Issue #1859 - Part 3: Replace bzip2 handling in MAR files with xz.

Since there really is no need to add file detection logic to the updater
if updating through AUS is old->new only anyway, replacing bzip2
handling with xz handling is fine, instead of adding it.
Considering the far superior compression of LZMA and MAR not being
a common archive format anyway, let's just K.I.S.S. it :)

modules/libmar/src/mar.h

@@ -109,7 +109,7 @@ int mar_enum_items(MarFile *mar, MarItemCallback callback, void *data);
  * @return          The number of bytes written or a negative value if an
  *                  error occurs.
  */
-int mar_read(MarFile *mar, const MarItem *item, int offset, char *buf,
+int mar_read(MarFile *mar, const MarItem *item, int offset, uint8_t *buf,
              int bufsize);
 
 /**

modules/libmar/src/mar_extract.c

@@ -37,7 +37,7 @@ static int mar_ensure_parent_dir(const char *path)
 
 static int mar_test_callback(MarFile *mar, const MarItem *item, void *unused) {
   FILE *fp;
-  char buf[BLOCKSIZE];
+  uint8_t buf[BLOCKSIZE];
   int fd, len, offset = 0;
 
   if (mar_ensure_parent_dir(item->name))

modules/libmar/src/mar_read.c

@@ -530,7 +530,7 @@ int mar_enum_items(MarFile *mar, MarItemCallback callback, void *closure) {
   return 0;
 }
 
-int mar_read(MarFile *mar, const MarItem *item, int offset, char *buf,
+int mar_read(MarFile *mar, const MarItem *item, int offset, uint8_t *buf,
              int bufsize) {
   int nr;
 

toolkit/mozapps/update/common/errors.h

@@ -46,7 +46,7 @@
 #define WRITE_ERROR_ACCESS_DENIED 35
 // #define WRITE_ERROR_SHARING_VIOLATION 36 // Replaced with errors 46-48
 #define WRITE_ERROR_CALLBACK_APP 37
-#define UNEXPECTED_BZIP_ERROR 39
+#define UNEXPECTED_XZ_ERROR 39
 #define UNEXPECTED_MAR_ERROR 40
 #define UNEXPECTED_BSPATCH_ERROR 41
 #define UNEXPECTED_FILE_OPERATION_ERROR 42

toolkit/mozapps/update/updater/archivereader.cpp

@@ -1,5 +1,4 @@
 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* vim:set ts=2 sw=2 sts=2 et cindent: */
 /* 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/. */
@@ -15,6 +14,9 @@
 #include "updatehelper.h"
 #endif
 
+#define XZ_USE_CRC64
+#include "xz.h"
+
 // These are generated at compile time based on the DER file for the channel
 // being used
 #ifdef MOZ_VERIFY_MAR_SIGNATURE
@@ -36,10 +38,10 @@
 # include <io.h>
 #endif
 
-static int inbuf_size  = 262144;
-static int outbuf_size = 262144;
-static char *inbuf  = nullptr;
-static char *outbuf = nullptr;
+static size_t inbuf_size  = 262144;
+static size_t outbuf_size = 262144;
+static uint8_t *inbuf  = nullptr;
+static uint8_t *outbuf = nullptr;
 
 /**
  * Performs a verification on the opened MAR file with the passed in
@@ -182,22 +184,22 @@ ArchiveReader::Open(const NS_tchar *path)
     Close();
 
   if (!inbuf) {
-    inbuf = (char *)malloc(inbuf_size);
+    inbuf = (uint8_t *)malloc(inbuf_size);
     if (!inbuf) {
       // Try again with a smaller buffer.
       inbuf_size = 1024;
-      inbuf = (char *)malloc(inbuf_size);
+      inbuf = (uint8_t *)malloc(inbuf_size);
       if (!inbuf)
         return ARCHIVE_READER_MEM_ERROR;
     }
   }
 
   if (!outbuf) {
-    outbuf = (char *)malloc(outbuf_size);
+    outbuf = (uint8_t *)malloc(outbuf_size);
     if (!outbuf) {
       // Try again with a smaller buffer.
       outbuf_size = 1024;
-      outbuf = (char *)malloc(outbuf_size);
+      outbuf = (uint8_t *)malloc(outbuf_size);
       if (!outbuf)
         return ARCHIVE_READER_MEM_ERROR;
     }
@@ -211,6 +213,9 @@ ArchiveReader::Open(const NS_tchar *path)
   if (!mArchive)
     return READ_ERROR;
 
