src/cmd/bzip2/lib/bzzlib.c - plan9 - Git at Google

 /*
  * THIS FILE IS NOT IDENTICAL TO THE ORIGINAL
  * FROM THE BZIP2 DISTRIBUTION.
  *
  * It has been modified, mainly to break the library
  * into smaller pieces.
  *
  * Russ Cox
  * rsc@plan9.bell-labs.com
  * July 2000
  */

 /*-------------------------------------------------------------*/
 /*--- Library top-level functions.                          ---*/
 /*---                                               bzlib.c ---*/
 /*-------------------------------------------------------------*/

 /*--
   This file is a part of bzip2 and/or libbzip2, a program and
   library for lossless, block-sorting data compression.

   Copyright (C) 1996-2000 Julian R Seward.  All rights reserved.

   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions
   are met:

   1. Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.

   2. The origin of this software must not be misrepresented; you must
      not claim that you wrote the original software.  If you use this
      software in a product, an acknowledgment in the product
      documentation would be appreciated but is not required.

   3. Altered source versions must be plainly marked as such, and must
      not be misrepresented as being the original software.

   4. The name of the author may not be used to endorse or promote
      products derived from this software without specific prior written
      permission.

   THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
   OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
   WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
   DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

   Julian Seward, Cambridge, UK.
   jseward@acm.org
   bzip2/libbzip2 version 1.0 of 21 March 2000

   This program is based on (at least) the work of:
      Mike Burrows
      David Wheeler
      Peter Fenwick
      Alistair Moffat
      Radford Neal
      Ian H. Witten
      Robert Sedgewick
      Jon L. Bentley

   For more information on these sources, see the manual.
 --*/

 /*--
    CHANGES
    ~~~~~~~
    0.9.0 -- original version.

    0.9.0a/b -- no changes in this file.

    0.9.0c
       * made zero-length BZ_FLUSH work correctly in bzCompress().
       * fixed bzWrite/bzRead to ignore zero-length requests.
       * fixed bzread to correctly handle read requests after EOF.
       * wrong parameter order in call to bzDecompressInit in
         bzBuffToBuffDecompress.  Fixed.
 --*/

 #include "os.h"
 #include "bzlib.h"
 #include "bzlib_private.h"
 #include "bzlib_stdio.h"
 #include "bzlib_stdio_private.h"

 /*---------------------------------------------------*/
 /*--
    Code contributed by Yoshioka Tsuneo
    (QWF00133@niftyserve.or.jp/tsuneo-y@is.aist-nara.ac.jp),
    to support better zlib compatibility.
    This code is not _officially_ part of libbzip2 (yet);
    I haven't tested it, documented it, or considered the
    threading-safeness of it.
    If this code breaks, please contact both Yoshioka and me.
 --*/
 /*---------------------------------------------------*/

 /*---------------------------------------------------*/

 #if defined(_WIN32) || defined(OS2) || defined(MSDOS)
 #   include <fcntl.h>
 #   include <io.h>
 #   define SET_BINARY_MODE(file) setmode(fileno(file),O_BINARY)
 #else
 #   define SET_BINARY_MODE(file)
 #endif
 static
 BZFILE * bzopen_or_bzdopen
                ( const char *path,   /* no use when bzdopen */
                  int fd,             /* no use when bzdopen */
                  const char *mode,
                  int open_mode)      /* bzopen: 0, bzdopen:1 */
 {
    int    bzerr;
    char   unused[BZ_MAX_UNUSED];
    int    blockSize100k = 9;
    int    writing       = 0;
    char   mode2[10]     = "";
    FILE   *fp           = NULL;
    BZFILE *bzfp         = NULL;
    int    verbosity     = 0;
    int    workFactor    = 30;
    int    smallMode     = 0;
    int    nUnused       = 0;

    if (mode == NULL) return NULL;
    while (*mode) {
       switch (*mode) {
       case 'r':
          writing = 0; break;
       case 'w':
          writing = 1; break;
       case 's':
          smallMode = 1; break;
       default:
          if (isdigit((int)(*mode))) {
             blockSize100k = *mode-'0';
          }
       }
       mode++;
    }
    strcat(mode2, writing ? "w" : "r" );
    strcat(mode2,"b");   /* binary mode */

