void init_(zip_format format, int level_, dict_type dict_, heap* h, int strategy_){
if (h){
zstream.zalloc = zip_malloc;
zstream.zfree = zip_free;
zstream.opaque = h;
}
if(deflateInit2(&zstream, level_, Z_DEFLATED, get_winbits(format, MAX_WBITS), MAX_MEM_LEVEL, strategy_) != Z_OK)
AIO_THROW(deflate_exception)("deflateInit2 failed");
if (!dict_.empty() && (deflateSetDictionary(&zstream, (const Bytef*)dict_.begin(), uInt(dict_.size())) != Z_OK))
AIO_THROW(deflate_exception)("deflateSetDictionary failed");
}
const GzipHeaderCodec::ZlibContext* GzipHeaderCodec::getZlibContext(
SPDYVersionSettings versionSettings, int compressionLevel) {
static folly::ThreadLocal<ZlibContextMap> zlibContexts_;
ZlibConfig zlibConfig(versionSettings.version, compressionLevel);
auto match = zlibContexts_->find(zlibConfig);
if (match != zlibContexts_->end()) {
return match->second.get();
} else {
// This is the first request for the specified SPDY version and compression
// level in this thread, so we need to construct the initial compressor and
// decompressor contexts.
auto newContext = folly::make_unique<ZlibContext>();
newContext->deflater.zalloc = Z_NULL;
newContext->deflater.zfree = Z_NULL;
newContext->deflater.opaque = Z_NULL;
newContext->deflater.avail_in = 0;
newContext->deflater.next_in = Z_NULL;
int windowBits = (compressionLevel == Z_NO_COMPRESSION) ? 8 : 11;
int r = deflateInit2(
&(newContext->deflater),
compressionLevel,
Z_DEFLATED, // compression method
windowBits, // log2 of the compression window size, negative value
// means raw deflate output format w/o libz header
1, // memory size for internal compression state, 1-9
Z_DEFAULT_STRATEGY);
CHECK(r == Z_OK);
if (compressionLevel != Z_NO_COMPRESSION) {
r = deflateSetDictionary(&(newContext->deflater), versionSettings.dict,
versionSettings.dictSize);
CHECK(r == Z_OK);
}
newContext->inflater.zalloc = Z_NULL;
newContext->inflater.zfree = Z_NULL;
newContext->inflater.opaque = Z_NULL;
newContext->inflater.avail_in = 0;
newContext->inflater.next_in = Z_NULL;
r = inflateInit(&(newContext->inflater));
CHECK(r == Z_OK);
auto result = newContext.get();
zlibContexts_->emplace(zlibConfig, std::move(newContext));
return result;
}
}
/*
zlib.deflate(
sink: function | { write: function [, close: function, flush: function] },
compression level, [Z_DEFAILT_COMPRESSION]
method, [Z_DEFLATED]
windowBits, [15]
memLevel, [8]
strategy, [Z_DEFAULT_STRATEGY]
dictionary: [""]
)
*/
static int lzlib_deflate(lua_State *L) {
int level, method, windowBits, memLevel, strategy;
lz_stream *s;
const char *dictionary;
size_t dictionary_len;
if (lua_istable(L, 1) || lua_isuserdata(L, 1)) {
/* is there a :write function? */
lua_getfield(L, 1, "write");
if (!lua_isfunction(L, -1)) {
luaL_argerror(L, 1, "output parameter does not provide :write function");
}
lua_pop(L, 1);
}
else if (!lua_isfunction(L, 1)) {
luaL_argerror(L, 1, "output parameter must be a function, table or userdata value");
}
level = luaL_optint(L, 2, Z_DEFAULT_COMPRESSION);
method = luaL_optint(L, 3, Z_DEFLATED);
windowBits = luaL_optint(L, 4, 15);
memLevel = luaL_optint(L, 5, 8);
strategy = luaL_optint(L, 6, Z_DEFAULT_STRATEGY);
dictionary = luaL_optlstring(L, 7, NULL, &dictionary_len);
s = lzstream_new(L, 1);
