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id_ca.cpp
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id_ca.cpp
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// ID_CA.C
// this has been customized for WOLF
/*
=============================================================================
Id Software Caching Manager
---------------------------
Must be started BEFORE the memory manager, because it needs to get the headers
loaded into the data segment
=============================================================================
*/
#include <sys/types.h>
#if defined _WIN32
#include <io.h>
#elif defined _arch_dreamcast
#include <unistd.h>
#else
#include <sys/uio.h>
#include <unistd.h>
#endif
#include "wl_def.h"
#pragma hdrstop
#define THREEBYTEGRSTARTS
/*
=============================================================================
LOCAL CONSTANTS
=============================================================================
*/
typedef struct
{
word bit0,bit1; // 0-255 is a character, > is a pointer to a node
} huffnode;
typedef struct
{
word RLEWtag;
int32_t headeroffsets[100];
} mapfiletype;
/*
=============================================================================
GLOBAL VARIABLES
=============================================================================
*/
#define BUFFERSIZE 0x1000
static int32_t bufferseg[BUFFERSIZE/4];
int mapon;
word *mapsegs[MAPPLANES];
static maptype* mapheaderseg[NUMMAPS];
byte *audiosegs[NUMSNDCHUNKS];
byte *grsegs[NUMCHUNKS];
word RLEWtag;
int numEpisodesMissing = 0;
/*
=============================================================================
LOCAL VARIABLES
=============================================================================
*/
char extension[5]; // Need a string, not constant to change cache files
char graphext[5];
char audioext[5];
static const char gheadname[] = "vgahead.";
static const char gfilename[] = "vgagraph.";
static const char gdictname[] = "vgadict.";
static const char mheadname[] = "maphead.";
static const char mfilename[] = "maptemp.";
static const char aheadname[] = "audiohed.";
static const char afilename[] = "audiot.";
void CA_CannotOpen(const char *string);
static int32_t grstarts[NUMCHUNKS + 1];
static int32_t* audiostarts; // array of offsets in audio / audiot
#ifdef GRHEADERLINKED
huffnode *grhuffman;
#else
huffnode grhuffman[255];
#endif
int grhandle = -1; // handle to EGAGRAPH
int maphandle = -1; // handle to MAPTEMP / GAMEMAPS
int audiohandle = -1; // handle to AUDIOT / AUDIO
int32_t chunkcomplen,chunkexplen;
SDMode oldsoundmode;
static int32_t GRFILEPOS(const size_t idx)
{
assert(idx < lengthof(grstarts));
return grstarts[idx];
}
/*
=============================================================================
LOW LEVEL ROUTINES
=============================================================================
*/
/*
============================
=
= CAL_GetGrChunkLength
=
= Gets the length of an explicit length chunk (not tiles)
= The file pointer is positioned so the compressed data can be read in next.
=
============================
*/
void CAL_GetGrChunkLength (int chunk)
{
lseek(grhandle,GRFILEPOS(chunk),SEEK_SET);
read(grhandle,&chunkexplen,sizeof(chunkexplen));
chunkcomplen = GRFILEPOS(chunk+1)-GRFILEPOS(chunk)-4;
}
/*
==========================
=
= CA_WriteFile
=
= Writes a file from a memory buffer
=
==========================
*/
boolean CA_WriteFile (const char *filename, void *ptr, int32_t length)
{
const int handle = open(filename, O_CREAT | O_WRONLY | O_BINARY, 0644);
if (handle == -1)
return false;
if (!write (handle,ptr,length))
{
close (handle);
return false;
}
close (handle);
return true;
}
/*
==========================
=
= CA_LoadFile
=
= Allocate space for and load a file
=
==========================
*/
boolean CA_LoadFile (const char *filename, memptr *ptr)
{
int32_t size;
const int handle = open(filename, O_RDONLY | O_BINARY);
if (handle == -1)
return false;
size = lseek(handle, 0, SEEK_END);
lseek(handle, 0, SEEK_SET);
*ptr=malloc(size);
CHECKMALLOCRESULT(*ptr);
if (!read (handle,*ptr,size))
{
close (handle);
return false;
}
close (handle);
return true;
}
/*
============================================================================
COMPRESSION routines, see JHUFF.C for more
============================================================================
*/
static void CAL_HuffExpand(byte *source, byte *dest, int32_t length, huffnode *hufftable)
{
byte *end;
huffnode *headptr, *huffptr;
if(!length || !dest)
{
Quit("length or dest is null!");
return;
}
headptr = hufftable+254; // head node is always node 254
int written = 0;
end=dest+length;
byte val = *source++;
byte mask = 1;
word nodeval;
huffptr = headptr;
while(1)
{
if(!(val & mask))
nodeval = huffptr->bit0;
else
nodeval = huffptr->bit1;
if(mask==0x80)
{
val = *source++;
mask = 1;
}
else mask <<= 1;
if(nodeval<256)
{
*dest++ = (byte) nodeval;
written++;
huffptr = headptr;
if(dest>=end) break;
}
else
{
huffptr = hufftable + (nodeval - 256);
}
}
}
/*
======================
=
= CAL_CarmackExpand
=
= Length is the length of the EXPANDED data
=
======================
*/
#define NEARTAG 0xa7
#define FARTAG 0xa8
void CAL_CarmackExpand (byte *source, word *dest, int length)
{
word ch,chhigh,count,offset;
byte *inptr;
word *copyptr, *outptr;
length/=2;
inptr = (byte *) source;
outptr = dest;
while (length>0)
{
ch = READWORD(inptr);
chhigh = ch>>8;
if (chhigh == NEARTAG)
{
count = ch&0xff;
if (!count)
{ // have to insert a word containing the tag byte
ch |= *inptr++;
*outptr++ = ch;
length--;
}
else
{
offset = *inptr++;
copyptr = outptr - offset;
length -= count;
if(length<0) return;
while (count--)
*outptr++ = *copyptr++;
}
}
else if (chhigh == FARTAG)
{
count = ch&0xff;
if (!count)
{ // have to insert a word containing the tag byte
ch |= *inptr++;
*outptr++ = ch;
length --;
}
else
{
offset = READWORD(inptr);
copyptr = dest + offset;
length -= count;
if(length<0) return;
while (count--)
*outptr++ = *copyptr++;
}
}
else
{
*outptr++ = ch;
length --;
}
}
}
/*
======================
=
= CA_RLEWcompress
=
======================
*/
int32_t CA_RLEWCompress (word *source, int32_t length, word *dest, word rlewtag)
{
word value,count;
unsigned i;
word *start,*end;
start = dest;
end = source + (length+1)/2;
//
// compress it
//
do
{
count = 1;
value = *source++;
while (*source == value && source<end)
{
count++;
source++;
}
if (count>3 || value == rlewtag)
{
//
// send a tag / count / value string
//
*dest++ = rlewtag;
*dest++ = count;
*dest++ = value;
}
else
{
//
// send word without compressing
//
for (i=1;i<=count;i++)
*dest++ = value;
}
} while (source<end);
return (int32_t)(2*(dest-start));
}
/*
======================
=
= CA_RLEWexpand
= length is EXPANDED length
=
======================
*/
void CA_RLEWexpand (word *source, word *dest, int32_t length, word rlewtag)
{
word value,count,i;
word *end=dest+length/2;
//
// expand it
//
do
{
value = *source++;
if (value != rlewtag)
//
// uncompressed
//
*dest++=value;
else
{
//
// compressed string
//
count = *source++;
value = *source++;
for (i=1;i<=count;i++)
*dest++ = value;
}
} while (dest<end);
}
/*
=============================================================================
CACHE MANAGER ROUTINES
=============================================================================
*/
/*
======================
=
= CAL_SetupGrFile
=
======================
*/
void CAL_SetupGrFile (void)
{
char fname[13];
int handle;
byte *compseg;
#ifdef GRHEADERLINKED
grhuffman = (huffnode *)&EGAdict;
grstarts = (int32_t _seg *)FP_SEG(&EGAhead);
#else
//
// load ???dict.ext (huffman dictionary for graphics files)
//
strcpy(fname,gdictname);
strcat(fname,graphext);
handle = open(fname, O_RDONLY | O_BINARY);
if (handle == -1)
CA_CannotOpen(fname);
read(handle, grhuffman, sizeof(grhuffman));
close(handle);
// load the data offsets from ???head.ext
strcpy(fname,gheadname);
strcat(fname,graphext);
handle = open(fname, O_RDONLY | O_BINARY);
if (handle == -1)
CA_CannotOpen(fname);
long headersize = lseek(handle, 0, SEEK_END);
lseek(handle, 0, SEEK_SET);
#ifndef APOGEE_1_0
int expectedsize = lengthof(grstarts) - numEpisodesMissing;
#else
int expectedsize = lengthof(grstarts);
#endif
if(!param_ignorenumchunks && headersize / 3 != (long) expectedsize)
Quit("Wolf4SDL was not compiled for these data files:\n"
"%s contains a wrong number of offsets (%i instead of %i)!\n\n"
"Please check whether you are using the right executable!\n"
"(For mod developers: perhaps you forgot to update NUMCHUNKS?)",
fname, headersize / 3, expectedsize);
byte data[lengthof(grstarts) * 3];
read(handle, data, sizeof(data));
close(handle);
const byte* d = data;
for (int32_t* i = grstarts; i != endof(grstarts); ++i)
{
const int32_t val = d[0] | d[1] << 8 | d[2] << 16;
*i = (val == 0x00FFFFFF ? -1 : val);
d += 3;
}
#endif
//
// Open the graphics file, leaving it open until the game is finished
//
strcpy(fname,gfilename);
strcat(fname,graphext);
grhandle = open(fname, O_RDONLY | O_BINARY);
if (grhandle == -1)
CA_CannotOpen(fname);
//
// load the pic and sprite headers into the arrays in the data segment
//
pictable=(pictabletype *) malloc(NUMPICS*sizeof(pictabletype));
CHECKMALLOCRESULT(pictable);
CAL_GetGrChunkLength(STRUCTPIC); // position file pointer
compseg=(byte *) malloc(chunkcomplen);
CHECKMALLOCRESULT(compseg);
read (grhandle,compseg,chunkcomplen);
CAL_HuffExpand(compseg, (byte*)pictable, NUMPICS * sizeof(pictabletype), grhuffman);
free(compseg);
}
//==========================================================================
/*
======================
=
= CAL_SetupMapFile
=
======================
*/
void CAL_SetupMapFile (void)
{
int i;
int handle;
int32_t length,pos;
char fname[13];
//
// load maphead.ext (offsets and tileinfo for map file)
//
strcpy(fname,mheadname);
strcat(fname,extension);
handle = open(fname, O_RDONLY | O_BINARY);
if (handle == -1)
CA_CannotOpen(fname);
length = NUMMAPS*4+2; // used to be "filelength(handle);"
mapfiletype *tinf=(mapfiletype *) malloc(sizeof(mapfiletype));
CHECKMALLOCRESULT(tinf);
read(handle, tinf, length);
close(handle);
RLEWtag=tinf->RLEWtag;
//
// open the data file
//
#ifdef CARMACIZED
strcpy(fname, "gamemaps.");
strcat(fname, extension);
maphandle = open(fname, O_RDONLY | O_BINARY);
if (maphandle == -1)
CA_CannotOpen(fname);
#else
strcpy(fname,mfilename);
strcat(fname,extension);
maphandle = open(fname, O_RDONLY | O_BINARY);
if (maphandle == -1)
CA_CannotOpen(fname);
#endif
//
// load all map header
//
for (i=0;i<NUMMAPS;i++)
{
pos = tinf->headeroffsets[i];
if (pos<0) // $FFFFFFFF start is a sparse map
continue;
mapheaderseg[i]=(maptype *) malloc(sizeof(maptype));
CHECKMALLOCRESULT(mapheaderseg[i]);
lseek(maphandle,pos,SEEK_SET);
read (maphandle,(memptr)mapheaderseg[i],sizeof(maptype));
}
free(tinf);
//
// allocate space for 3 64*64 planes
//
for (i=0;i<MAPPLANES;i++)
{
mapsegs[i]=(word *) malloc(maparea*2);
CHECKMALLOCRESULT(mapsegs[i]);
}
}
//==========================================================================
/*
======================
=
= CAL_SetupAudioFile
=
======================
*/
void CAL_SetupAudioFile (void)
{
char fname[13];
//
// load audiohed.ext (offsets for audio file)
//
strcpy(fname,aheadname);
strcat(fname,audioext);
void* ptr;
if (!CA_LoadFile(fname, &ptr))
CA_CannotOpen(fname);
audiostarts = (int32_t*)ptr;
//
// open the data file
//
strcpy(fname,afilename);
strcat(fname,audioext);
audiohandle = open(fname, O_RDONLY | O_BINARY);
if (audiohandle == -1)
CA_CannotOpen(fname);
}
//==========================================================================
/*
======================
=
= CA_Startup
=
= Open all files and load in headers
=
======================
*/
void CA_Startup (void)
{
#ifdef PROFILE
unlink ("PROFILE.TXT");
profilehandle = open("PROFILE.TXT", O_CREAT | O_WRONLY | O_TEXT);
#endif
CAL_SetupMapFile ();
CAL_SetupGrFile ();
CAL_SetupAudioFile ();
mapon = -1;
}
//==========================================================================
/*
======================
=
= CA_Shutdown
=
= Closes all files
=
======================
*/
void CA_Shutdown (void)
{
int i,start;
if(maphandle != -1)
close(maphandle);
if(grhandle != -1)
close(grhandle);
if(audiohandle != -1)
close(audiohandle);
for(i=0; i<NUMCHUNKS; i++)
UNCACHEGRCHUNK(i);
free(pictable);
switch(oldsoundmode)
{
case sdm_Off:
return;
case sdm_PC:
start = STARTPCSOUNDS;
break;
case sdm_AdLib:
start = STARTADLIBSOUNDS;
break;
}
for(i=0; i<NUMSOUNDS; i++,start++)
UNCACHEAUDIOCHUNK(start);
}
//===========================================================================
/*
======================
=
= CA_CacheAudioChunk
=
======================
*/
int32_t CA_CacheAudioChunk (int chunk)
{
int32_t pos = audiostarts[chunk];
int32_t size = audiostarts[chunk+1]-pos;
if (audiosegs[chunk])
return size; // already in memory
audiosegs[chunk]=(byte *) malloc(size);
CHECKMALLOCRESULT(audiosegs[chunk]);
lseek(audiohandle,pos,SEEK_SET);
read(audiohandle,audiosegs[chunk],size);
return size;
}
void CA_CacheAdlibSoundChunk (int chunk)
{
int32_t pos = audiostarts[chunk];
int32_t size = audiostarts[chunk+1]-pos;
if (audiosegs[chunk])
return; // already in memory
lseek(audiohandle, pos, SEEK_SET);
read(audiohandle, bufferseg, ORIG_ADLIBSOUND_SIZE - 1); // without data[1]
AdLibSound *sound = (AdLibSound *) malloc(size + sizeof(AdLibSound) - ORIG_ADLIBSOUND_SIZE);
CHECKMALLOCRESULT(sound);
byte *ptr = (byte *) bufferseg;
sound->common.length = READLONGWORD(ptr);
sound->common.priority = READWORD(ptr);
sound->inst.mChar = *ptr++;
sound->inst.cChar = *ptr++;
sound->inst.mScale = *ptr++;
sound->inst.cScale = *ptr++;
sound->inst.mAttack = *ptr++;
sound->inst.cAttack = *ptr++;
sound->inst.mSus = *ptr++;
sound->inst.cSus = *ptr++;
sound->inst.mWave = *ptr++;
sound->inst.cWave = *ptr++;
sound->inst.nConn = *ptr++;
sound->inst.voice = *ptr++;
sound->inst.mode = *ptr++;
sound->inst.unused[0] = *ptr++;
sound->inst.unused[1] = *ptr++;
sound->inst.unused[2] = *ptr++;
sound->block = *ptr++;
read(audiohandle, sound->data, size - ORIG_ADLIBSOUND_SIZE + 1); // + 1 because of byte data[1]
audiosegs[chunk]=(byte *) sound;
}
//===========================================================================
/*
======================
=
= CA_LoadAllSounds
=
= Purges all sounds, then loads all new ones (mode switch)
=
======================
*/
void CA_LoadAllSounds (void)
{
unsigned start,i;
switch (oldsoundmode)
{
case sdm_Off:
goto cachein;
case sdm_PC:
start = STARTPCSOUNDS;
break;
case sdm_AdLib:
start = STARTADLIBSOUNDS;
break;
}
for (i=0;i<NUMSOUNDS;i++,start++)
UNCACHEAUDIOCHUNK(start);
cachein:
oldsoundmode = SoundMode;
switch (SoundMode)
{
case sdm_Off:
start = STARTADLIBSOUNDS; // needed for priorities...
break;
case sdm_PC:
start = STARTPCSOUNDS;
break;
case sdm_AdLib:
start = STARTADLIBSOUNDS;
break;
}
if(start == STARTADLIBSOUNDS)
{
for (i=0;i<NUMSOUNDS;i++,start++)
CA_CacheAdlibSoundChunk(start);
}
else
{
for (i=0;i<NUMSOUNDS;i++,start++)
CA_CacheAudioChunk(start);
}
}
//===========================================================================
/*
======================
=
= CAL_ExpandGrChunk
=
= Does whatever is needed with a pointer to a compressed chunk
=
======================
*/
void CAL_ExpandGrChunk (int chunk, int32_t *source)
{
int32_t expanded;
if (chunk >= STARTTILE8 && chunk < STARTEXTERNS)
{
//
// expanded sizes of tile8/16/32 are implicit
//
#define BLOCK 64
#define MASKBLOCK 128
if (chunk<STARTTILE8M) // tile 8s are all in one chunk!
expanded = BLOCK*NUMTILE8;
else if (chunk<STARTTILE16)
expanded = MASKBLOCK*NUMTILE8M;
else if (chunk<STARTTILE16M) // all other tiles are one/chunk
expanded = BLOCK*4;
else if (chunk<STARTTILE32)
expanded = MASKBLOCK*4;
else if (chunk<STARTTILE32M)
expanded = BLOCK*16;
else
expanded = MASKBLOCK*16;
}
else
{
//
// everything else has an explicit size longword
//
expanded = *source++;
}
//
// allocate final space, decompress it, and free bigbuffer
// Sprites need to have shifts made and various other junk
//
grsegs[chunk]=(byte *) malloc(expanded);
CHECKMALLOCRESULT(grsegs[chunk]);
CAL_HuffExpand((byte *) source, grsegs[chunk], expanded, grhuffman);
}
/*
======================
=
= CA_CacheGrChunk
=
= Makes sure a given chunk is in memory, loadiing it if needed
=
======================
*/
void CA_CacheGrChunk (int chunk)
{
int32_t pos,compressed;
int32_t *source;
int next;
if (grsegs[chunk])
return; // already in memory
//
// load the chunk into a buffer, either the miscbuffer if it fits, or allocate
// a larger buffer
//
pos = GRFILEPOS(chunk);
if (pos<0) // $FFFFFFFF start is a sparse tile
return;
next = chunk +1;
while (GRFILEPOS(next) == -1) // skip past any sparse tiles
next++;
compressed = GRFILEPOS(next)-pos;
lseek(grhandle,pos,SEEK_SET);
if (compressed<=BUFFERSIZE)
{
read(grhandle,bufferseg,compressed);
source = bufferseg;
}
else
{
source = (int32_t *) malloc(compressed);
CHECKMALLOCRESULT(source);
read(grhandle,source,compressed);
}
CAL_ExpandGrChunk (chunk,source);
if (compressed>BUFFERSIZE)
free(source);
}
//==========================================================================
/*
======================
=
= CA_CacheScreen
=
= Decompresses a chunk from disk straight onto the screen
=
======================
*/
void CA_CacheScreen (int chunk)
{
int32_t pos,compressed,expanded;
memptr bigbufferseg;
int32_t *source;
int next;
byte *pic, *vbuf;
int x, y, scx, scy;
unsigned i, j;
//
// load the chunk into a buffer
//
pos = GRFILEPOS(chunk);
next = chunk +1;
while (GRFILEPOS(next) == -1) // skip past any sparse tiles
next++;
compressed = GRFILEPOS(next)-pos;
lseek(grhandle,pos,SEEK_SET);
bigbufferseg=malloc(compressed);
CHECKMALLOCRESULT(bigbufferseg);
read(grhandle,bigbufferseg,compressed);
source = (int32_t *) bigbufferseg;