    if (open_mode==0) {
       if (path==NULL || strcmp(path,"")==0) {
         fp = (writing ? stdout : stdin);
         SET_BINARY_MODE(fp);
       } else {
         fp = fopen(path,mode2);
       }
    } else {
 #ifdef BZ_STRICT_ANSI
       fp = NULL;
 #else
       fp = fdopen(fd,mode2);
 #endif
    }
    if (fp == NULL) return NULL;

    if (writing) {
       /* Guard against total chaos and anarchy -- JRS */
       if (blockSize100k < 1) blockSize100k = 1;
       if (blockSize100k > 9) blockSize100k = 9;
       bzfp = BZ2_bzWriteOpen(&bzerr,fp,blockSize100k,
                              verbosity,workFactor);
    } else {
       bzfp = BZ2_bzReadOpen(&bzerr,fp,verbosity,smallMode,
                             unused,nUnused);
    }
    if (bzfp == NULL) {
       if (fp != stdin && fp != stdout) fclose(fp);
       return NULL;
    }
    return bzfp;
 }


 /*---------------------------------------------------*/
 /*--
    open file for read or write.
       ex) bzopen("file","w9")
       case path="" or NULL => use stdin or stdout.
 --*/
 BZFILE * BZ_API(BZ2_bzopen)
                ( const char *path,
                  const char *mode )
 {
    return bzopen_or_bzdopen(path,-1,mode,/*bzopen*/0);
 }


 /*---------------------------------------------------*/
 BZFILE * BZ_API(BZ2_bzdopen)
                ( int fd,
                  const char *mode )
 {
    return bzopen_or_bzdopen(NULL,fd,mode,/*bzdopen*/1);
 }


 /*---------------------------------------------------*/
 int BZ_API(BZ2_bzread) (BZFILE* b, void* buf, int len )
 {
    int bzerr, nread;
    if (((bzFile*)b)->lastErr == BZ_STREAM_END) return 0;
    nread = BZ2_bzRead(&bzerr,b,buf,len);
    if (bzerr == BZ_OK || bzerr == BZ_STREAM_END) {
       return nread;
    } else {
       return -1;
    }
 }


 /*---------------------------------------------------*/
 int BZ_API(BZ2_bzwrite) (BZFILE* b, void* buf, int len )
 {
    int bzerr;

    BZ2_bzWrite(&bzerr,b,buf,len);
    if(bzerr == BZ_OK){
       return len;
    }else{
       return -1;
    }
 }


 /*---------------------------------------------------*/
 int BZ_API(BZ2_bzflush) (BZFILE *b)
 {
    /* do nothing now... */
    return 0;
 }


 /*---------------------------------------------------*/
 void BZ_API(BZ2_bzclose) (BZFILE* b)
 {
    int bzerr;
    FILE *fp = ((bzFile *)b)->handle;

    if (b==NULL) {return;}
    if(((bzFile*)b)->writing){
       BZ2_bzWriteClose(&bzerr,b,0,NULL,NULL);
       if(bzerr != BZ_OK){
          BZ2_bzWriteClose(NULL,b,1,NULL,NULL);
       }
    }else{
       BZ2_bzReadClose(&bzerr,b);
    }
    if(fp!=stdin && fp!=stdout){
       fclose(fp);
    }
 }


 /*---------------------------------------------------*/
 /*--
    return last error code
 --*/
 static char *bzerrorstrings[] = {
        "OK"
       ,"SEQUENCE_ERROR"
       ,"PARAM_ERROR"
       ,"MEM_ERROR"
       ,"DATA_ERROR"
       ,"DATA_ERROR_MAGIC"
       ,"IO_ERROR"
       ,"UNEXPECTED_EOF"
       ,"OUTBUFF_FULL"
       ,"CONFIG_ERROR"
       ,"???"   /* for future */
       ,"???"   /* for future */
       ,"???"   /* for future */
       ,"???"   /* for future */
       ,"???"   /* for future */
       ,"???"   /* for future */
 };


 const char * BZ_API(BZ2_bzerror) (BZFILE *b, int *errnum)
 {
    int err = ((bzFile *)b)->lastErr;

    if(err>0) err = 0;
    *errnum = err;
    return bzerrorstrings[err*-1];
 }
	/*
	* THIS FILE IS NOT IDENTICAL TO THE ORIGINAL
	* FROM THE BZIP2 DISTRIBUTION.
	*
	* It has been modified, mainly to break the library
	* into smaller pieces.
	*
	* Russ Cox
	* rsc@plan9.bell-labs.com
	* July 2000
	*/

