zlib.c   [plain text]

/*
   +----------------------------------------------------------------------+
   | PHP Version 4                                                        |
   +----------------------------------------------------------------------+
   | Copyright (c) 1997-2007 The PHP Group                                |
   +----------------------------------------------------------------------+
   | This source file is subject to version 3.01 of the PHP license,      |
   | that is bundled with this package in the file LICENSE, and is        |
   | available through the world-wide-web at the following url:           |
   | http://www.php.net/license/3_01.txt                                  |
   | If you did not receive a copy of the PHP license and are unable to   |
   | obtain it through the world-wide-web, please send a note to          |
   | license@php.net so we can mail you a copy immediately.               |
   +----------------------------------------------------------------------+
   | Authors: Rasmus Lerdorf <rasmus@lerdorf.on.ca>                       |
   |          Stefan Röhrich <sr@linux.de>                                |
   |          Zeev Suraski <zeev@zend.com>                                |
   |          Jade Nicoletti <nicoletti@nns.ch>                           |
   +----------------------------------------------------------------------+
 */
/* $Id: zlib.c,v 1.153.2.16.4.4 2007/01/01 09:46:50 sebastian Exp $ */
#define IS_EXT_MODULE

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "php.h"
#include "SAPI.h"
#include "php_ini.h"

#include <stdlib.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#ifdef PHP_WIN32
#include <windows.h>
#include <winsock.h>
#define O_RDONLY _O_RDONLY
#include "win32/param.h"
#else
#include <sys/param.h>
/* #include <sys/uio.h> */
#endif
#include "ext/standard/head.h"
#include "safe_mode.h"
#include "ext/standard/php_standard.h"
#include "ext/standard/info.h"
#include "php_zlib.h"
#include "fopen_wrappers.h"
#if HAVE_PWD_H
#ifdef PHP_WIN32
#include "win32/pwd.h"
#else
#include <pwd.h>
#endif
#endif
#if defined(HAVE_UNISTD_H) && defined(PHP_WIN32)
#undef HAVE_UNISTD_H
#endif


#ifdef COMPILE_DL_ZLIB
#ifndef PUTS
#define PUTS(a) php_printf("%s",a)
#endif
#ifndef PUTC
#define PUTC(a) PUTS(a)
#endif
#ifndef PHPWRITE
#define PHPWRITE(a,n) php_write((a),(n) TSRMLS_CC)
#endif
#endif

#define OS_CODE			0x03 /* FIXME */
#define GZIP_HEADER_LENGTH		10
#define GZIP_FOOTER_LENGTH		8

/* True globals, no need for thread safety */
static int gz_magic[2] = {0x1f, 0x8b};	/* gzip magic header */

/* {{{ php_zlib_functions[]
 */
function_entry php_zlib_functions[] = {
	PHP_FE(readgzfile,						NULL)
	PHP_FALIAS(gzrewind,	rewind,			NULL)
	PHP_FALIAS(gzclose,		fclose,			NULL)
	PHP_FALIAS(gzeof,		feof,			NULL)
	PHP_FALIAS(gzgetc,		fgetc,			NULL)
	PHP_FALIAS(gzgets,		fgets,			NULL)
	PHP_FALIAS(gzgetss,		fgetss,			NULL)
	PHP_FALIAS(gzread,		fread,			NULL)
	PHP_FE(gzopen,							NULL)
	PHP_FALIAS(gzpassthru,	fpassthru,		NULL)
	PHP_FALIAS(gzseek,		fseek,			NULL)
	PHP_FALIAS(gztell,		ftell,			NULL)
	PHP_FALIAS(gzwrite,		fwrite,			NULL)
	PHP_FALIAS(gzputs,		fwrite,			NULL)
	PHP_FE(gzfile,							NULL)
	PHP_FE(gzcompress,            			NULL)
	PHP_FE(gzuncompress,           			NULL)
	PHP_FE(gzdeflate,             			NULL)
	PHP_FE(gzinflate,              			NULL)
	PHP_FE(gzencode,						NULL)
	PHP_FE(ob_gzhandler,					NULL)
	PHP_FE(zlib_get_coding_type,			NULL)
	{NULL, NULL, NULL}
};
/* }}} */

/* {{{ php_zlib_module_entry
 */
zend_module_entry php_zlib_module_entry = {
	STANDARD_MODULE_HEADER,
	"zlib",
	php_zlib_functions,
	PHP_MINIT(zlib),
	PHP_MSHUTDOWN(zlib),
	PHP_RINIT(zlib),
	NULL,
	PHP_MINFO(zlib),
    "1.1",
	STANDARD_MODULE_PROPERTIES
};
/* }}} */

ZEND_DECLARE_MODULE_GLOBALS(zlib)