if (deflateInit2(&s->zstream, level, method, windowBits, memLevel, strategy) != Z_OK) {
lua_pushliteral(L, "call to deflateInit2 failed");
lua_error(L);
}
if (dictionary) {
if (deflateSetDictionary(&s->zstream, (const Bytef *) dictionary, dictionary_len) != Z_OK) {
lua_pushliteral(L, "call to deflateSetDictionnary failed");
lua_error(L);
}
}
s->state = LZ_DEFLATE;
return 1;
}
JNIEXPORT void JNICALL
Java_java_util_zip_Deflater_setDictionary(JNIEnv *env, jclass cls, jlong strm,
jarray b, jint off, jint len)
{
Bytef *buf = (*env)->GetPrimitiveArrayCritical(env, b, 0);
int res;
if (buf == 0) {/* out of memory */
return;
}
res = deflateSetDictionary((z_stream *)jlong_to_ptr(strm), buf + off, len);
(*env)->ReleasePrimitiveArrayCritical(env, b, buf, 0);
switch (res) {
case Z_OK:
break;
case Z_STREAM_ERROR:
JNU_ThrowIllegalArgumentException(env, 0);
break;
default:
JNU_ThrowInternalError(env, ((z_stream *)jlong_to_ptr(strm))->msg);
break;
}
}
int SzipCompress::do_compress(Buffer &origBuf, Buffer &outBuf,
const unsigned char *aDict, size_t aDictSize,
SeekableZStream::FilterId aFilter)
{
size_t origSize = origBuf.GetLength();
MOZ_ASSERT(origSize != 0);
/* Expected total number of chunks */
size_t nChunks = ((origSize + chunkSize - 1) / chunkSize);
/* The first chunk is going to be stored after the header, the dictionary
* and the offset table */
size_t offset = sizeof(SeekableZStreamHeader) + aDictSize
+ nChunks * sizeof(uint32_t);
if (offset >= origSize)
return 1;
/* Allocate a buffer the size of the uncompressed data: we don't want
* a compressed file larger than that anyways. */
if (!outBuf.Resize(origSize)) {
log("Couldn't allocate output buffer: %s", strerror(errno));
return 1;
}
SeekableZStreamHeader *header = new (outBuf) SeekableZStreamHeader;
unsigned char *dictionary = static_cast<unsigned char *>(
outBuf + sizeof(SeekableZStreamHeader));
le_uint32 *entry =
reinterpret_cast<le_uint32 *>(dictionary + aDictSize);
/* Initialize header */
header->chunkSize = chunkSize;
header->dictSize = aDictSize;
header->totalSize = offset;
header->windowBits = -SzipCompress::winSizeLog; // Raw stream,
// window size of 32k.
header->filter = aFilter;
if (aDictSize)
memcpy(dictionary, aDict, aDictSize);
/* Initialize zlib structure */
z_stream zStream;
memset(&zStream, 0, sizeof(zStream));
zStream.avail_out = origSize - offset;
zStream.next_out = static_cast<Bytef*>(outBuf) + offset;
size_t avail = 0;
size_t size = origSize;
unsigned char *data = reinterpret_cast<unsigned char *>(
static_cast<void *>(origBuf));
while (size) {
avail = std::min(size, chunkSize);
/* Compress chunk */
int ret = deflateInit2(&zStream, 9, Z_DEFLATED, header->windowBits,
MAX_MEM_LEVEL, Z_DEFAULT_STRATEGY);
if (aDictSize)
deflateSetDictionary(&zStream, dictionary, aDictSize);
MOZ_ASSERT(ret == Z_OK);
zStream.avail_in = avail;
zStream.next_in = data;
ret = deflate(&zStream, Z_FINISH);
MOZ_ASSERT(ret == Z_STREAM_END);
ret = deflateEnd(&zStream);
MOZ_ASSERT(ret == Z_OK);
if (zStream.avail_out <= 0)
return 1;
size_t len = origSize - offset - zStream.avail_out;
/* Adjust headers */
header->totalSize += len;
*entry++ = offset;
header->nChunks++;
/* Prepare for next iteration */
size -= avail;
data += avail;
offset += len;
}
