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-rw-r--r--gfx/ots/src/glyf.cc328
1 files changed, 191 insertions, 137 deletions
diff --git a/gfx/ots/src/glyf.cc b/gfx/ots/src/glyf.cc
index 311916dc0..0c19d6d7b 100644
--- a/gfx/ots/src/glyf.cc
+++ b/gfx/ots/src/glyf.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Copyright (c) 2009-2017 The OTS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
@@ -14,20 +14,15 @@
// glyf - Glyph Data
// http://www.microsoft.com/typography/otspec/glyf.htm
-#define TABLE_NAME "glyf"
-
-namespace {
+namespace ots {
-bool ParseFlagsForSimpleGlyph(ots::Font *font,
- ots::Buffer *table,
- uint32_t gly_length,
- uint32_t num_flags,
- uint32_t *flags_count_logical,
- uint32_t *flags_count_physical,
- uint32_t *xy_coordinates_length) {
+bool OpenTypeGLYF::ParseFlagsForSimpleGlyph(Buffer &glyph,
+ uint32_t num_flags,
+ uint32_t *flag_index,
+ uint32_t *coordinates_length) {
uint8_t flag = 0;
- if (!table->ReadU8(&flag)) {
- return OTS_FAILURE_MSG("Can't read flag");
+ if (!glyph.ReadU8(&flag)) {
+ return Error("Can't read flag");
}
uint32_t delta = 0;
@@ -43,140 +38,205 @@ bool ParseFlagsForSimpleGlyph(ots::Font *font,
delta += 2;
}
+ /* MS and Apple specs say this bit is reserved and must be set to zero, but
+ * Apple spec then contradicts itself and says it should be set on the first
+ * contour flag for simple glyphs with overlapping contours:
+ * https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6AATIntro.html
+ * (“Overlapping contours” section) */
+ if (flag & (1u << 6) && *flag_index != 0) {
+ return Error("Bad glyph flag (%d), "
+ "bit 6 must be set to zero for flag %d", flag, *flag_index);
+ }
+
if (flag & (1u << 3)) { // repeat
- if (*flags_count_logical + 1 >= num_flags) {
- return OTS_FAILURE_MSG("Count too high (%d + 1 >= %d)", *flags_count_logical, num_flags);
+ if (*flag_index + 1 >= num_flags) {
+ return Error("Count too high (%d + 1 >= %d)", *flag_index, num_flags);
}
uint8_t repeat = 0;
- if (!table->ReadU8(&repeat)) {
- return OTS_FAILURE_MSG("Can't read repeat value");
+ if (!glyph.ReadU8(&repeat)) {
+ return Error("Can't read repeat value");
}
if (repeat == 0) {
- return OTS_FAILURE_MSG("Zero repeat");
+ return Error("Zero repeat");
}
delta += (delta * repeat);
- *flags_count_logical += repeat;
- if (*flags_count_logical >= num_flags) {
- return OTS_FAILURE_MSG("Count too high (%d >= %d)", *flags_count_logical, num_flags);
+ *flag_index += repeat;
+ if (*flag_index >= num_flags) {
+ return Error("Count too high (%d >= %d)", *flag_index, num_flags);
}
- ++(*flags_count_physical);
}
- if ((flag & (1u << 6)) || (flag & (1u << 7))) { // reserved flags
- return OTS_FAILURE_MSG("Bad glyph flag value (%d), reserved flags must be set to zero", flag);
+ if (flag & (1u << 7)) { // reserved flag
+ return Error("Bad glyph flag (%d), reserved bit 7 must be set to zero", flag);
}
- *xy_coordinates_length += delta;
- if (gly_length < *xy_coordinates_length) {
- return OTS_FAILURE_MSG("Glyph coordinates length too low (%d < %d)", gly_length, *xy_coordinates_length);
+ *coordinates_length += delta;
+ if (glyph.length() < *coordinates_length) {
+ return Error("Glyph coordinates length bigger than glyph length (%d > %d)",
+ *coordinates_length, glyph.length());
}
return true;
}
-bool ParseSimpleGlyph(ots::Font *font, const uint8_t *data,
- ots::Buffer *table, int16_t num_contours,
- uint32_t gly_offset, uint32_t gly_length,
- uint32_t *new_size) {
- ots::OpenTypeGLYF *glyf = font->glyf;
-
+bool OpenTypeGLYF::ParseSimpleGlyph(Buffer &glyph,
+ int16_t num_contours) {
// read the end-points array
uint16_t num_flags = 0;
for (int i = 0; i < num_contours; ++i) {
uint16_t tmp_index = 0;
- if (!table->ReadU16(&tmp_index)) {
- return OTS_FAILURE_MSG("Can't read contour index %d", i);
+ if (!glyph.ReadU16(&tmp_index)) {
+ return Error("Can't read contour index %d", i);
}
if (tmp_index == 0xffffu) {
- return OTS_FAILURE_MSG("Bad contour index %d", i);
+ return Error("Bad contour index %d", i);
}
// check if the indices are monotonically increasing
if (i && (tmp_index + 1 <= num_flags)) {
- return OTS_FAILURE_MSG("Decreasing contour index %d + 1 <= %d", tmp_index, num_flags);
+ return Error("Decreasing contour index %d + 1 <= %d", tmp_index, num_flags);
}
num_flags = tmp_index + 1;
}
uint16_t bytecode_length = 0;
- if (!table->ReadU16(&bytecode_length)) {
- return OTS_FAILURE_MSG("Can't read bytecode length");
- }
- if ((font->maxp->version_1) &&
- (font->maxp->max_size_glyf_instructions < bytecode_length)) {
- return OTS_FAILURE_MSG("Bytecode length too high %d", bytecode_length);
+ if (!glyph.ReadU16(&bytecode_length)) {
+ return Error("Can't read bytecode length");
}
- const uint32_t gly_header_length = 10 + num_contours * 2 + 2;
- if (gly_length < (gly_header_length + bytecode_length)) {
- return OTS_FAILURE_MSG("Glyph header length too high %d", gly_header_length);
+ if (this->maxp->version_1 &&
+ this->maxp->max_size_glyf_instructions < bytecode_length) {
+ this->maxp->max_size_glyf_instructions = bytecode_length;
+ Warning("Bytecode length is bigger than maxp.maxSizeOfInstructions %d: %d",
+ this->maxp->max_size_glyf_instructions, bytecode_length);
}
- glyf->iov.push_back(std::make_pair(
- data + gly_offset,
- static_cast<size_t>(gly_header_length + bytecode_length)));
-
- if (!table->Skip(bytecode_length)) {
- return OTS_FAILURE_MSG("Can't skip bytecode of length %d", bytecode_length);
+ if (!glyph.Skip(bytecode_length)) {
+ return Error("Can't read bytecode of length %d", bytecode_length);
}
- uint32_t flags_count_physical = 0; // on memory
- uint32_t xy_coordinates_length = 0;
- for (uint32_t flags_count_logical = 0;
- flags_count_logical < num_flags;
- ++flags_count_logical, ++flags_count_physical) {
- if (!ParseFlagsForSimpleGlyph(font,
- table,
- gly_length,
- num_flags,
- &flags_count_logical,
- &flags_count_physical,
- &xy_coordinates_length)) {
- return OTS_FAILURE_MSG("Failed to parse glyph flags %d", flags_count_logical);
+ uint32_t coordinates_length = 0;
+ for (uint32_t i = 0; i < num_flags; ++i) {
+ if (!ParseFlagsForSimpleGlyph(glyph, num_flags, &i, &coordinates_length)) {
+ return Error("Failed to parse glyph flags %d", i);
}
}
- if (gly_length < (gly_header_length + bytecode_length +
- flags_count_physical + xy_coordinates_length)) {
- return OTS_FAILURE_MSG("Glyph too short %d", gly_length);
+ if (!glyph.Skip(coordinates_length)) {
+ return Error("Glyph too short %d", glyph.length());
}
- if (gly_length - (gly_header_length + bytecode_length +
- flags_count_physical + xy_coordinates_length) > 3) {
+ if (glyph.remaining() > 3) {
// We allow 0-3 bytes difference since gly_length is 4-bytes aligned,
// zero-padded length.