#ifdef COMPILE_DL_ZLIB
ZEND_GET_MODULE(php_zlib)
#endif

/* {{{ OnUpdate_zlib_output_compression */
static PHP_INI_MH(OnUpdate_zlib_output_compression)
{
	char *ini_value;

	if(new_value == NULL)
		return FAILURE;

	if(!strncasecmp(new_value, "off", sizeof("off"))) {
		new_value = "0";
		new_value_length = sizeof("0");
	} else if(!strncasecmp(new_value, "on", sizeof("on"))) {
		new_value = "1";
		new_value_length = sizeof("1");
	}

	ini_value = zend_ini_string("output_handler", sizeof("output_handler"), 0); 
	if (ini_value != NULL && strlen(ini_value) != 0 && 
		zend_atoi(new_value, new_value_length) != 0) {
		php_error_docref("ref.outcontrol" TSRMLS_CC, E_CORE_ERROR, "Cannot use both zlib.output_compression and output_handler together!!");
		return FAILURE;
	}

	if (stage == PHP_INI_STAGE_RUNTIME && SG(headers_sent) && !SG(request_info).no_headers) {
		php_error_docref("ref.outcontrol" TSRMLS_CC, E_WARNING, "Cannot change zlib.output_compression - headers already sent");
		return FAILURE;
	}

	OnUpdateInt(entry, new_value, new_value_length, mh_arg1, mh_arg2, mh_arg3, stage TSRMLS_CC);

	return SUCCESS;
}
/* }}} */

/* {{{ OnUpdate_zlib_output_compression_level */
static PHP_INI_MH(OnUpdate_zlib_output_compression_level)
{
	OnUpdateInt(entry, new_value, new_value_length, mh_arg1, mh_arg2, mh_arg3, stage TSRMLS_CC);

	return SUCCESS;
}
/* }}} */

/* {{{ OnUpdate_zlib_output_handler */
static PHP_INI_MH(OnUpdate_zlib_output_handler)
{
	if (stage == PHP_INI_STAGE_RUNTIME && SG(headers_sent) && !SG(request_info).no_headers) {
		php_error_docref("ref.outcontrol" TSRMLS_CC, E_WARNING, "Cannot change zlib.output_handler - headers already sent");
		return FAILURE;
	}

	OnUpdateString(entry, new_value, new_value_length, mh_arg1, mh_arg2, mh_arg3, stage TSRMLS_CC);

	return SUCCESS;
}
/* }}} */


PHP_INI_BEGIN()
    STD_PHP_INI_BOOLEAN("zlib.output_compression",      "0", PHP_INI_ALL, OnUpdate_zlib_output_compression,       output_compression,       zend_zlib_globals, zlib_globals)
	STD_PHP_INI_ENTRY("zlib.output_compression_level", "-1", PHP_INI_ALL, OnUpdate_zlib_output_compression_level, output_compression_level, zend_zlib_globals, zlib_globals)
	STD_PHP_INI_ENTRY("zlib.output_handler",             "", PHP_INI_ALL, OnUpdate_zlib_output_handler,           output_handler,           zend_zlib_globals, zlib_globals)
PHP_INI_END()

#ifdef ZTS
/* {{{ php_zlib_init_globals
 */
static void php_zlib_init_globals(zend_zlib_globals *zlib_globals_p TSRMLS_DC)
{
}
/* }}} */
#endif

/* {{{ PHP_MINIT_FUNCTION
 */
PHP_MINIT_FUNCTION(zlib)
{
#ifdef ZTS
	ts_allocate_id(&zlib_globals_id, sizeof(zend_zlib_globals), (ts_allocate_ctor) php_zlib_init_globals, NULL);
#endif
	php_register_url_stream_wrapper("compress.zlib", &php_stream_gzip_wrapper TSRMLS_CC);

	REGISTER_LONG_CONSTANT("FORCE_GZIP", CODING_GZIP, CONST_CS | CONST_PERSISTENT);
	REGISTER_LONG_CONSTANT("FORCE_DEFLATE", CODING_DEFLATE, CONST_CS | CONST_PERSISTENT);

	REGISTER_INI_ENTRIES();

	return SUCCESS;
}
/* }}} */

/* {{{ PHP_RINIT_FUNCTION
 */
PHP_RINIT_FUNCTION(zlib)
{
	uint chunk_size = ZLIBG(output_compression);

	ZLIBG(ob_gzhandler_status) = 0;
	ZLIBG(ob_gzip_coding) = 0;
	if (chunk_size) {
		if (chunk_size == 1) {
			chunk_size = 4096; /* use the default size */
			ZLIBG(output_compression) = chunk_size;
		}
		php_enable_output_compression(chunk_size TSRMLS_CC);
	}
	return SUCCESS;
}
/* }}} */

/* {{{ PHP_MSHUTDOWN_FUNCTION
 */
PHP_MSHUTDOWN_FUNCTION(zlib)
{
	php_unregister_url_stream_wrapper("zlib" TSRMLS_CC);
	
	UNREGISTER_INI_ENTRIES();

	return SUCCESS;
}
/* }}} */

/* {{{ PHP_MINFO_FUNCTION
 */
PHP_MINFO_FUNCTION(zlib)
{
	php_info_print_table_start();
	php_info_print_table_row(2, "ZLib Support", "enabled");
	php_info_print_table_row(2, "Compiled Version", ZLIB_VERSION );
	php_info_print_table_row(2, "Linked Version", (char *)zlibVersion() );
	php_info_print_table_end();

	DISPLAY_INI_ENTRIES();
}
/* }}} */

/* {{{ proto array gzfile(string filename [, int use_include_path])
   Read und uncompress entire .gz-file into an array */
PHP_FUNCTION(gzfile)
{
	pval **filename, **arg2;
	char *slashed, buf[8192];
	register int i=0;
	int use_include_path = 0;
	php_stream *stream;

	/* check args */
	switch (ZEND_NUM_ARGS()) {
	case 1:
		if (zend_get_parameters_ex(1,&filename) == FAILURE) {
			WRONG_PARAM_COUNT;
		}
		break;
	case 2:
		if (zend_get_parameters_ex(2,&filename,&arg2) == FAILURE) {
			WRONG_PARAM_COUNT;
		}
		convert_to_long_ex(arg2);
		use_include_path = Z_LVAL_PP(arg2)?USE_PATH:0;
		break;
	default:
		WRONG_PARAM_COUNT;
	}
	convert_to_string_ex(filename);

	/* using a stream here is a bit more efficient (resource wise) than php_gzopen_wrapper */
	stream = php_stream_gzopen(NULL, Z_STRVAL_PP(filename), "rb", use_include_path|ENFORCE_SAFE_MODE|REPORT_ERRORS, NULL, NULL STREAMS_CC TSRMLS_CC);
	if (stream == NULL) {
		/* Error reporting is already done by stream code */
		RETURN_FALSE;
	}

	/* Initialize return array */
	if (array_init(return_value) == FAILURE) {
		RETURN_FALSE;
	}

	/* Now loop through the file and do the magic quotes thing if needed */
	memset(buf,0,sizeof(buf));
	while(php_stream_gets(stream, buf, sizeof(buf)-1) != NULL) {
		if (PG(magic_quotes_runtime)) {
			int len;
			
			slashed = php_addslashes(buf,0,&len,0 TSRMLS_CC); /* 0 = don't free source string */
            add_index_stringl(return_value, i++, slashed, len, 0);
		} else {
			add_index_string(return_value, i++, buf, 1);
		}
	}
	php_stream_close(stream);
}
/* }}} */

/* {{{ proto int gzopen(string filename, string mode [, int use_include_path])
   Open a .gz-file and return a .gz-file pointer */
PHP_FUNCTION(gzopen)
{
	pval **arg1, **arg2, **arg3;
	php_stream *stream;
	int use_include_path = 0;
	
	switch(ZEND_NUM_ARGS()) {
	case 2:
		if (zend_get_parameters_ex(2,&arg1,&arg2) == FAILURE) {
			WRONG_PARAM_COUNT;
		}
		break;
	case 3:
		if (zend_get_parameters_ex(3,&arg1,&arg2,&arg3) == FAILURE) {
			WRONG_PARAM_COUNT;
		}
		convert_to_long_ex(arg3);
		use_include_path = Z_LVAL_PP(arg3)?USE_PATH:0;
		break;
	default:
		WRONG_PARAM_COUNT;
	}
	convert_to_string_ex(arg1);
	convert_to_string_ex(arg2);
	
	stream = php_stream_gzopen(NULL, Z_STRVAL_PP(arg1), Z_STRVAL_PP(arg2), use_include_path|ENFORCE_SAFE_MODE|REPORT_ERRORS, NULL, NULL STREAMS_CC TSRMLS_CC);

	if (!stream) {
		RETURN_FALSE;
	}
	php_stream_to_zval(stream, return_value);
}	
/* }}} */

/*
 * Read a file and write the ouput to stdout
 */
/* {{{ proto int readgzfile(string filename [, int use_include_path])
   Output a .gz-file */
PHP_FUNCTION(readgzfile)
{
	pval **arg1, **arg2;
	php_stream * stream;
	int size;
	int use_include_path = 0;

	
	/* check args */
	switch (ZEND_NUM_ARGS()) {
	case 1:
		if (zend_get_parameters_ex(1,&arg1) == FAILURE) {
			WRONG_PARAM_COUNT;
		}
		break;
	case 2:
		if (zend_get_parameters_ex(2,&arg1,&arg2) == FAILURE) {
			WRONG_PARAM_COUNT;
		}
		convert_to_long_ex(arg2);
		use_include_path = Z_LVAL_PP(arg2)?USE_PATH:0;
		break;
	default:
		WRONG_PARAM_COUNT;
	}
	convert_to_string_ex(arg1);

	stream = php_stream_gzopen(NULL, Z_STRVAL_PP(arg1), "rb", use_include_path|ENFORCE_SAFE_MODE, NULL, NULL STREAMS_CC TSRMLS_CC);
	if (!stream) {
		RETURN_FALSE;
	}
	size = php_stream_passthru(stream);
   	php_stream_close(stream);
	RETURN_LONG(size);
}
/* }}} */

/* {{{ proto string gzcompress(string data [, int level]) 
   Gzip-compress a string */
PHP_FUNCTION(gzcompress)
{
	zval **data, **zlimit = NULL;
	int limit,status;
	unsigned long l2;
	char *s2;

	switch (ZEND_NUM_ARGS()) {
	case 1:
		if (zend_get_parameters_ex(1, &data) == FAILURE)
			WRONG_PARAM_COUNT;
		limit=-1;
		break;
	case 2:
		if (zend_get_parameters_ex(2, &data, &zlimit) == FAILURE)
			WRONG_PARAM_COUNT;
		convert_to_long_ex(zlimit);
		limit = Z_LVAL_PP(zlimit);
		if((limit<0)||(limit>9)) {
			php_error_docref(NULL TSRMLS_CC, E_WARNING, "compression level(%d) must be within 0..9", limit);
			RETURN_FALSE;
		}
		break;
	default:
		WRONG_PARAM_COUNT;                                         
	}
	convert_to_string_ex(data);
	
