Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 177 insertions, 0 deletions

diff --git a/gfx/ots/src/metrics.cc b/gfx/ots/src/metrics.cc
new file mode 100644
index 0000000000..3959d5d8da
--- /dev/null
+++ b/gfx/ots/src/metrics.cc
@@ -0,0 +1,177 @@
+// Copyright (c) 2011-2017 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.
+
+#include "metrics.h"
+
+#include "head.h"
+#include "maxp.h"
+
+// OpenType horizontal and vertical common header format
+// http://www.microsoft.com/typography/otspec/hhea.htm
+// http://www.microsoft.com/typography/otspec/vhea.htm
+
+namespace ots {
+
+bool OpenTypeMetricsHeader::Parse(const uint8_t *data, size_t length) {
+  Buffer table(data, length);
+
+  // Skip already read version.
+  if (!table.Skip(4)) {
+    return false;
+  }
+
+  if (!table.ReadS16(&this->ascent) ||
+      !table.ReadS16(&this->descent) ||
+      !table.ReadS16(&this->linegap) ||
+      !table.ReadU16(&this->adv_width_max) ||
+      !table.ReadS16(&this->min_sb1) ||
+      !table.ReadS16(&this->min_sb2) ||
+      !table.ReadS16(&this->max_extent) ||
+      !table.ReadS16(&this->caret_slope_rise) ||
+      !table.ReadS16(&this->caret_slope_run) ||
+      !table.ReadS16(&this->caret_offset)) {
+    return Error("Failed to read table");
+  }
+
+  if (this->ascent < 0) {
+    Warning("Negative ascent, setting to 0: %d", this->ascent);
+    this->ascent = 0;
+  }
+  if (this->linegap < 0) {
+    Warning("Negative linegap, setting to: %d", this->linegap);
+    this->linegap = 0;
+  }
+
+  OpenTypeHEAD *head = static_cast<OpenTypeHEAD*>(
+      GetFont()->GetTypedTable(OTS_TAG_HEAD));
+  if (!head) {
+    return Error("Missing head font table");
+  }
+
+  // if the font is non-slanted, caret_offset should be zero.
+  if (!(head->mac_style & 2) &&
+      (this->caret_offset != 0)) {
+    Warning("Non-zero caretOffset but head.macStyle italic bit is not set, setting to caretOffset to 0: %d", this->caret_offset);
+    this->caret_offset = 0;
+  }
+
+  // skip the reserved bytes
+  if (!table.Skip(8)) {
+    return Error("Failed to read reserved bytes");
+  }
+
+  int16_t data_format;
+  if (!table.ReadS16(&data_format)) {
+    return Error("Failed to read metricDataFormat");
+  }
+  if (data_format) {
+    return Error("Unsupported metricDataFormat: %d", data_format);
+  }
+
+  if (!table.ReadU16(&this->num_metrics)) {
+    return Error("Failed to read number of metrics");
+  }
+
+  OpenTypeMAXP *maxp = static_cast<OpenTypeMAXP*>(
+      GetFont()->GetTypedTable(OTS_TAG_MAXP));
+  if (!maxp) {
+    return Error("Missing maxp font table");
+  }
+
+  if (this->num_metrics > maxp->num_glyphs) {
+    return Error("Bad number of metrics %d", this->num_metrics);
+  }
+
+  return true;
+}
+
+bool OpenTypeMetricsHeader::Serialize(OTSStream *out) {
+  if (!out->WriteU32(this->version) ||
+      !out->WriteS16(this->ascent) ||
+      !out->WriteS16(this->descent) ||
+      !out->WriteS16(this->linegap) ||
+      !out->WriteU16(this->adv_width_max) ||
+      !out->WriteS16(this->min_sb1) ||
+      !out->WriteS16(this->min_sb2) ||
+      !out->WriteS16(this->max_extent) ||
+      !out->WriteS16(this->caret_slope_rise) ||
+      !out->WriteS16(this->caret_slope_run) ||
+      !out->WriteS16(this->caret_offset) ||
+      !out->WriteR64(0) ||  // reserved
+      !out->WriteS16(0) ||  // metric data format
+      !out->WriteU16(this->num_metrics)) {
+    return Error("Failed to write metrics");
+  }
+
+  return true;
+}
+
+bool OpenTypeMetricsTable::Parse(const uint8_t *data, size_t length) {
+  Buffer table(data, length);
+
+  // OpenTypeMetricsHeader is a superclass of both 'hhea' and 'vhea',
+  // so the cast here is OK, whichever m_header_tag we have.
+  OpenTypeMetricsHeader *header = static_cast<OpenTypeMetricsHeader*>(
+      GetFont()->GetTypedTable(m_header_tag));
+  if (!header) {
+    return Error("Required %c%c%c%c table missing", OTS_UNTAG(m_header_tag));
+  }
+  // |num_metrics| is a uint16_t, so it's bounded < 65536. This limits that
+  // amount of memory that we'll allocate for this to a sane amount.
+  const unsigned num_metrics = header->num_metrics;
+
+  OpenTypeMAXP *maxp = static_cast<OpenTypeMAXP*>(
+      GetFont()->GetTypedTable(OTS_TAG_MAXP));
+  if (!maxp) {
+    return Error("Required maxp table missing");
+  }
+  if (num_metrics > maxp->num_glyphs) {
+    return Error("Bad number of metrics %d", num_metrics);
+  }
+  if (!num_metrics) {
+    return Error("No metrics!");
+  }
+  const unsigned num_sbs = maxp->num_glyphs - num_metrics;
+
+  this->entries.reserve(num_metrics);
+  for (unsigned i = 0; i < num_metrics; ++i) {
+    uint16_t adv = 0;
+    int16_t sb = 0;
+    if (!table.ReadU16(&adv) || !table.ReadS16(&sb)) {
+      return Error("Failed to read metric %d", i);
+    }
+    this->entries.push_back(std::make_pair(adv, sb));
+  }
+
+  this->sbs.reserve(num_sbs);
+  for (unsigned i = 0; i < num_sbs; ++i) {
+    int16_t sb;
+    if (!table.ReadS16(&sb)) {
+      // Some Japanese fonts (e.g., mona.ttf) fail this test.
+      return Error("Failed to read side bearing %d", i + num_metrics);
+    }
+    this->sbs.push_back(sb);
+  }
+
+  return true;
+}
+
+bool OpenTypeMetricsTable::Serialize(OTSStream *out) {
+  for (unsigned i = 0; i < this->entries.size(); ++i) {
+    if (!out->WriteU16(this->entries[i].first) ||
+        !out->WriteS16(this->entries[i].second)) {
+      return Error("Failed to write metric %d", i);
+    }
+  }
+
+  for (unsigned i = 0; i < this->sbs.size(); ++i) {
+    if (!out->WriteS16(this->sbs[i])) {
+      return Error("Failed to write side bearing %ld", i + this->entries.size());
+    }
+  }
+
+  return true;
+}
+
+}  // namespace ots