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Member "libmikmod-3.2.0/loaders/load_m15.c" of archive libmikmod-3.2.0.tar.gz:
/* MikMod sound library
(c) 1998, 1999, 2000, 2001, 2002 Miodrag Vallat and others - see file
AUTHORS for complete list.
This library is free software; you can redistribute it and/or modify
it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of
the License, or (at your option) any later version.
This program 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 Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA.
*/
/*==============================================================================
$Id$
15 instrument MOD loader
Also supports Ultimate Sound Tracker (old M15 format)
==============================================================================*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <ctype.h>
#include <stdio.h>
#ifdef HAVE_MEMORY_H
#include <memory.h>
#endif
#include <string.h>
#include "mikmod_internals.h"
#ifdef SUNOS
extern int fprintf(FILE *, const char *, ...);
#endif
/*========== Module Structure */
typedef struct MSAMPINFO {
CHAR samplename[23]; /* 22 in module, 23 in memory */
UWORD length;
UBYTE finetune;
UBYTE volume;
UWORD reppos;
UWORD replen;
} MSAMPINFO;
typedef struct MODULEHEADER {
CHAR songname[21]; /* the songname.., 20 in module, 21 in memory */
MSAMPINFO samples[15]; /* all sampleinfo */
UBYTE songlength; /* number of patterns used */
UBYTE magic1; /* should be 127 */
UBYTE positions[128]; /* which pattern to play at pos */
} MODULEHEADER;
typedef struct MODNOTE {
UBYTE a,b,c,d;
} MODNOTE;
/*========== Loader variables */
static MODULEHEADER *mh = NULL;
static MODNOTE *patbuf = NULL;
static BOOL ust_loader = 0; /* if TRUE, load as an ust module. */
/* known file formats which can confuse the loader */
#define REJECT 2
static char *signatures[REJECT]={
"CAKEWALK", /* cakewalk midi files */
"SZDD" /* Microsoft compressed files */
};
static int siglen[REJECT]={8,4};
/*========== Loader code */
static BOOL LoadModuleHeader(MODULEHEADER *mh)
{
int t,u;
_mm_read_string(mh->songname,20,modreader);
mh->songname[20]=0; /* just in case */
/* sanity check : title should contain printable characters and a bunch
of null chars */
for(t=0;t<20;t++)
if((mh->songname[t])&&(mh->songname[t]<32)) return 0;
for(t=0;(mh->songname[t])&&(t<20);t++);
if(t<20) for(;t<20;t++) if(mh->songname[t]) return 0;
for(t=0;t<15;t++) {
MSAMPINFO *s=&mh->samples[t];
_mm_read_string(s->samplename,22,modreader);
s->samplename[22]=0; /* just in case */
s->length =_mm_read_M_UWORD(modreader);
s->finetune =_mm_read_UBYTE(modreader);
s->volume =_mm_read_UBYTE(modreader);
s->reppos =_mm_read_M_UWORD(modreader);
s->replen =_mm_read_M_UWORD(modreader);
/* sanity check : sample title should contain printable characters and
a bunch of null chars */
for(u=0;u<20;u++)
if((s->samplename[u])&&(s->samplename[u]</*32*/14)) return 0;
for(u=0;(s->samplename[u])&&(u<20);u++);
if(u<20) for(;u<20;u++) if(s->samplename[u]) return 0;
/* sanity check : finetune values */
if(s->finetune>>4) return 0;
}
mh->songlength =_mm_read_UBYTE(modreader);
mh->magic1 =_mm_read_UBYTE(modreader); /* should be 127 */
/* sanity check : no more than 128 positions, restart position in range */
if((!mh->songlength)||(mh->songlength>128)) return 0;
/* values encountered so far are 0x6a and 0x78 */
if(((mh->magic1&0xf8)!=0x78)&&(mh->magic1!=0x6a)&&(mh->magic1>mh->songlength)) return 0;
_mm_read_UBYTES(mh->positions,128,modreader);
/* sanity check : pattern range is 0..63 */
for(t=0;t<128;t++)
if(mh->positions[t]>63) return 0;
return(!_mm_eof(modreader));
}
/* Checks the patterns in the modfile for UST / 15-inst indications.
For example, if an effect 3xx is found, it is assumed that the song
is 15-inst. If a 1xx effect has dat greater than 0x20, it is UST.