	l2 = Z_STRLEN_PP(data) + (Z_STRLEN_PP(data)/1000) + 15 + 1; /* room for \0 */
	s2 = (char *) emalloc(l2);
	if(! s2) RETURN_FALSE;
	
	if(limit>=0) {
		status = compress2(s2,&l2,Z_STRVAL_PP(data), Z_STRLEN_PP(data),limit);
	} else {
		status = compress(s2,&l2,Z_STRVAL_PP(data), Z_STRLEN_PP(data));
	}
	
	if (status==Z_OK) {
		s2 = erealloc(s2,l2 + 1);
		s2[l2] = '\0';
		RETURN_STRINGL(s2, l2, 0);
	} else {
		efree(s2);
		php_error_docref(NULL TSRMLS_CC, E_WARNING, "%s", zError(status));
		RETURN_FALSE;
	}
}
/* }}} */

/* {{{ proto string gzuncompress(string data [, int length]) 
   Unzip a gzip-compressed string */
PHP_FUNCTION(gzuncompress)
{
	zval **data, **zlimit = NULL;
	int status,factor=1,maxfactor=16;
	unsigned long plength=0,length;
	char *s1=NULL,*s2=NULL;

	switch (ZEND_NUM_ARGS()) {
	case 1:
		if (zend_get_parameters_ex(1, &data) == FAILURE)
			WRONG_PARAM_COUNT;
		length=0;
		break;
	case 2:
		if (zend_get_parameters_ex(2, &data, &zlimit) == FAILURE)
			WRONG_PARAM_COUNT;
		convert_to_long_ex(zlimit);
		if(Z_LVAL_PP(zlimit)<=0) {
			php_error_docref(NULL TSRMLS_CC, E_WARNING, "length must be greater zero");
			RETURN_FALSE;
		}
		plength = Z_LVAL_PP(zlimit);
		break;
	default:
		WRONG_PARAM_COUNT;                                         
	}
	convert_to_string_ex(data);

	/*
	 zlib::uncompress() wants to know the output data length
	 if none was given as a parameter
	 we try from input length * 2 up to input length * 2^8
	 doubling it whenever it wasn't big enough
	 that should be eneugh for all real life cases	
	*/
	do {
		length=plength?plength:Z_STRLEN_PP(data)*(1<<factor++);
		s2 = (char *) erealloc(s1,length);
		if(! s2) { if(s1) efree(s1); RETURN_FALSE; }
		status = uncompress(s2, &length ,Z_STRVAL_PP(data), Z_STRLEN_PP(data));
		s1=s2;
	} while((status==Z_BUF_ERROR)&&(!plength)&&(factor<maxfactor));

	if (status==Z_OK) {
		s2 = erealloc(s2, length + 1); /* space for \0 */
		s2[ length ] = '\0';
		RETURN_STRINGL(s2, length, 0);
	} else {
		efree(s2);
		php_error_docref(NULL TSRMLS_CC, E_WARNING, "%s", zError(status));
		RETURN_FALSE;
	}
}
/* }}} */

/* {{{ proto string gzdeflate(string data [, int level]) 
   Gzip-compress a string */
PHP_FUNCTION(gzdeflate)
{
	zval **data, **zlimit = NULL;
	int level,status;
	z_stream stream;
	char *s2;

	switch (ZEND_NUM_ARGS()) {
	case 1:
		if (zend_get_parameters_ex(1, &data) == FAILURE)
			WRONG_PARAM_COUNT;
		level=Z_DEFAULT_COMPRESSION;
		break;
	case 2:
		if (zend_get_parameters_ex(2, &data, &zlimit) == FAILURE)
			WRONG_PARAM_COUNT;
		convert_to_long_ex(zlimit);
		level = Z_LVAL_PP(zlimit);
		if((level<0)||(level>9)) {
			php_error_docref(NULL TSRMLS_CC, E_WARNING, "compression level(%d) must be within 0..9", level);
			RETURN_FALSE;
		}
		break;
	default:
		WRONG_PARAM_COUNT;                                         
	}
	convert_to_string_ex(data);

	stream.data_type = Z_ASCII;
	stream.zalloc = (alloc_func) Z_NULL;
	stream.zfree  = (free_func) Z_NULL;
	stream.opaque = (voidpf) Z_NULL;

	stream.next_in = (Bytef*) Z_STRVAL_PP(data);
	stream.avail_in = Z_STRLEN_PP(data);

	stream.avail_out = stream.avail_in + (stream.avail_in/1000) + 15 + 1; /* room for \0 */
	s2 = (char *) emalloc(stream.avail_out);
	if(!s2) RETURN_FALSE;
	stream.next_out = s2;

