--- /dev/null
+/* Copyright (c) 2013-2014 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+
+#ifdef HAVE_LZ4
+
+#include "buffer.h"
+#include "istream-private.h"
+#include "istream-zlib.h"
+#include "iostream-lz4.h"
+#include <lz4.h>
+
+struct lz4_istream {
+ struct istream_private istream;
+
+ uoff_t stream_size;
+ struct stat last_parent_statbuf;
+
+ buffer_t *chunk_buf;
+ uint32_t chunk_size, chunk_left, max_uncompressed_chunk_size;
+
+ unsigned int log_errors:1;
+ unsigned int marked:1;
+ unsigned int header_read:1;
+};
+
+static void i_stream_lz4_close(struct iostream_private *stream,
+ bool close_parent)
+{
+ struct lz4_istream *zstream = (struct lz4_istream *)stream;
+
+ buffer_free(&zstream->chunk_buf);
+ if (close_parent)
+ i_stream_close(zstream->istream.parent);
+}
+
+static void lz4_read_error(struct lz4_istream *zstream, const char *error)
+{
+ io_stream_set_error(&zstream->istream.iostream,
+ "lz4.read(%s): %s at %"PRIuUOFF_T,
+ i_stream_get_name(&zstream->istream.istream), error,
+ zstream->istream.abs_start_offset +
+ zstream->istream.istream.v_offset);
+ if (zstream->log_errors)
+ i_error("%s", zstream->istream.iostream.error);
+}
+
+static int i_stream_lz4_read_header(struct lz4_istream *zstream)
+{
+ const struct iostream_lz4_header *hdr;
+ const unsigned char *data;
+ size_t size;
+ int ret;
+
+ ret = i_stream_read_data(zstream->istream.parent, &data, &size,
+ sizeof(*hdr)-1);
+ if (ret < 0) {
+ zstream->istream.istream.stream_errno =
+ zstream->istream.parent->stream_errno;
+ return ret;
+ }
+ if (ret == 0 && !zstream->istream.istream.eof)
+ return 0;
+ hdr = (const void *)data;
+ if (ret == 0 || memcmp(hdr->magic, IOSTREAM_LZ4_MAGIC,
+ IOSTREAM_LZ4_MAGIC_LEN) != 0) {
+ lz4_read_error(zstream, "wrong magic in header (not lz4 file?)");
+ zstream->istream.istream.stream_errno = EINVAL;
+ return -1;
+ }
+ zstream->max_uncompressed_chunk_size =
+ ((uint32_t)hdr->max_uncompressed_chunk_size[0] << 24) |
+ (hdr->max_uncompressed_chunk_size[1] << 16) |
+ (hdr->max_uncompressed_chunk_size[2] << 8) |
+ hdr->max_uncompressed_chunk_size[3];
+ if (zstream->max_uncompressed_chunk_size > ISTREAM_LZ4_CHUNK_SIZE) {
+ lz4_read_error(zstream, t_strdup_printf(
+ "lz4 max chunk size too large (%u > %u)",
+ zstream->max_uncompressed_chunk_size,
+ ISTREAM_LZ4_CHUNK_SIZE));
+ zstream->istream.istream.stream_errno = EINVAL;
+ return -1;
+ }
+ i_stream_skip(zstream->istream.parent, sizeof(*hdr));
+ return 1;
+}
+
+static ssize_t i_stream_lz4_read(struct istream_private *stream)
+{
+ struct lz4_istream *zstream = (struct lz4_istream *)stream;
+ const unsigned char *data;
+ size_t size, max_size;
+ int ret;
+
+ if (!zstream->header_read) {
+ if ((ret = i_stream_lz4_read_header(zstream)) <= 0)
+ return ret;
+ zstream->header_read = TRUE;
+ }
+
+ if (zstream->chunk_left == 0) {
+ ret = i_stream_read_data(stream->parent, &data, &size,
+ IOSTREAM_LZ4_CHUNK_PREFIX_LEN);
+ if (ret < 0) {
+ stream->istream.stream_errno =
+ stream->parent->stream_errno;
+ if (stream->istream.stream_errno != 0) {
+ stream->istream.eof = TRUE;
+ zstream->stream_size = stream->istream.v_offset +
+ stream->pos - stream->skip;
+ }
+ return ret;
+ }
+ if (ret == 0 && !stream->istream.eof)
+ return 0;
+ zstream->chunk_size = zstream->chunk_left =
+ ((uint32_t)data[0] << 24) |
+ (data[1] << 16) | (data[2] << 8) | data[3];
+ if (zstream->chunk_size == 0 ||
+ zstream->chunk_size > ISTREAM_LZ4_CHUNK_SIZE) {
+ lz4_read_error(zstream, t_strdup_printf(
+ "invalid lz4 chunk size: %u", zstream->chunk_size));
+ stream->istream.stream_errno = EINVAL;
+ return -1;
+ }
+ i_stream_skip(stream->parent, IOSTREAM_LZ4_CHUNK_PREFIX_LEN);
+ buffer_set_used_size(zstream->chunk_buf, 0);
+ }
+
+ /* read the whole compressed chunk into memory */
+ while (zstream->chunk_left > 0 &&
+ (ret = i_stream_read_data(zstream->istream.parent,
+ &data, &size, 0)) > 0) {
+ if (size > zstream->chunk_left)
+ size = zstream->chunk_left;
+ buffer_append(zstream->chunk_buf, data, size);
+ i_stream_skip(zstream->istream.parent, size);
+ zstream->chunk_left -= size;
+ }
+ if (zstream->chunk_left > 0) {
+ if (ret == -1 && zstream->istream.parent->stream_errno == 0) {
+ lz4_read_error(zstream, "truncated lz4 chunk");
+ stream->istream.stream_errno = EINVAL;
+ return -1;
+ }
+ zstream->istream.istream.stream_errno =
+ zstream->istream.parent->stream_errno;
+ return ret;
+ }
+ /* if we already have max_buffer_size amount of data, fail here */
+ i_stream_compress(stream);
+ if (stream->pos >= stream->max_buffer_size)
+ return -2;
+ /* allocate enough space for the old data and the new
+ decompressed chunk. we don't know the original compressed size,
+ so just allocate the max amount of memory. */
+ max_size = stream->pos + zstream->max_uncompressed_chunk_size;
+ if (stream->buffer_size < max_size) {
+ stream->w_buffer = i_realloc(stream->w_buffer,
+ stream->buffer_size, max_size);
+ stream->buffer_size = max_size;
+ stream->buffer = stream->w_buffer;
+ }
+ ret = LZ4_decompress_safe(zstream->chunk_buf->data,
+ (void *)(stream->w_buffer + stream->pos),
+ zstream->chunk_buf->used,
+ stream->buffer_size - stream->pos);
+ i_assert(ret <= (int)zstream->max_uncompressed_chunk_size);
+ if (ret < 0) {
+ lz4_read_error(zstream, "corrupted lz4 chunk");
+ stream->istream.stream_errno = EINVAL;
+ return -1;
+ }
+ i_assert(ret > 0);
+ stream->pos += ret;
+ i_assert(stream->pos <= stream->buffer_size);
+ return ret;
+}
+
+static void i_stream_lz4_reset(struct lz4_istream *zstream)
+{
+ struct istream_private *stream = &zstream->istream;
+
+ i_stream_seek(stream->parent, stream->parent_start_offset);
+ zstream->header_read = FALSE;
+ zstream->chunk_size = zstream->chunk_left = 0;
+
+ stream->parent_expected_offset = stream->parent_start_offset;
+ stream->skip = stream->pos = 0;
+ stream->istream.v_offset = 0;
+}
+
+static void
+i_stream_lz4_seek(struct istream_private *stream, uoff_t v_offset, bool mark)
+{
+ struct lz4_istream *zstream = (struct lz4_istream *) stream;
+ uoff_t start_offset = stream->istream.v_offset - stream->skip;
+
+ if (v_offset < start_offset) {
+ /* have to seek backwards */
+ i_stream_lz4_reset(zstream);
+ start_offset = 0;
+ }
+
+ if (v_offset <= start_offset + stream->pos) {
+ /* seeking backwards within what's already cached */
+ stream->skip = v_offset - start_offset;
+ stream->istream.v_offset = v_offset;
+ stream->pos = stream->skip;
+ } else {
+ /* read and cache forward */
+ do {
+ size_t avail = stream->pos - stream->skip;
+
+ if (stream->istream.v_offset + avail >= v_offset) {
+ i_stream_skip(&stream->istream,
+ v_offset -
+ stream->istream.v_offset);
+ break;
+ }
+
+ i_stream_skip(&stream->istream, avail);
+ } while (i_stream_read(&stream->istream) >= 0);
+
+ if (stream->istream.v_offset != v_offset) {
+ /* some failure, we've broken it */
+ if (stream->istream.stream_errno != 0) {
+ i_error("lz4_istream.seek(%s) failed: %s",
+ i_stream_get_name(&stream->istream),
+ strerror(stream->istream.stream_errno));
+ i_stream_close(&stream->istream);
+ } else {
+ /* unexpected EOF. allow it since we may just
+ want to check if there's anything.. */
+ i_assert(stream->istream.eof);
+ }
+ }
+ }
+
+ if (mark)
+ zstream->marked = TRUE;
+}
+
+static int
+i_stream_lz4_stat(struct istream_private *stream, bool exact)
+{
+ struct lz4_istream *zstream = (struct lz4_istream *) stream;
+ const struct stat *st;
+ size_t size;
+
+ if (i_stream_stat(stream->parent, exact, &st) < 0)
+ return -1;
+ stream->statbuf = *st;
+
+ /* when exact=FALSE always return the parent stat's size, even if we
+ know the exact value. this is necessary because otherwise e.g. mbox
+ code can see two different values and think that a compressed mbox
+ file keeps changing. */
+ if (!exact)
+ return 0;
+
+ if (zstream->stream_size == (uoff_t)-1) {
+ uoff_t old_offset = stream->istream.v_offset;
+
+ do {
+ size = i_stream_get_data_size(&stream->istream);
+ i_stream_skip(&stream->istream, size);
+ } while (i_stream_read(&stream->istream) > 0);
+
+ i_stream_seek(&stream->istream, old_offset);
+ if (zstream->stream_size == (uoff_t)-1)
+ return -1;
+ }
+ stream->statbuf.st_size = zstream->stream_size;
+ return 0;
+}
+
+static void i_stream_lz4_sync(struct istream_private *stream)
+{
+ struct lz4_istream *zstream = (struct lz4_istream *) stream;
+ const struct stat *st;
+
+ if (i_stream_stat(stream->parent, FALSE, &st) < 0) {
+ if (memcmp(&zstream->last_parent_statbuf,
+ st, sizeof(*st)) == 0) {
+ /* a compressed file doesn't change unexpectedly,
+ don't clear our caches unnecessarily */
+ return;
+ }
+ zstream->last_parent_statbuf = *st;
+ }
+ i_stream_lz4_reset(zstream);
+}
+
+struct istream *i_stream_create_lz4(struct istream *input, bool log_errors)
+{
+ struct lz4_istream *zstream;
+
+ zstream = i_new(struct lz4_istream, 1);
