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-rw-r--r--gfx/ots/src/post.cc193
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diff --git a/gfx/ots/src/post.cc b/gfx/ots/src/post.cc
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+++ b/gfx/ots/src/post.cc
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+// 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 "post.h"
+
+#include "maxp.h"
+
+// post - PostScript
+// http://www.microsoft.com/typography/otspec/post.htm
+
+#define TABLE_NAME "post"
+
+namespace ots {
+
+bool ots_post_parse(Font *font, const uint8_t *data, size_t length) {
+ Buffer table(data, length);
+
+ OpenTypePOST *post = new OpenTypePOST;
+ font->post = post;
+
+ if (!table.ReadU32(&post->version) ||
+ !table.ReadU32(&post->italic_angle) ||
+ !table.ReadS16(&post->underline) ||
+ !table.ReadS16(&post->underline_thickness) ||
+ !table.ReadU32(&post->is_fixed_pitch)) {
+ return OTS_FAILURE_MSG("Failed to read post header");
+ }
+
+ if (post->underline_thickness < 0) {
+ post->underline_thickness = 1;
+ }
+
+ if (post->version == 0x00010000) {
+ return true;
+ } else if (post->version == 0x00030000) {
+ return true;
+ } else if (post->version != 0x00020000) {
+ // 0x00025000 is deprecated. We don't accept it.
+ return OTS_FAILURE_MSG("Bad post version %x", post->version);
+ }
+
+ // We have a version 2 table with a list of Pascal strings at the end
+
+ // We don't care about the memory usage fields. We'll set all these to zero
+ // when serialising
+ if (!table.Skip(16)) {
+ return OTS_FAILURE_MSG("Failed to skip memory usage in post table");
+ }
+
+ uint16_t num_glyphs = 0;
+ if (!table.ReadU16(&num_glyphs)) {
+ return OTS_FAILURE_MSG("Failed to read number of glyphs");
+ }
+
+ if (!font->maxp) {
+ return OTS_FAILURE_MSG("No maxp table required by post table");
+ }
+
+ if (num_glyphs == 0) {
+ if (font->maxp->num_glyphs > 258) {
+ return OTS_FAILURE_MSG("Can't have no glyphs in the post table if there are more than 256 glyphs in the font");
+ }
+ OTS_WARNING("table version is 1, but no glyf names are found");
+ // workaround for fonts in http://www.fontsquirrel.com/fontface
+ // (e.g., yataghan.ttf).
+ post->version = 0x00010000;
+ return true;
+ }
+
+ if (num_glyphs != font->maxp->num_glyphs) {
+ // Note: Fixedsys500c.ttf seems to have inconsistent num_glyphs values.
+ return OTS_FAILURE_MSG("Bad number of glyphs in post table %d", num_glyphs);
+ }
+
+ post->glyph_name_index.resize(num_glyphs);
+ for (unsigned i = 0; i < num_glyphs; ++i) {
+ if (!table.ReadU16(&post->glyph_name_index[i])) {
+ return OTS_FAILURE_MSG("Failed to read post information for glyph %d", i);
+ }
+ // Note: A strict interpretation of the specification requires name indexes
+ // are less than 32768. This, however, excludes fonts like unifont.ttf
+ // which cover all of unicode.
+ }
+
+ // Now we have an array of Pascal strings. We have to check that they are all
+ // valid and read them in.
+ const size_t strings_offset = table.offset();
+ const uint8_t *strings = data + strings_offset;
+ const uint8_t *strings_end = data + length;
+
+ for (;;) {
+ if (strings == strings_end) break;
+ const unsigned string_length = *strings;
+ if (strings + 1 + string_length > strings_end) {
+ return OTS_FAILURE_MSG("Bad string length %d", string_length);
+ }
+ if (std::memchr(strings + 1, '\0', string_length)) {
+ return OTS_FAILURE_MSG("Bad string of length %d", string_length);
+ }
+ post->names.push_back(
+ std::string(reinterpret_cast<const char*>(strings + 1), string_length));
+ strings += 1 + string_length;
+ }
+ const unsigned num_strings = post->names.size();
+
+ // check that all the references are within bounds
+ for (unsigned i = 0; i < num_glyphs; ++i) {
+ unsigned offset = post->glyph_name_index[i];
+ if (offset < 258) {
+ continue;
+ }
+
+ offset -= 258;
+ if (offset >= num_strings) {
+ return OTS_FAILURE_MSG("Bad string index %d", offset);
+ }
+ }
+
+ return true;
+}
+
+bool ots_post_should_serialise(Font *font) {
+ return font->post != NULL;
+}
+
+bool ots_post_serialise(OTSStream *out, Font *font) {
+ const OpenTypePOST *post = font->post;
+
+ // OpenType with CFF glyphs must have v3 post table.
+ if (post && font->cff && post->version != 0x00030000) {
+ return OTS_FAILURE_MSG("Bad post version %x", post->version);
+ }
+
+ if (!out->WriteU32(post->version) ||
+ !out->WriteU32(post->italic_angle) ||
+ !out->WriteS16(post->underline) ||
+ !out->WriteS16(post->underline_thickness) ||
+ !out->WriteU32(post->is_fixed_pitch) ||
+ !out->WriteU32(0) ||
+ !out->WriteU32(0) ||
+ !out->WriteU32(0) ||
+ !out->WriteU32(0)) {
+ return OTS_FAILURE_MSG("Failed to write post header");
+ }
+
+ if (post->version != 0x00020000) {
+ return true; // v1.0 and v3.0 does not have glyph names.
+ }
+
+ const uint16_t num_indexes =
+ static_cast<uint16_t>(post->glyph_name_index.size());
+ if (num_indexes != post->glyph_name_index.size() ||
+ !out->WriteU16(num_indexes)) {
+ return OTS_FAILURE_MSG("Failed to write number of indices");
+ }
+
+ for (uint16_t i = 0; i < num_indexes; ++i) {
+ if (!out->WriteU16(post->glyph_name_index[i])) {
+ return OTS_FAILURE_MSG("Failed to write name index %d", i);
+ }
+ }
+
+ // Now we just have to write out the strings in the correct order
+ for (unsigned i = 0; i < post->names.size(); ++i) {
+ const std::string& s = post->names[i];
+ const uint8_t string_length = static_cast<uint8_t>(s.size());
+ if (string_length != s.size() ||
+ !out->Write(&string_length, 1)) {
+ return OTS_FAILURE_MSG("Failed to write string %d", i);
+ }
+ // Some ttf fonts (e.g., frank.ttf on Windows Vista) have zero-length name.
+ // We allow them.
+ if (string_length > 0 && !out->Write(s.data(), string_length)) {
+ return OTS_FAILURE_MSG("Failed to write string length for string %d", i);
+ }
+ }
+
+ return true;
+}
+
+void ots_post_reuse(Font *font, Font *other) {
+ font->post = other->post;
+ font->post_reused = true;
+}
+
+void ots_post_free(Font *font) {
+ delete font->post;
+}
+
+} // namespace ots
+
+#undef TABLE_NAME