    /* init with -MAX_WBITS disables the zlib internal headers */
	status = deflateInit2(&stream, level, Z_DEFLATED, -MAX_WBITS, MAX_MEM_LEVEL, 0);
	if (status == Z_OK) {

		status = deflate(&stream, Z_FINISH);
		if (status != Z_STREAM_END) {
			deflateEnd(&stream);
			if (status == Z_OK) {
				status = Z_BUF_ERROR;
			}
		} else {
			status = deflateEnd(&stream);
		}
	}

	if (status==Z_OK) {
		s2 = erealloc(s2,stream.total_out+1); /* resize to buffer to the "right" size */
		s2[ stream.total_out ] = '\0';
		RETURN_STRINGL(s2, stream.total_out, 0);
	} else {
		efree(s2);
		php_error_docref(NULL TSRMLS_CC, E_WARNING, "%s", zError(status));
		RETURN_FALSE;
	}
}
/* }}} */

/* {{{ proto string gzinflate(string data [, int length]) 
   Unzip a gzip-compressed string */
PHP_FUNCTION(gzinflate)
{
	zval **data, **zlimit = NULL;
	int status,factor=1,maxfactor=16;
	unsigned long plength=0,length;
	char *s1=NULL,*s2=NULL;
	z_stream stream;

	switch (ZEND_NUM_ARGS()) {
	case 1:
		if (zend_get_parameters_ex(1, &data) == FAILURE)
			WRONG_PARAM_COUNT;
		length=0;
		break;
	case 2:
		if (zend_get_parameters_ex(2, &data, &zlimit) == FAILURE)
			WRONG_PARAM_COUNT;
		convert_to_long_ex(zlimit);
		if(Z_LVAL_PP(zlimit)<=0) {
			php_error_docref(NULL TSRMLS_CC, E_WARNING, "length must be greater zero");
			RETURN_FALSE;
		}
		plength = Z_LVAL_PP(zlimit);
		break;
	default:
		WRONG_PARAM_COUNT;                                         
	}
	convert_to_string_ex(data);

	/*
	  stream.avail_out wants to know the output data length
	  if none was given as a parameter
	  we try from input length * 2 up to input length * 2^16
	  doubling it whenever it wasn't big enough
	  that should be enaugh for all real life cases	
	*/

	stream.zalloc = (alloc_func) Z_NULL;
	stream.zfree = (free_func) Z_NULL;

	do {
		length=plength?plength:Z_STRLEN_PP(data)*(1<<factor++);
		s2 = (char *) erealloc(s1,length);
		if(! s2) { if(s1) efree(s1); RETURN_FALSE; }

		stream.next_in = (Bytef*) Z_STRVAL_PP(data);
		stream.avail_in = (uInt) Z_STRLEN_PP(data) + 1; /* there is room for \0 */

		stream.next_out = s2;
		stream.avail_out = (uInt) length;

		/* init with -MAX_WBITS disables the zlib internal headers */
		status = inflateInit2(&stream, -MAX_WBITS);
		if (status == Z_OK) {
			status = inflate(&stream, Z_FINISH);
			if (status != Z_STREAM_END) {
				inflateEnd(&stream);
				if (status == Z_OK) {
					status = Z_BUF_ERROR;
				}
			} else {
				status = inflateEnd(&stream);
			}
		}
		s1=s2;
		
	} while((status==Z_BUF_ERROR)&&(!plength)&&(factor<maxfactor));

	if(status==Z_OK) {
		s2 = erealloc(s2, stream.total_out + 1); /* room for \0 */
		s2[ stream.total_out ] = '\0';
		RETURN_STRINGL(s2, stream.total_out, 0);
	} else {
		efree(s2);
		php_error_docref(NULL TSRMLS_CC, E_WARNING, "%s", zError(status));
		RETURN_FALSE;
	}
}
/* }}} */

/*`{{{ proto zlib_get_coding_type()
   Returns the coding type used for output compression */

PHP_FUNCTION(zlib_get_coding_type)
{
	switch (ZLIBG(ob_gzip_coding)) {
		case CODING_GZIP:
			RETURN_STRINGL("gzip", sizeof("gzip") - 1, 1);

		case CODING_DEFLATE:
			RETURN_STRINGL("deflate", sizeof("deflate") - 1, 1);
	}

	RETURN_FALSE;
}


/* {{{ php_do_deflate
 */
static int php_do_deflate(uint str_length, Bytef **p_buffer, uint *p_buffer_len, zend_bool do_start, zend_bool do_end TSRMLS_DC)
{
	Bytef *buffer;
	uInt prev_outlen, outlen;
	int err;
	int start_offset = ((do_start && ZLIBG(compression_coding) == CODING_GZIP) ? 10 : 0);
	int end_offset = (do_end?8:0);

	outlen = (uint)(sizeof(char) * (str_length * 1.001f + 12) + 1); /* leave some room for a trailing \0 */
	if ((outlen+start_offset+end_offset) > *p_buffer_len) {
		buffer = (Bytef *) emalloc(outlen+start_offset+end_offset);
	} else {
		buffer = *p_buffer;
	}
	
	ZLIBG(stream).next_out = buffer+start_offset;
	ZLIBG(stream).avail_out = outlen;


	err = deflate(&ZLIBG(stream), Z_SYNC_FLUSH);
	while (err == Z_OK && !ZLIBG(stream).avail_out) {
		prev_outlen = outlen;
		outlen *= 3;
		if ((outlen+start_offset+end_offset) > *p_buffer_len) {
			buffer = erealloc(buffer, outlen+start_offset+end_offset);
		}
		