+ zstream->stream_size = (uoff_t)-1;
+ zstream->log_errors = log_errors;
+
+ zstream->istream.iostream.close = i_stream_lz4_close;
+ zstream->istream.max_buffer_size = input->real_stream->max_buffer_size;
+ zstream->istream.read = i_stream_lz4_read;
+ zstream->istream.seek = i_stream_lz4_seek;
+ zstream->istream.stat = i_stream_lz4_stat;
+ zstream->istream.sync = i_stream_lz4_sync;
+
+ zstream->istream.istream.readable_fd = FALSE;
+ zstream->istream.istream.blocking = input->blocking;
+ zstream->istream.istream.seekable = input->seekable;
+ zstream->chunk_buf = buffer_create_dynamic(default_pool, 1024);
+
+ return i_stream_create(&zstream->istream, input,
+ i_stream_get_fd(input));
+}
+#endif
--- /dev/null
+/* Copyright (c) 2013-2014 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+
+#ifdef HAVE_LZ4
+
+#include "ostream-private.h"
+#include "ostream-zlib.h"
+#include "iostream-lz4.h"
+#include <lz4.h>
+
+#define CHUNK_SIZE OSTREAM_LZ4_CHUNK_SIZE
+
+struct lz4_ostream {
+ struct ostream_private ostream;
+
+ unsigned char compressbuf[CHUNK_SIZE];
+ unsigned int compressbuf_offset;
+
+ /* chunk size, followed by compressed data */
+ unsigned char outbuf[IOSTREAM_LZ4_CHUNK_PREFIX_LEN + CHUNK_SIZE];
+ unsigned int outbuf_offset, outbuf_used;
+};
+
+static void o_stream_lz4_close(struct iostream_private *stream,
+ bool close_parent)
+{
+ struct lz4_ostream *zstream = (struct lz4_ostream *)stream;
+
+ (void)o_stream_flush(&zstream->ostream.ostream);
+ if (close_parent)
+ o_stream_close(zstream->ostream.parent);
+}
+
+static int o_stream_lz4_send_outbuf(struct lz4_ostream *zstream)
+{
+ ssize_t ret;
+ size_t size;
+
+ if (zstream->outbuf_used == 0)
+ return 1;
+
+ size = zstream->outbuf_used - zstream->outbuf_offset;
+ i_assert(size > 0);
+ ret = o_stream_send(zstream->ostream.parent,
+ zstream->outbuf + zstream->outbuf_offset, size);
+ if (ret < 0) {
+ o_stream_copy_error_from_parent(&zstream->ostream);
+ return -1;
+ }
+ if ((size_t)ret != size) {
+ zstream->outbuf_offset += ret;
+ return 0;
+ }
+ zstream->outbuf_offset = 0;
+ zstream->outbuf_used = 0;
+ return 1;
+}
+
+static int o_stream_lz4_compress(struct lz4_ostream *zstream)
+{
+ uint32_t chunk_size;
+ int ret;
+
+ if (zstream->compressbuf_offset == 0)
+ return 1;
+ if ((ret = o_stream_lz4_send_outbuf(zstream)) <= 0)
+ return ret;
+
+ i_assert(zstream->outbuf_offset == 0);
+ i_assert(zstream->outbuf_used == 0);
+
+ zstream->outbuf_used = IOSTREAM_LZ4_CHUNK_PREFIX_LEN +
+ LZ4_compress((void *)zstream->compressbuf,
+ (void *)(zstream->outbuf + IOSTREAM_LZ4_CHUNK_PREFIX_LEN),
+ zstream->compressbuf_offset);
+ i_assert(zstream->outbuf_used > IOSTREAM_LZ4_CHUNK_PREFIX_LEN);
+ chunk_size = zstream->outbuf_used - IOSTREAM_LZ4_CHUNK_PREFIX_LEN;
+ zstream->outbuf[0] = (chunk_size & 0xff000000) >> 24;
+ zstream->outbuf[1] = (chunk_size & 0x00ff0000) >> 16;
+ zstream->outbuf[2] = (chunk_size & 0x0000ff00) >> 8;