header->lastChunkSize = avail;
MOZ_ASSERT(header->totalSize == offset);
if (!outBuf.Resize(offset)) {
log("Error truncating output: %s", strerror(errno));
return 1;
}
MOZ_ASSERT(header->nChunks == nChunks);
return 0;
}
int streaming_commons_deflate_set_dictionary(z_stream *stream, const char* dictionary,
unsigned int dictLength) {
return deflateSetDictionary(stream, dictionary, dictLength);
}
int Sg_DeflateSetDictionary(SgZStream *strm, SgByteVector *dict)
{
return deflateSetDictionary(strm->strm,
SG_BVECTOR_ELEMENTS(dict),
SG_BVECTOR_SIZE(dict));
}
static ErlDrvSSizeT zlib_ctl(ErlDrvData drv_data, unsigned int command, char *buf,
ErlDrvSizeT len, char **rbuf, ErlDrvSizeT rlen)
{
ZLibData* d = (ZLibData*)drv_data;
int res;
switch(command) {
case DEFLATE_INIT:
if (len != 4) goto badarg;
if (d->state != ST_NONE) goto badarg;
res = deflateInit(&d->s, i32(buf));
if (res == Z_OK) {
d->state = ST_DEFLATE;
d->want_crc = 0;
d->crc = crc32(0L, Z_NULL, 0);
}
return zlib_return(res, rbuf, rlen);
case DEFLATE_INIT2: {
int wbits;
if (len != 20) goto badarg;
if (d->state != ST_NONE) goto badarg;
wbits = i32(buf+8);
res = deflateInit2(&d->s, i32(buf), i32(buf+4), wbits,
i32(buf+12), i32(buf+16));
if (res == Z_OK) {
d->state = ST_DEFLATE;
d->want_crc = (wbits < 0);
d->crc = crc32(0L, Z_NULL, 0);
}
return zlib_return(res, rbuf, rlen);
}
case DEFLATE_SETDICT:
if (d->state != ST_DEFLATE) goto badarg;
res = deflateSetDictionary(&d->s, (unsigned char*)buf, len);
if (res == Z_OK) {
return zlib_value(d->s.adler, rbuf, rlen);
} else {
return zlib_return(res, rbuf, rlen);
}
case DEFLATE_RESET:
if (len != 0) goto badarg;
if (d->state != ST_DEFLATE) goto badarg;
driver_deq(d->port, driver_sizeq(d->port));
res = deflateReset(&d->s);
return zlib_return(res, rbuf, rlen);
case DEFLATE_END:
if (len != 0) goto badarg;
if (d->state != ST_DEFLATE) goto badarg;
driver_deq(d->port, driver_sizeq(d->port));
res = deflateEnd(&d->s);
d->state = ST_NONE;
return zlib_return(res, rbuf, rlen);
case DEFLATE_PARAMS:
if (len != 8) goto badarg;
if (d->state != ST_DEFLATE) goto badarg;
res = deflateParams(&d->s, i32(buf), i32(buf+4));
return zlib_return(res, rbuf, rlen);
case DEFLATE:
if (d->state != ST_DEFLATE) goto badarg;
if (len != 4) goto badarg;
res = zlib_deflate(d, i32(buf));
return zlib_return(res, rbuf, rlen);
case INFLATE_INIT:
if (len != 0) goto badarg;
if (d->state != ST_NONE) goto badarg;
res = inflateInit(&d->s);
if (res == Z_OK) {
d->state = ST_INFLATE;
d->inflate_eos_seen = 0;
d->want_crc = 0;
d->crc = crc32(0L, Z_NULL, 0);
}
return zlib_return(res, rbuf, rlen);
case INFLATE_INIT2: {
int wbits;
if (len != 4) goto badarg;
if (d->state != ST_NONE) goto badarg;
wbits = i32(buf);
res = inflateInit2(&d->s, wbits);
if (res == Z_OK) {
d->state = ST_INFLATE;
d->inflate_eos_seen = 0;
d->want_crc = (wbits < 0);
d->crc = crc32(0L, Z_NULL, 0);
}
return zlib_return(res, rbuf, rlen);
}
case INFLATE_SETDICT:
if (d->state != ST_INFLATE) goto badarg;
res = inflateSetDictionary(&d->s, (unsigned char*)buf, len);
return zlib_return(res, rbuf, rlen);
case INFLATE_SYNC:
if (d->state != ST_INFLATE) goto badarg;
if (len != 0) goto badarg;
if (driver_sizeq(d->port) == 0) {
res = Z_BUF_ERROR;
} else {
int vlen;
SysIOVec* iov = driver_peekq(d->port, &vlen);