	/-------------------------------------------------------------/
	/--- Library top-level functions. ---/
	/--- bzlib.c ---/
	/-------------------------------------------------------------/

	/*--
	This file is a part of bzip2 and/or libbzip2, a program and
	library for lossless, block-sorting data compression.

	Copyright (C) 1996-2000 Julian R Seward. All rights reserved.

	Redistribution and use in source and binary forms, with or without
	modification, are permitted provided that the following conditions
	are met:

	1. Redistributions of source code must retain the above copyright
	notice, this list of conditions and the following disclaimer.

	2. The origin of this software must not be misrepresented; you must
	not claim that you wrote the original software. If you use this
	software in a product, an acknowledgment in the product
	documentation would be appreciated but is not required.

	3. Altered source versions must be plainly marked as such, and must
	not be misrepresented as being the original software.

	4. The name of the author may not be used to endorse or promote
	products derived from this software without specific prior written
	permission.

	THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
	OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
	WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
	DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
	GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
	WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
	NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
	SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

	Julian Seward, Cambridge, UK.
	jseward@acm.org
	bzip2/libbzip2 version 1.0 of 21 March 2000

	This program is based on (at least) the work of:
	Mike Burrows
	David Wheeler
	Peter Fenwick
	Alistair Moffat
	Radford Neal
	Ian H. Witten
	Robert Sedgewick
	Jon L. Bentley

