static_cast<unsigned>(have_034) +
-                                 static_cast<unsigned>(have_0514) +
-                                 static_cast<unsigned>(have_100) +
-                                 static_cast<unsigned>(have_304) +
-                                 static_cast<unsigned>(have_314) +
-                                 static_cast<unsigned>(have_31012) +
-                                 static_cast<unsigned>(have_31013);
+  const uint16_t num_subtables = static_cast<uint16_t>(have_034) +
+                                 static_cast<uint16_t>(have_0514) +
+                                 static_cast<uint16_t>(have_100) +
+                                 static_cast<uint16_t>(have_304) +
+                                 static_cast<uint16_t>(have_314) +
+                                 static_cast<uint16_t>(have_31012) +
+                                 static_cast<uint16_t>(have_31013);
   const off_t table_start = out->Tell();
 
   // Some fonts don't have 3-0-4 MS Symbol nor 3-1-4 Unicode BMP tables
   // (e.g., old fonts for Mac). We don't support them except for color bitmap
   // fonts.
   if (!have_304 && !have_314 && !have_034) {
     if (!(file->cbdt && file->cblc)) {
       return OTS_FAILURE();
     }
   }
@@ skipping 212 matching lines @@
   out->RestoreChecksum(saved_checksum);
 
   return true;
 }
 
 void ots_cmap_free(OpenTypeFile *file) {
   delete file->cmap;
 }
 
 }  // namespace ots