d->s.next_in = iov[0].iov_base;
d->s.avail_in = iov[0].iov_len;
res = inflateSync(&d->s);
}
return zlib_return(res, rbuf, rlen);
case INFLATE_RESET:
if (d->state != ST_INFLATE) goto badarg;
if (len != 0) goto badarg;
driver_deq(d->port, driver_sizeq(d->port));
res = inflateReset(&d->s);
d->inflate_eos_seen = 0;
return zlib_return(res, rbuf, rlen);
case INFLATE_END:
if (d->state != ST_INFLATE) goto badarg;
if (len != 0) goto badarg;
driver_deq(d->port, driver_sizeq(d->port));
res = inflateEnd(&d->s);
if (res == Z_OK && d->inflate_eos_seen == 0) {
res = Z_DATA_ERROR;
}
d->state = ST_NONE;
return zlib_return(res, rbuf, rlen);
case INFLATE:
if (d->state != ST_INFLATE) goto badarg;
if (len != 4) goto badarg;
res = zlib_inflate(d, i32(buf));
if (res == Z_NEED_DICT) {
return zlib_value2(3, d->s.adler, rbuf, rlen);
} else {
return zlib_return(res, rbuf, rlen);
}
case GET_QSIZE:
return zlib_value(driver_sizeq(d->port), rbuf, rlen);
case GET_BUFSZ:
return zlib_value(d->binsz_need, rbuf, rlen);
case SET_BUFSZ: {
int need;
if (len != 4) goto badarg;
need = i32(buf);
if ((need < 16) || (need > 0x00ffffff))
goto badarg;
if (d->binsz_need != need) {
d->binsz_need = need;
if (d->bin != NULL) {
if (d->s.avail_out == d->binsz) {
driver_free_binary(d->bin);
d->bin = NULL;
d->binsz = 0;
}
else
zlib_output(d);
}
}
return zlib_return(Z_OK, rbuf, rlen);
}
case CRC32_0:
return zlib_value(d->crc, rbuf, rlen);
case CRC32_1: {
uLong crc = crc32(0L, Z_NULL, 0);
crc = crc32(crc, (unsigned char*) buf, len);
return zlib_value(crc, rbuf, rlen);
}
case CRC32_2: {
uLong crc;
if (len < 4) goto badarg;
crc = (unsigned int) i32(buf);
crc = crc32(crc, (unsigned char*) buf+4, len-4);
return zlib_value(crc, rbuf, rlen);
}
case ADLER32_1: {
uLong adler = adler32(0L, Z_NULL, 0);
adler = adler32(adler, (unsigned char*) buf, len);
return zlib_value(adler, rbuf, rlen);
}
case ADLER32_2: {
uLong adler;
if (len < 4) goto badarg;
adler = (unsigned int) i32(buf);
adler = adler32(adler, (unsigned char*) buf+4, len-4);
return zlib_value(adler, rbuf, rlen);
}
case CRC32_COMBINE: {
uLong crc, crc1, crc2, len2;
if (len != 12) goto badarg;
crc1 = (unsigned int) i32(buf);
crc2 = (unsigned int) i32(buf+4);
len2 = (unsigned int) i32(buf+8);
crc = crc32_combine(crc1, crc2, len2);
return zlib_value(crc, rbuf, rlen);
}
case ADLER32_COMBINE: {
uLong adler, adler1, adler2, len2;
if (len != 12) goto badarg;
adler1 = (unsigned int) i32(buf);
adler2 = (unsigned int) i32(buf+4);
len2 = (unsigned int) i32(buf+8);
adler = adler32_combine(adler1, adler2, len2);
return zlib_value(adler, rbuf, rlen);
}
}
badarg:
errno = EINVAL;
return zlib_return(Z_ERRNO, rbuf, rlen);
}
int
ImagingZipEncode(Imaging im, ImagingCodecState state, UINT8* buf, int bytes)
{
ZIPSTATE* context = (ZIPSTATE*) state->context;
int err;
int compress_level, compress_type;
UINT8* ptr;
int i, bpp, s, sum;
ImagingSectionCookie cookie;
if (!state->state) {
/* Initialization */
/* Valid modes are ZIP_PNG, ZIP_PNG_PALETTE, and ZIP_TIFF */
/* overflow check for malloc */
if (state->bytes > INT_MAX - 1) {
state->errcode = IMAGING_CODEC_MEMORY;
return -1;
}
/* Expand standard buffer to make room for the filter selector,
and allocate filter buffers */
free(state->buffer);
