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reactos/dll/win32/itss/chm_lib.c
Hermès Bélusca-Maïto 49ab546ac3 Sync up with trunk r61578. 
svn path=/branches/ntvdm/; revision=61579
2014-01-11 00:00:10 +00:00

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/***************************************************************************
* chm_lib.c - CHM archive manipulation routines *
* ------------------- *
* *
* author: Jed Wing <jedwin@ugcs.caltech.edu> *
* version: 0.3 *
* notes: These routines are meant for the manipulation of microsoft *
* .chm (compiled html help) files, but may likely be used *
* for the manipulation of any ITSS archive, if ever ITSS *
* archives are used for any other purpose. *
* *
* Note also that the section names are statically handled. *
* To be entirely correct, the section names should be read *
* from the section names meta-file, and then the various *
* content sections and the "transforms" to apply to the data *
* they contain should be inferred from the section name and *
* the meta-files referenced using that name; however, all of *
* the files I've been able to get my hands on appear to have *
* only two sections: Uncompressed and MSCompressed. *
* Additionally, the ITSS.DLL file included with Windows does *
* not appear to handle any different transforms than the *
* simple LZX-transform. Furthermore, the list of transforms *
* to apply is broken, in that only half the required space *
* is allocated for the list. (It appears as though the *
* space is allocated for ASCII strings, but the strings are *
* written as unicode. As a result, only the first half of *
* the string appears.) So this is probably not too big of *
* a deal, at least until CHM v4 (MS .lit files), which also *
* incorporate encryption, of some description. *
* *
***************************************************************************/
/***************************************************************************
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
*
***************************************************************************/
/***************************************************************************
* *
* Adapted for Wine by Mike McCormack *
* *
***************************************************************************/
#include "precomp.h"
#define CHM_ACQUIRE_LOCK(a) do { \
EnterCriticalSection(&(a)); \
} while(0)
#define CHM_RELEASE_LOCK(a) do { \
LeaveCriticalSection(&(a)); \
} while(0)
#define CHM_NULL_FD (INVALID_HANDLE_VALUE)
#define CHM_CLOSE_FILE(fd) CloseHandle((fd))
/*
* defines related to tuning
*/
#ifndef CHM_MAX_BLOCKS_CACHED
#define CHM_MAX_BLOCKS_CACHED 5
#endif
#define CHM_PARAM_MAX_BLOCKS_CACHED 0
/*
* architecture specific defines
*
* Note: as soon as C99 is more widespread, the below defines should
* probably just use the C99 sized-int types.
*
* The following settings will probably work for many platforms. The sizes
* don't have to be exactly correct, but the types must accommodate at least as
* many bits as they specify.
*/
/* i386, 32-bit, Windows */
typedef BYTE UChar;
typedef SHORT Int16;
typedef USHORT UInt16;
typedef LONG Int32;
typedef DWORD UInt32;
typedef LONGLONG Int64;
typedef ULONGLONG UInt64;
/* utilities for unmarshalling data */
static int _unmarshal_char_array(unsigned char **pData,
unsigned int *pLenRemain,
char *dest,
int count)
{
if (count <= 0 || (unsigned int)count > *pLenRemain)
return 0;
memcpy(dest, (*pData), count);
*pData += count;
*pLenRemain -= count;
return 1;
}
static int _unmarshal_uchar_array(unsigned char **pData,
unsigned int *pLenRemain,
unsigned char *dest,
int count)
{
if (count <= 0 || (unsigned int)count > *pLenRemain)
return 0;
memcpy(dest, (*pData), count);
*pData += count;
*pLenRemain -= count;
return 1;
}
static int _unmarshal_int32(unsigned char **pData,
unsigned int *pLenRemain,
Int32 *dest)
{
if (4 > *pLenRemain)
return 0;
*dest = (*pData)[0] | (*pData)[1]<<8 | (*pData)[2]<<16 | (*pData)[3]<<24;
*pData += 4;
*pLenRemain -= 4;
return 1;
}
static int _unmarshal_uint32(unsigned char **pData,
unsigned int *pLenRemain,
UInt32 *dest)
{
if (4 > *pLenRemain)
return 0;
*dest = (*pData)[0] | (*pData)[1]<<8 | (*pData)[2]<<16 | (*pData)[3]<<24;
*pData += 4;
*pLenRemain -= 4;
return 1;
}
static int _unmarshal_int64(unsigned char **pData,
unsigned int *pLenRemain,
Int64 *dest)
{
Int64 temp;
int i;
if (8 > *pLenRemain)
return 0;
temp=0;
for(i=8; i>0; i--)
{
temp <<= 8;
temp |= (*pData)[i-1];
}
*dest = temp;
*pData += 8;
*pLenRemain -= 8;
return 1;
}
static int _unmarshal_uint64(unsigned char **pData,
unsigned int *pLenRemain,
UInt64 *dest)
{
UInt64 temp;
int i;
if (8 > *pLenRemain)
return 0;
temp=0;
for(i=8; i>0; i--)
{
temp <<= 8;
temp |= (*pData)[i-1];
}
*dest = temp;
*pData += 8;
*pLenRemain -= 8;
return 1;
}
static int _unmarshal_uuid(unsigned char **pData,
unsigned int *pDataLen,
unsigned char *dest)
{
return _unmarshal_uchar_array(pData, pDataLen, dest, 16);
}
/* names of sections essential to decompression */
static const WCHAR _CHMU_RESET_TABLE[] = {
':',':','D','a','t','a','S','p','a','c','e','/',
'S','t','o','r','a','g','e','/',
'M','S','C','o','m','p','r','e','s','s','e','d','/',
