/*
** routines for reading and writing dx7 voices
*/

#include <stdio.h>
#include <midi.h>
#include <dx7voice.h>

/* Need a header & trailer in dx7 file for da(1) */
static char header[6] = {SX_CMD,ID_DX7,0,0,1,0x1b};
static char trailer[2] = {0x42,SX_EOB}; /* random checksum & end of block */

char dx7CheckSum();

Dx7Voice *
dx7readVoice(f, name)
	FILE *f;
	char *name; /* filename (used only in diagnostics) */
/*
** Read a 'Dx7Voice' from 'f' and return it,
** or NULL if there was a problem.
** The 'Dx7Voice' is expected to be 155 hex bytes.
** Should probably understand alternate formats,
** like `da`(1) output, C-style format, etc.
*/
{
	Dx7Voice *v = Alloc(Dx7Voice);
#define	n SizeofDx7Voice
	if (!v) return MidiError("dx7readDx7Voice(%s): no memory.\n",name),v;
	if (read(fileno(f),v,sizeof header) != sizeof(header) ||
	    read(fileno(f),v,n) != n)
	   MidiError("dx7readVoice(%s): byte count error\n",name),
	   v = (Dx7Voice *)0;
	else
	   v->name[10] = '\0';
	return v;
#undef n
}

Dx7Voice *
dx7ReadVoice(name)
	char *name;
/*
** Read a 'Dx7Voice' from the file 'name' and return it,
** or NULL if there was a problem.  See 'readDx7Voice()'.
*/
{
	FILE *f = fopen(name,"r");
	Dx7Voice *v;

	if (!f) return MidiError("dx7ReadVoice: can't open '%s'\n",name),
		       (Dx7Voice *)0;
	v = dx7readVoice(f,name);
	fclose(f);
	return v;
}

dx7writeVoice(v,f)
	Dx7Voice *v;
	FILE *f;
/*
** Write 'v' to 'f',
** Return 1 if successful, 0 if not.
** Should perhaps accommodate different formats (C, da).
** As it is, just writes out 155 hex bytes.
*/
{
	int r;
	write(fileno(f),header,sizeof header),
	r = write(fileno(f),v,SizeofDx7Voice)==SizeofDx7Voice;
	trailer[0] = dx7CheckSum(v);
	write(fileno(f),trailer,sizeof trailer);
	return r;
}

dx7WriteVoice(v,name)
	Dx7Voice *v;
	char *name;
/*
** Write 'v' to the file called 'name'.
** Return 1 if successful, 0 if not.
*/
{
	FILE *f = fopen(name,"w");
	int r=0;
	if (f) r=dx7writeVoice(v,f),fclose(f);
	else MidiError("dx7WriteVoice: couldn't write on '%s'\n",name);
	return r;
}

/*
main(){
	Dx7Voice *v = dx7ReadVoice("flute");
	if (v) dx7WriteVoice(v,"wingo");
}
*/