/* malloc check ok, overflow checked above */
state->buffer = (UINT8*) malloc(state->bytes+1);
context->previous = (UINT8*) malloc(state->bytes+1);
context->prior = (UINT8*) malloc(state->bytes+1);
context->up = (UINT8*) malloc(state->bytes+1);
context->average = (UINT8*) malloc(state->bytes+1);
context->paeth = (UINT8*) malloc(state->bytes+1);
if (!state->buffer || !context->previous || !context->prior ||
!context->up || !context->average || !context->paeth) {
free(context->paeth);
free(context->average);
free(context->up);
free(context->prior);
free(context->previous);
state->errcode = IMAGING_CODEC_MEMORY;
return -1;
}
/* Initialise filter buffers */
state->buffer[0] = 0;
context->prior[0] = 1;
context->up[0] = 2;
context->average[0] = 3;
context->paeth[0] = 4;
/* Initialise previous buffer to black */
memset(context->previous, 0, state->bytes+1);
/* Setup compression context */
context->z_stream.zalloc = (alloc_func)0;
context->z_stream.zfree = (free_func)0;
context->z_stream.opaque = (voidpf)0;
context->z_stream.next_in = 0;
context->z_stream.avail_in = 0;
compress_level = (context->optimize) ? Z_BEST_COMPRESSION
: context->compress_level;
if (context->compress_type == -1) {
compress_type = (context->mode == ZIP_PNG) ? Z_FILTERED
: Z_DEFAULT_STRATEGY;
} else {
compress_type = context->compress_type;
}
err = deflateInit2(&context->z_stream,
/* compression level */
compress_level,
/* compression method */
Z_DEFLATED,
/* compression memory resources */
15, 9,
/* compression strategy (image data are filtered)*/
compress_type);
if (err < 0) {
state->errcode = IMAGING_CODEC_CONFIG;
return -1;
}
if (context->dictionary && context->dictionary_size > 0) {
err = deflateSetDictionary(&context->z_stream, (unsigned char *)context->dictionary,
context->dictionary_size);
if (err < 0) {
state->errcode = IMAGING_CODEC_CONFIG;
return -1;
}
}
/* Ready to decode */
state->state = 1;
}
/* Setup the destination buffer */
context->z_stream.next_out = buf;
context->z_stream.avail_out = bytes;
if (context->z_stream.next_in && context->z_stream.avail_in > 0) {
/* We have some data from previous round, deflate it first */
err = deflate(&context->z_stream, Z_NO_FLUSH);
if (err < 0) {
/* Something went wrong inside the compression library */
if (err == Z_DATA_ERROR)
state->errcode = IMAGING_CODEC_BROKEN;
else if (err == Z_MEM_ERROR)
state->errcode = IMAGING_CODEC_MEMORY;
else
state->errcode = IMAGING_CODEC_CONFIG;
free(context->paeth);
free(context->average);
free(context->up);
free(context->prior);
free(context->previous);
deflateEnd(&context->z_stream);
return -1;
}
}
ImagingSectionEnter(&cookie);
for (;;) {
switch (state->state) {
case 1:
/* Compress image data */
while (context->z_stream.avail_out > 0) {
if (state->y >= state->ysize) {
/* End of image; now flush compressor buffers */
state->state = 2;
break;
}
/* Stuff image data into the compressor */
state->shuffle(state->buffer+1,
(UINT8*) im->image[state->y + state->yoff] +
state->xoff * im->pixelsize,
state->xsize);
state->y++;
context->output = state->buffer;
if (context->mode == ZIP_PNG) {
/* Filter the image data. For each line, select
the filter that gives the least total distance
from zero for the filtered data (taken from
LIBPNG) */
bpp = (state->bits + 7) / 8;
