diff options
Diffstat (limited to 'netwerk/protocol/http/nsHttpChunkedDecoder.cpp')
| -rw-r--r-- | netwerk/protocol/http/nsHttpChunkedDecoder.cpp | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/netwerk/protocol/http/nsHttpChunkedDecoder.cpp b/netwerk/protocol/http/nsHttpChunkedDecoder.cpp new file mode 100644 index 000000000..a532c137d --- /dev/null +++ b/netwerk/protocol/http/nsHttpChunkedDecoder.cpp @@ -0,0 +1,168 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* 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/. */ + +// HttpLog.h should generally be included first +#include "HttpLog.h" +#include <errno.h> +#include "nsHttpChunkedDecoder.h" +#include <algorithm> +#include "plstr.h" + +namespace mozilla { +namespace net { + +//----------------------------------------------------------------------------- +// nsHttpChunkedDecoder <public> +//----------------------------------------------------------------------------- + +nsresult +nsHttpChunkedDecoder::HandleChunkedContent(char *buf, + uint32_t count, + uint32_t *contentRead, + uint32_t *contentRemaining) +{ + LOG(("nsHttpChunkedDecoder::HandleChunkedContent [count=%u]\n", count)); + + *contentRead = 0; + + // from RFC2617 section 3.6.1, the chunked transfer coding is defined as: + // + // Chunked-Body = *chunk + // last-chunk + // trailer + // CRLF + // chunk = chunk-size [ chunk-extension ] CRLF + // chunk-data CRLF + // chunk-size = 1*HEX + // last-chunk = 1*("0") [ chunk-extension ] CRLF + // + // chunk-extension = *( ";" chunk-ext-name [ "=" chunk-ext-val ] ) + // chunk-ext-name = token + // chunk-ext-val = token | quoted-string + // chunk-data = chunk-size(OCTET) + // trailer = *(entity-header CRLF) + // + // the chunk-size field is a string of hex digits indicating the size of the + // chunk. the chunked encoding is ended by any chunk whose size is zero, + // followed by the trailer, which is terminated by an empty line. + + while (count) { + if (mChunkRemaining) { + uint32_t amt = std::min(mChunkRemaining, count); + + count -= amt; + mChunkRemaining -= amt; + + *contentRead += amt; + buf += amt; + } + else if (mReachedEOF) + break; // done + else { + uint32_t bytesConsumed = 0; + + nsresult rv = ParseChunkRemaining(buf, count, &bytesConsumed); + if (NS_FAILED(rv)) return rv; + + count -= bytesConsumed; + + if (count) { + // shift buf by bytesConsumed + memmove(buf, buf + bytesConsumed, count); + } + } + } + + *contentRemaining = count; + return NS_OK; +} + +//----------------------------------------------------------------------------- +// nsHttpChunkedDecoder <private> +//----------------------------------------------------------------------------- + +nsresult +nsHttpChunkedDecoder::ParseChunkRemaining(char *buf, + uint32_t count, + uint32_t *bytesConsumed) +{ + NS_PRECONDITION(mChunkRemaining == 0, "chunk remaining should be zero"); + NS_PRECONDITION(count, "unexpected"); + + *bytesConsumed = 0; + + char *p = static_cast<char *>(memchr(buf, '\n', count)); + if (p) { + *p = 0; + count = p - buf; // new length + *bytesConsumed = count + 1; // length + newline + if ((p > buf) && (*(p-1) == '\r')) { // eliminate a preceding CR + *(p-1) = 0; + count--; + } + + // make buf point to the full line buffer to parse + if (!mLineBuf.IsEmpty()) { + mLineBuf.Append(buf, count); + buf = (char *) mLineBuf.get(); + count = mLineBuf.Length(); + } + + if (mWaitEOF) { + if (*buf) { + LOG(("got trailer: %s\n", buf)); + // allocate a header array for the trailers on demand + if (!mTrailers) { + mTrailers = new nsHttpHeaderArray(); + } + mTrailers->ParseHeaderLine(nsDependentCSubstring(buf, count)); + } + else { + mWaitEOF = false; + mReachedEOF = true; + LOG(("reached end of chunked-body\n")); + } + } + else if (*buf) { + char *endptr; + unsigned long parsedval; // could be 64 bit, could be 32 + + // ignore any chunk-extensions + if ((p = PL_strchr(buf, ';')) != nullptr) + *p = 0; + + // mChunkRemaining is an uint32_t! + parsedval = strtoul(buf, &endptr, 16); + mChunkRemaining = (uint32_t) parsedval; + + if ((endptr == buf) || + ((errno == ERANGE) && (parsedval == ULONG_MAX)) || + (parsedval != mChunkRemaining) ) { + LOG(("failed parsing hex on string [%s]\n", buf)); + return NS_ERROR_UNEXPECTED; + } + + // we've discovered the last chunk + if (mChunkRemaining == 0) + mWaitEOF = true; + } + + // ensure that the line buffer is clear + mLineBuf.Truncate(); + } + else { + // save the partial line; wait for more data + *bytesConsumed = count; + // ignore a trailing CR + if (buf[count-1] == '\r') + count--; + mLineBuf.Append(buf, count); + } + + return NS_OK; +} + +} // namespace net +} // namespace mozilla |