'T','r','a','n','s','f','o','r','m','/',
'{','7','F','C','2','8','9','4','0','-','9','D','3','1',
'-','1','1','D','0','-','9','B','2','7','-',
'0','0','A','0','C','9','1','E','9','C','7','C','}','/',
'I','n','s','t','a','n','c','e','D','a','t','a','/',
'R','e','s','e','t','T','a','b','l','e',0
};
static const WCHAR _CHMU_LZXC_CONTROLDATA[] = {
':',':','D','a','t','a','S','p','a','c','e','/',
'S','t','o','r','a','g','e','/',
'M','S','C','o','m','p','r','e','s','s','e','d','/',
'C','o','n','t','r','o','l','D','a','t','a',0
};
static const WCHAR _CHMU_CONTENT[] = {
':',':','D','a','t','a','S','p','a','c','e','/',
'S','t','o','r','a','g','e','/',
'M','S','C','o','m','p','r','e','s','s','e','d','/',
'C','o','n','t','e','n','t',0
};
/*
* structures local to this module
*/
/* structure of ITSF headers */
#define _CHM_ITSF_V2_LEN (0x58)
#define _CHM_ITSF_V3_LEN (0x60)
struct chmItsfHeader
{
char signature[4]; /* 0 (ITSF) */
Int32 version; /* 4 */
Int32 header_len; /* 8 */
Int32 unknown_000c; /* c */
UInt32 last_modified; /* 10 */
UInt32 lang_id; /* 14 */
UChar dir_uuid[16]; /* 18 */
UChar stream_uuid[16]; /* 28 */
UInt64 unknown_offset; /* 38 */
UInt64 unknown_len; /* 40 */
UInt64 dir_offset; /* 48 */
UInt64 dir_len; /* 50 */
UInt64 data_offset; /* 58 (Not present before V3) */
}; /* __attribute__ ((aligned (1))); */
static int _unmarshal_itsf_header(unsigned char **pData,
unsigned int *pDataLen,
struct chmItsfHeader *dest)
{
/* we only know how to deal with the 0x58 and 0x60 byte structures */
if (*pDataLen != _CHM_ITSF_V2_LEN && *pDataLen != _CHM_ITSF_V3_LEN)
return 0;
/* unmarshal common fields */
_unmarshal_char_array(pData, pDataLen, dest->signature, 4);
_unmarshal_int32 (pData, pDataLen, &dest->version);
_unmarshal_int32 (pData, pDataLen, &dest->header_len);
_unmarshal_int32 (pData, pDataLen, &dest->unknown_000c);
_unmarshal_uint32 (pData, pDataLen, &dest->last_modified);
_unmarshal_uint32 (pData, pDataLen, &dest->lang_id);
_unmarshal_uuid (pData, pDataLen, dest->dir_uuid);
_unmarshal_uuid (pData, pDataLen, dest->stream_uuid);
_unmarshal_uint64 (pData, pDataLen, &dest->unknown_offset);
_unmarshal_uint64 (pData, pDataLen, &dest->unknown_len);
_unmarshal_uint64 (pData, pDataLen, &dest->dir_offset);
_unmarshal_uint64 (pData, pDataLen, &dest->dir_len);
/* error check the data */
/* XXX: should also check UUIDs, probably, though with a version 3 file,
* current MS tools do not seem to use them.
*/
if (memcmp(dest->signature, "ITSF", 4) != 0)
return 0;
if (dest->version == 2)
{
if (dest->header_len < _CHM_ITSF_V2_LEN)
return 0;
}
else if (dest->version == 3)
{
if (dest->header_len < _CHM_ITSF_V3_LEN)
return 0;
}
else
return 0;
/* now, if we have a V3 structure, unmarshal the rest.
* otherwise, compute it
*/
if (dest->version == 3)
{
if (*pDataLen != 0)
_unmarshal_uint64(pData, pDataLen, &dest->data_offset);
else
return 0;
}
else
dest->data_offset = dest->dir_offset + dest->dir_len;
return 1;
}
/* structure of ITSP headers */
#define _CHM_ITSP_V1_LEN (0x54)
struct chmItspHeader
{
char signature[4]; /* 0 (ITSP) */
Int32 version; /* 4 */
Int32 header_len; /* 8 */
Int32 unknown_000c; /* c */
UInt32 block_len; /* 10 */
Int32 blockidx_intvl; /* 14 */
Int32 index_depth; /* 18 */
Int32 index_root; /* 1c */
Int32 index_head; /* 20 */
Int32 unknown_0024; /* 24 */
UInt32 num_blocks; /* 28 */
Int32 unknown_002c; /* 2c */
UInt32 lang_id; /* 30 */
UChar system_uuid[16]; /* 34 */
UChar unknown_0044[16]; /* 44 */
}; /* __attribute__ ((aligned (1))); */
static int _unmarshal_itsp_header(unsigned char **pData,
unsigned int *pDataLen,
struct chmItspHeader *dest)
{
/* we only know how to deal with a 0x54 byte structures */
if (*pDataLen != _CHM_ITSP_V1_LEN)
return 0;
/* unmarshal fields */
_unmarshal_char_array(pData, pDataLen, dest->signature, 4);
_unmarshal_int32 (pData, pDataLen, &dest->version);
_unmarshal_int32 (pData, pDataLen, &dest->header_len);
_unmarshal_int32 (pData, pDataLen, &dest->unknown_000c);
_unmarshal_uint32 (pData, pDataLen, &dest->block_len);
_unmarshal_int32 (pData, pDataLen, &dest->blockidx_intvl);
_unmarshal_int32 (pData, pDataLen, &dest->index_depth);
_unmarshal_int32 (pData, pDataLen, &dest->index_root);
_unmarshal_int32 (pData, pDataLen, &dest->index_head);
_unmarshal_int32 (pData, pDataLen, &dest->unknown_0024);
_unmarshal_uint32 (pData, pDataLen, &dest->num_blocks);
_unmarshal_int32 (pData, pDataLen, &dest->unknown_002c);
_unmarshal_uint32 (pData, pDataLen, &dest->lang_id);
_unmarshal_uuid (pData, pDataLen, dest->system_uuid);
_unmarshal_uchar_array(pData, pDataLen, dest->unknown_0044, 16);
/* error check the data */
if (memcmp(dest->signature, "ITSP", 4) != 0)
return 0;
if (dest->version != 1)
return 0;
if (dest->header_len != _CHM_ITSP_V1_LEN)
return 0;
return 1;
}
/* structure of PMGL headers */
static const char _chm_pmgl_marker[4] = "PMGL";
#define _CHM_PMGL_LEN (0x14)
struct chmPmglHeader
{
char signature[4]; /* 0 (PMGL) */
UInt32 free_space; /* 4 */
UInt32 unknown_0008; /* 8 */
Int32 block_prev; /* c */
Int32 block_next; /* 10 */
}; /* __attribute__ ((aligned (1))); */
static int _unmarshal_pmgl_header(unsigned char **pData,
unsigned int *pDataLen,
struct chmPmglHeader *dest)
{
