--- /dev/null
+/* MikMod sound library
+ (c) 1998, 1999, 2000, 2001 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.
+*/
+
+/*==============================================================================
+
+ $Id$
+
+ All routines dealing with the manipulation of UNITRK streams
+
+==============================================================================*/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "mikmod_internals.h"
+
+#include <string.h>
+
+/* Unibuffer chunk size */
+#define BUFPAGE 128
+
+const UWORD unioperands[UNI_LAST] = {
+ 0, /* not used */
+ 1, /* UNI_NOTE */
+ 1, /* UNI_INSTRUMENT */
+ 1, /* UNI_PTEFFECT0 */
+ 1, /* UNI_PTEFFECT1 */
+ 1, /* UNI_PTEFFECT2 */
+ 1, /* UNI_PTEFFECT3 */
+ 1, /* UNI_PTEFFECT4 */
+ 1, /* UNI_PTEFFECT5 */
+ 1, /* UNI_PTEFFECT6 */
+ 1, /* UNI_PTEFFECT7 */
+ 1, /* UNI_PTEFFECT8 */
+ 1, /* UNI_PTEFFECT9 */
+ 1, /* UNI_PTEFFECTA */
+ 1, /* UNI_PTEFFECTB */
+ 1, /* UNI_PTEFFECTC */
+ 1, /* UNI_PTEFFECTD */
+ 1, /* UNI_PTEFFECTE */
+ 1, /* UNI_PTEFFECTF */
+ 1, /* UNI_S3MEFFECTA */
+ 1, /* UNI_S3MEFFECTD */
+ 1, /* UNI_S3MEFFECTE */
+ 1, /* UNI_S3MEFFECTF */
+ 1, /* UNI_S3MEFFECTI */
+ 1, /* UNI_S3MEFFECTQ */
+ 1, /* UNI_S3MEFFECTR */
+ 1, /* UNI_S3MEFFECTT */
+ 1, /* UNI_S3MEFFECTU */
+ 0, /* UNI_KEYOFF */
+ 1, /* UNI_KEYFADE */
+ 2, /* UNI_VOLEFFECTS */
+ 1, /* UNI_XMEFFECT4 */
+ 1, /* UNI_XMEFFECT6 */
+ 1, /* UNI_XMEFFECTA */
+ 1, /* UNI_XMEFFECTE1 */
+ 1, /* UNI_XMEFFECTE2 */
+ 1, /* UNI_XMEFFECTEA */
+ 1, /* UNI_XMEFFECTEB */
+ 1, /* UNI_XMEFFECTG */
+ 1, /* UNI_XMEFFECTH */
+ 1, /* UNI_XMEFFECTL */
+ 1, /* UNI_XMEFFECTP */
+ 1, /* UNI_XMEFFECTX1 */
+ 1, /* UNI_XMEFFECTX2 */
+ 1, /* UNI_ITEFFECTG */
+ 1, /* UNI_ITEFFECTH */
+ 1, /* UNI_ITEFFECTI */
+ 1, /* UNI_ITEFFECTM */
+ 1, /* UNI_ITEFFECTN */
+ 1, /* UNI_ITEFFECTP */
+ 1, /* UNI_ITEFFECTT */
+ 1, /* UNI_ITEFFECTU */
+ 1, /* UNI_ITEFFECTW */
+ 1, /* UNI_ITEFFECTY */
+ 2, /* UNI_ITEFFECTZ */
+ 1, /* UNI_ITEFFECTS0 */
+ 2, /* UNI_ULTEFFECT9 */
+ 2, /* UNI_MEDSPEED */
+ 0, /* UNI_MEDEFFECTF1 */
+ 0, /* UNI_MEDEFFECTF2 */
+ 0, /* UNI_MEDEFFECTF3 */
+ 2, /* UNI_OKTARP */
+};
+
+/* Sparse description of the internal module format
+ ------------------------------------------------
+
+ A UNITRK stream is an array of bytes representing a single track of a pattern.
+It's made up of 'repeat/length' bytes, opcodes and operands (sort of a assembly
+language):
+
+rrrlllll
+[REP/LEN][OPCODE][OPERAND][OPCODE][OPERAND] [REP/LEN][OPCODE][OPERAND]..
+^ ^ ^
+|-------ROWS 0 - 0+REP of a track---------| |-------ROWS xx - xx+REP of a track...
+
+ The rep/len byte contains the number of bytes in the current row, _including_
+the length byte itself (So the LENGTH byte of row 0 in the previous example
+would have a value of 5). This makes it easy to search through a stream for a
+particular row. A track is concluded by a 0-value length byte.
+
+ The upper 3 bits of the rep/len byte contain the number of times -1 this row
+is repeated for this track. (so a value of 7 means this row is repeated 8 times)
+
+ Opcodes can range from 1 to 255 but currently only opcodes 1 to 62 are being
+used. Each opcode can have a different number of operands. You can find the
+number of operands to a particular opcode by using the opcode as an index into
+the 'unioperands' table.