- return OTS_FAILURE_MSG("Invalid glyph length %d", gly_length);
+ Warning("Extra bytes at end of the glyph: %d", glyph.remaining());
}
- glyf->iov.push_back(std::make_pair(
- data + gly_offset + gly_header_length + bytecode_length,
- static_cast<size_t>(flags_count_physical + xy_coordinates_length)));
-
- *new_size
- = gly_header_length + flags_count_physical + xy_coordinates_length + bytecode_length;
+ this->iov.push_back(std::make_pair(glyph.buffer(), glyph.offset()));
return true;
}
-} // namespace
+#define ARG_1_AND_2_ARE_WORDS (1u << 0)
+#define WE_HAVE_A_SCALE (1u << 3)
+#define MORE_COMPONENTS (1u << 5)
+#define WE_HAVE_AN_X_AND_Y_SCALE (1u << 6)
+#define WE_HAVE_A_TWO_BY_TWO (1u << 7)
+#define WE_HAVE_INSTRUCTIONS (1u << 8)
+
+bool OpenTypeGLYF::ParseCompositeGlyph(Buffer &glyph) {
+ uint16_t flags = 0;
+ uint16_t gid = 0;
+ do {
+ if (!glyph.ReadU16(&flags) || !glyph.ReadU16(&gid)) {
+ return Error("Can't read composite glyph flags or glyphIndex");
+ }
-namespace ots {
+ if (gid >= this->maxp->num_glyphs) {
+ return Error("Invalid glyph id used in composite glyph: %d", gid);
+ }
+
+ if (flags & ARG_1_AND_2_ARE_WORDS) {
+ int16_t argument1;
+ int16_t argument2;
+ if (!glyph.ReadS16(&argument1) || !glyph.ReadS16(&argument2)) {
+ return Error("Can't read argument1 or argument2");
+ }
+ } else {
+ uint8_t argument1;
+ uint8_t argument2;
+ if (!glyph.ReadU8(&argument1) || !glyph.ReadU8(&argument2)) {
+ return Error("Can't read argument1 or argument2");
+ }
+ }
+
+ if (flags & WE_HAVE_A_SCALE) {
+ int16_t scale;
+ if (!glyph.ReadS16(&scale)) {
+ return Error("Can't read scale");
+ }
+ } else if (flags & WE_HAVE_AN_X_AND_Y_SCALE) {
+ int16_t xscale;
+ int16_t yscale;
+ if (!glyph.ReadS16(&xscale) || !glyph.ReadS16(&yscale)) {
+ return Error("Can't read xscale or yscale");
+ }
+ } else if (flags & WE_HAVE_A_TWO_BY_TWO) {
+ int16_t xscale;
+ int16_t scale01;
+ int16_t scale10;
+ int16_t yscale;
+ if (!glyph.ReadS16(&xscale) ||
+ !glyph.ReadS16(&scale01) ||
+ !glyph.ReadS16(&scale10) ||
+ !glyph.ReadS16(&yscale)) {
+ return Error("Can't read transform");
+ }
+ }
+ } while (flags & MORE_COMPONENTS);
+
+ if (flags & WE_HAVE_INSTRUCTIONS) {
+ uint16_t bytecode_length;
+ if (!glyph.ReadU16(&bytecode_length)) {
+ return Error("Can't read instructions size");
+ }
-bool ots_glyf_parse(Font *font, const uint8_t *data, size_t length) {
- Buffer table(data, length);
+ if (this->maxp->version_1 &&
+ this->maxp->max_size_glyf_instructions < bytecode_length) {
+ this->maxp->max_size_glyf_instructions = bytecode_length;
+ Warning("Bytecode length is bigger than maxp.maxSizeOfInstructions "
+ "%d: %d",
+ this->maxp->max_size_glyf_instructions, bytecode_length);
+ }