/* we only know how to deal with a 0x14 byte structures */
if (*pDataLen != _CHM_PMGL_LEN)
return 0;
/* unmarshal fields */
_unmarshal_char_array(pData, pDataLen, dest->signature, 4);
_unmarshal_uint32 (pData, pDataLen, &dest->free_space);
_unmarshal_uint32 (pData, pDataLen, &dest->unknown_0008);
_unmarshal_int32 (pData, pDataLen, &dest->block_prev);
_unmarshal_int32 (pData, pDataLen, &dest->block_next);
/* check structure */
if (memcmp(dest->signature, _chm_pmgl_marker, 4) != 0)
return 0;
return 1;
}
/* structure of PMGI headers */
static const char _chm_pmgi_marker[4] = "PMGI";
#define _CHM_PMGI_LEN (0x08)
struct chmPmgiHeader
{
char signature[4]; /* 0 (PMGI) */
UInt32 free_space; /* 4 */
}; /* __attribute__ ((aligned (1))); */
static int _unmarshal_pmgi_header(unsigned char **pData,
unsigned int *pDataLen,
struct chmPmgiHeader *dest)
{
/* we only know how to deal with a 0x8 byte structures */
if (*pDataLen != _CHM_PMGI_LEN)
return 0;
/* unmarshal fields */
_unmarshal_char_array(pData, pDataLen, dest->signature, 4);
_unmarshal_uint32 (pData, pDataLen, &dest->free_space);
/* check structure */
if (memcmp(dest->signature, _chm_pmgi_marker, 4) != 0)
return 0;
return 1;
}
/* structure of LZXC reset table */
#define _CHM_LZXC_RESETTABLE_V1_LEN (0x28)
struct chmLzxcResetTable
{
UInt32 version;
UInt32 block_count;
UInt32 unknown;
UInt32 table_offset;
UInt64 uncompressed_len;
UInt64 compressed_len;
UInt64 block_len;
}; /* __attribute__ ((aligned (1))); */
static int _unmarshal_lzxc_reset_table(unsigned char **pData,
unsigned int *pDataLen,
struct chmLzxcResetTable *dest)
{
/* we only know how to deal with a 0x28 byte structures */
if (*pDataLen != _CHM_LZXC_RESETTABLE_V1_LEN)
return 0;
/* unmarshal fields */
_unmarshal_uint32 (pData, pDataLen, &dest->version);
_unmarshal_uint32 (pData, pDataLen, &dest->block_count);
_unmarshal_uint32 (pData, pDataLen, &dest->unknown);
_unmarshal_uint32 (pData, pDataLen, &dest->table_offset);
_unmarshal_uint64 (pData, pDataLen, &dest->uncompressed_len);
_unmarshal_uint64 (pData, pDataLen, &dest->compressed_len);
_unmarshal_uint64 (pData, pDataLen, &dest->block_len);
/* check structure */
if (dest->version != 2)
return 0;
return 1;
}
/* structure of LZXC control data block */
#define _CHM_LZXC_MIN_LEN (0x18)
#define _CHM_LZXC_V2_LEN (0x1c)
struct chmLzxcControlData
{
UInt32 size; /* 0 */
char signature[4]; /* 4 (LZXC) */
UInt32 version; /* 8 */
UInt32 resetInterval; /* c */
UInt32 windowSize; /* 10 */
UInt32 windowsPerReset; /* 14 */
UInt32 unknown_18; /* 18 */
};
static int _unmarshal_lzxc_control_data(unsigned char **pData,
unsigned int *pDataLen,
struct chmLzxcControlData *dest)
{
/* we want at least 0x18 bytes */
if (*pDataLen < _CHM_LZXC_MIN_LEN)
return 0;
/* unmarshal fields */
_unmarshal_uint32 (pData, pDataLen, &dest->size);
_unmarshal_char_array(pData, pDataLen, dest->signature, 4);
_unmarshal_uint32 (pData, pDataLen, &dest->version);
_unmarshal_uint32 (pData, pDataLen, &dest->resetInterval);
_unmarshal_uint32 (pData, pDataLen, &dest->windowSize);
_unmarshal_uint32 (pData, pDataLen, &dest->windowsPerReset);
if (*pDataLen >= _CHM_LZXC_V2_LEN)
_unmarshal_uint32 (pData, pDataLen, &dest->unknown_18);
else
dest->unknown_18 = 0;
if (dest->version == 2)
{
dest->resetInterval *= 0x8000;
dest->windowSize *= 0x8000;
}
if (dest->windowSize == 0 || dest->resetInterval == 0)
return 0;
/* for now, only support resetInterval a multiple of windowSize/2 */
if (dest->windowSize == 1)
return 0;
if ((dest->resetInterval % (dest->windowSize/2)) != 0)
return 0;
/* check structure */
if (memcmp(dest->signature, "LZXC", 4) != 0)
return 0;
return 1;
}
/* the structure used for chm file handles */
struct chmFile
{
HANDLE fd;
CRITICAL_SECTION mutex;
CRITICAL_SECTION lzx_mutex;
CRITICAL_SECTION cache_mutex;
UInt64 dir_offset;
UInt64 dir_len;
UInt64 data_offset;
Int32 index_root;
Int32 index_head;
UInt32 block_len;
UInt64 span;
struct chmUnitInfo rt_unit;
struct chmUnitInfo cn_unit;
struct chmLzxcResetTable reset_table;
/* LZX control data */
int compression_enabled;
UInt32 window_size;
UInt32 reset_interval;
UInt32 reset_blkcount;
/* decompressor state */
struct LZXstate *lzx_state;
int lzx_last_block;
/* cache for decompressed blocks */
UChar **cache_blocks;
Int64 *cache_block_indices;
Int32 cache_num_blocks;
};
/*
* utility functions local to this module
*/
/* utility function to handle differences between {pread,read}(64)? */
static Int64 _chm_fetch_bytes(struct chmFile *h,
UChar *buf,
UInt64 os,
Int64 len)
{
Int64 readLen=0;
if (h->fd == CHM_NULL_FD)
return readLen;
CHM_ACQUIRE_LOCK(h->mutex);
/* NOTE: this might be better done with CreateFileMapping, et cetera... */
{
LARGE_INTEGER old_pos, new_pos;
DWORD actualLen=0;
/* awkward Win32 Seek/Tell */
new_pos.QuadPart = 0;
SetFilePointerEx( h->fd, new_pos, &old_pos, FILE_CURRENT );
new_pos.QuadPart = os;
SetFilePointerEx( h->fd, new_pos, NULL, FILE_BEGIN );
/* read the data */
if (ReadFile(h->fd,
buf,
(DWORD)len,
&actualLen,
NULL))
readLen = actualLen;
else
readLen = 0;
/* restore original position */
SetFilePointerEx( h->fd, old_pos, NULL, FILE_BEGIN );
}
CHM_RELEASE_LOCK(h->mutex);
return readLen;
}
/*
* set a parameter on the file handle.