/* 0. No filter */
for (i = 1, sum = 0; i <= state->bytes; i++) {
UINT8 v = state->buffer[i];
sum += (v < 128) ? v : 256 - v;
}
/* 2. Up. We'll test this first to save time when
an image line is identical to the one above. */
if (sum > 0) {
for (i = 1, s = 0; i <= state->bytes; i++) {
UINT8 v = state->buffer[i] - context->previous[i];
context->up[i] = v;
s += (v < 128) ? v : 256 - v;
}
if (s < sum) {
context->output = context->up;
sum = s; /* 0 if line was duplicated */
}
}
/* 1. Prior */
if (sum > 0) {
for (i = 1, s = 0; i <= bpp; i++) {
UINT8 v = state->buffer[i];
context->prior[i] = v;
s += (v < 128) ? v : 256 - v;
}
for (; i <= state->bytes; i++) {
UINT8 v = state->buffer[i] - state->buffer[i-bpp];
context->prior[i] = v;
s += (v < 128) ? v : 256 - v;
}
if (s < sum) {
context->output = context->prior;
sum = s; /* 0 if line is solid */
}
}
/* 3. Average (not very common in real-life images,
so its only used with the optimize option) */
if (context->optimize && sum > 0) {
for (i = 1, s = 0; i <= bpp; i++) {
UINT8 v = state->buffer[i] - context->previous[i]/2;
context->average[i] = v;
s += (v < 128) ? v : 256 - v;
}
for (; i <= state->bytes; i++) {
UINT8 v = state->buffer[i] -
(state->buffer[i-bpp] + context->previous[i])/2;
context->average[i] = v;
s += (v < 128) ? v : 256 - v;
}
if (s < sum) {
context->output = context->average;
sum = s;
}
}
/* 4. Paeth */
if (sum > 0) {
for (i = 1, s = 0; i <= bpp; i++) {
UINT8 v = state->buffer[i] - context->previous[i];
context->paeth[i] = v;
s += (v < 128) ? v : 256 - v;
}
for (; i <= state->bytes; i++) {
UINT8 v;
int a, b, c;
int pa, pb, pc;
/* fetch pixels */
a = state->buffer[i-bpp];
b = context->previous[i];
c = context->previous[i-bpp];
/* distances to surrounding pixels */
pa = abs(b - c);
pb = abs(a - c);
pc = abs(a + b - 2*c);
/* pick predictor with the shortest distance */
v = state->buffer[i] -
((pa <= pb && pa <= pc) ? a :
(pb <= pc) ? b : c);
context->paeth[i] = v;
s += (v < 128) ? v : 256 - v;
}
if (s < sum) {
context->output = context->paeth;
sum = s;
}
}
}
/* Compress this line */
context->z_stream.next_in = context->output;
context->z_stream.avail_in = state->bytes+1;
err = deflate(&context->z_stream, Z_NO_FLUSH);
if (err < 0) {
/* Something went wrong inside the compression library */
if (err == Z_DATA_ERROR)
state->errcode = IMAGING_CODEC_BROKEN;
else if (err == Z_MEM_ERROR)
state->errcode = IMAGING_CODEC_MEMORY;
else
state->errcode = IMAGING_CODEC_CONFIG;
free(context->paeth);
free(context->average);
free(context->up);
free(context->prior);
free(context->previous);
deflateEnd(&context->z_stream);
ImagingSectionLeave(&cookie);
return -1;
}
/* Swap buffer pointers */
ptr = state->buffer;
state->buffer = context->previous;
context->previous = ptr;
}
if (context->z_stream.avail_out == 0)
break; /* Buffer full */
case 2:
/* End of image data; flush compressor buffers */
while (context->z_stream.avail_out > 0) {
err = deflate(&context->z_stream, Z_FINISH);
if (err == Z_STREAM_END) {
free(context->paeth);
free(context->average);
free(context->up);
free(context->prior);
free(context->previous);
deflateEnd(&context->z_stream);
state->errcode = IMAGING_CODEC_END;
break;
}
if (context->z_stream.avail_out == 0)
