diff options
Diffstat (limited to 'hwpfilter/source/hgzip.cxx')
| -rw-r--r-- | hwpfilter/source/hgzip.cxx | 298 |
1 files changed, 298 insertions, 0 deletions
diff --git a/hwpfilter/source/hgzip.cxx b/hwpfilter/source/hgzip.cxx new file mode 100644 index 000000000..ed8ef8a75 --- /dev/null +++ b/hwpfilter/source/hgzip.cxx @@ -0,0 +1,298 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * This file is part of the LibreOffice project. + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. + * + * This file incorporates work covered by the following license notice: + * + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed + * with this work for additional information regarding copyright + * ownership. The ASF licenses this file to you 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 . + */ + +#include "precompile.h" + +#include <stdio.h> +#include <string.h> +#include <stdlib.h> +#include <errno.h> +#include "hgzip.h" +#include "hstream.hxx" + +#define Z_BUFSIZE (1024 * 4) + +#define ALLOC(size) malloc(size) +#define TRYFREE(p) {if (p) free(p);} + +static int get_byte(gz_stream * s); +static int destroy(gz_stream * s); +static uLong getLong(gz_stream * s); + +/* =========================================================================== + Opens a gzip (.gz) file for reading or writing. The mode parameter + is as in fopen ("rb" or "wb"). The file is given either by file descriptor + or path name (if fd == -1). + gz_open return NULL if the file could not be opened or if there was + insufficient memory to allocate the (de)compression state; errno + can be checked to distinguish the two cases (if errno is zero, the + zlib error is Z_MEM_ERROR). +*/ +gz_stream *gz_open(HStream & _stream) +{ + int err; + //int level = Z_DEFAULT_COMPRESSION; /* compression level */ + +// char *p = (char*)mode; + //char fmode[80]; /* copy of mode, without the compression level */ + //char *m = fmode; + gz_stream *s; + + s = static_cast<gz_stream *>(ALLOC(sizeof(gz_stream))); + if (!s) + return Z_NULL; + s->stream.zalloc = nullptr; + s->stream.zfree = nullptr; + s->stream.opaque = nullptr; + s->stream.next_in = s->inbuf = Z_NULL; + s->stream.next_out = Z_NULL; + s->stream.avail_in = s->stream.avail_out = 0; +//s->_inputstream = NULL; + s->z_err = Z_OK; + s->z_eof = 0; + s->crc = crc32(0, Z_NULL, 0); + s->msg = nullptr; + + s->mode = 'r'; + +//realking + err = inflateInit2(&(s->stream), -MAX_WBITS); + s->stream.next_in = s->inbuf = static_cast<Byte *>(ALLOC(Z_BUFSIZE)); + + if (err != Z_OK || s->inbuf == Z_NULL) + { + destroy(s); + return Z_NULL; + } + + s->stream.avail_out = Z_BUFSIZE; + + errno = 0; + s->_inputstream = &_stream; + + return s; +} + + +/* =========================================================================== + Read a byte from a gz_stream; update next_in and avail_in. Return EOF + for end of file. + IN assertion: the stream s has been successfully opened for reading. +*/ +static int get_byte(gz_stream * s) +{ + if (s->z_eof) + return EOF; + if (s->stream.avail_in == 0) + { + errno = 0; + + s->stream.avail_in = s->_inputstream->readBytes(s->inbuf, Z_BUFSIZE); + if (s->stream.avail_in == 0) + { + s->z_eof = 1; + return EOF; + } + s->stream.next_in = s->inbuf; + } + s->stream.avail_in--; + return *(s->stream.next_in)++; +} + + +/* =========================================================================== + * Cleanup then free the given gz_stream. Return a zlib error code. + * Try freeing in the reverse order of allocations. + */ +static int destroy(gz_stream * s) +{ + int err = Z_OK; + + if (!s) + return Z_STREAM_ERROR; + + TRYFREE(s->msg); + + if (s->stream.state != nullptr) + { + err = inflateEnd(&(s->stream)); + } + if (s->z_err < 0) + err = s->z_err; + + TRYFREE(s->inbuf); + TRYFREE(s); + return err; +} + + +// typedef unsigned char Byte +// typedef Byte Bytef; +/* =========================================================================== + Reads the given number of uncompressed bytes from the compressed file. + gz_read returns the number of bytes actually read (0 for end of file). +*/ +size_t gz_read(gz_stream * file, voidp buf, unsigned len) +{ +//printf("@@ gz_read : len : %d\t",len); + gz_stream *s = file; + Bytef *start = static_cast<Bytef *>(buf); /* starting point for crc computation */ + if (s == nullptr) + return 0; + + if (s->z_eof) + return 0; + + if (s->z_err == Z_DATA_ERROR || s->z_err == Z_ERRNO) + return 0; + if (s->z_err == Z_STREAM_END) + return 0; /* EOF */ + + s->stream.next_out = static_cast<Bytef *>(buf); + s->stream.avail_out = len; + + while (s->stream.avail_out != 0) + { + if (s->stream.avail_in == 0 && !s->z_eof) + { + + errno = 0; + s->stream.avail_in = s->_inputstream->readBytes(s->inbuf, Z_BUFSIZE); + if (s->stream.avail_in == 0) + { + s->z_eof = 1; + break; + } + s->stream.next_in = s->inbuf; + } + s->z_err = inflate(&(s->stream), Z_NO_FLUSH); + + if (s->z_err == Z_STREAM_END) + { +/* Check CRC and original size */ + s->crc = crc32(s->crc, start, static_cast<uInt>(s->stream.next_out - start)); + start = s->stream.next_out; + + if (getLong(s) != s->crc || getLong(s) != s->stream.total_out) + { + s->z_err = Z_DATA_ERROR; + } + else if (s->z_err == Z_OK) + { + inflateReset(&(s->stream)); + s->crc = crc32(0, Z_NULL, 0); + } + } + if (s->z_err != Z_OK || s->z_eof) + break; + } + s->crc = crc32(s->crc, start, static_cast<uInt>(s->stream.next_out - start)); + return len - s->stream.avail_out; +} + +/* =========================================================================== + Flushes all pending output into the compressed file. The parameter + flush is as in the deflate() function. + gz_flush should be called only when strictly necessary because it can + degrade compression. +*/ +int gz_flush(gz_stream * file, int flush) +{ + uInt len; + bool done = false; + gz_stream *s = file; + + if (s == nullptr || s->mode != 'w') + return Z_STREAM_ERROR; + + s->stream.avail_in = 0; /* should be zero already anyway */ + + for (;;) + { + len = Z_BUFSIZE - s->stream.avail_out; + if (len != 0) + { +/* + if ((uInt)fwrite(s->outbuf, 1, len, s->file) != len) { + s->z_err = Z_ERRNO; + return Z_ERRNO; + } + */ + s->stream.next_out = nullptr; + s->stream.avail_out = Z_BUFSIZE; + } + if (done) + break; + s->z_err = deflate(&(s->stream), flush); + +/* deflate has finished flushing only when it hasn't used up + * all the available space in the output buffer: + */ + done = (s->stream.avail_out != 0 || s->z_err == Z_STREAM_END); + + if (s->z_err != Z_OK && s->z_err != Z_STREAM_END) + break; + } + return s->z_err == Z_STREAM_END ? Z_OK : s->z_err; +} + + +/* =========================================================================== + Reads a long in LSB order from the given gz_stream. Sets +*/ +static uLong getLong(gz_stream * s) +{ + uLong x = static_cast<unsigned char>(get_byte(s)); + + x += static_cast<unsigned char>(get_byte(s)) << 8; + x += static_cast<unsigned char>(get_byte(s)) << 16; + x += static_cast<unsigned char>(get_byte(s)) << 24; + if (s->z_eof) + { + s->z_err = Z_DATA_ERROR; + } + return x; +} + + +/* =========================================================================== + Flushes all pending output if necessary, closes the compressed file + and deallocates all the (de)compression state. +*/ +int gz_close(gz_stream * file) +{ +// int err; + gz_stream *s = file; + + if (s == nullptr) + return Z_STREAM_ERROR; +#if 0 + if (s->mode == 'w') + { + err = gz_flush(file, Z_FINISH); + if (err != Z_OK) + return destroy(s); + putLong(s->file, s->crc); + putLong(s->file, s->stream.total_in); + } +#endif + return destroy(s); +} + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |