diff options
Diffstat (limited to 'buckets/deflate_buckets.c')
| -rw-r--r-- | buckets/deflate_buckets.c | 384 |
1 files changed, 384 insertions, 0 deletions
diff --git a/buckets/deflate_buckets.c b/buckets/deflate_buckets.c new file mode 100644 index 0000000..7a8e8e4 --- /dev/null +++ b/buckets/deflate_buckets.c @@ -0,0 +1,384 @@ +/* Copyright 2002-2004 Justin Erenkrantz and Greg Stein + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include <apr_strings.h> + +#include <zlib.h> + +/* This conditional isn't defined anywhere yet. */ +#ifdef HAVE_ZUTIL_H +#include <zutil.h> +#endif + +#include "serf.h" +#include "serf_bucket_util.h" + +/* magic header */ +static char deflate_magic[2] = { '\037', '\213' }; +#define DEFLATE_MAGIC_SIZE 10 +#define DEFLATE_VERIFY_SIZE 8 +#define DEFLATE_BUFFER_SIZE 8096 + +static const int DEFLATE_WINDOW_SIZE = -15; +static const int DEFLATE_MEMLEVEL = 9; + +typedef struct { + serf_bucket_t *stream; + serf_bucket_t *inflate_stream; + + int format; /* Are we 'deflate' or 'gzip'? */ + + enum { + STATE_READING_HEADER, /* reading the gzip header */ + STATE_HEADER, /* read the gzip header */ + STATE_INIT, /* init'ing zlib functions */ + STATE_INFLATE, /* inflating the content now */ + STATE_READING_VERIFY, /* reading the final gzip CRC */ + STATE_VERIFY, /* verifying the final gzip CRC */ + STATE_FINISH, /* clean up after reading body */ + STATE_DONE, /* body is done; we'll return EOF here */ + } state; + + z_stream zstream; + char hdr_buffer[DEFLATE_MAGIC_SIZE]; + unsigned char buffer[DEFLATE_BUFFER_SIZE]; + unsigned long crc; + int windowSize; + int memLevel; + int bufferSize; + + /* How much of the chunk, or the terminator, do we have left to read? */ + apr_size_t stream_left; + + /* How much are we supposed to read? */ + apr_size_t stream_size; + + int stream_status; /* What was the last status we read? */ + +} deflate_context_t; + +/* Inputs a string and returns a long. */ +static unsigned long getLong(unsigned char *string) +{ + return ((unsigned long)string[0]) + | (((unsigned long)string[1]) << 8) + | (((unsigned long)string[2]) << 16) + | (((unsigned long)string[3]) << 24); +} + +serf_bucket_t *serf_bucket_deflate_create( + serf_bucket_t *stream, + serf_bucket_alloc_t *allocator, + int format) +{ + deflate_context_t *ctx; + + ctx = serf_bucket_mem_alloc(allocator, sizeof(*ctx)); + ctx->stream = stream; + ctx->stream_status = APR_SUCCESS; + ctx->inflate_stream = serf_bucket_aggregate_create(allocator); + ctx->format = format; + ctx->crc = 0; + /* zstream must be NULL'd out. */ + memset(&ctx->zstream, 0, sizeof(ctx->zstream)); + + switch (ctx->format) { + case SERF_DEFLATE_GZIP: + ctx->state = STATE_READING_HEADER; + break; + case SERF_DEFLATE_DEFLATE: + /* deflate doesn't have a header. */ + ctx->state = STATE_INIT; + break; + default: + /* Not reachable */ + return NULL; + } + + /* Initial size of gzip header. */ + ctx->stream_left = ctx->stream_size = DEFLATE_MAGIC_SIZE; + + ctx->windowSize = DEFLATE_WINDOW_SIZE; + ctx->memLevel = DEFLATE_MEMLEVEL; + ctx->bufferSize = DEFLATE_BUFFER_SIZE; + + return serf_bucket_create(&serf_bucket_type_deflate, allocator, ctx); +} + +static void serf_deflate_destroy_and_data(serf_bucket_t *bucket) +{ + deflate_context_t *ctx = bucket->data; + + if (ctx->state > STATE_INIT && + ctx->state <= STATE_FINISH) + inflateEnd(&ctx->zstream); + + /* We may have appended inflate_stream