		ZLIBG(stream).next_out = buffer+start_offset + prev_outlen;
		ZLIBG(stream).avail_out = prev_outlen * 2;

		err = deflate(&ZLIBG(stream), Z_SYNC_FLUSH);
	}

	if (do_end) {
		err = deflate(&ZLIBG(stream), Z_FINISH);
		buffer[outlen + start_offset - ZLIBG(stream).avail_out] = '\0';
	}


	*p_buffer = buffer;
	*p_buffer_len = outlen - ZLIBG(stream).avail_out;

	return err;
}
/* }}} */

/* {{{ php_deflate_string
 */
int php_deflate_string(const char *str, uint str_length, char **newstr, uint *new_length, int coding, zend_bool do_start, zend_bool do_end, int compression_level TSRMLS_DC)
{
	int err;

	ZLIBG(compression_coding) = coding;

	if (do_start) {
		ZLIBG(stream).zalloc = Z_NULL;
		ZLIBG(stream).zfree = Z_NULL;
		ZLIBG(stream).opaque = Z_NULL;
		switch (coding) {
			case CODING_GZIP:
				/* windowBits is passed < 0 to suppress zlib header & trailer */
				if (deflateInit2(&ZLIBG(stream), compression_level, Z_DEFLATED,
						-MAX_WBITS, MAX_MEM_LEVEL, Z_DEFAULT_STRATEGY)
							!= Z_OK) {
					/* TODO: print out error */
					return FAILURE;
				}
		
				ZLIBG(crc) = crc32(0L, Z_NULL, 0);
				break;
			case CODING_DEFLATE:
				if (deflateInit(&ZLIBG(stream), compression_level) != Z_OK) {
					/* TODO: print out error */
					return FAILURE;
				}
				break;		
		}
	}


	ZLIBG(stream).next_in = (Bytef*) str;
	ZLIBG(stream).avail_in = (uInt) str_length;

	if (ZLIBG(compression_coding) == CODING_GZIP) {
		ZLIBG(crc) = crc32(ZLIBG(crc), (const Bytef *) str, str_length);
	}

	err = php_do_deflate(str_length, (Bytef **) newstr, new_length, do_start, do_end TSRMLS_CC);
	/* TODO: error handling (err may be Z_STREAM_ERROR, Z_BUF_ERROR, ?) */

	if (do_start && ZLIBG(compression_coding) == CODING_GZIP) {
		/* Write a very simple .gz header: */
		(*newstr)[0] = gz_magic[0];
		(*newstr)[1] = gz_magic[1];
		(*newstr)[2] = Z_DEFLATED;
		(*newstr)[3] = (*newstr)[4] = (*newstr)[5] = (*newstr)[6] = (*newstr)[7] = (*newstr)[8] = 0;
		(*newstr)[9] = OS_CODE;
		*new_length += 10;
	}
	if (do_end) {
		if (ZLIBG(compression_coding) == CODING_GZIP) {
			char *trailer = (*newstr)+(*new_length);

			/* write crc & stream.total_in in LSB order */
			trailer[0] = (char) ZLIBG(crc) & 0xFF;
			trailer[1] = (char) (ZLIBG(crc) >> 8) & 0xFF;
			trailer[2] = (char) (ZLIBG(crc) >> 16) & 0xFF;
			trailer[3] = (char) (ZLIBG(crc) >> 24) & 0xFF;
			trailer[4] = (char) ZLIBG(stream).total_in & 0xFF;
			trailer[5] = (char) (ZLIBG(stream).total_in >> 8) & 0xFF;
			trailer[6] = (char) (ZLIBG(stream).total_in >> 16) & 0xFF;
			trailer[7] = (char) (ZLIBG(stream).total_in >> 24) & 0xFF;
			trailer[8] = '\0';
			*new_length += 8;
		}
		deflateEnd(&ZLIBG(stream));
	}

	return SUCCESS;
}
/* }}} */

/* {{{ proto string gzencode(string data [, int level [, int encoding_mode]])
   GZ encode a string */
PHP_FUNCTION(gzencode)
{
	char *data, *s2;
	int data_len;
	long level = Z_DEFAULT_COMPRESSION, coding = CODING_GZIP;
	int status;
	z_stream stream;

	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s|ll", &data, &data_len, &level, &coding) == FAILURE) {
		return;
	}

	if((level<-1)||(level>9)) {
		php_error_docref(NULL TSRMLS_CC, E_WARNING, "compression level(%ld) must be within -1..9", level);
		RETURN_FALSE;
	}

	if((coding!=CODING_GZIP)&&(coding!=CODING_DEFLATE)) {
		php_error_docref(NULL TSRMLS_CC, E_WARNING, "encoding mode must be FORCE_GZIP or FORCE_DEFLATE");
		RETURN_FALSE;
	}

	stream.zalloc = Z_NULL;
	stream.zfree = Z_NULL;
	stream.opaque = Z_NULL;

	stream.next_in = (Bytef*) data;
	stream.avail_in = data_len;

	stream.avail_out = stream.avail_in + (stream.avail_in/1000) + 15 + 1; /* room for \0 */
	s2 = (char *) emalloc(stream.avail_out+GZIP_HEADER_LENGTH+(coding==CODING_GZIP?GZIP_FOOTER_LENGTH:0));
	if(!s2)
		RETURN_FALSE;