Returns: 0 indecisive; 1 = UST; 2 = 15-inst */
static int CheckPatternType(int numpat)
{
int t;
UBYTE eff, dat;
for(t=0;t<numpat*(64U*4);t++) {
/* Load the pattern into the temp buffer and scan it */
_mm_read_UBYTE(modreader);_mm_read_UBYTE(modreader);
eff = _mm_read_UBYTE(modreader);
dat = _mm_read_UBYTE(modreader);
switch(eff) {
case 1:
if(dat>0x1f) return 1;
if(dat<0x3) return 2;
break;
case 2:
if(dat>0x1f) return 1;
return 2;
case 3:
if (dat) return 2;
break;
default:
return 2;
}
}
return 0;
}
static BOOL M15_Test(void)
{
int t, numpat;
MODULEHEADER mh;
ust_loader = 0;
if(!LoadModuleHeader(&mh)) return 0;
/* reject other file types */
for(t=0;t<REJECT;t++)
if(!memcmp(mh.songname,signatures[t],siglen[t])) return 0;
if(mh.magic1>127) return 0;
if((!mh.songlength)||(mh.songlength>mh.magic1)) return 0;
for(t=0;t<15;t++) {
/* all finetunes should be zero */
if(mh.samples[t].finetune) return 0;
/* all volumes should be <= 64 */
if(mh.samples[t].volume>64) return 0;
/* all instrument names should begin with s, st-, or a number */
if((mh.samples[t].samplename[0]=='s')||
(mh.samples[t].samplename[0]=='S')) {
if((memcmp(mh.samples[t].samplename,"st-",3)) &&
(memcmp(mh.samples[t].samplename,"ST-",3)) &&
(*mh.samples[t].samplename))
ust_loader = 1;
} else
if(!isdigit((int)mh.samples[t].samplename[0]))
ust_loader = 1;
if(mh.samples[t].length>4999||mh.samples[t].reppos>9999) {
ust_loader = 0;
if(mh.samples[t].length>32768) return 0;
}
/* if loop information is incorrect as words, but correct as bytes,
this is likely to be an ust-style module */
if((mh.samples[t].reppos+mh.samples[t].replen>mh.samples[t].length)&&
(mh.samples[t].reppos+mh.samples[t].replen<(mh.samples[t].length<<1))){
ust_loader = 1;
return 1;
}
if(!ust_loader) return 1;
}
for(numpat=0,t=0;t<mh.songlength;t++)
if(mh.positions[t]>numpat)
numpat = mh.positions[t];
numpat++;
switch(CheckPatternType(numpat)) {
case 0: /* indecisive, so check more clues... */
break;
case 1:
ust_loader = 1;
break;
case 2:
ust_loader = 0;
break;
}
return 1;
}
static BOOL M15_Init(void)
{
if(!(mh=(MODULEHEADER*)MikMod_malloc(sizeof(MODULEHEADER)))) return 0;
return 1;
}
static void M15_Cleanup(void)
{
MikMod_free(mh);
MikMod_free(patbuf);
}
/*
Old (amiga) noteinfo:
_____byte 1_____ byte2_ _____byte 3_____ byte4_
/ \ / \ / \ / \
0000 0000-00000000 0000 0000-00000000
Upper four 12 bits for Lower four Effect command.
bits of sam- note period. bits of sam-
ple number. ple number.
*/
static UBYTE M15_ConvertNote(MODNOTE* n, UBYTE lasteffect)
{
UBYTE instrument,effect,effdat,note;
UWORD period;
UBYTE lastnote=0;
/* decode the 4 bytes that make up a single note */
instrument = n->c>>4;
period = (((UWORD)n->a&0xf)<<8)+n->b;
effect = n->c&0xf;
effdat = n->d;
/* Convert the period to a note number */
note=0;
if(period) {
for(note=0;note<7*OCTAVE;note++)
if(period>=npertab[note]) break;
if(note==7*OCTAVE) note=0;
else note++;
}
if(instrument) {
/* if instrument does not exist, note cut */
if((instrument>15)||(!mh->samples[instrument-1].length)) {
UniPTEffect(0xc,0);
if(effect==0xc) effect=effdat=0;
} else {
/* if we had a note, then change instrument... */
if(note)
UniInstrument(instrument-1);
/* ...otherwise, only adjust volume... */
else {
/* ...unless an effect was specified, which forces a new note
to be played */
if(effect||effdat) {
UniInstrument(instrument-1);
note=lastnote;
} else
UniPTEffect(0xc,mh->samples[instrument-1].volume&0x7f);
}
}
}
if(note) {
UniNote(note+2*OCTAVE-1);
lastnote=note;
}
/* Convert pattern jump from Dec to Hex */
if(effect == 0xd)
effdat=(((effdat&0xf0)>>4)*10)+(effdat&0xf);
/* Volume slide, up has priority */
if((effect==0xa)&&(effdat&0xf)&&(effdat&0xf0))
effdat&=0xf0;
/* Handle ``heavy'' volumes correctly */
if ((effect == 0xc) && (effdat > 0x40))
