Add m-esr52 at 52.6.0

1 files changed, 261 insertions, 0 deletions

diff --git a/mozglue/linker/SeekableZStream.cpp b/mozglue/linker/SeekableZStream.cpp
new file mode 100644
index 000000000..6dd0ef6d5
--- /dev/null
+++ b/mozglue/linker/SeekableZStream.cpp
@@ -0,0 +1,261 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <algorithm>
+#include "SeekableZStream.h"
+#include "Logging.h"
+
+bool
+SeekableZStream::Init(const void *buf, size_t length)
+{
+  const SeekableZStreamHeader *header = SeekableZStreamHeader::validate(buf);
+  if (!header) {
+    ERROR("Not a seekable zstream");
+    return false;
+  }
+
+  buffer = reinterpret_cast<const unsigned char *>(buf);
+  totalSize = header->totalSize;
+  chunkSize = header->chunkSize;
+  lastChunkSize = header->lastChunkSize;
+  windowBits = header->windowBits;
+  dictionary.Init(buffer + sizeof(SeekableZStreamHeader), header->dictSize);
+  offsetTable.Init(buffer + sizeof(SeekableZStreamHeader) + header->dictSize,
+                   header->nChunks);
+  filter = GetFilter(header->filter);
+
+  /* Sanity check */
+  if ((chunkSize == 0) ||
+      (!IsPageAlignedSize(chunkSize)) ||
+      (chunkSize > 8 * PageSize()) ||
+      (offsetTable.numElements() < 1) ||
+      (lastChunkSize == 0) ||
+      (lastChunkSize > chunkSize) ||
+      (length < totalSize)) {
+    ERROR("Malformed or broken seekable zstream");
+    return false;
+  }
+
+  return true;
+}
+
+bool
+SeekableZStream::Decompress(void *where, size_t chunk, size_t length)
+{
+  while (length) {
+    size_t len = std::min(length, static_cast<size_t>(chunkSize));
+    if (!DecompressChunk(where, chunk, len))
+      return false;
+    where = reinterpret_cast<unsigned char *>(where) + len;
+    length -= len;
+    chunk++;
+  }
+  return true;
+}
+
+bool
+SeekableZStream::DecompressChunk(void *where, size_t chunk, size_t length)
+{
+  if (chunk >= offsetTable.numElements()) {
+    ERROR("DecompressChunk: chunk #%" PRIdSize " out of range [0-%" PRIdSize ")",
+        chunk, offsetTable.numElements());
+    return false;
+  }
+
+  bool isLastChunk = (chunk == offsetTable.numElements() - 1);
+
+  size_t chunkLen = isLastChunk ? lastChunkSize : chunkSize;
+
+  if (length == 0 || length > chunkLen)
+    length = chunkLen;
+
+  DEBUG_LOG("DecompressChunk #%" PRIdSize " @%p (%" PRIdSize "/% " PRIdSize ")",
+        chunk, where, length, chunkLen);
+  zxx_stream zStream(&allocator);
+  zStream.avail_in = (isLastChunk ? totalSize : uint32_t(offsetTable[chunk + 1]))
+                     - uint32_t(offsetTable[chunk]);
+  zStream.next_in = const_cast<Bytef *>(buffer + uint32_t(offsetTable[chunk]));
+  zStream.avail_out = length;
+  zStream.next_out = reinterpret_cast<Bytef *>(where);
+
+  /* Decompress chunk */
+  if (inflateInit2(&zStream, windowBits) != Z_OK) {
+    ERROR("inflateInit failed: %s", zStream.msg);
+    return false;
+  }
+  if (dictionary && inflateSetDictionary(&zStream, dictionary,
+                                         dictionary.numElements()) != Z_OK) {
+    ERROR("inflateSetDictionary failed: %s", zStream.msg);
+    return false;
+  }
+  if (inflate(&zStream, (length == chunkLen) ? Z_FINISH : Z_SYNC_FLUSH)
+      != (length == chunkLen) ? Z_STREAM_END : Z_OK) {
+    ERROR("inflate failed: %s", zStream.msg);
+    return false;
+  }
+  if (inflateEnd(&zStream) != Z_OK) {
+    ERROR("inflateEnd failed: %s", zStream.msg);
+    return false;
+  }
+  if (filter)
+    filter(chunk * chunkSize, UNFILTER, (unsigned char *)where, chunkLen);
+
+  return true;
+}
+
+/* Branch/Call/Jump conversion filter for Thumb, derived from xz-utils
+ * by Igor Pavlov and Lasse Collin, published in the public domain */
+static void
+BCJ_Thumb_filter(off_t offset, SeekableZStream::FilterDirection dir,
+                 unsigned char *buf, size_t size)
+{
+  size_t i;
+  for (i = 0; i + 4 <= size; i += 2) {
