コード例 #1
0
ファイル: parse-zip.c プロジェクト: kepazon/my_sumatrapdf
bool zip_seek_to_compressed_data(ar_archive_zip *zip)
{
    struct zip_entry entry;

    if (!ar_seek(zip->super.stream, zip->entry.offset, SEEK_SET))
        return false;
    if (!zip_parse_local_file_entry(zip, &entry))
        return false;
    if (zip->entry.method != entry.method) {
        warn("Compression methods don't match: %d != %d", zip->entry.method, entry.method);
        if (!zip->entry.method)
            zip->entry.method = entry.method;
    }
    if (zip->entry.dosdate != entry.dosdate) {
        warn("Timestamps don't match");
        if (!zip->entry.dosdate) {
            zip->entry.dosdate = entry.dosdate;
            zip->super.entry_filetime = ar_conv_dosdate_to_filetime(zip->entry.dosdate);
        }
    }

    return ar_seek(zip->super.stream, zip->entry.offset + ZIP_LOCAL_ENTRY_FIXED_SIZE + entry.namelen + entry.extralen, SEEK_SET);
}
コード例 #2
0
ファイル: rar.c プロジェクト: jra101/sumatrapdf
static bool rar_parse_entry(ar_archive *ar, off64_t offset)
{
    ar_archive_rar *rar = (ar_archive_rar *)ar;
    struct rar_header header;
    struct rar_entry entry;
    bool out_of_order = offset != ar->entry_offset_next;

    if (!ar_seek(ar->stream, offset, SEEK_SET)) {
        warn("Couldn't seek to offset %" PRIi64, offset);
        return false;
    }

    for (;;) {
        ar->entry_offset = ar_tell(ar->stream);
        ar->entry_size_uncompressed = 0;

        if (!rar_parse_header(ar, &header))
            return false;

        ar->entry_offset_next = ar->entry_offset + header.size + header.datasize;
        if (ar->entry_offset_next < ar->entry_offset + header.size) {
            warn("Integer overflow due to overly large data size");
            return false;
        }

        switch (header.type) {
        case TYPE_MAIN_HEADER:
            if ((header.flags & MHD_PASSWORD)) {
                warn("Encrypted archives aren't supported");
                return false;
            }
            ar_skip(ar->stream, 6 /* reserved data */);
            if ((header.flags & MHD_ENCRYPTVER)) {
                log("MHD_ENCRYPTVER is set");
                ar_skip(ar->stream, 1);
            }
            if ((header.flags & MHD_COMMENT))
                log("MHD_COMMENT is set");
            if (ar_tell(ar->stream) - ar->entry_offset > header.size) {
                warn("Invalid RAR header size: %d", header.size);
                return false;
            }
            rar->archive_flags = header.flags;
            break;

        case TYPE_FILE_ENTRY:
            if (!rar_parse_header_entry(rar, &header, &entry))
                return false;
            if ((header.flags & LHD_PASSWORD))
                warn("Encrypted entries will fail to uncompress");
            if ((header.flags & LHD_DIRECTORY) == LHD_DIRECTORY) {
                if (header.datasize == 0) {
                    log("Skipping directory entry \"%s\"", rar_get_name(ar));
                    break;
                }
                warn("Can't skip directory entries containing data");
            }
            if ((header.flags & (LHD_SPLIT_BEFORE | LHD_SPLIT_AFTER)))
                warn("Splitting files isn't really supported");
            ar->entry_size_uncompressed = (size_t)entry.size;
            ar->entry_filetime = ar_conv_dosdate_to_filetime(entry.dosdate);
            if (!rar->entry.solid || rar->entry.method == METHOD_STORE || out_of_order) {
                rar_clear_uncompress(&rar->uncomp);
                memset(&rar->solid, 0, sizeof(rar->solid));
            }
            else {
                br_clear_leftover_bits(&rar->uncomp);
            }

            rar->solid.restart = rar->entry.solid && (out_of_order || !rar->solid.part_done);
            rar->solid.part_done = !ar->entry_size_uncompressed;
            rar->progress.data_left = (size_t)header.datasize;
            rar->progress.bytes_done = 0;
            rar->progress.crc = 0;

            /* TODO: CRC checks don't always hold (claim in XADRARParser.m @readBlockHeader) */
            if (!rar_check_header_crc(ar))
                warn("Invalid header checksum @%" PRIi64, ar->entry_offset);
            if (ar_tell(ar->stream) != ar->entry_offset + rar->entry.header_size) {
                warn("Couldn't seek to offset %" PRIi64, ar->entry_offset + rar->entry.header_size);
                return false;
            }
            return true;

        case TYPE_NEWSUB:
            log("Skipping newsub header @%" PRIi64, ar->entry_offset);
            break;

        case TYPE_END_OF_ARCHIVE:
            ar->at_eof = true;
            return false;

        default:
            log("Unknown RAR header type %02x", header.type);
            break;
        }

        /* TODO: CRC checks don't always hold (claim in XADRARParser.m @readBlockHeader) */
        if (!rar_check_header_crc(ar))
            warn("Invalid header checksum @%" PRIi64, ar->entry_offset);
        if (!ar_seek(ar->stream, ar->entry_offset_next, SEEK_SET)) {
            warn("Couldn't seek to offset %" PRIi64, ar->entry_offset_next);
            return false;
        }
    }
}