* valid parameter types:
* CHM_PARAM_MAX_BLOCKS_CACHED:
* how many decompressed blocks should be cached? A simple
* caching scheme is used, wherein the index of the block is
* used as a hash value, and hash collision results in the
* invalidation of the previously cached block.
*/
static void chm_set_param(struct chmFile *h,
int paramType,
int paramVal)
{
switch (paramType)
{
case CHM_PARAM_MAX_BLOCKS_CACHED:
CHM_ACQUIRE_LOCK(h->cache_mutex);
if (paramVal != h->cache_num_blocks)
{
UChar **newBlocks;
Int64 *newIndices;
int i;
/* allocate new cached blocks */
newBlocks = HeapAlloc(GetProcessHeap(), 0, paramVal * sizeof (UChar *));
newIndices = HeapAlloc(GetProcessHeap(), 0, paramVal * sizeof (UInt64));
for (i=0; i<paramVal; i++)
{
newBlocks[i] = NULL;
newIndices[i] = 0;
}
/* re-distribute old cached blocks */
if (h->cache_blocks)
{
for (i=0; i<h->cache_num_blocks; i++)
{
int newSlot = (int)(h->cache_block_indices[i] % paramVal);
if (h->cache_blocks[i])
{
/* in case of collision, destroy newcomer */
if (newBlocks[newSlot])
{
HeapFree(GetProcessHeap(), 0, h->cache_blocks[i]);
h->cache_blocks[i] = NULL;
}
else
{
newBlocks[newSlot] = h->cache_blocks[i];
newIndices[newSlot] =
h->cache_block_indices[i];
}
}
}
HeapFree(GetProcessHeap(), 0, h->cache_blocks);
HeapFree(GetProcessHeap(), 0, h->cache_block_indices);
}
/* now, set new values */
h->cache_blocks = newBlocks;
h->cache_block_indices = newIndices;
h->cache_num_blocks = paramVal;
}
CHM_RELEASE_LOCK(h->cache_mutex);
break;
default:
break;
}
}
/* open an ITS archive */
struct chmFile *chm_openW(const WCHAR *filename)
{
unsigned char sbuffer[256];
unsigned int sremain;
unsigned char *sbufpos;
struct chmFile *newHandle=NULL;
struct chmItsfHeader itsfHeader;
struct chmItspHeader itspHeader;
#if 0
struct chmUnitInfo uiSpan;
#endif
struct chmUnitInfo uiLzxc;
struct chmLzxcControlData ctlData;
/* allocate handle */
newHandle = HeapAlloc(GetProcessHeap(), 0, sizeof(struct chmFile));
newHandle->fd = CHM_NULL_FD;
newHandle->lzx_state = NULL;
newHandle->cache_blocks = NULL;
newHandle->cache_block_indices = NULL;
newHandle->cache_num_blocks = 0;
/* open file */
if ((newHandle->fd=CreateFileW(filename,
GENERIC_READ,
FILE_SHARE_READ,
NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL,
NULL)) == CHM_NULL_FD)
{
HeapFree(GetProcessHeap(), 0, newHandle);
return NULL;
}
/* initialize mutexes, if needed */
InitializeCriticalSection(&newHandle->mutex);
newHandle->mutex.DebugInfo->Spare[0] = (DWORD_PTR)(__FILE__ ": chmFile.mutex");
InitializeCriticalSection(&newHandle->lzx_mutex);
newHandle->lzx_mutex.DebugInfo->Spare[0] = (DWORD_PTR)(__FILE__ ": chmFile.lzx_mutex");
InitializeCriticalSection(&newHandle->cache_mutex);
newHandle->cache_mutex.DebugInfo->Spare[0] = (DWORD_PTR)(__FILE__ ": chmFile.cache_mutex");
/* read and verify header */
sremain = _CHM_ITSF_V3_LEN;
sbufpos = sbuffer;
if (_chm_fetch_bytes(newHandle, sbuffer, 0, sremain) != sremain ||
!_unmarshal_itsf_header(&sbufpos, &sremain, &itsfHeader))
{
chm_close(newHandle);
return NULL;
}
/* stash important values from header */
newHandle->dir_offset = itsfHeader.dir_offset;
newHandle->dir_len = itsfHeader.dir_len;
newHandle->data_offset = itsfHeader.data_offset;
/* now, read and verify the directory header chunk */
sremain = _CHM_ITSP_V1_LEN;
sbufpos = sbuffer;
if (_chm_fetch_bytes(newHandle, sbuffer,
itsfHeader.dir_offset, sremain) != sremain ||
!_unmarshal_itsp_header(&sbufpos, &sremain, &itspHeader))
{
chm_close(newHandle);
return NULL;
}
/* grab essential information from ITSP header */
newHandle->dir_offset += itspHeader.header_len;
newHandle->dir_len -= itspHeader.header_len;
newHandle->index_root = itspHeader.index_root;
newHandle->index_head = itspHeader.index_head;
newHandle->block_len = itspHeader.block_len;
/* if the index root is -1, this means we don't have any PMGI blocks.