into the stream bucket. + * If so, avoid free'ing it twice. + */ + if (ctx->inflate_stream) { + serf_bucket_destroy(ctx->inflate_stream); + } + serf_bucket_destroy(ctx->stream); + + serf_default_destroy_and_data(bucket); +} + +static apr_status_t serf_deflate_read(serf_bucket_t *bucket, + apr_size_t requested, + const char **data, apr_size_t *len) +{ + deflate_context_t *ctx = bucket->data; + unsigned long compCRC, compLen; + apr_status_t status; + const char *private_data; + apr_size_t private_len; + int zRC; + + while (1) { + switch (ctx->state) { + case STATE_READING_HEADER: + case STATE_READING_VERIFY: + status = serf_bucket_read(ctx->stream, ctx->stream_left, + &private_data, &private_len); + + if (SERF_BUCKET_READ_ERROR(status)) { + return status; + } + + memcpy(ctx->hdr_buffer + (ctx->stream_size - ctx->stream_left), + private_data, private_len); + + ctx->stream_left -= private_len; + + if (ctx->stream_left == 0) { + ctx->state++; + if (APR_STATUS_IS_EAGAIN(status)) { + *len = 0; + return status; + } + } + else if (status) { + *len = 0; + return status; + } + break; + case STATE_HEADER: + if (ctx->hdr_buffer[0] != deflate_magic[0] || + ctx->hdr_buffer[1] != deflate_magic[1]) { + return SERF_ERROR_DECOMPRESSION_FAILED; + } + if (ctx->hdr_buffer[3] != 0) { + return SERF_ERROR_DECOMPRESSION_FAILED; + } + ctx->state++; + break; + case STATE_VERIFY: + /* Do the checksum computation. */ + compCRC = getLong((unsigned char*)ctx->hdr_buffer); + if (ctx->crc != compCRC) { + return SERF_ERROR_DECOMPRESSION_FAILED; + } + compLen = getLong((unsigned char*)ctx->hdr_buffer + 4); + if (ctx->zstream.total_out != compLen) { + return SERF_ERROR_DECOMPRESSION_FAILED; + } + ctx->state++; + break; + case STATE_INIT: + zRC = inflateInit2(&ctx->zstream, ctx->windowSize); + if (zRC != Z_OK) { + return SERF_ERROR_DECOMPRESSION_FAILED; + } + ctx->zstream.next_out = ctx->buffer; + ctx->zstream.avail_out = ctx->bufferSize; + ctx->state++; + break; + case STATE_FINISH: + inflateEnd(&ctx->zstream); + serf_bucket_aggregate_prepend(ctx->stream, ctx->inflate_stream); + ctx->inflate_stream = 0; + ctx->state++; + break; + case STATE_INFLATE: + /* Do we have anything already uncompressed to read? */ + status = serf_bucket_read(ctx->inflate_stream, requested, data, + len); + if (SERF_BUCKET_READ_ERROR(status)) { + return status; + } + /* Hide EOF. */ + if (APR_STATUS_IS_EOF(status)) { + status = ctx->stream_status; + if (APR_STATUS_IS_EOF(status)) { + /* We've read all of the data from our stream, but we + * need to continue to iterate until we flush + * out the zlib buffer. + */ + status = APR_SUCCESS; + } + } + if (*len != 0) { + return status; + } + + /* We tried; but we have nothing buffered. Fetch more. */ + + /* It is possible that we maxed out avail_out before + * exhausting avail_in; therefore, continue using the + * previous buffer. Otherwise, fetch more data from + * our stream bucket. + */ + if (ctx->zstream.avail_in == 0) { + /* When we empty our inflated stream, we'll return this + * status - this allow us to eventually pass up EAGAINs. + */ + ctx->stream_status = serf_bucket_read(ctx->stream, + ctx->bufferSize, + &private_data, + &private_len); + + if (SERF_BUCKET_READ_ERROR(ctx->stream_status)) { + return ctx->stream_status; + } + + if (!private_len && APR_STATUS_IS_EAGAIN(ctx->stream_status)) { + *len = 0; + status = ctx->stream_status; + ctx->stream_status = APR_SUCCESS; + return status; + } + + ctx->zstream.next_in = (unsigned char*)private_data; + ctx->zstream.avail_in = private_len; + } + zRC = Z_OK; + while (ctx->zstream.avail_in != 0) { + /* We're full, clear out our buffer, reset, and return. */ + if (ctx->zstream.avail_out == 0) { + serf_bucket_t *tmp; + ctx->zstream.next_out = ctx->buffer; + private_len = ctx->bufferSize - ctx->zstream.avail_out; + + ctx->crc = crc32(ctx->crc, (const Bytef *)ctx->buffer, + private_len); + + /* FIXME: There probably needs to be a free func. */ + tmp = SERF_BUCKET_SIMPLE_STRING_LEN((char *)ctx->buffer, + private_len, + bucket->allocator); + serf_bucket_aggregate_append(ctx->inflate_stream, tmp); + ctx->zstream.avail_out = ctx->bufferSize; + break; + } + zRC = inflate(&ctx->zstream, Z_NO_FLUSH); + + if (zRC == Z_STREAM_END) { + serf_bucket_t *tmp; + + private_len = ctx->bufferSize - ctx->zstream.avail_out; + ctx->crc = crc32(ctx->crc, (const Bytef *)ctx->buffer, + private_len); + /* FIXME: There probably needs to be a free func. */ + tmp = SERF_BUCKET_SIMPLE_STRING_LEN((char *)ctx->buffer, + private_len, + bucket->allocator); + serf_bucket_aggregate_append(ctx->inflate_stream, tmp); + + ctx->zstream.avail_out = ctx->bufferSize; + + /* Push back the remaining data to be read. */ + tmp = serf_bucket_aggregate_create(bucket->allocator); + serf_bucket_aggregate_prepend(tmp, ctx->stream); + ctx->stream = tmp; + + /* We now need to take the remaining avail_in and + * throw it in ctx->stream so our next read picks it up. + */ + tmp = SERF_BUCKET_SIMPLE_STRING_LEN( + (const char*)ctx->zstream.next_in, + ctx->zstream.avail_in, + bucket->allocator); + serf_bucket_aggregate_prepend(ctx->stream, tmp); + + switch (ctx->format) { + case SERF_DEFLATE_GZIP: + ctx->stream_left = ctx->stream_size = + DEFLATE_VERIFY_SIZE; + ctx->state++; + break; + case SERF_DEFLATE_DEFLATE: + /* Deflate does not have a verify footer. */ + ctx->state = STATE_FINISH; + break; + default: + /* Not reachable */ + return APR_EGENERAL; + } + + break; + } + if (zRC != Z_OK) { + return SERF_ERROR_DECOMPRESSION_FAILED; + } + } + /* Okay, we've inflated. Try to read. */ + status = serf_bucket_read(ctx->inflate_stream, requested, data, + len); + /* Hide EOF. */ + if (APR_STATUS_IS_EOF(status)) { + status = ctx->stream_status; + /* If our stream is finished too, return SUCCESS so + * we'll iterate one more time. + */ + if (APR_STATUS_IS_EOF(status)) { + /* No more data to read from the stream, and everything + inflated. If all data was received correctly, state + should have been advanced to STATE_READING_VERIFY or + STATE_FINISH. If not, then the data was incomplete + and we have an error. */ + if (ctx->state != STATE_INFLATE) + return APR_SUCCESS; + else + return SERF_ERROR_DECOMPRESSION_FAILED; + } + } + return status; + case STATE_DONE: + /* We're done inflating. Use our finished buffer. */ + return serf_bucket_read(ctx->stream, requested, data, len); + default: + /* Not reachable */ + return APR_EGENERAL; + } + } + + /* NOTREACHED */ +} + +/* ### need to implement */ +#define serf_deflate_readline NULL +#define serf_deflate_peek NULL + +const serf_bucket_type_t serf_bucket_type_deflate = { + "DEFLATE", + serf_deflate_read, + serf_deflate_readline, + serf_default_read_iovec, + serf_default_read_for_sendfile, + serf_default_read_bucket, + serf_deflate_peek, + serf_deflate_destroy_and_data, +}; |