+  xz_crc32_init();
+  xz_crc64_init();
+
   return OK;
 }
 
@@ -273,12 +278,21 @@ ArchiveReader::ExtractItemToStream(const MarItem *item, FILE *fp)
 {
   /* decompress the data chunk by chunk */
 
-  bz_stream strm;
-  int offset, inlen, outlen, ret = OK;
+  int offset, inlen, ret = OK;
+  struct xz_buf strm = { 0 };
+  enum xz_ret xz_rv = XZ_OK;
 
-  memset(&strm, 0, sizeof(strm));
-  if (BZ2_bzDecompressInit(&strm, 0, 0) != BZ_OK)
-    return UNEXPECTED_BZIP_ERROR;
+  struct xz_dec * dec = xz_dec_init(XZ_DYNALLOC, 64 * 1024 * 1024);
+  if (!dec) {
+    return UNEXPECTED_XZ_ERROR;
+  }
+
+  strm.in = inbuf;
+  strm.in_pos = 0;
+  strm.in_size = 0;
+  strm.out = outbuf;
+  strm.out_pos = 0;
+  strm.out_size = outbuf_size;
 
   offset = 0;
   for (;;) {
@@ -287,38 +301,50 @@ ArchiveReader::ExtractItemToStream(const MarItem *item, FILE *fp)
       break;
     }
 
-    if (offset < (int) item->length && strm.avail_in == 0) {
+    if (offset < (int) item->length && strm.in_pos == strm.in_size) {
       inlen = mar_read(mArchive, item, offset, inbuf, inbuf_size);
-      if (inlen <= 0)
-        return READ_ERROR;
+      if (inlen <= 0) {
+        ret = READ_ERROR;
+        break;
+      }
       offset += inlen;
-      strm.next_in = inbuf;
-      strm.avail_in = inlen;
+      strm.in_size = inlen;
+      strm.in_pos = 0;
     }
 
-    strm.next_out = outbuf;
-    strm.avail_out = outbuf_size;
+    xz_rv = xz_dec_run(dec, &strm);
 
-    ret = BZ2_bzDecompress(&strm);
-    if (ret != BZ_OK && ret != BZ_STREAM_END) {
-      ret = UNEXPECTED_BZIP_ERROR;
-      break;
-    }
-
-    outlen = outbuf_size - strm.avail_out;
-    if (outlen) {
-      if (fwrite(outbuf, outlen, 1, fp) != 1) {
+    if (strm.out_pos == outbuf_size) {
+      if (fwrite(outbuf, 1, strm.out_pos, fp) != strm.out_pos) {
         ret = WRITE_ERROR_EXTRACT;
         break;
       }
+
+      strm.out_pos = 0;
     }
 
-    if (ret == BZ_STREAM_END) {
-      ret = OK;
+    if (xz_rv == XZ_OK) {
+      // There is still more data to decompress.
+      continue;
+    }
+
+    // The return value of xz_dec_run is not XZ_OK and if it isn't XZ_STREAM_END
+    // an error has occured.
+    if (xz_rv != XZ_STREAM_END) {
+      ret = UNEXPECTED_XZ_ERROR;
       break;
     }
+
+    // Write out the remainder of the decompressed data. In the case of
+    // strm.out_pos == 0 this is needed to create empty files included in the
+    // mar file.
+    if (fwrite(outbuf, 1, strm.out_pos, fp) != strm.out_pos) {
+      ret = WRITE_ERROR_EXTRACT;
+    }
+
+    break;
   }
 
-  BZ2_bzDecompressEnd(&strm);
+  xz_dec_end(dec);
   return ret;
 }

toolkit/mozapps/update/updater/updater-common.build

@@ -57,6 +57,7 @@ else:
 
 USE_LIBS += [
     'mar',
+    'xz-embedded',
 ]
 
 if CONFIG['MOZ_SYSTEM_BZ2']: