summaryrefslogtreecommitdiffstats
path: root/modules/libjar/zipwriter/nsDeflateConverter.cpp
blob: 1fead9aa7b2129548cf6a197d020000781219a7f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
/* 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 "StreamFunctions.h"
#include "nsDeflateConverter.h"
#include "nsStringStream.h"
#include "nsComponentManagerUtils.h"
#include "nsCRT.h"
#include "plstr.h"
#include "mozilla/UniquePtr.h"

#define ZLIB_TYPE "deflate"
#define GZIP_TYPE "gzip"
#define X_GZIP_TYPE "x-gzip"

using namespace mozilla;

/**
 * nsDeflateConverter is a stream converter applies the deflate compression
 * method to the data.
 */
NS_IMPL_ISUPPORTS(nsDeflateConverter, nsIStreamConverter, nsIStreamListener,
                  nsIRequestObserver)

nsresult nsDeflateConverter::Init() {
  int zerr;

  mOffset = 0;

  mZstream.zalloc = Z_NULL;
  mZstream.zfree = Z_NULL;
  mZstream.opaque = Z_NULL;

  int32_t window = MAX_WBITS;
  switch (mWrapMode) {
    case WRAP_NONE:
      window = -window;
      break;
    case WRAP_GZIP:
      window += 16;
      break;
    default:
      break;
  }

  zerr = deflateInit2(&mZstream, mLevel, Z_DEFLATED, window, 8,
                      Z_DEFAULT_STRATEGY);
  if (zerr != Z_OK) return NS_ERROR_OUT_OF_MEMORY;

  mZstream.next_out = mWriteBuffer;
  mZstream.avail_out = sizeof(mWriteBuffer);

  // mark the input buffer as empty.
  mZstream.avail_in = 0;
  mZstream.next_in = Z_NULL;

  return NS_OK;
}

NS_IMETHODIMP nsDeflateConverter::Convert(nsIInputStream* aFromStream,
                                          const char* aFromType,
                                          const char* aToType,
                                          nsISupports* aCtxt,
                                          nsIInputStream** _retval) {
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP nsDeflateConverter::AsyncConvertData(const char* aFromType,
                                                   const char* aToType,
                                                   nsIStreamListener* aListener,
                                                   nsISupports* aCtxt) {
  if (mListener) return NS_ERROR_ALREADY_INITIALIZED;

  NS_ENSURE_ARG_POINTER(aListener);

  if (!PL_strncasecmp(aToType, ZLIB_TYPE, sizeof(ZLIB_TYPE) - 1)) {
    mWrapMode = WRAP_ZLIB;
  } else if (!nsCRT::strcasecmp(aToType, GZIP_TYPE) ||
             !nsCRT::strcasecmp(aToType, X_GZIP_TYPE)) {
    mWrapMode = WRAP_GZIP;
  } else {
    mWrapMode = WRAP_NONE;
  }

  nsresult rv = Init();
  NS_ENSURE_SUCCESS(rv, rv);

  mListener = aListener;
  mContext = aCtxt;
  return rv;
}

NS_IMETHODIMP
nsDeflateConverter::GetConvertedType(const nsACString& aFromType,
                                     nsIChannel* aChannel,
                                     nsACString& aToType) {
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP nsDeflateConverter::OnDataAvailable(nsIRequest* aRequest,
                                                  nsIInputStream* aInputStream,
                                                  uint64_t aOffset,
                                                  uint32_t aCount) {
  if (!mListener) return NS_ERROR_NOT_INITIALIZED;

  auto buffer = MakeUnique<char[]>(aCount);
  NS_ENSURE_TRUE(buffer, NS_ERROR_OUT_OF_MEMORY);

  nsresult rv = ZW_ReadData(aInputStream, buffer.get(), aCount);
  NS_ENSURE_SUCCESS(rv, rv);

  // make sure we aren't reading too much
  mZstream.avail_in = aCount;
  mZstream.next_in = (unsigned char*)buffer.get();

  int zerr = Z_OK;
  // deflate loop
  while (mZstream.avail_in > 0 && zerr == Z_OK) {
    zerr = deflate(&mZstream, Z_NO_FLUSH);

    while (mZstream.avail_out == 0) {
      // buffer is full, push the data out to the listener
      rv = PushAvailableData(aRequest);
      NS_ENSURE_SUCCESS(rv, rv);
      zerr = deflate(&mZstream, Z_NO_FLUSH);
    }
  }

  return NS_OK;
}

NS_IMETHODIMP nsDeflateConverter::OnStartRequest(nsIRequest* aRequest) {
  if (!mListener) return NS_ERROR_NOT_INITIALIZED;

  return mListener->OnStartRequest(aRequest);
}

NS_IMETHODIMP nsDeflateConverter::OnStopRequest(nsIRequest* aRequest,
                                                nsresult aStatusCode) {
  if (!mListener) return NS_ERROR_NOT_INITIALIZED;

  nsresult rv;

  int zerr;
  do {
    zerr = deflate(&mZstream, Z_FINISH);
    rv = PushAvailableData(aRequest);
    NS_ENSURE_SUCCESS(rv, rv);
  } while (zerr == Z_OK);

  deflateEnd(&mZstream);

  return mListener->OnStopRequest(aRequest, aStatusCode);
}

nsresult nsDeflateConverter::PushAvailableData(nsIRequest* aRequest) {
  uint32_t bytesToWrite = sizeof(mWriteBuffer) - mZstream.avail_out;
  // We don't need to do anything if there isn't any data
  if (bytesToWrite == 0) return NS_OK;

  MOZ_ASSERT(bytesToWrite <= INT32_MAX);
  nsCOMPtr<nsIInputStream> stream;
  nsresult rv = NS_NewByteInputStream(getter_AddRefs(stream),
                                      Span((char*)mWriteBuffer, bytesToWrite),
                                      NS_ASSIGNMENT_DEPEND);
  NS_ENSURE_SUCCESS(rv, rv);

  rv = mListener->OnDataAvailable(aRequest, stream, mOffset, bytesToWrite);

  // now set the state for 'deflate'
  mZstream.next_out = mWriteBuffer;
  mZstream.avail_out = sizeof(mWriteBuffer);

  mOffset += bytesToWrite;
  return rv;
}