break; /* Buffer full */
}
}
ImagingSectionLeave(&cookie);
return bytes - context->z_stream.avail_out;
}
/* Should never ever arrive here... */
state->errcode = IMAGING_CODEC_CONFIG;
ImagingSectionLeave(&cookie);
return -1;
}
/* TODO: cleanup ctx */
static apr_status_t
zlibdict_output_filter(ap_filter_t *f, apr_bucket_brigade *bb)
{
apr_bucket *b;
zlibdict_ctx_t *ctx = f->ctx;
request_rec *r = f->r;
const char *client_accepts;
apr_status_t status = APR_SUCCESS;
apr_pool_t *subpool;
int zerr;
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, f->r,
"triggered zlibdict_output_filter");
/* Do nothing if asked to filter nothing. */
if (APR_BRIGADE_EMPTY(bb)) {
return APR_SUCCESS;
}
/* First time we are called for this response? */
if (!ctx) {
client_accepts = apr_table_get(r->headers_in, "Accept-Encoding");
if (client_accepts == NULL ||
zlibdict__header_contains(r->pool, client_accepts)) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
"Not compressing (no Accept-Encoding: zlibdict)");
ap_remove_output_filter(f);
return ap_pass_brigade(f->next, bb);
}
ctx = f->ctx = apr_pcalloc(r->pool, sizeof(*ctx));
ctx->bb = apr_brigade_create(r->pool, f->c->bucket_alloc);
ctx->buf = apr_palloc(r->pool, DEFAULT_BUFFERSIZE);
/* zstream must be NULL'd out. */
memset(&ctx->zstr, 0, sizeof(z_stream));
zerr = deflateInit2(&ctx->zstr, DEFAULT_COMPRESSION,
Z_DEFLATED,
DEFAULT_WINDOWSIZE, DEFAULT_MEMLEVEL,
Z_DEFAULT_STRATEGY);
deflateSetDictionary(&ctx->zstr, (Bytef *)propfind_dictionary,
strlen(propfind_dictionary));
/* Set Content-Encoding header so our client knows how to handle
this data. */
apr_table_mergen(r->headers_out, "Content-Encoding", "zlibdict");
}
/* Read the data from the handler and compress it with a dictionary. */
for (b = APR_BRIGADE_FIRST(bb);
b != APR_BRIGADE_SENTINEL(bb);
b = APR_BUCKET_NEXT(b)) {
const char *data;
void *write_buf;
size_t len;
size_t buf_size, write_len;
if (APR_BUCKET_IS_EOS(b)) {
deflateEnd(&ctx->zstr);
/* Remove EOS from the old list, and insert into the new. */
APR_BUCKET_REMOVE(b);
APR_BRIGADE_INSERT_TAIL(ctx->bb, b);
return ap_pass_brigade(f->next, ctx->bb);
}
if (APR_BUCKET_IS_METADATA(b))
continue;
status = apr_bucket_read(b, &data, &len, APR_BLOCK_READ);
if (status != APR_SUCCESS)
break;
/* The largest buffer we should need is 0.1% larger than the
compressed data, + 12 bytes. This info comes from zlib.h. */
buf_size = len + (len / 1000) + 13;
apr_pool_create(&subpool, r->pool);
write_buf = apr_palloc(subpool, buf_size);
ctx->zstr.next_in = (Bytef *)data; /* Casting away const! */
ctx->zstr.avail_in = (uInt) len;
zerr = Z_OK;
while (ctx->zstr.avail_in > 0 && zerr != Z_STREAM_END)
{
ctx->zstr.next_out = write_buf;
ctx->zstr.avail_out = (uInt) buf_size;
zerr = deflate(&ctx->zstr, Z_FINISH);
if (zerr < 0)
return -1; /* TODO: fix error */
write_len = buf_size - ctx->zstr.avail_out;
if (write_len > 0) {
apr_bucket *b_out;
b_out = apr_bucket_heap_create(write_buf, len,
NULL, f->c->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(ctx->bb, b_out);
/* Send what we have right now to the next filter. */
status = ap_pass_brigade(f->next, ctx->bb);
if (status != APR_SUCCESS) {
apr_pool_destroy(subpool);
return status;
}
}
apr_pool_destroy(subpool);
}
}
return status;
}
