yusukes@chromium.org | d257d18 | 2009-11-04 04:56:32 +0000 | [diff] [blame] | 1 | // Copyright (c) 2009 The Chromium Authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #include "post.h" |
| 6 | |
| 7 | #include "maxp.h" |
| 8 | |
| 9 | // post - PostScript |
| 10 | // http://www.microsoft.com/opentype/otspec/post.htm |
| 11 | |
| 12 | namespace ots { |
| 13 | |
| 14 | bool ots_post_parse(OpenTypeFile *file, const uint8_t *data, size_t length) { |
| 15 | Buffer table(data, length); |
| 16 | |
| 17 | OpenTypePOST *post = new OpenTypePOST; |
| 18 | file->post = post; |
| 19 | |
| 20 | if (!table.ReadU32(&post->version) || |
| 21 | !table.ReadU32(&post->italic_angle) || |
| 22 | !table.ReadS16(&post->underline) || |
| 23 | !table.ReadS16(&post->underline_thickness) || |
| 24 | !table.ReadU32(&post->is_fixed_pitch)) { |
| 25 | return OTS_FAILURE(); |
| 26 | } |
| 27 | |
| 28 | if (post->underline_thickness < 0) { |
| 29 | post->underline_thickness = 1; |
| 30 | } |
| 31 | |
| 32 | if (post->version == 0x00010000) { |
| 33 | return true; |
| 34 | } else if (post->version == 0x00030000) { |
| 35 | return true; |
| 36 | } else if (post->version != 0x00020000) { |
| 37 | // 0x00025000 is deprecated. We don't accept it. |
| 38 | return OTS_FAILURE(); |
| 39 | } |
| 40 | |
| 41 | // We have a version 2 table with a list of Pascal strings at the end |
| 42 | |
| 43 | // We don't care about the memory usage fields. We'll set all these to zero |
| 44 | // when serialising |
| 45 | if (!table.Skip(16)) { |
| 46 | return OTS_FAILURE(); |
| 47 | } |
| 48 | |
yusukes@chromium.org | 8ad0a17 | 2009-11-04 06:07:58 +0000 | [diff] [blame] | 49 | uint16_t num_glyphs = 0; |
yusukes@chromium.org | d257d18 | 2009-11-04 04:56:32 +0000 | [diff] [blame] | 50 | if (!table.ReadU16(&num_glyphs)) { |
| 51 | return OTS_FAILURE(); |
| 52 | } |
| 53 | |
| 54 | if (!file->maxp) { |
| 55 | return OTS_FAILURE(); |
| 56 | } |
| 57 | |
| 58 | if (num_glyphs == 0) { |
| 59 | if (file->maxp->num_glyphs > 258) { |
| 60 | return OTS_FAILURE(); |
| 61 | } |
| 62 | OTS_WARNING("table version is 1, but no glyf names are found"); |
| 63 | // workaround for fonts in http://www.fontsquirrel.com/fontface |
| 64 | // (e.g., yataghan.ttf). |
| 65 | post->version = 0x00010000; |
| 66 | return true; |
| 67 | } |
| 68 | |
| 69 | if (num_glyphs != file->maxp->num_glyphs) { |
| 70 | // Note: Fixedsys500c.ttf seems to have inconsistent num_glyphs values. |
| 71 | return OTS_FAILURE(); |
| 72 | } |
| 73 | |
| 74 | post->glyph_name_index.resize(num_glyphs); |
| 75 | for (unsigned i = 0; i < num_glyphs; ++i) { |
| 76 | if (!table.ReadU16(&post->glyph_name_index[i])) { |
| 77 | return OTS_FAILURE(); |
| 78 | } |
ksakamoto@chromium.org | e3e106e | 2013-11-19 07:21:22 +0000 | [diff] [blame] | 79 | // Note: A strict interpretation of the specification requires name indexes |
| 80 | // are less than 32768. This, however, excludes fonts like unifont.ttf |
| 81 | // which cover all of unicode. |
yusukes@chromium.org | d257d18 | 2009-11-04 04:56:32 +0000 | [diff] [blame] | 82 | } |
| 83 | |
| 84 | // Now we have an array of Pascal strings. We have to check that they are all |
| 85 | // valid and read them in. |
| 86 | const size_t strings_offset = table.offset(); |
| 87 | const uint8_t *strings = data + strings_offset; |
| 88 | const uint8_t *strings_end = data + length; |
| 89 | |
| 90 | for (;;) { |
| 91 | if (strings == strings_end) break; |
| 92 | const unsigned string_length = *strings; |
| 93 | if (strings + 1 + string_length > strings_end) { |
| 94 | return OTS_FAILURE(); |
| 95 | } |
| 96 | if (std::memchr(strings + 1, '\0', string_length)) { |
| 97 | return OTS_FAILURE(); |
| 98 | } |
| 99 | post->names.push_back( |
| 100 | std::string(reinterpret_cast<const char*>(strings + 1), string_length)); |
| 101 | strings += 1 + string_length; |
| 102 | } |
| 103 | const unsigned num_strings = post->names.size(); |
| 104 | |
| 105 | // check that all the references are within bounds |
| 106 | for (unsigned i = 0; i < num_glyphs; ++i) { |
| 107 | unsigned offset = post->glyph_name_index[i]; |
| 108 | if (offset < 258) { |
| 109 | continue; |
| 110 | } |
| 111 | |
| 112 | offset -= 258; |
| 113 | if (offset >= num_strings) { |
| 114 | return OTS_FAILURE(); |
| 115 | } |
| 116 | } |
| 117 | |
| 118 | return true; |
| 119 | } |
| 120 | |
| 121 | bool ots_post_should_serialise(OpenTypeFile *file) { |
agl@chromium.org | 2beaf1d | 2011-01-21 17:19:34 +0000 | [diff] [blame] | 122 | return file->post != NULL; |
yusukes@chromium.org | d257d18 | 2009-11-04 04:56:32 +0000 | [diff] [blame] | 123 | } |
| 124 | |
| 125 | bool ots_post_serialise(OTSStream *out, OpenTypeFile *file) { |
| 126 | const OpenTypePOST *post = file->post; |
| 127 | |
| 128 | // OpenType with CFF glyphs must have v3 post table. |
| 129 | if (file->post && file->cff && file->post->version != 0x00030000) { |
| 130 | return OTS_FAILURE(); |
| 131 | } |
| 132 | |
| 133 | if (!out->WriteU32(post->version) || |
| 134 | !out->WriteU32(post->italic_angle) || |
| 135 | !out->WriteS16(post->underline) || |
| 136 | !out->WriteS16(post->underline_thickness) || |
| 137 | !out->WriteU32(post->is_fixed_pitch) || |
| 138 | !out->WriteU32(0) || |
| 139 | !out->WriteU32(0) || |
| 140 | !out->WriteU32(0) || |
| 141 | !out->WriteU32(0)) { |
| 142 | return OTS_FAILURE(); |
| 143 | } |
| 144 | |
| 145 | if (post->version != 0x00020000) { |
| 146 | return true; // v1.0 and v3.0 does not have glyph names. |
| 147 | } |
| 148 | |
| 149 | if (!out->WriteU16(post->glyph_name_index.size())) { |
| 150 | return OTS_FAILURE(); |
| 151 | } |
| 152 | |
| 153 | for (unsigned i = 0; i < post->glyph_name_index.size(); ++i) { |
| 154 | if (!out->WriteU16(post->glyph_name_index[i])) { |
| 155 | return OTS_FAILURE(); |
| 156 | } |
| 157 | } |
| 158 | |
| 159 | // Now we just have to write out the strings in the correct order |
| 160 | for (unsigned i = 0; i < post->names.size(); ++i) { |
| 161 | const std::string& s = post->names[i]; |
| 162 | const uint8_t string_length = s.size(); |
| 163 | if (!out->Write(&string_length, 1)) { |
| 164 | return OTS_FAILURE(); |
| 165 | } |
| 166 | // Some ttf fonts (e.g., frank.ttf on Windows Vista) have zero-length name. |
| 167 | // We allow them. |
| 168 | if (string_length > 0 && !out->Write(s.data(), string_length)) { |
| 169 | return OTS_FAILURE(); |
| 170 | } |
| 171 | } |
| 172 | |
| 173 | return true; |
| 174 | } |
| 175 | |
| 176 | void ots_post_free(OpenTypeFile *file) { |
| 177 | delete file->post; |
| 178 | } |
| 179 | |
| 180 | } // namespace ots |