[prelim] Additional renderer fontconfig support.

chrome/renderer/renderer_sandbox_support_linux.cc

Index: chrome/renderer/renderer_sandbox_support_linux.cc
diff --git a/chrome/renderer/renderer_sandbox_support_linux.cc b/chrome/renderer/renderer_sandbox_support_linux.cc
index f1d03e3ac4d5c8c4faba23ca464211eb4a30d605..e06232dcf0b0131a762217475d6651471611e5ad 100644
--- a/chrome/renderer/renderer_sandbox_support_linux.cc
+++ b/chrome/renderer/renderer_sandbox_support_linux.cc
@@ -4,8 +4,10 @@
 
 #include "chrome/renderer/renderer_sandbox_support_linux.h"
 
+#include "base/eintr_wrapper.h"
 #include "base/global_descriptors_posix.h"
 #include "base/pickle.h"
+#include "base/scoped_ptr.h"
 #include "base/unix_domain_socket_posix.h"
 #include "chrome/common/chrome_descriptors.h"
 #include "chrome/common/sandbox_methods_linux.h"
@@ -87,4 +89,72 @@ int MakeSharedMemorySegmentViaIPC(size_t length) {
   return result_fd;
 }
 
+int MatchFontWithFallback(const std::string& family, bool bold,
+                          bool italic, uint32_t microsoft_charset) {
+  Pickle request;
+  request.WriteInt(LinuxSandbox::METHOD_MATCH_WITH_FALLBACK);
+  request.WriteString(family);
+  request.WriteBool(bold);
+  request.WriteBool(italic);
+  request.WriteUInt32(microsoft_charset);
+  uint8_t reply_buf[64];
+  int fd = -1;
+  base::SendRecvMsg(GetSandboxFD(), reply_buf, sizeof(reply_buf),
+                    &fd, request);
+  return fd;
+}
+
+bool GetFontTable(uint8_t** output, size_t* output_length,
+                  int fd, uint32_t table) {
+  unsigned num_tables;
+  uint8_t num_tables_buf[2];
+
+  ssize_t n = HANDLE_EINTR(pread(fd, &num_tables_buf, sizeof(num_tables_buf),
+                           4 /* skip the font type */));
+  if (n != sizeof(num_tables_buf))
+    return false;
+
+  num_tables = static_cast<unsigned>(num_tables_buf[0]) << 8 |
+               num_tables_buf[1];
+
+  // The size in bytes of an entry in the table directory.
+  static const unsigned kTableEntrySize = 16;
+  scoped_array<uint8_t> table_entries(
+      new uint8_t[num_tables * kTableEntrySize]);
+  n = HANDLE_EINTR(pread(fd, table_entries.get(), num_tables * kTableEntrySize,
+                         12 /* skip the SFNT header */));
+  if (n != num_tables * kTableEntrySize)
+    return false;
+
+  size_t offset;
+  size_t length = 0;
+  for (unsigned i = 0; i < num_tables; i++) {
+    const uint8_t* entry = table_entries.get() + i * kTableEntrySize;
+    if (memcmp(entry, &table, sizeof(table)) == 0) {
+      offset = static_cast<size_t>(entry[8]) << 24 |
+               static_cast<size_t>(entry[9]) << 16 |
+               static_cast<size_t>(entry[10]) << 8  |
+               static_cast<size_t>(entry[11]);
+      length = static_cast<size_t>(entry[12]) << 24 |
+               static_cast<size_t>(entry[13]) << 16 |
+               static_cast<size_t>(entry[14]) << 8  |
+               static_cast<size_t>(entry[15]);
+
+      break;
+    }
+  }
+
+  if (!length)
+    return false;
+
+  *output = new uint8_t[length];
+  n = HANDLE_EINTR(pread(fd, *output, length, offset));
+  if (n != static_cast<ssize_t>(length)) {
+    delete[] *output;
+    return false;
+  }
+  *output_length = length;
+  return true;
+}
+
 }  // namespace render_sandbox_support