src/lib-compression/istream-lzma.c

bcb4e51a409d94ae670de96afb8483a4f7855294Stephan Bosch/* Copyright (c) 2010-2018 Dovecot authors, see the included COPYING file */
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen#include "lib.h"
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen#ifdef HAVE_LZMA
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen#include "istream-private.h"
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen#include "istream-zlib.h"
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen#include <lzma.h>
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen#define CHUNK_SIZE (1024*64)
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen#define LZMA_MEMORY_LIMIT (1024*1024*80)
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainenstruct lzma_istream {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    struct istream_private istream;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    lzma_stream strm;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    uoff_t eof_offset, stream_size;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    size_t high_pos;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    struct stat last_parent_statbuf;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
0dffa25d211be541ee3c953b23566a1a990789dfTimo Sirainen    bool log_errors:1;
0dffa25d211be541ee3c953b23566a1a990789dfTimo Sirainen    bool marked:1;
0dffa25d211be541ee3c953b23566a1a990789dfTimo Sirainen    bool strm_closed:1;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen};
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainenstatic void i_stream_lzma_close(struct iostream_private *stream,
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                 bool close_parent)
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen{
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    struct lzma_istream *zstream = (struct lzma_istream *)stream;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    if (!zstream->strm_closed) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        lzma_end(&zstream->strm);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        zstream->strm_closed = TRUE;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    if (close_parent)
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        i_stream_close(zstream->istream.parent);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen}
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainenstatic void lzma_read_error(struct lzma_istream *zstream, const char *error)
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen{
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    io_stream_set_error(&zstream->istream.iostream,
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                "lzma.read(%s): %s at %"PRIuUOFF_T,
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                i_stream_get_name(&zstream->istream.istream), error,
d28179fd78550a58be44dcb1e3e830ab7d33172dTimo Sirainen                i_stream_get_absolute_offset(&zstream->istream.istream));
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    if (zstream->log_errors)
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        i_error("%s", zstream->istream.iostream.error);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen}
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
62c05ba0290a0bf9c2b0ab4ce117f9a736907c21Timo Sirainenstatic void lzma_stream_end(struct lzma_istream *zstream)
62c05ba0290a0bf9c2b0ab4ce117f9a736907c21Timo Sirainen{
62c05ba0290a0bf9c2b0ab4ce117f9a736907c21Timo Sirainen    zstream->eof_offset = zstream->istream.istream.v_offset +
62c05ba0290a0bf9c2b0ab4ce117f9a736907c21Timo Sirainen        (zstream->istream.pos - zstream->istream.skip);
62c05ba0290a0bf9c2b0ab4ce117f9a736907c21Timo Sirainen    zstream->stream_size = zstream->eof_offset;
62c05ba0290a0bf9c2b0ab4ce117f9a736907c21Timo Sirainen}
62c05ba0290a0bf9c2b0ab4ce117f9a736907c21Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainenstatic ssize_t i_stream_lzma_read(struct istream_private *stream)
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen{
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    struct lzma_istream *zstream = (struct lzma_istream *)stream;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    const unsigned char *data;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    uoff_t high_offset;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    size_t size, out_size;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    lzma_ret ret;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    high_offset = stream->istream.v_offset + (stream->pos - stream->skip);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    if (zstream->eof_offset == high_offset) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        i_assert(zstream->high_pos == 0 ||
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen             zstream->high_pos == stream->pos);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        stream->istream.eof = TRUE;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        return -1;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    if (stream->pos < zstream->high_pos) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        /* we're here because we seeked back within the read buffer. */
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        ret = zstream->high_pos - stream->pos;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        stream->pos = zstream->high_pos;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        zstream->high_pos = 0;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        if (zstream->eof_offset != (uoff_t)-1) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            high_offset = stream->istream.v_offset +
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                (stream->pos - stream->skip);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            i_assert(zstream->eof_offset == high_offset);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            stream->istream.eof = TRUE;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        return ret;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->high_pos = 0;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
ef4661aec4031e24944175ab914dc60942a2b68aTimo Sirainen    if (!zstream->marked) {
ef4661aec4031e24944175ab914dc60942a2b68aTimo Sirainen        if (!i_stream_try_alloc(stream, CHUNK_SIZE, &out_size))
ef4661aec4031e24944175ab914dc60942a2b68aTimo Sirainen            return -2; /* buffer full */
ef4661aec4031e24944175ab914dc60942a2b68aTimo Sirainen    } else {
ef4661aec4031e24944175ab914dc60942a2b68aTimo Sirainen        /* try to avoid compressing, so we can quickly seek backwards */
ef4661aec4031e24944175ab914dc60942a2b68aTimo Sirainen        if (!i_stream_try_alloc_avoid_compress(stream, CHUNK_SIZE, &out_size))
ef4661aec4031e24944175ab914dc60942a2b68aTimo Sirainen            return -2; /* buffer full */
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
3858a7a5da361c35f1e6e50c8e3214dc0cf379d6Phil Carmody    if (i_stream_read_more(stream->parent, &data, &size) < 0) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        if (stream->parent->stream_errno != 0) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            stream->istream.stream_errno =
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                stream->parent->stream_errno;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        } else {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            i_assert(stream->parent->eof);
62c05ba0290a0bf9c2b0ab4ce117f9a736907c21Timo Sirainen            lzma_stream_end(zstream);
62c05ba0290a0bf9c2b0ab4ce117f9a736907c21Timo Sirainen            stream->istream.eof = TRUE;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        return -1;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    if (size == 0) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        /* no more input */
