| /************************************************************** |
| * |
| * 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 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| * |
| *************************************************************/ |
| |
| |
| |
| #include "precompile.h" |
| |
| #include <stdio.h> |
| #include <string.h> |
| #include <stdlib.h> |
| #include <errno.h> |
| #include "hgzip.h" |
| #include "hstream.h" |
| |
| #ifndef local |
| # define local static |
| #endif |
| |
| #define Z_BUFSIZE (1024 * 4) |
| |
| #define ALLOC(size) malloc(size) |
| #define TRYFREE(p) {if (p) free(p);} |
| |
| #define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */ |
| #define HEAD_CRC 0x02 /* bit 1 set: header CRC present */ |
| #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ |
| #define ORIG_NAME 0x08 /* bit 3 set: original file name present */ |
| #define COMMENT 0x10 /* bit 4 set: file comment present */ |
| #define RESERVED 0xE0 /* bits 5..7: reserved */ |
| |
| local int get_byte(gz_stream * s); |
| local int destroy(gz_stream * s); |
| local 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 = (gz_stream *) ALLOC(sizeof(gz_stream)); |
| if (!s) |
| return Z_NULL; |
| s->stream.zalloc = (alloc_func) 0; |
| s->stream.zfree = (free_func) 0; |
| s->stream.opaque = (voidpf) 0; |
| s->stream.next_in = s->inbuf = Z_NULL; |
| s->stream.next_out = s->outbuf = 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(0L, Z_NULL, 0); |
| s->msg = NULL; |
| s->transparent = 0; |
| |
| s->mode = 'r'; |
| |
| //realking |
| err = inflateInit2(&(s->stream), -MAX_WBITS); |
| s->stream.next_in = s->inbuf = (Byte *) ALLOC(Z_BUFSIZE); |
| |
| if (err != Z_OK || s->inbuf == Z_NULL) |
| { |
| return destroy(s), (gz_stream *) Z_NULL; |
| } |
| |
| s->stream.avail_out = Z_BUFSIZE; |
| |
| errno = 0; |
| s->_inputstream = &_stream; |
| |
| return (gz_stream *) 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. |
| */ |
| local 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. |
| */ |
| local int destroy(gz_stream * s) |
| { |
| int err = Z_OK; |
| |
| if (!s) |
| return Z_STREAM_ERROR; |
| |
| TRYFREE(s->msg); |
| |
| if (s->stream.state != NULL) |
| { |
| err = inflateEnd(&(s->stream)); |
| } |
| if (s->z_err < 0) |
| err = s->z_err; |
| |
| TRYFREE(s->inbuf); |
| TRYFREE(s->outbuf); |
| TRYFREE(s); |
| return err; |
| } |
| |
| |
| // typedef unsigned char Byte |
| // typedef Byte FAR 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). |
| */ |
| int gz_read(gz_stream * file, voidp buf, unsigned len) |
| { |
| //printf("@@ gz_read : len : %d\t",len); |
| gz_stream *s = (gz_stream *) file; |
| Bytef *start = (Bytef *) buf; /* starting point for crc computation */ |
| Byte *next_out; /* == stream.next_out but not forced far (for MSDOS) */ |
| if (s == NULL) |
| return Z_STREAM_ERROR; |
| |
| if (s->z_err == Z_DATA_ERROR || s->z_err == Z_ERRNO) |
| return -1; |
| if (s->z_err == Z_STREAM_END) |
| return 0; /* EOF */ |
| |
| s->stream.next_out = next_out = (Bytef *) buf; |
| s->stream.avail_out = len; |
| |
| while (s->stream.avail_out != 0) |
| { |
| if (s->transparent) |
| { |
| /* Copy first the lookahead bytes: */ |
| uInt n = s->stream.avail_in; |
| |
| if (n > s->stream.avail_out) |
| n = s->stream.avail_out; |
| if (n > 0) |
| { |
| memcpy(s->stream.next_out, s->stream.next_in, n); |
| next_out += n; |
| s->stream.next_out = next_out; |
| s->stream.next_in += n; |
| s->stream.avail_out -= n; |
| s->stream.avail_in -= n; |
| } |
| if (s->stream.avail_out > 0) |
| { |
| s->stream.avail_out -= |
| s->_inputstream->readBytes(next_out, s->stream.avail_out); |
| } |
| return (int) (len - s->stream.avail_out); |
| } |
| 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, (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(0L, Z_NULL, 0); |
| } |
| } |
| if (s->z_err != Z_OK || s->z_eof) |
| break; |
| } |
| s->crc = crc32(s->crc, start, (uInt) (s->stream.next_out - start)); |
| return (int) (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; |
| int done = 0; |
| gz_stream *s = (gz_stream *) file; |
| |
| if (s == NULL || 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 = s->outbuf; |
| 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 |
| */ |
| local uLong getLong(gz_stream * s) |
| { |
| uLong x = (uLong) get_byte(s); |
| int c; |
| |
| x += ((uLong) get_byte(s)) << 8; |
| x += ((uLong) get_byte(s)) << 16; |
| c = get_byte(s); |
| if (c == EOF) |
| s->z_err = Z_DATA_ERROR; |
| x += ((uLong) c) << 24; |
| 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 = (gz_stream *) file; |
| |
| if (s == NULL) |
| 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); |
| } |