- if (!font->maxp || !font->loca || !font->head) {
- return OTS_FAILURE_MSG("Missing maxp or loca or head table needed by glyf table");
+ if (!glyph.Skip(bytecode_length)) {
+ return Error("Can't read bytecode of length %d", bytecode_length);
+ }
}
- OpenTypeGLYF *glyf = new OpenTypeGLYF;
- font->glyf = glyf;
+ this->iov.push_back(std::make_pair(glyph.buffer(), glyph.offset()));
- const unsigned num_glyphs = font->maxp->num_glyphs;
- std::vector<uint32_t> &offsets = font->loca->offsets;
+ return true;
+}
+
+bool OpenTypeGLYF::Parse(const uint8_t *data, size_t length) {
+ OpenTypeMAXP *maxp = static_cast<OpenTypeMAXP*>(
+ GetFont()->GetTypedTable(OTS_TAG_MAXP));
+ OpenTypeLOCA *loca = static_cast<OpenTypeLOCA*>(
+ GetFont()->GetTypedTable(OTS_TAG_LOCA));
+ OpenTypeHEAD *head = static_cast<OpenTypeHEAD*>(
+ GetFont()->GetTypedTable(OTS_TAG_HEAD));
+ if (!maxp || !loca || !head) {
+ return Error("Missing maxp or loca or head table needed by glyf table");
+ }
+
+ this->maxp = maxp;
+
+ const unsigned num_glyphs = maxp->num_glyphs;
+ std::vector<uint32_t> &offsets = loca->offsets;
if (offsets.size() != num_glyphs + 1) {
- return OTS_FAILURE_MSG("Invalide glyph offsets size %ld != %d", offsets.size(), num_glyphs + 1);
+ return Error("Invalide glyph offsets size %ld != %d", offsets.size(), num_glyphs + 1);
}
std::vector<uint32_t> resulting_offsets(num_glyphs + 1);
@@ -193,30 +253,31 @@ bool ots_glyf_parse(Font *font, const uint8_t *data, size_t length) {
}
if (gly_offset >= length) {
- return OTS_FAILURE_MSG("Glyph %d offset %d too high %ld", i, gly_offset, length);
+ return Error("Glyph %d offset %d too high %ld", i, gly_offset, length);
}
// Since these are unsigned types, the compiler is not allowed to assume
// that they never overflow.
if (gly_offset + gly_length < gly_offset) {
- return OTS_FAILURE_MSG("Glyph %d length (%d < 0)!", i, gly_length);
+ return Error("Glyph %d length (%d < 0)!", i, gly_length);
}
if (gly_offset + gly_length > length) {
- return OTS_FAILURE_MSG("Glyph %d length %d too high", i, gly_length);
+ return Error("Glyph %d length %d too high", i, gly_length);
}
- table.set_offset(gly_offset);
+ Buffer glyph(data + gly_offset, gly_length);
+
int16_t num_contours, xmin, ymin, xmax, ymax;
- if (!table.ReadS16(&num_contours) ||
- !table.ReadS16(&xmin) ||
- !table.ReadS16(&ymin) ||
- !table.ReadS16(&xmax) ||
- !table.ReadS16(&ymax)) {
- return OTS_FAILURE_MSG("Can't read glyph %d header", i);
+ if (!glyph.ReadS16(&num_contours) ||
+ !glyph.ReadS16(&xmin) ||
+ !glyph.ReadS16(&ymin) ||
+ !glyph.ReadS16(&xmax) ||
+ !glyph.ReadS16(&ymax)) {
+ return Error("Can't read glyph %d header", i);
}
if (num_contours <= -2) {
// -2, -3, -4, ... are reserved for future use.
- return OTS_FAILURE_MSG("Bad number of contours %d in glyph %d", num_contours, i);
+ return Error("Bad number of contours %d in glyph %d", num_contours, i);
}
// workaround for fonts in http://www.princexml.com/fonts/
@@ -224,35 +285,36 @@ bool ots_glyf_parse(Font *font, const uint8_t *data, size_t length) {
(xmax == -32767) &&
(ymin == 32767) &&
(ymax == -32767)) {
- OTS_WARNING("bad xmin/xmax/ymin/ymax values");
+ Warning("bad xmin/xmax/ymin/ymax values");
xmin = xmax = ymin = ymax = 0;
}
if (xmin > xmax || ymin > ymax) {
- return OTS_FAILURE_MSG("Bad bounding box values bl=(%d, %d), tr=(%d, %d) in glyph %d", xmin, ymin, xmax, ymax, i);
+ return Error("Bad bounding box values bl=(%d, %d), tr=(%d, %d) in glyph %d", xmin, ymin, xmax, ymax, i);
}
- unsigned new_size = 0;
- if (num_contours >= 0) {
- // this is a simple glyph and might contain bytecode
- if (!ParseSimpleGlyph(font, data, &table,
- num_contours, gly_offset, gly_length, &new_size)) {
- return OTS_FAILURE_MSG("Failed to parse glyph %d", i);
+ if (num_contours == 0) {
+ // This is an empty glyph and shouldn’t have any glyph data, but if it
+ // does we will simply ignore it.
+ glyph.set_offset(0);
+ } else if (num_contours > 0) {
+ if (!ParseSimpleGlyph(glyph, num_contours)) {
+ return Error("Failed to parse glyph %d", i);
}
} else {
- // it's a composite glyph without any bytecode. Enqueue the whole thing
- glyf->iov.push_back(std::make_pair(data + gly_offset,
- static_cast<size_t>(gly_length)));
- new_size = gly_length;
+ if (!ParseCompositeGlyph(glyph)) {
+ return Error("Failed to parse glyph %d", i);
+ }
}
+ size_t new_size = glyph.offset();
resulting_offsets[i] = current_offset;
// glyphs must be four byte aligned
// TODO(yusukes): investigate whether this padding is really necessary.
// Which part of the spec requires this?
const unsigned padding = (4 - (new_size & 3)) % 4;
if (padding) {
- glyf->iov.push_back(std::make_pair(
+ this->iov.push_back(std::make_pair(
reinterpret_cast<const uint8_t*>("\x00\x00\x00\x00"),
static_cast<size_t>(padding)));
new_size += padding;
@@ -264,40 +326,32 @@ bool ots_glyf_parse(Font *font, const uint8_t *data, size_t length) {
const uint16_t max16 = std::numeric_limits<uint16_t>::max();
if ((*std::max_element(resulting_offsets.begin(),
resulting_offsets.end()) >= (max16 * 2u)) &&
- (font->head->index_to_loc_format != 1)) {
- OTS_WARNING("2-bytes indexing is not possible (due to the padding above)");
- font->head->index_to_loc_format = 1;
+ (head->index_to_loc_format != 1)) {
+ head->index_to_loc_format = 1;
}
- font->loca->offsets = resulting_offsets;
- return true;
-}
-
-bool ots_glyf_should_serialise(Font *font) {
- return font->glyf != NULL;
-}
-
-bool ots_glyf_serialise(OTSStream *out, Font *font) {
- const OpenTypeGLYF *glyf = font->glyf;
+ loca->offsets = resulting_offsets;
- for (unsigned i = 0; i < glyf->iov.size(); ++i) {
- if (!out->Write(glyf->iov[i].first, glyf->iov[i].second)) {
- return OTS_FAILURE_MSG("Falied to write glyph %d", i);
- }
+ if (this->iov.empty()) {
+ // As a special case when all glyph in the font are empty, add a zero byte
+ // to the table, so that we don’t reject it down the way, and to make the
+ // table work on Windows as well.
+ // See https://github.com/khaledhosny/ots/issues/52
+ static const uint8_t kZero = 0;
+ this->iov.push_back(std::make_pair(&kZero, 1));
}
return true;
}
-void ots_glyf_reuse(Font *font, Font *other) {
- font->glyf = other->glyf;
- font->glyf_reused = true;
-}
+bool OpenTypeGLYF::Serialize(OTSStream *out) {
+ for (unsigned i = 0; i < this->iov.size(); ++i) {
+ if (!out->Write(this->iov[i].first, this->iov[i].second)) {
+ return Error("Falied to write glyph %d", i);
+ }
+ }
-void ots_glyf_free(Font *font) {
- delete font->glyf;
+ return true;
}
} // namespace ots
-
-#undef TABLE_NAME
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-23 14:18:39 +0000