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        i_assert(!stream->istream.blocking);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        return 0;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->strm.next_in = data;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->strm.avail_in = size;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->strm.next_out = stream->w_buffer + stream->pos;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->strm.avail_out = out_size;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    ret = lzma_code(&zstream->strm, LZMA_RUN);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    out_size -= zstream->strm.avail_out;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    stream->pos += out_size;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    i_stream_skip(stream->parent, size - zstream->strm.avail_in);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    switch (ret) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    case LZMA_OK:
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        break;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    case LZMA_DATA_ERROR:
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    case LZMA_BUF_ERROR:
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        lzma_read_error(zstream, "corrupted data");
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        stream->istream.stream_errno = EINVAL;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        return -1;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    case LZMA_FORMAT_ERROR:
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        lzma_read_error(zstream, "wrong magic in header (not xz file?)");
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        stream->istream.stream_errno = EINVAL;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        return -1;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    case LZMA_OPTIONS_ERROR:
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        lzma_read_error(zstream, "Unsupported xz options");
ad31916e2ad230d0e553203a5461bf7a8dc0d816Timo Sirainen        stream->istream.stream_errno = EIO;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        return -1;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    case LZMA_MEM_ERROR:
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        i_fatal_status(FATAL_OUTOFMEM, "lzma.read(%s): Out of memory",
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                   i_stream_get_name(&stream->istream));
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    case LZMA_STREAM_END:
62c05ba0290a0bf9c2b0ab4ce117f9a736907c21Timo Sirainen        lzma_stream_end(zstream);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        if (out_size == 0) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            stream->istream.eof = TRUE;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            return -1;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        break;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    default:
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        lzma_read_error(zstream, t_strdup_printf(
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            "lzma_code() failed with %d", ret));
ad31916e2ad230d0e553203a5461bf7a8dc0d816Timo Sirainen        stream->istream.stream_errno = EIO;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        return -1;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    if (out_size == 0) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        /* read more input */
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        return i_stream_lzma_read(stream);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    return out_size;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen}
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainenstatic void i_stream_lzma_init(struct lzma_istream *zstream)
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen{
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    lzma_ret ret;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    ret = lzma_stream_decoder(&zstream->strm, LZMA_MEMORY_LIMIT,
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                  LZMA_CONCATENATED);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    switch (ret) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    case LZMA_OK:
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        break;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    case LZMA_MEM_ERROR:
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        i_fatal_status(FATAL_OUTOFMEM, "lzma: Out of memory");
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    default:
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        i_fatal("lzma_stream_decoder() failed with ret=%d", ret);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen}
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainenstatic void i_stream_lzma_reset(struct lzma_istream *zstream)
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen{
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    struct istream_private *stream = &zstream->istream;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    i_stream_seek(stream->parent, stream->parent_start_offset);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->eof_offset = (uoff_t)-1;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->strm.next_in = NULL;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->strm.avail_in = 0;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    stream->parent_expected_offset = stream->parent_start_offset;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    stream->skip = stream->pos = 0;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    stream->istream.v_offset = 0;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->high_pos = 0;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    lzma_end(&zstream->strm);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    i_stream_lzma_init(zstream);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen}
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainenstatic void
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Siraineni_stream_lzma_seek(struct istream_private *stream, uoff_t v_offset, bool mark)
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen{
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    struct lzma_istream *zstream = (struct lzma_istream *) stream;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    uoff_t start_offset = stream->istream.v_offset - stream->skip;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    if (v_offset < start_offset) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        /* have to seek backwards */
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        i_stream_lzma_reset(zstream);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        start_offset = 0;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    } else if (zstream->high_pos != 0) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        stream->pos = zstream->high_pos;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        zstream->high_pos = 0;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    if (v_offset <= start_offset + stream->pos) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        /* seeking backwards within what's already cached */
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        stream->skip = v_offset - start_offset;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        stream->istream.v_offset = v_offset;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        zstream->high_pos = stream->pos;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        stream->pos = stream->skip;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    } else {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        /* read and cache forward */
9dadffcd2545eab4b251e83b60cee78ceb1e8362Anton Yuzhaninov        ssize_t ret;
7f74811b78f8915e73dffc88bb49009e98b6846dTimo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        do {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            size_t avail = stream->pos - stream->skip;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            if (stream->istream.v_offset + avail >= v_offset) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                i_stream_skip(&stream->istream,