+    if ((buf[i + 1] & 0xf8) == 0xf0 && (buf[i + 3] & 0xf8) == 0xf8) {
+      uint32_t src = (buf[i] << 11)
+                     | ((buf[i + 1] & 0x07) << 19)
+                     | buf[i + 2]
+                     | ((buf[i + 3] & 0x07) << 8);
+      src <<= 1;
+      uint32_t dest;
+      if (dir == SeekableZStream::FILTER)
+        dest = offset + (uint32_t)(i) + 4 + src;
+      else
+        dest = src - (offset + (uint32_t)(i) + 4);
+
+      dest >>= 1;
+      buf[i] = dest >> 11;
+      buf[i + 1] = 0xf0 | ((dest >> 19) & 0x07);
+      buf[i + 2] = dest;
+      buf[i + 3] = 0xf8 | ((dest >> 8) & 0x07);
+      i += 2;
+    }
+  }
+}
+
+/* Branch/Call/Jump conversion filter for ARM, derived from xz-utils
+ * by Igor Pavlov and Lasse Collin, published in the public domain */
+static void
+BCJ_ARM_filter(off_t offset, SeekableZStream::FilterDirection dir,
+               unsigned char *buf, size_t size)
+{
+  size_t i;
+  for (i = 0; i + 4 <= size; i += 4) {
+    if (buf[i + 3] == 0xeb) {
+      uint32_t src = buf[i]
+                     | (buf[i + 1] << 8)
+                     | (buf[i + 2] << 16);
+      src <<= 2;
+      uint32_t dest;
+      if (dir == SeekableZStream::FILTER)
+        dest = offset + (uint32_t)(i) + 8 + src;
+      else
+        dest = src - (offset + (uint32_t)(i) + 8);
+
+      dest >>= 2;
+      buf[i] = dest;
+      buf[i + 1] = dest >> 8;
+      buf[i + 2] = dest >> 16;
+    }
+  }
+}
+
+/* Branch/Call/Jump conversion filter for x86, derived from xz-utils
+ * by Igor Pavlov and Lasse Collin, published in the public domain */
+
+#define Test86MSByte(b) ((b) == 0 || (b) == 0xff)
+
+static void
+BCJ_X86_filter(off_t offset, SeekableZStream::FilterDirection dir,
+               unsigned char *buf, size_t size)
+{
+  static const bool MASK_TO_ALLOWED_STATUS[8] =
+    { true, true, true, false, true, false, false, false };
+
+  static const uint32_t MASK_TO_BIT_NUMBER[8] =
+    { 0, 1, 2, 2, 3, 3, 3, 3 };
+
+  uint32_t prev_mask = 0;
+  uint32_t prev_pos = 0;
+
+  for (size_t i = 0; i + 5 <= size;) {
+    uint8_t b = buf[i];
+    if (b != 0xe8 && b != 0xe9) {
+      ++i;
+      continue;
+    }
+
+    const uint32_t off = offset + (uint32_t)(i) - prev_pos;
+    prev_pos = offset + (uint32_t)(i);
+
+    if (off > 5) {
+      prev_mask = 0;
+    } else {
+      for (uint32_t i = 0; i < off; ++i) {
+        prev_mask &= 0x77;
+        prev_mask <<= 1;
+      }
+    }
+
+    b = buf[i + 4];
+
+    if (Test86MSByte(b) && MASK_TO_ALLOWED_STATUS[(prev_mask >> 1) & 0x7]
+        && (prev_mask >> 1) < 0x10) {
+
+      uint32_t src = ((uint32_t)(b) << 24)
+                     | ((uint32_t)(buf[i + 3]) << 16)
+                     | ((uint32_t)(buf[i + 2]) << 8)
+                     | (buf[i + 1]);
+
+      uint32_t dest;
+      while (true) {
+        if (dir == SeekableZStream::FILTER)
+          dest = src + (offset + (uint32_t)(i) + 5);
+        else
+          dest = src - (offset + (uint32_t)(i) + 5);
+
+        if (prev_mask == 0)
+          break;
+
+        const uint32_t i = MASK_TO_BIT_NUMBER[prev_mask >> 1];
+
+        b = (uint8_t)(dest >> (24 - i * 8));
+
+        if (!Test86MSByte(b))
+          break;
+
+        src = dest ^ ((1 << (32 - i * 8)) - 1);
+      }
+
+      buf[i + 4] = (uint8_t)(~(((dest >> 24) & 1) - 1));
+      buf[i + 3] = (uint8_t)(dest >> 16);
+      buf[i + 2] = (uint8_t)(dest >> 8);
+      buf[i + 1] = (uint8_t)(dest);
+      i += 5;
+      prev_mask = 0;
+
+    } else {
+      ++i;
+      prev_mask |= 1;
+      if (Test86MSByte(b))
+        prev_mask |= 0x10;
+    }
+  }
+}
+
+SeekableZStream::ZStreamFilter
+SeekableZStream::GetFilter(SeekableZStream::FilterId id)
+{
+  switch (id) {
+  case BCJ_THUMB:
+    return BCJ_Thumb_filter;
+  case BCJ_ARM:
+    return BCJ_ARM_filter;
+  case BCJ_X86:
+    return BCJ_X86_filter;
+  default:
+    return nullptr;
+  }
+  return nullptr;
+}