void XzCompress::Encode(void) { direct = 0; // set direction needed by parent [Get|Send]Chars() // get buffer char chunk[1024]; char *buf = (char *)calloc(1, 1024); char *chunkbuf = buf; unsigned long chunklen; unsigned long len = 0; while((chunklen = GetChars(chunk, 1023))) { memcpy(chunkbuf, chunk, chunklen); len += chunklen; if (chunklen < 1023) break; else buf = (char *)realloc(buf, len + 1024); chunkbuf = buf+len; } zlen = (long) (len*1.001)+15; // TODO: check that this is sufficient char *zbuf = new char[zlen+1]; size_t zpos = 0; if (len) { //printf("Doing compress\n"); if (lzma_block_buffer_encode(&block, NULL, (const uint8_t*)buf, (size_t)len, (uint8_t*)zbuf, &zpos, (size_t)zlen) != LZMA_OK) { printf("ERROR in compression\n"); } else { SendChars(zbuf, zlen); } } else { fprintf(stderr, "ERROR: no buffer to compress\n"); } delete [] zbuf; free (buf); }
lzma_stream_buffer_encode(lzma_filter *filters, lzma_check check, lzma_allocator *allocator, const uint8_t *in, size_t in_size, uint8_t *out, size_t *out_pos_ptr, size_t out_size) { // Sanity checks if (filters == NULL || (unsigned int)(check) > LZMA_CHECK_ID_MAX || (in == NULL && in_size != 0) || out == NULL || out_pos_ptr == NULL || *out_pos_ptr > out_size) return LZMA_PROG_ERROR; if (!lzma_check_is_supported(check)) return LZMA_UNSUPPORTED_CHECK; // Note for the paranoids: Index encoder prevents the Stream from // getting too big and still being accepted with LZMA_OK, and Block // encoder catches if the input is too big. So we don't need to // separately check if the buffers are too big. // Use a local copy. We update *out_pos_ptr only if everything // succeeds. size_t out_pos = *out_pos_ptr; // Check that there's enough space for both Stream Header and // Stream Footer. if (out_size - out_pos <= 2 * LZMA_STREAM_HEADER_SIZE) return LZMA_BUF_ERROR; // Reserve space for Stream Footer so we don't need to check for // available space again before encoding Stream Footer. out_size -= LZMA_STREAM_HEADER_SIZE; // Encode the Stream Header. lzma_stream_flags stream_flags = { .version = 0, .check = check, }; if (lzma_stream_header_encode(&stream_flags, out + out_pos) != LZMA_OK) return LZMA_PROG_ERROR; out_pos += LZMA_STREAM_HEADER_SIZE; // Encode a Block but only if there is at least one byte of input. lzma_block block = { .version = 0, .check = check, .filters = filters, }; if (in_size > 0) return_if_error(lzma_block_buffer_encode(&block, allocator, in, in_size, out, &out_pos, out_size)); // Index { // Create an Index. It will have one Record if there was // at least one byte of input to encode. Otherwise the // Index will be empty. lzma_index *i = lzma_index_init(allocator); if (i == NULL) return LZMA_MEM_ERROR; lzma_ret ret = LZMA_OK; if (in_size > 0) ret = lzma_index_append(i, allocator, lzma_block_unpadded_size(&block), block.uncompressed_size); // If adding the Record was successful, encode the Index // and get its size which will be stored into Stream Footer. if (ret == LZMA_OK) { ret = lzma_index_buffer_encode( i, out, &out_pos, out_size); stream_flags.backward_size = lzma_index_size(i); } lzma_index_end(i, allocator); if (ret != LZMA_OK) return ret; } // Stream Footer. We have already reserved space for this. if (lzma_stream_footer_encode(&stream_flags, out + out_pos) != LZMA_OK) return LZMA_PROG_ERROR; out_pos += LZMA_STREAM_HEADER_SIZE; // Everything went fine, make the new output position available // to the application. *out_pos_ptr = out_pos; return LZMA_OK; }