	/* add gzip file header */
	s2[0] = gz_magic[0];
	s2[1] = gz_magic[1];
	s2[2] = Z_DEFLATED;
	s2[3] = s2[4] = s2[5] = s2[6] = s2[7] = s2[8] = 0; /* time set to 0 */
	s2[9] = OS_CODE;

	stream.next_out = &(s2[GZIP_HEADER_LENGTH]);

	switch (coding) {
		case CODING_GZIP:
			/* windowBits is passed < 0 to suppress zlib header & trailer */
			if ((status = deflateInit2(&stream, level, Z_DEFLATED,
									  -MAX_WBITS, MAX_MEM_LEVEL,
									   Z_DEFAULT_STRATEGY))
							!= Z_OK) {
				php_error_docref(NULL TSRMLS_CC, E_WARNING, "%s", zError(status));
				RETURN_FALSE;
			}
		
			break;
		case CODING_DEFLATE:
			if ((status = deflateInit(&stream, level)) != Z_OK) {
				php_error_docref(NULL TSRMLS_CC, E_WARNING, "%s", zError(status));
				RETURN_FALSE;
			}
			break;		
	}

	status = deflate(&stream, Z_FINISH);
	if (status != Z_STREAM_END) {
		deflateEnd(&stream);
		if (status == Z_OK) {
			status = Z_BUF_ERROR;
		}
	} else {
		status = deflateEnd(&stream);
	}

	if (status==Z_OK) {
		s2 = erealloc(s2,stream.total_out+GZIP_HEADER_LENGTH+(coding==CODING_GZIP?GZIP_FOOTER_LENGTH:0)+1); /* resize to buffer to the "right" size */
		if (coding == CODING_GZIP) {
			char *trailer = s2+(stream.total_out+GZIP_HEADER_LENGTH);
			uLong crc = crc32(0L, Z_NULL, 0);

			crc = crc32(crc, (const Bytef *) data, data_len);

			/* write crc & stream.total_in in LSB order */
			trailer[0] = (char) crc & 0xFF;
			trailer[1] = (char) (crc >> 8) & 0xFF;
			trailer[2] = (char) (crc >> 16) & 0xFF;
			trailer[3] = (char) (crc >> 24) & 0xFF;
			trailer[4] = (char) stream.total_in & 0xFF;
			trailer[5] = (char) (stream.total_in >> 8) & 0xFF;
			trailer[6] = (char) (stream.total_in >> 16) & 0xFF;
			trailer[7] = (char) (stream.total_in >> 24) & 0xFF;
			trailer[8] = '\0';
	}
		RETURN_STRINGL(s2, stream.total_out+GZIP_HEADER_LENGTH+(coding==CODING_GZIP?GZIP_FOOTER_LENGTH:0), 0);
	} else {
		efree(s2);
		php_error_docref(NULL TSRMLS_CC, E_WARNING, "%s", zError(status));
		RETURN_FALSE;
	}
}
/* }}} */

/* {{{ php_ob_gzhandler_check
 */
int php_ob_gzhandler_check(TSRMLS_D)
{
	/* check for wrong usages */
	if (OG(ob_nesting_level>0)) {
		if (php_ob_handler_used("ob_gzhandler" TSRMLS_CC)) {
			php_error_docref("ref.outcontrol" TSRMLS_CC, E_WARNING, "output handler 'ob_gzhandler' cannot be used twice");
			return FAILURE;
		}
		if (php_ob_handler_used("mb_output_handler" TSRMLS_CC)) {
			php_error_docref("ref.outcontrol" TSRMLS_CC, E_WARNING, "output handler 'ob_gzhandler' cannot be used after 'mb_output_handler'");
			return FAILURE;
		}
		if (php_ob_handler_used("URL-Rewriter" TSRMLS_CC)) {
			php_error_docref("ref.outcontrol" TSRMLS_CC, E_WARNING, "output handler 'ob_gzhandler' cannot be used after 'URL-Rewriter'");
			return FAILURE;
		}
		if (php_ob_init_conflict("ob_gzhandler", "zlib output compression" TSRMLS_CC)) {
			return FAILURE;
		}
	}

	return SUCCESS;
}

/* }}} */

/* {{{ proto string ob_gzhandler(string str, int mode)
   Encode str based on accept-encoding setting - designed to be called from ob_start() */
PHP_FUNCTION(ob_gzhandler)
{
	int coding;
	zval **zv_string, **zv_mode;
	zval **data, **a_encoding;
	zend_bool return_original=0;
	zend_bool do_start, do_end;

	if (ZEND_NUM_ARGS()!=2 || zend_get_parameters_ex(2, &zv_string, &zv_mode)==FAILURE) {
		ZEND_WRONG_PARAM_COUNT();
	}

	if (ZLIBG(ob_gzhandler_status)==-1
		|| zend_hash_find(&EG(symbol_table), "HTTP_SERVER_VARS", sizeof("HTTP_SERVER_VARS"), (void **) &data)==FAILURE
		|| Z_TYPE_PP(data)!=IS_ARRAY
		|| zend_hash_find(Z_ARRVAL_PP(data), "HTTP_ACCEPT_ENCODING", sizeof("HTTP_ACCEPT_ENCODING"), (void **) &a_encoding)==FAILURE) {
		ZLIBG(ob_gzhandler_status)=-1;
		RETURN_FALSE;
	}
	convert_to_string_ex(a_encoding);
	if (php_memnstr(Z_STRVAL_PP(a_encoding), "gzip", 4, Z_STRVAL_PP(a_encoding) + Z_STRLEN_PP(a_encoding))) {
		coding = CODING_GZIP;
	} else if(php_memnstr(Z_STRVAL_PP(a_encoding), "deflate", 7, Z_STRVAL_PP(a_encoding) + Z_STRLEN_PP(a_encoding))) {
		coding = CODING_DEFLATE;
	} else {
		ZLIBG(ob_gzhandler_status)=-1;
		RETURN_FALSE;
	}
	