+ zstream->outbuf[3] = (chunk_size & 0x000000ff);
+ zstream->compressbuf_offset = 0;
+ return 1;
+}
+
+static ssize_t
+o_stream_lz4_send_chunk(struct lz4_ostream *zstream,
+ const void *data, size_t size)
+{
+ size_t max_size;
+ ssize_t added_bytes = 0;
+ int ret;
+
+ i_assert(zstream->outbuf_used == 0);
+
+ do {
+ max_size = I_MIN(size, sizeof(zstream->compressbuf) -
+ zstream->compressbuf_offset);
+ memcpy(zstream->compressbuf + zstream->compressbuf_offset,
+ data, max_size);
+ zstream->compressbuf_offset += max_size;
+
+ data = CONST_PTR_OFFSET(data, max_size);
+ size -= max_size;
+ added_bytes += max_size;
+
+ if (zstream->compressbuf_offset == sizeof(zstream->compressbuf)) {
+ ret = o_stream_lz4_compress(zstream);
+ if (ret <= 0)
+ return added_bytes != 0 ? added_bytes : ret;
+ }
+ } while (size > 0);
+
+ return added_bytes;
+}
+
+static int o_stream_lz4_flush(struct ostream_private *stream)
+{
+ struct lz4_ostream *zstream = (struct lz4_ostream *)stream;
+ int ret;
+
+ if (o_stream_lz4_compress(zstream) < 0)
+ return -1;
+ if (o_stream_lz4_send_outbuf(zstream) < 0)
+ return -1;
+
+ ret = o_stream_flush(stream->parent);
+ if (ret < 0)
+ o_stream_copy_error_from_parent(stream);
+ return ret;
+}
+
+static ssize_t
+o_stream_lz4_sendv(struct ostream_private *stream,
+ const struct const_iovec *iov, unsigned int iov_count)
+{
+ struct lz4_ostream *zstream = (struct lz4_ostream *)stream;
+ ssize_t ret, bytes = 0;
+ unsigned int i;
+
+ if ((ret = o_stream_lz4_send_outbuf(zstream)) <= 0) {
+ /* error / we still couldn't flush existing data to
+ parent stream. */
+ return ret;
+ }
+
+ for (i = 0; i < iov_count; i++) {
+ ret = o_stream_lz4_send_chunk(zstream, iov[i].iov_base,
+ iov[i].iov_len);
+ if (ret < 0)
+ return -1;
+ bytes += ret;
+ if ((size_t)ret != iov[i].iov_len)
+ break;
+ }
+ stream->ostream.offset += bytes;
+ return bytes;
+}
+
+struct ostream *o_stream_create_lz4(struct ostream *output, int level)
+{
+ struct iostream_lz4_header *hdr;
+ struct lz4_ostream *zstream;
+
+ i_assert(level >= 1 && level <= 9);
+
+ zstream = i_new(struct lz4_ostream, 1);
+ zstream->ostream.sendv = o_stream_lz4_sendv;
+ zstream->ostream.flush = o_stream_lz4_flush;
+ zstream->ostream.iostream.close = o_stream_lz4_close;
+
+ i_assert(sizeof(zstream->outbuf) >= sizeof(*hdr));
+ hdr = (void *)zstream->outbuf;
+ memcpy(hdr->magic, IOSTREAM_LZ4_MAGIC, sizeof(hdr->magic));
+ hdr->max_uncompressed_chunk_size[0] =
+ (OSTREAM_LZ4_CHUNK_SIZE & 0xff000000) >> 24;
+ hdr->max_uncompressed_chunk_size[1] =
+ (OSTREAM_LZ4_CHUNK_SIZE & 0x00ff0000) >> 16;
+ hdr->max_uncompressed_chunk_size[2] =
+ (OSTREAM_LZ4_CHUNK_SIZE & 0x0000ff00) >> 8;
+ hdr->max_uncompressed_chunk_size[3] =
+ (OSTREAM_LZ4_CHUNK_SIZE & 0x000000ff);
+ zstream->outbuf_used = sizeof(*hdr);
+ return o_stream_create(&zstream->ostream, output,
+ o_stream_get_fd(output));
+}
+#endif
projects / thirdparty / dovecot / core.git / commitdiff