* as a result, we must use the sole PMGL block as the index root
*/
if (newHandle->index_root == -1)
newHandle->index_root = newHandle->index_head;
/* initialize cache */
chm_set_param(newHandle, CHM_PARAM_MAX_BLOCKS_CACHED,
CHM_MAX_BLOCKS_CACHED);
/* By default, compression is enabled. */
newHandle->compression_enabled = 1;
/* prefetch most commonly needed unit infos */
if (CHM_RESOLVE_SUCCESS != chm_resolve_object(newHandle,
_CHMU_RESET_TABLE,
&newHandle->rt_unit) ||
newHandle->rt_unit.space == CHM_COMPRESSED ||
CHM_RESOLVE_SUCCESS != chm_resolve_object(newHandle,
_CHMU_CONTENT,
&newHandle->cn_unit) ||
newHandle->cn_unit.space == CHM_COMPRESSED ||
CHM_RESOLVE_SUCCESS != chm_resolve_object(newHandle,
_CHMU_LZXC_CONTROLDATA,
&uiLzxc) ||
uiLzxc.space == CHM_COMPRESSED)
{
newHandle->compression_enabled = 0;
}
/* read reset table info */
if (newHandle->compression_enabled)
{
sremain = _CHM_LZXC_RESETTABLE_V1_LEN;
sbufpos = sbuffer;
if (chm_retrieve_object(newHandle, &newHandle->rt_unit, sbuffer,
0, sremain) != sremain ||
!_unmarshal_lzxc_reset_table(&sbufpos, &sremain,
&newHandle->reset_table))
{
newHandle->compression_enabled = 0;
}
}
/* read control data */
if (newHandle->compression_enabled)
{
sremain = (unsigned long)uiLzxc.length;
sbufpos = sbuffer;
if (chm_retrieve_object(newHandle, &uiLzxc, sbuffer,
0, sremain) != sremain ||
!_unmarshal_lzxc_control_data(&sbufpos, &sremain,
&ctlData))
{
newHandle->compression_enabled = 0;
}
newHandle->window_size = ctlData.windowSize;
newHandle->reset_interval = ctlData.resetInterval;
/* Jed, Mon Jun 28: Experimentally, it appears that the reset block count */
/* must be multiplied by this formerly unknown ctrl data field in */
/* order to decompress some files. */
#if 0
newHandle->reset_blkcount = newHandle->reset_interval /
(newHandle->window_size / 2);
#else
newHandle->reset_blkcount = newHandle->reset_interval /
(newHandle->window_size / 2) *
ctlData.windowsPerReset;
#endif
}
return newHandle;
}
/* Duplicate an ITS archive handle */
struct chmFile *chm_dup(struct chmFile *oldHandle)
{
struct chmFile *newHandle=NULL;
newHandle = HeapAlloc(GetProcessHeap(), 0, sizeof(struct chmFile));
*newHandle = *oldHandle;
/* duplicate fd handle */
DuplicateHandle(GetCurrentProcess(), oldHandle->fd,
GetCurrentProcess(), &(newHandle->fd),
0, FALSE, DUPLICATE_SAME_ACCESS);
newHandle->lzx_state = NULL;
newHandle->cache_blocks = NULL;
newHandle->cache_block_indices = NULL;
newHandle->cache_num_blocks = 0;
/* initialize mutexes, if needed */
InitializeCriticalSection(&newHandle->mutex);
newHandle->mutex.DebugInfo->Spare[0] = (DWORD_PTR)(__FILE__ ": chmFile.mutex");
InitializeCriticalSection(&newHandle->lzx_mutex);
newHandle->lzx_mutex.DebugInfo->Spare[0] = (DWORD_PTR)(__FILE__ ": chmFile.lzx_mutex");
InitializeCriticalSection(&newHandle->cache_mutex);
newHandle->cache_mutex.DebugInfo->Spare[0] = (DWORD_PTR)(__FILE__ ": chmFile.cache_mutex");
/* initialize cache */
chm_set_param(newHandle, CHM_PARAM_MAX_BLOCKS_CACHED,
CHM_MAX_BLOCKS_CACHED);
return newHandle;
}
/* close an ITS archive */
void chm_close(struct chmFile *h)
{
if (h != NULL)
{
if (h->fd != CHM_NULL_FD)
CHM_CLOSE_FILE(h->fd);
h->fd = CHM_NULL_FD;
h->mutex.DebugInfo->Spare[0] = 0;
DeleteCriticalSection(&h->mutex);
h->lzx_mutex.DebugInfo->Spare[0] = 0;
DeleteCriticalSection(&h->lzx_mutex);
h->cache_mutex.DebugInfo->Spare[0] = 0;
DeleteCriticalSection(&h->cache_mutex);
if (h->lzx_state)
LZXteardown(h->lzx_state);
h->lzx_state = NULL;
if (h->cache_blocks)
{
int i;
for (i=0; i<h->cache_num_blocks; i++)
{
HeapFree(GetProcessHeap(), 0, h->cache_blocks[i]);
}
HeapFree(GetProcessHeap(), 0, h->cache_blocks);
h->cache_blocks = NULL;
}
HeapFree(GetProcessHeap(), 0, h->cache_block_indices);
h->cache_block_indices = NULL;
HeapFree(GetProcessHeap(), 0, h);
}
}
/*
* helper methods for chm_resolve_object
*/
/* skip a compressed dword */
static void _chm_skip_cword(UChar **pEntry)
{
while (*(*pEntry)++ >= 0x80)
;
}
/* skip the data from a PMGL entry */
static void _chm_skip_PMGL_entry_data(UChar **pEntry)
{
_chm_skip_cword(pEntry);
_chm_skip_cword(pEntry);
_chm_skip_cword(pEntry);
}
/* parse a compressed dword */
static UInt64 _chm_parse_cword(UChar **pEntry)
{
UInt64 accum = 0;
UChar temp;
while ((temp=*(*pEntry)++) >= 0x80)
{
accum <<= 7;
accum += temp & 0x7f;
}
return (accum << 7) + temp;
}
/* parse a utf-8 string into an ASCII char buffer */
static int _chm_parse_UTF8(UChar **pEntry, UInt64 count, WCHAR *path)
{
/* MJM - Modified to return real Unicode strings */
while (count != 0)
{
*path++ = (*(*pEntry)++);
--count;
}
*path = '\0';
return 1;
}
/* parse a PMGL entry into a chmUnitInfo struct; return 1 on success. */
static int _chm_parse_PMGL_entry(UChar **pEntry, struct chmUnitInfo *ui)
{
UInt64 strLen;
/* parse str len */
strLen = _chm_parse_cword(pEntry);
if (strLen > CHM_MAX_PATHLEN)
return 0;
/* parse path */
if (! _chm_parse_UTF8(pEntry, strLen, ui->path))
return 0;
/* parse info */
ui->space = (int)_chm_parse_cword(pEntry);
ui->start = _chm_parse_cword(pEntry);
ui->length = _chm_parse_cword(pEntry);
return 1;
}
/* find an exact entry in PMGL; return NULL if we fail */
static UChar *_chm_find_in_PMGL(UChar *page_buf,
UInt32 block_len,
const WCHAR *objPath)
{
/* XXX: modify this to do a binary search using the nice index structure
* that is provided for us.
*/
struct chmPmglHeader header;
UInt32 hremain;
UChar *end;
UChar *cur;
UChar *temp;
UInt64 strLen;
WCHAR buffer[CHM_MAX_PATHLEN+1];
/* figure out where to start and end */
cur = page_buf;
hremain = _CHM_PMGL_LEN;
if (! _unmarshal_pmgl_header(&cur, &hremain, &header))
return NULL;
end = page_buf + block_len - (header.free_space);
/* now, scan progressively */
while (cur < end)
{
/* grab the name */
temp = cur;
strLen = _chm_parse_cword(&cur);
if (! _chm_parse_UTF8(&cur, strLen, buffer))
return NULL;
/* check if it is the right name */
if (! strcmpiW(buffer, objPath))
return temp;
_chm_skip_PMGL_entry_data(&cur);
}
return NULL;
}
/* find which block should be searched next for the entry; -1 if no block */
static Int32 _chm_find_in_PMGI(UChar *page_buf,
UInt32 block_len,
const WCHAR *objPath)
{
/* XXX: modify this to do a binary search using the nice index structure
* that is provided for us
*/
struct chmPmgiHeader header;
UInt32 hremain;
int page=-1;
UChar *end;
UChar *cur;
UInt64 strLen;
WCHAR buffer[CHM_MAX_PATHLEN+1];
/* figure out where to start and end */
cur = page_buf;
hremain = _CHM_PMGI_LEN;
if (! _unmarshal_pmgi_header(&cur, &hremain, &header))
return -1;
end = page_buf + block_len - (header.free_space);
/* now, scan progressively */
while (cur < end)
{
/* grab the name */
strLen = _chm_parse_cword(&cur);
if (! _chm_parse_UTF8(&cur, strLen, buffer))
return -1;
/* check if it is the right name */
if (strcmpiW(buffer, objPath) > 0)
return page;
/* load next value for path */
page = (int)_chm_parse_cword(&cur);
}
return page;
}
/* resolve a particular object from the archive */
int chm_resolve_object(struct chmFile *h,
const WCHAR *objPath,
struct chmUnitInfo *ui)
{
/*
* XXX: implement caching scheme for dir pages
*/
Int32 curPage;
/* buffer to hold whatever page we're looking at */
UChar *page_buf = HeapAlloc(GetProcessHeap(), 0, h->block_len);
/* starting page */
curPage = h->index_root;
/* until we have either returned or given up */
while (curPage != -1)
{
/* try to fetch the index page */
if (_chm_fetch_bytes(h, page_buf,
h->dir_offset + (UInt64)curPage*h->block_len,
h->block_len) != h->block_len)
{
HeapFree(GetProcessHeap(), 0, page_buf);
return CHM_RESOLVE_FAILURE;
}
/* now, if it is a leaf node: */
if (memcmp(page_buf, _chm_pmgl_marker, 4) == 0)
{
/* scan block */
UChar *pEntry = _chm_find_in_PMGL(page_buf,
h->block_len,
objPath);
if (pEntry == NULL)
{
HeapFree(GetProcessHeap(), 0, page_buf);
return CHM_RESOLVE_FAILURE;
}
/* parse entry and return */
_chm_parse_PMGL_entry(&pEntry, ui);
HeapFree(GetProcessHeap(), 0, page_buf);
return CHM_RESOLVE_SUCCESS;
}
/* else, if it is a branch node: */
else if (memcmp(page_buf, _chm_pmgi_marker, 4) == 0)
curPage = _chm_find_in_PMGI(page_buf, h->block_len, objPath);
/* else, we are confused. give up. */
else
{
HeapFree(GetProcessHeap(), 0, page_buf);
return CHM_RESOLVE_FAILURE;
}
}
/* didn't find anything. fail. */
HeapFree(GetProcessHeap(), 0, page_buf);
return CHM_RESOLVE_FAILURE;
}
/*
* utility methods for dealing with compressed data
*/
/* get the bounds of a compressed block. return 0 on failure */
static int _chm_get_cmpblock_bounds(struct chmFile *h,
UInt64 block,
UInt64 *start,
Int64 *len)
{
UChar buffer[8], *dummy;
UInt32 remain;
/* for all but the last block, use the reset table */
if (block < h->reset_table.block_count-1)
{
/* unpack the start address */
dummy = buffer;
remain = 8;
if (_chm_fetch_bytes(h, buffer,
h->data_offset
+ h->rt_unit.start
+ h->reset_table.table_offset
+ block*8,
remain) != remain ||
!_unmarshal_uint64(&dummy, &remain, start))
return 0;
/* unpack the end address */
dummy = buffer;
remain = 8;