	convert_to_long_ex(zv_mode);
	do_start = ((Z_LVAL_PP(zv_mode) & PHP_OUTPUT_HANDLER_START) ? 1 : 0);
	do_end = ((Z_LVAL_PP(zv_mode) & PHP_OUTPUT_HANDLER_END) ? 1 : 0);
	Z_STRVAL_P(return_value) = NULL;
	Z_STRLEN_P(return_value) = 0;
	if (php_deflate_string(Z_STRVAL_PP(zv_string), Z_STRLEN_PP(zv_string), &Z_STRVAL_P(return_value), &Z_STRLEN_P(return_value), coding, do_start, do_end, ZLIBG(output_compression_level) TSRMLS_CC)==SUCCESS) {
		Z_TYPE_P(return_value) = IS_STRING;
		if (do_start) {
			switch (coding) {
				case CODING_GZIP:
					if (sapi_add_header("Content-Encoding: gzip", sizeof("Content-Encoding: gzip") - 1, 1)==FAILURE) {
						return_original = 1;
					}
					if (sapi_add_header_ex("Vary: Accept-Encoding", sizeof("Vary: Accept-Encoding") - 1, 1, 0 TSRMLS_CC)==FAILURE) {
						return_original = 1;
					}
					break;
				case CODING_DEFLATE:
					if (sapi_add_header("Content-Encoding: deflate", sizeof("Content-Encoding: deflate") - 1, 1)==FAILURE) {
						return_original = 1;
					}
					if (sapi_add_header_ex("Vary: Accept-Encoding", sizeof("Vary: Accept-Encoding") - 1, 1, 0 TSRMLS_CC)==FAILURE) {
						return_original = 1;
					}
					break;
				default:
					return_original = 1;
					break;
			}
		}

		if (return_original) {
			zval_dtor(return_value);
		}

	} else {
		return_original = 1;
	}

	if (return_original) {
		/* return the original string */
		*return_value = **zv_string;
		zval_copy_ctor(return_value);
	}
}
/* }}} */

/* {{{ php_gzip_output_handler
 */
static void php_gzip_output_handler(char *output, uint output_len, char **handled_output, uint *handled_output_len, int mode TSRMLS_DC)
{
	zend_bool do_start, do_end;

	if (!ZLIBG(output_compression)) {
		*handled_output = NULL;
	} else {
		do_start = (mode & PHP_OUTPUT_HANDLER_START ? 1 : 0);
		do_end = (mode & PHP_OUTPUT_HANDLER_END ? 1 : 0);
		if (php_deflate_string(output, output_len, handled_output, handled_output_len, ZLIBG(ob_gzip_coding), do_start, do_end, ZLIBG(output_compression_level) TSRMLS_CC)!=SUCCESS) {
			zend_error(E_ERROR, "Compression failed");
		}
	}
}
/* }}} */

/* {{{ php_enable_output_compression
 */
int php_enable_output_compression(int buffer_size TSRMLS_DC)
{
	zval **a_encoding, **data;

	if (zend_hash_find(&EG(symbol_table), "HTTP_SERVER_VARS", sizeof("HTTP_SERVER_VARS"), (void **) &data)==FAILURE
		|| Z_TYPE_PP(data)!=IS_ARRAY
		|| zend_hash_find(Z_ARRVAL_PP(data), "HTTP_ACCEPT_ENCODING", sizeof("HTTP_ACCEPT_ENCODING"), (void **) &a_encoding)==FAILURE) {
		return FAILURE;
	}
	convert_to_string_ex(a_encoding);
	if (php_memnstr(Z_STRVAL_PP(a_encoding), "gzip", 4, Z_STRVAL_PP(a_encoding) + Z_STRLEN_PP(a_encoding))) {
		ZLIBG(ob_gzip_coding) = CODING_GZIP;
	} else if(php_memnstr(Z_STRVAL_PP(a_encoding), "deflate", 7, Z_STRVAL_PP(a_encoding) + Z_STRLEN_PP(a_encoding))) {
		ZLIBG(ob_gzip_coding) = CODING_DEFLATE;
	} else {
		return FAILURE;
	}

	php_ob_set_internal_handler(php_gzip_output_handler, (uint)buffer_size, "zlib output compression", 0 TSRMLS_CC);
	if (ZLIBG(output_handler) && strlen(ZLIBG(output_handler))) {
		php_start_ob_buffer_named(ZLIBG(output_handler), 0, 1 TSRMLS_CC);
	}
	return SUCCESS;
}
/* }}} */

/*
 * Local variables:
 * tab-width: 4
 * c-basic-offset: 4
 * End:
 * vim600: sw=4 ts=4 fdm=marker
 * vim<600: sw=4 ts=4
 */