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                          v_offset -
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                          stream->istream.v_offset);
9dadffcd2545eab4b251e83b60cee78ceb1e8362Anton Yuzhaninov                ret = -1;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                break;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            i_stream_skip(&stream->istream, avail);
7f74811b78f8915e73dffc88bb49009e98b6846dTimo Sirainen        } while ((ret = i_stream_read(&stream->istream)) > 0);
7f74811b78f8915e73dffc88bb49009e98b6846dTimo Sirainen        i_assert(ret == -1);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        if (stream->istream.v_offset != v_offset) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            /* some failure, we've broken it */
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            if (stream->istream.stream_errno != 0) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                i_error("lzma_istream.seek(%s) failed: %s",
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                    i_stream_get_name(&stream->istream),
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                    strerror(stream->istream.stream_errno));
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                i_stream_close(&stream->istream);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            } else {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                /* unexpected EOF. allow it since we may just
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                   want to check if there's anything.. */
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen                i_assert(stream->istream.eof);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    if (mark)
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        zstream->marked = TRUE;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen}
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainenstatic int
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Siraineni_stream_lzma_stat(struct istream_private *stream, bool exact)
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen{
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    struct lzma_istream *zstream = (struct lzma_istream *) stream;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    const struct stat *st;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    size_t size;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
2c0f1cb7a0564d48ec43c7315ea46ea38d2abd19Timo Sirainen    if (i_stream_stat(stream->parent, exact, &st) < 0) {
2c0f1cb7a0564d48ec43c7315ea46ea38d2abd19Timo Sirainen        stream->istream.stream_errno = stream->parent->stream_errno;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        return -1;
2c0f1cb7a0564d48ec43c7315ea46ea38d2abd19Timo Sirainen    }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    stream->statbuf = *st;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    /* when exact=FALSE always return the parent stat's size, even if we
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen       know the exact value. this is necessary because otherwise e.g. mbox
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen       code can see two different values and think that a compressed mbox
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen       file keeps changing. */
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    if (!exact)
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        return 0;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    if (zstream->stream_size == (uoff_t)-1) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        uoff_t old_offset = stream->istream.v_offset;
7f74811b78f8915e73dffc88bb49009e98b6846dTimo Sirainen        ssize_t ret;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        do {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            size = i_stream_get_data_size(&stream->istream);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            i_stream_skip(&stream->istream, size);
7f74811b78f8915e73dffc88bb49009e98b6846dTimo Sirainen        } while ((ret = i_stream_read(&stream->istream)) > 0);
7f74811b78f8915e73dffc88bb49009e98b6846dTimo Sirainen        i_assert(ret == -1);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        i_stream_seek(&stream->istream, old_offset);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        if (zstream->stream_size == (uoff_t)-1)
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            return -1;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    stream->statbuf.st_size = zstream->stream_size;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    return 0;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen}
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainenstatic void i_stream_lzma_sync(struct istream_private *stream)
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen{
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    struct lzma_istream *zstream = (struct lzma_istream *) stream;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    const struct stat *st;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    if (i_stream_stat(stream->parent, FALSE, &st) < 0) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        if (memcmp(&zstream->last_parent_statbuf,
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen               st, sizeof(*st)) == 0) {
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            /* a compressed file doesn't change unexpectedly,
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen               don't clear our caches unnecessarily */
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen            return;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen        zstream->last_parent_statbuf = *st;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    }
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    i_stream_lzma_reset(zstream);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen}
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainenstruct istream *i_stream_create_lzma(struct istream *input, bool log_errors)
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen{
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    struct lzma_istream *zstream;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream = i_new(struct lzma_istream, 1);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->eof_offset = (uoff_t)-1;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->stream_size = (uoff_t)-1;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->log_errors = log_errors;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    i_stream_lzma_init(zstream);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->istream.iostream.close = i_stream_lzma_close;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->istream.max_buffer_size = input->real_stream->max_buffer_size;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->istream.read = i_stream_lzma_read;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->istream.seek = i_stream_lzma_seek;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->istream.stat = i_stream_lzma_stat;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->istream.sync = i_stream_lzma_sync;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->istream.istream.readable_fd = FALSE;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->istream.istream.blocking = input->blocking;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    zstream->istream.istream.seekable = input->seekable;
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen    return i_stream_create(&zstream->istream, input,
2974dca6be5120e49279f06c8aa952e5fac56048Timo Sirainen                   i_stream_get_fd(input), 0);
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen}
12983e9d3b4ebdfb1e14f197c153304b3af44b59Timo Sirainen#endif