if (_chm_fetch_bytes(h, buffer,
h->data_offset
+ h->rt_unit.start
+ h->reset_table.table_offset
+ block*8 + 8,
remain) != remain ||
!_unmarshal_int64(&dummy, &remain, len))
return 0;
}
/* for the last block, use the span in addition to the reset table */
else
{
/* unpack the start address */
dummy = buffer;
remain = 8;
if (_chm_fetch_bytes(h, buffer,
h->data_offset
+ h->rt_unit.start
+ h->reset_table.table_offset
+ block*8,
remain) != remain ||
!_unmarshal_uint64(&dummy, &remain, start))
return 0;
*len = h->reset_table.compressed_len;
}
/* compute the length and absolute start address */
*len -= *start;
*start += h->data_offset + h->cn_unit.start;
return 1;
}
/* decompress the block. must have lzx_mutex. */
static Int64 _chm_decompress_block(struct chmFile *h,
UInt64 block,
UChar **ubuffer)
{
UChar *cbuffer = HeapAlloc( GetProcessHeap(), 0,
((unsigned int)h->reset_table.block_len + 6144));
UInt64 cmpStart; /* compressed start */
Int64 cmpLen; /* compressed len */
int indexSlot; /* cache index slot */
UChar *lbuffer; /* local buffer ptr */
UInt32 blockAlign = (UInt32)(block % h->reset_blkcount); /* reset interval align */
UInt32 i; /* local loop index */
/* let the caching system pull its weight! */
if (block - blockAlign <= h->lzx_last_block &&
block >= h->lzx_last_block)
blockAlign = (block - h->lzx_last_block);
/* check if we need previous blocks */
if (blockAlign != 0)
{
/* fetch all required previous blocks since last reset */
for (i = blockAlign; i > 0; i--)
{
UInt32 curBlockIdx = block - i;
/* check if we most recently decompressed the previous block */
if (h->lzx_last_block != curBlockIdx)
{
if ((curBlockIdx % h->reset_blkcount) == 0)
{
#ifdef CHM_DEBUG
fprintf(stderr, "***RESET (1)***\n");
#endif
LZXreset(h->lzx_state);
}
indexSlot = (int)((curBlockIdx) % h->cache_num_blocks);
h->cache_block_indices[indexSlot] = curBlockIdx;
if (! h->cache_blocks[indexSlot])
h->cache_blocks[indexSlot] =
HeapAlloc(GetProcessHeap(), 0,
(unsigned int)(h->reset_table.block_len));
lbuffer = h->cache_blocks[indexSlot];
/* decompress the previous block */
#ifdef CHM_DEBUG
fprintf(stderr, "Decompressing block #%4d (EXTRA)\n", curBlockIdx);
#endif
if (!_chm_get_cmpblock_bounds(h, curBlockIdx, &cmpStart, &cmpLen) ||
_chm_fetch_bytes(h, cbuffer, cmpStart, cmpLen) != cmpLen ||
LZXdecompress(h->lzx_state, cbuffer, lbuffer, (int)cmpLen,
(int)h->reset_table.block_len) != DECR_OK)
{
#ifdef CHM_DEBUG
fprintf(stderr, " (DECOMPRESS FAILED!)\n");
#endif
HeapFree(GetProcessHeap(), 0, cbuffer);
return 0;
}
h->lzx_last_block = (int)curBlockIdx;
}
}
}
else
{
if ((block % h->reset_blkcount) == 0)
{
#ifdef CHM_DEBUG
fprintf(stderr, "***RESET (2)***\n");
#endif
LZXreset(h->lzx_state);
}
}
/* allocate slot in cache */
indexSlot = (int)(block % h->cache_num_blocks);
h->cache_block_indices[indexSlot] = block;
if (! h->cache_blocks[indexSlot])
h->cache_blocks[indexSlot] =
HeapAlloc(GetProcessHeap(), 0, ((unsigned int)h->reset_table.block_len));
lbuffer = h->cache_blocks[indexSlot];
*ubuffer = lbuffer;
/* decompress the block we actually want */
#ifdef CHM_DEBUG
fprintf(stderr, "Decompressing block #%4d (REAL )\n", block);
#endif
if (! _chm_get_cmpblock_bounds(h, block, &cmpStart, &cmpLen) ||
_chm_fetch_bytes(h, cbuffer, cmpStart, cmpLen) != cmpLen ||
LZXdecompress(h->lzx_state, cbuffer, lbuffer, (int)cmpLen,
(int)h->reset_table.block_len) != DECR_OK)
{
#ifdef CHM_DEBUG
fprintf(stderr, " (DECOMPRESS FAILED!)\n");
#endif
HeapFree(GetProcessHeap(), 0, cbuffer);
return 0;
}
h->lzx_last_block = (int)block;
/* XXX: modify LZX routines to return the length of the data they
* decompressed and return that instead, for an extra sanity check.