+
+*/
+
+/*========== Reading routines */
+
+static UBYTE *rowstart; /* startadress of a row */
+static UBYTE *rowend; /* endaddress of a row (exclusive) */
+static UBYTE *rowpc; /* current unimod(tm) programcounter */
+
+static UBYTE lastbyte; /* for UniSkipOpcode() */
+
+void UniSetRow(UBYTE* t)
+{
+ rowstart = t;
+ rowpc = rowstart;
+ rowend = t?rowstart+(*(rowpc++)&0x1f):t;
+}
+
+UBYTE UniGetByte(void)
+{
+ return lastbyte = (rowpc<rowend)?*(rowpc++):0;
+}
+
+UWORD UniGetWord(void)
+{
+ return ((UWORD)UniGetByte()<<8)|UniGetByte();
+}
+
+void UniSkipOpcode(void)
+{
+ if (lastbyte < UNI_LAST) {
+ UWORD t = unioperands[lastbyte];
+
+ while (t--)
+ UniGetByte();
+ }
+}
+
+/* Finds the address of row number 'row' in the UniMod(tm) stream 't' returns
+ NULL if the row can't be found. */
+UBYTE *UniFindRow(UBYTE* t,UWORD row)
+{
+ UBYTE c,l;
+
+ if(t)
+ while(1) {
+ c = *t; /* get rep/len byte */
+ if(!c) return NULL; /* zero ? -> end of track.. */
+ l = (c>>5)+1; /* extract repeat value */
+ if(l>row) break; /* reached wanted row? -> return pointer */
+ row -= l; /* haven't reached row yet.. update row */
+ t += c&0x1f; /* point t to the next row */
+ }
+ return t;
+}
+
+/*========== Writing routines */
+
+static UBYTE *unibuf; /* pointer to the temporary unitrk buffer */
+static UWORD unimax; /* buffer size */
+
+static UWORD unipc; /* buffer cursor */
+static UWORD unitt; /* current row index */
+static UWORD lastp; /* previous row index */
+
+/* Resets index-pointers to create a new track. */
+void UniReset(void)
+{
+ unitt = 0; /* reset index to rep/len byte */
+ unipc = 1; /* first opcode will be written to index 1 */
+ lastp = 0; /* no previous row yet */
+ unibuf[0] = 0; /* clear rep/len byte */
+}
+
+/* Expands the buffer */
+static BOOL UniExpand(int wanted)
+{
+ if ((unipc+wanted)>=unimax) {
+ UBYTE *newbuf;
+
+ /* Expand the buffer by BUFPAGE bytes */
+ newbuf=(UBYTE*)MikMod_realloc(unibuf,(unimax+BUFPAGE)*sizeof(UBYTE));
+
+ /* Check if MikMod_realloc succeeded */
+ if(newbuf) {
+ unibuf = newbuf;
+ unimax+=BUFPAGE;
+ return 1;
+ } else
+ return 0;
+ }
+ return 1;
+}
+
+/* Appends one byte of data to the current row of a track. */
+void UniWriteByte(UBYTE data)
+{
+ if (UniExpand(1))
+ /* write byte to current position and update */
+ unibuf[unipc++]=data;
+}
+
+void UniWriteWord(UWORD data)
+{
+ if (UniExpand(2)) {
+ unibuf[unipc++]=data>>8;
+ unibuf[unipc++]=data&0xff;
+ }
+}
+
+static BOOL MyCmp(const UBYTE* a,const UBYTE* b,UWORD l)
+{
+ UWORD t;
+
+ for(t=0;t<l;t++)
+ if(*(a++)!=*(b++)) return 0;
+ return 1;
+}
+
+/* Closes the current row of a unitrk stream (updates the rep/len byte) and sets
+ pointers to start a new row. */
+void UniNewline(void)
+{
+ UWORD n,l,len;
+
+ n = (unibuf[lastp]>>5)+1; /* repeat of previous row */
+ l = (unibuf[lastp]&0x1f); /* length of previous row */
+
+ len = unipc-unitt; /* length of current row */
+
+ /* Now, check if the previous and the current row are identical.. when they
+ are, just increase the repeat field of the previous row */
+ if(n<8 && len==l && MyCmp(&unibuf[lastp+1],&unibuf[unitt+1],len-1)) {
+ unibuf[lastp]+=0x20;
+ unipc = unitt+1;
+ } else {
+ if (UniExpand(unitt-unipc)) {
+ /* current and previous row aren't equal... update the pointers */
+ unibuf[unitt] = len;
+ lastp = unitt;
+ unitt = unipc++;
+ }
+ }
+}
+
+/* Terminates the current unitrk stream and returns a pointer to a copy of the
+ stream. */
+UBYTE* UniDup(void)
+{
+ void *d;
+
+ if (!UniExpand(unipc-unitt)) return NULL;
+ unibuf[unitt] = 0;
+
+ if(!(d=MikMod_malloc(unipc))) return NULL;
+ memcpy(d,unibuf,unipc);
+
+ return (UBYTE *)d;
+}
+
+BOOL UniInit(void)
+{
+ unimax = BUFPAGE;
+
+ if(!(unibuf=(UBYTE*)MikMod_malloc(unimax*sizeof(UBYTE)))) return 0;
+ return 1;
+}
+
+void UniCleanup(void)
+{
+ MikMod_free(unibuf);
+ unibuf = NULL;
+}
+
+/* ex:set ts=4: */
projects / dosdemo / blobdiff