	For more information on these sources, see the manual.
	--*/

	/*--
	CHANGES
	~~~~~~~
	0.9.0 -- original version.

	0.9.0a/b -- no changes in this file.

	0.9.0c
	* made zero-length BZ_FLUSH work correctly in bzCompress().
	* fixed bzWrite/bzRead to ignore zero-length requests.
	* fixed bzread to correctly handle read requests after EOF.
	* wrong parameter order in call to bzDecompressInit in
	bzBuffToBuffDecompress. Fixed.
	--*/

	#include "os.h"
	#include "bzlib.h"
	#include "bzlib_private.h"
	#include "bzlib_stdio.h"
	#include "bzlib_stdio_private.h"

	/---------------------------------------------------/
	/*--
	Code contributed by Yoshioka Tsuneo
	(QWF00133@niftyserve.or.jp/tsuneo-y@is.aist-nara.ac.jp),
	to support better zlib compatibility.
	This code is not _officially_ part of libbzip2 (yet);
	I haven't tested it, documented it, or considered the
	threading-safeness of it.
	If this code breaks, please contact both Yoshioka and me.
	--*/
	/---------------------------------------------------/

	/---------------------------------------------------/

	#if defined(_WIN32) \|\| defined(OS2) \|\| defined(MSDOS)
	# include <fcntl.h>
	# include <io.h>
	# define SET_BINARY_MODE(file) setmode(fileno(file),O_BINARY)
	#else
	# define SET_BINARY_MODE(file)
	#endif
	static
	BZFILE * bzopen_or_bzdopen
	( const char path, / no use when bzdopen */
	int fd, /* no use when bzdopen */
	const char *mode,
	int open_mode) /* bzopen: 0, bzdopen:1 */
	{
	int bzerr;
	char unused[BZ_MAX_UNUSED];
	int blockSize100k = 9;
	int writing = 0;
	char mode2[10] = "";
	FILE *fp = NULL;
	BZFILE *bzfp = NULL;
	int verbosity = 0;
	int workFactor = 30;
	int smallMode = 0;
	int nUnused = 0;

	if (mode == NULL) return NULL;
	while (*mode) {
	switch (*mode) {
	case 'r':
	writing = 0; break;
	case 'w':
	writing = 1; break;
	case 's':
	smallMode = 1; break;
	default:
	if (isdigit((int)(*mode))) {
	blockSize100k = *mode-'0';
	}
	}
	mode++;
	}
	strcat(mode2, writing ? "w" : "r" );
	strcat(mode2,"b"); /* binary mode */

	if (open_mode==0) {
	if (path==NULL \|\| strcmp(path,"")==0) {
	fp = (writing ? stdout : stdin);
	SET_BINARY_MODE(fp);
	} else {
	fp = fopen(path,mode2);
	}
	} else {
	#ifdef BZ_STRICT_ANSI
	fp = NULL;
	#else
	fp = fdopen(fd,mode2);
	#endif
	}
	if (fp == NULL) return NULL;

	if (writing) {
	/* Guard against total chaos and anarchy -- JRS */
	if (blockSize100k < 1) blockSize100k = 1;
	if (blockSize100k > 9) blockSize100k = 9;
	bzfp = BZ2_bzWriteOpen(&bzerr,fp,blockSize100k,
	verbosity,workFactor);
	} else {
	bzfp = BZ2_bzReadOpen(&bzerr,fp,verbosity,smallMode,
	unused,nUnused);
	}
	if (bzfp == NULL) {
	if (fp != stdin && fp != stdout) fclose(fp);
	return NULL;
	}
	return bzfp;
	}


	/---------------------------------------------------/
	/*--
	open file for read or write.
	ex) bzopen("file","w9")
	case path="" or NULL => use stdin or stdout.
	--*/
	BZFILE * BZ_API(BZ2_bzopen)
	( const char *path,
	const char *mode )
	{
	return bzopen_or_bzdopen(path,-1,mode,/bzopen/0);
	}


	/---------------------------------------------------/
	BZFILE * BZ_API(BZ2_bzdopen)
	( int fd,
	const char *mode )
	{
	return bzopen_or_bzdopen(NULL,fd,mode,/bzdopen/1);
	}


	/---------------------------------------------------/
	int BZ_API(BZ2_bzread) (BZFILE* b, void* buf, int len )
	{
	int bzerr, nread;
	if (((bzFile*)b)->lastErr == BZ_STREAM_END) return 0;
	nread = BZ2_bzRead(&bzerr,b,buf,len);
	if (bzerr == BZ_OK \|\| bzerr == BZ_STREAM_END) {
	return nread;
	} else {
	return -1;
	}
	}


	/---------------------------------------------------/
	int BZ_API(BZ2_bzwrite) (BZFILE* b, void* buf, int len )
	{
	int bzerr;

	BZ2_bzWrite(&bzerr,b,buf,len);
	if(bzerr == BZ_OK){
	return len;
	}else{
	return -1;
	}
	}


	/---------------------------------------------------/
	int BZ_API(BZ2_bzflush) (BZFILE *b)
	{
	/* do nothing now... */
	return 0;
	}


	/---------------------------------------------------/
	void BZ_API(BZ2_bzclose) (BZFILE* b)
	{
	int bzerr;
	FILE fp = ((bzFile )b)->handle;

	if (b==NULL) {return;}
	if(((bzFile*)b)->writing){
	BZ2_bzWriteClose(&bzerr,b,0,NULL,NULL);
	if(bzerr != BZ_OK){
	BZ2_bzWriteClose(NULL,b,1,NULL,NULL);
	}
	}else{
	BZ2_bzReadClose(&bzerr,b);
	}
	if(fp!=stdin && fp!=stdout){
	fclose(fp);
	}
	}


	/---------------------------------------------------/
	/*--
	return last error code
	--*/
	static char *bzerrorstrings[] = {
	"OK"
	,"SEQUENCE_ERROR"
	,"PARAM_ERROR"
	,"MEM_ERROR"
	,"DATA_ERROR"
	,"DATA_ERROR_MAGIC"
	,"IO_ERROR"
	,"UNEXPECTED_EOF"
	,"OUTBUFF_FULL"
	,"CONFIG_ERROR"
	,"???" /* for future */
	,"???" /* for future */
	,"???" /* for future */
	,"???" /* for future */
	,"???" /* for future */
	,"???" /* for future */
	};


	const char * BZ_API(BZ2_bzerror) (BZFILE b, int errnum)
	{
	int err = ((bzFile *)b)->lastErr;

	if(err>0) err = 0;
	*errnum = err;
	return bzerrorstrings[err*-1];
	}