*/
HeapFree(GetProcessHeap(), 0, cbuffer);
return h->reset_table.block_len;
}
/* grab a region from a compressed block */
static Int64 _chm_decompress_region(struct chmFile *h,
UChar *buf,
UInt64 start,
Int64 len)
{
UInt64 nBlock, nOffset;
UInt64 nLen;
UInt64 gotLen;
UChar *ubuffer = NULL;
if (len <= 0)
return 0;
/* figure out what we need to read */
nBlock = start / h->reset_table.block_len;
nOffset = start % h->reset_table.block_len;
nLen = len;
if (nLen > (h->reset_table.block_len - nOffset))
nLen = h->reset_table.block_len - nOffset;
/* if block is cached, return data from it. */
CHM_ACQUIRE_LOCK(h->lzx_mutex);
CHM_ACQUIRE_LOCK(h->cache_mutex);
if (h->cache_block_indices[nBlock % h->cache_num_blocks] == nBlock &&
h->cache_blocks[nBlock % h->cache_num_blocks] != NULL)
{
memcpy(buf,
h->cache_blocks[nBlock % h->cache_num_blocks] + nOffset,
(unsigned int)nLen);
CHM_RELEASE_LOCK(h->cache_mutex);
CHM_RELEASE_LOCK(h->lzx_mutex);
return nLen;
}
CHM_RELEASE_LOCK(h->cache_mutex);
/* data request not satisfied, so... start up the decompressor machine */
if (! h->lzx_state)
{
int window_size = ffs(h->window_size) - 1;
h->lzx_last_block = -1;
h->lzx_state = LZXinit(window_size);
}
/* decompress some data */
gotLen = _chm_decompress_block(h, nBlock, &ubuffer);
if (gotLen < nLen)
nLen = gotLen;
memcpy(buf, ubuffer+nOffset, (unsigned int)nLen);
CHM_RELEASE_LOCK(h->lzx_mutex);
return nLen;
}
/* retrieve (part of) an object */
LONGINT64 chm_retrieve_object(struct chmFile *h,
struct chmUnitInfo *ui,
unsigned char *buf,
LONGUINT64 addr,
LONGINT64 len)
{
/* must be valid file handle */
if (h == NULL)
return 0;
/* starting address must be in correct range */
if (addr >= ui->length)
return 0;
/* clip length */
if (addr + len > ui->length)
len = ui->length - addr;
/* if the file is uncompressed, it's simple */
if (ui->space == CHM_UNCOMPRESSED)
{
/* read data */
return _chm_fetch_bytes(h,
buf,
h->data_offset + ui->start + addr,
len);
}
/* else if the file is compressed, it's a little trickier */
else /* ui->space == CHM_COMPRESSED */
{
Int64 swath=0, total=0;
/* if compression is not enabled for this file... */
if (! h->compression_enabled)
return total;
do {
/* swill another mouthful */
swath = _chm_decompress_region(h, buf, ui->start + addr, len);
/* if we didn't get any... */
if (swath == 0)
return total;
/* update stats */
total += swath;
len -= swath;
addr += swath;
buf += swath;
} while (len != 0);
return total;
}
}
int chm_enumerate_dir(struct chmFile *h,
const WCHAR *prefix,
int what,
CHM_ENUMERATOR e,
void *context)
{
/*
* XXX: do this efficiently (i.e. using the tree index)
*/
Int32 curPage;
/* buffer to hold whatever page we're looking at */
UChar *page_buf = HeapAlloc(GetProcessHeap(), 0, h->block_len);
struct chmPmglHeader header;
UChar *end;
UChar *cur;
unsigned int lenRemain;
/* set to 1 once we've started */
int it_has_begun=0;
/* the current ui */
struct chmUnitInfo ui;
int flag;
UInt64 ui_path_len;
/* the length of the prefix */
WCHAR prefixRectified[CHM_MAX_PATHLEN+1];
int prefixLen;
WCHAR lastPath[CHM_MAX_PATHLEN];
int lastPathLen;
/* starting page */
curPage = h->index_head;
/* initialize pathname state */
lstrcpynW(prefixRectified, prefix, CHM_MAX_PATHLEN);
prefixLen = strlenW(prefixRectified);
if (prefixLen != 0)
{
if (prefixRectified[prefixLen-1] != '/')
{
prefixRectified[prefixLen] = '/';
prefixRectified[prefixLen+1] = '\0';
++prefixLen;
}
}
lastPath[0] = '\0';
lastPathLen = -1;
/* until we have either returned or given up */
while (curPage != -1)
{
/* try to fetch the index page */
if (_chm_fetch_bytes(h,
page_buf,
h->dir_offset + (UInt64)curPage*h->block_len,
h->block_len) != h->block_len)
{
HeapFree(GetProcessHeap(), 0, page_buf);
return 0;
}
/* figure out start and end for this page */
cur = page_buf;
lenRemain = _CHM_PMGL_LEN;
if (! _unmarshal_pmgl_header(&cur, &lenRemain, &header))
{
HeapFree(GetProcessHeap(), 0, page_buf);
return 0;
}
end = page_buf + h->block_len - (header.free_space);
/* loop over this page */
while (cur < end)
{
if (! _chm_parse_PMGL_entry(&cur, &ui))
{
HeapFree(GetProcessHeap(), 0, page_buf);
return 0;
}
/* check if we should start */
if (! it_has_begun)
{
if (ui.length == 0 && strncmpiW(ui.path, prefixRectified, prefixLen) == 0)
it_has_begun = 1;
else
continue;
if (ui.path[prefixLen] == '\0')
continue;
}
/* check if we should stop */
else
{
if (strncmpiW(ui.path, prefixRectified, prefixLen) != 0)
{
HeapFree(GetProcessHeap(), 0, page_buf);
return 1;
}
}
/* check if we should include this path */
if (lastPathLen != -1)
{
if (strncmpiW(ui.path, lastPath, lastPathLen) == 0)
continue;
}
strcpyW(lastPath, ui.path);
lastPathLen = strlenW(lastPath);
/* get the length of the path */
ui_path_len = strlenW(ui.path)-1;
/* check for DIRS */
if (ui.path[ui_path_len] == '/' && !(what & CHM_ENUMERATE_DIRS))
continue;
/* check for FILES */
if (ui.path[ui_path_len] != '/' && !(what & CHM_ENUMERATE_FILES))
continue;
/* check for NORMAL vs. META */
if (ui.path[0] == '/')
{
/* check for NORMAL vs. SPECIAL */
if (ui.path[1] == '#' || ui.path[1] == '$')
flag = CHM_ENUMERATE_SPECIAL;
else
flag = CHM_ENUMERATE_NORMAL;
}
else
flag = CHM_ENUMERATE_META;
if (! (what & flag))
continue;
/* call the enumerator */
{
int status = (*e)(h, &ui, context);
switch (status)
{
case CHM_ENUMERATOR_FAILURE:
HeapFree(GetProcessHeap(), 0, page_buf);
return 0;
case CHM_ENUMERATOR_CONTINUE:
break;
case CHM_ENUMERATOR_SUCCESS:
HeapFree(GetProcessHeap(), 0, page_buf);
return 1;
default:
break;
}
}
}
/* advance to next page */
curPage = header.block_next;
}
HeapFree(GetProcessHeap(), 0, page_buf);
return 1;
}
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