effdat = 0x40;
if(ust_loader) {
switch(effect) {
case 0:
case 3:
break;
case 1:
UniPTEffect(0,effdat);
break;
case 2:
if(effdat&0xf) UniPTEffect(1,effdat&0xf);
else if(effdat>>2) UniPTEffect(2,effdat>>2);
break;
default:
UniPTEffect(effect,effdat);
break;
}
} else {
/* An isolated 100, 200 or 300 effect should be ignored (no
"standalone" porta memory in mod files). However, a sequence
such as 1XX, 100, 100, 100 is fine. */
if ((!effdat) && ((effect == 1)||(effect == 2)||(effect ==3)) &&
(lasteffect < 0x10) && (effect != lasteffect))
effect = 0;
UniPTEffect(effect,effdat);
}
if (effect == 8)
of.flags |= UF_PANNING;
return effect;
}
static UBYTE *M15_ConvertTrack(MODNOTE* n)
{
int t;
UBYTE lasteffect = 0x10; /* non existant effect */
UniReset();
for(t=0;t<64;t++) {
lasteffect = M15_ConvertNote(n,lasteffect);
UniNewline();
n+=4;
}
return UniDup();
}
/* Loads all patterns of a modfile and converts them into the 3 byte format. */
static BOOL M15_LoadPatterns(void)
{
int t,s,tracks=0;
if(!AllocPatterns()) return 0;
if(!AllocTracks()) return 0;
/* Allocate temporary buffer for loading and converting the patterns */
if(!(patbuf=(MODNOTE*)MikMod_calloc(64U*4,sizeof(MODNOTE)))) return 0;
for(t=0;t<of.numpat;t++) {
/* Load the pattern into the temp buffer and convert it */
for(s=0;s<(64U*4);s++) {
patbuf[s].a=_mm_read_UBYTE(modreader);
patbuf[s].b=_mm_read_UBYTE(modreader);
patbuf[s].c=_mm_read_UBYTE(modreader);
patbuf[s].d=_mm_read_UBYTE(modreader);
}
for(s=0;s<4;s++)
if(!(of.tracks[tracks++]=M15_ConvertTrack(patbuf+s))) return 0;
}
return 1;
}
static BOOL M15_Load(BOOL curious)
{
int t,scan;
SAMPLE *q;
MSAMPINFO *s;
/* try to read module header */
if(!LoadModuleHeader(mh)) {
_mm_errno = MMERR_LOADING_HEADER;
return 0;
}
if(ust_loader)
of.modtype = StrDup("Ultimate Soundtracker");
else
of.modtype = StrDup("Soundtracker");
/* set module variables */
of.initspeed = 6;
of.inittempo = 125;
of.numchn = 4;
of.songname = DupStr(mh->songname,21,1);
of.numpos = mh->songlength;
of.reppos = 0;
/* Count the number of patterns */
of.numpat = 0;
for(t=0;t<of.numpos;t++)
if(mh->positions[t]>of.numpat)
of.numpat=mh->positions[t];
/* since some old modules embed extra patterns, we have to check the
whole list to get the samples' file offsets right - however we can find
garbage here, so check carefully */
scan=1;
for(t=of.numpos;t<128;t++)
if(mh->positions[t]>=0x80) scan=0;
if (scan)
for(t=of.numpos;t<128;t++) {
if(mh->positions[t]>of.numpat)
of.numpat=mh->positions[t];
if((curious)&&(mh->positions[t])) of.numpos=t+1;
}
of.numpat++;
of.numtrk = of.numpat*of.numchn;
if(!AllocPositions(of.numpos)) return 0;
for(t=0;t<of.numpos;t++)
of.positions[t]=mh->positions[t];
/* Finally, init the sampleinfo structures */
of.numins=of.numsmp=15;
if(!AllocSamples()) return 0;
s = mh->samples;
q = of.samples;
for(t=0;t<of.numins;t++) {
/* convert the samplename */
q->samplename = DupStr(s->samplename,23,1);
/* init the sampleinfo variables and convert the size pointers */
q->speed = finetune[s->finetune&0xf];
q->volume = s->volume;
if(ust_loader)
q->loopstart = s->reppos;
else
q->loopstart = s->reppos<<1;
q->loopend = q->loopstart+(s->replen<<1);
q->length = s->length<<1;
q->flags = SF_SIGNED;
if(ust_loader) q->flags |= SF_UST_LOOP;
if(s->replen>2) q->flags |= SF_LOOP;
s++;
q++;
}
if(!M15_LoadPatterns()) return 0;
ust_loader = 0;
return 1;
}
static CHAR *M15_LoadTitle(void)
{
CHAR s[21];
_mm_fseek(modreader,0,SEEK_SET);
if(!_mm_read_UBYTES(s,20,modreader)) return NULL;
s[20]=0; /* just in case */
return(DupStr(s,21,1));
}
/*========== Loader information */
MIKMODAPI MLOADER load_m15={
NULL,
"15-instrument module",
"MOD (15 instrument)",
M15_Init,
M15_Test,
M15_Load,
M15_Cleanup,
M15_LoadTitle
};
/* ex:set ts=4: */