summaryrefslogtreecommitdiff
path: root/qmpmidiread.cpp
blob: 0bcf59759d4cb7b4706208a50731091deb462b42 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
//CLI Midi file player based on libfluidsynth
//Midi file reading module
//Written by Chris Xiong, 2015
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <cstdint>
#include <cstdarg>
#include <algorithm>
#include "qmpmidiplay.hpp"
const char* GM1SysX={"\xF0\x7E\x7F\x09\x01\xF7"};
const char* GM2SysX={"\xF0\x7E\x7F\x09\x03\xF7"};
const char* GSSysEx={"\xF0\x41\x10\x42\x12\x40\x00\x7F\x00\x41\xF7"};
const char* XGSysEx={"\xF0\x43\x10\x4C\x00\x00\x7E\x00\xF7"};
bool cmp(SEvent *a,SEvent *b){return a->time-b->time?a->time<b->time:a->iid<b->iid;}
void CMidiFile::error(int fatal,const char* format,...)
{
	va_list ap;
	va_start(ap,format);vfprintf(stderr,format,ap);va_end(ap);
	fprintf(stderr," at %#lx\n",ftell(f));
	if(fatal)throw 2;
}
uint32_t CMidiFile::readSW()
{
	byteread+=2;
	uint32_t ret=0;
	for(int i=0;i<2;++i){ret<<=8;ret|=((uint32_t)fgetc(f))&0xFF;}
	return ret;
}
uint32_t CMidiFile::readDW()
{
	byteread+=4;
	uint32_t ret=0;
	for(int i=0;i<4;++i){ret<<=8;ret|=((uint32_t)fgetc(f))&0xFF;}
	return ret;
}
uint32_t CMidiFile::readVL()
{
	uint32_t ret=0,t,c=0;
	do
	{
		t=fgetc(f);
		if(++c>4)error(1,"E: Variable length type overflow.");
		ret<<=7;ret|=(t&0x7F);
	}while(t&0x80);
	byteread+=c;
	return ret;
}
int CMidiFile::eventReader()//returns 0 if End of Track encountered
{
	uint32_t delta=readVL();curt+=delta;
	char type=fgetc(f);++byteread;uint32_t p1,p2;
	static char lasttype;
retry:
	switch(type&0xF0)
	{
		case 0x80://Note Off
			p1=fgetc(f);p2=fgetc(f);byteread+=2;
			eventList[eventc++]=new SEvent(curid,curt,type,p1,p2);
		break;
		case 0x90://Note On
			p1=fgetc(f);p2=fgetc(f);byteread+=2;
			if(p2)
			{
				++notes;
				eventList[eventc++]=new SEvent(curid,curt,type,p1,p2);
			}
			else
				eventList[eventc++]=new SEvent(curid,curt,(type&0x0F)|0x80,p1,p2);
		break;
		case 0xA0://Note Aftertouch
			p1=fgetc(f);p2=fgetc(f);byteread+=2;
			eventList[eventc++]=new SEvent(curid,curt,type,p1,p2);
		break;
		case 0xB0://Controller Change
			p1=fgetc(f);p2=fgetc(f);byteread+=2;
			eventList[eventc++]=new SEvent(curid,curt,type,p1,p2);
		break;
		case 0xC0://Patch Change
			p1=fgetc(f);++byteread;
			eventList[eventc++]=new SEvent(curid,curt,type,p1,0);
		break;
		case 0xD0://Channel Aftertouch
			p1=fgetc(f);++byteread;
			eventList[eventc++]=new SEvent(curid,curt,type,p1,0);
		break;
		case 0xE0://Pitch wheel
			p1=fgetc(f);p2=fgetc(f);byteread+=2;
			eventList[eventc++]=new SEvent(curid,curt,type,(p1|(p2<<7))&0x3FFF,0);
		break;
		case 0xF0:
			if((type&0x0F)==0x0F)//Meta Event
			{
				char metatype=fgetc(f);++byteread;
				switch(metatype)
				{
					case 0x00://Sequence Number
						fgetc(f);fgetc(f);fgetc(f);
						byteread+=3;
					break;
					case 0x20://Channel Prefix
						fgetc(f);fgetc(f);byteread+=2;
					break;
					case 0x2F://End of Track
						fgetc(f);++byteread;
						return 0;
					break;
					case 0x51://Set Tempo
						p1=readDW();p1&=0x00FFFFFF;
						eventList[eventc++]=new SEvent(curid,curt,type,metatype,p1);
					break;
					case 0x54://SMTPE offset, not handled.
						fgetc(f);fgetc(f);fgetc(f);
						fgetc(f);fgetc(f);fgetc(f);
						byteread+=6;
					break;
					case 0x58://Time signature
						fgetc(f);++byteread;
						p1=readDW();
						eventList[eventc++]=new SEvent(curid,curt,type,metatype,p1);
					break;
					case 0x59://Key signature
						fgetc(f);++byteread;
						p1=readSW();
						eventList[eventc++]=new SEvent(curid,curt,type,metatype,p1);
					break;
					case 0x01:case 0x02:case 0x03:
					case 0x04:case 0x05:case 0x06:
					case 0x07:case 0x7F:default://text-like meta
					{
						uint32_t len=readVL(),c;char* str=NULL;
						if(len<=1024&&len>0)str=new char[len+8];
						for(c=0;c<len;++c)
						{
							++byteread;if(str)str[c]=fgetc(f);else fgetc(f);
						}
						if(str)str[c]='\0';eventList[eventc++]=new SEvent(curid,curt,type,metatype,0,str);
						if(str&&metatype==0x03&&!title)
						{
							title=new char[len+8];
							strcpy(title,str);
						}
						if(str&&metatype==0x02&&!copyright)
						{
							copyright=new char[len+8];
							strcpy(copyright,str);
						}
						if(len<=1024&&len>0)delete[] str;
					}
				}
			}
			else if((type&0x0F)==0x00||(type&0x0F)==0x07)//SysEx
			{
				uint32_t len=readVL(),c;char* str=NULL;
				str=new char[len+8];
				if((type&0x0F)==0x00)
				{
					str[0]=0xF0;++len;
					for(c=1;c<len;++c){++byteread;str[c]=fgetc(f);}
				}
				else for(c=0;c<len;++c){++byteread;str[c]=fgetc(f);}
				eventList[eventc++]=new SEvent(curid,curt,type,len,0,str);
				if(!strcmp(str,GM1SysX))std=1;
				if(!strcmp(str,GM2SysX))std=2;
				if(!strcmp(str,GSSysEx))std=3;
				if(!strcmp(str,XGSysEx))std=4;
			}
			else error(0,"W: Unknown event type %#x",type);
		break;
		default:
			fseek(f,-1,SEEK_CUR);--byteread;type=lasttype;goto retry;
	}
	lasttype=type;++curid;
	return 1;
}
void CMidiFile::trackChunkReader()
{
	int chnklen=readDW();byteread=0;curt=0;curid=0;
	while(/*byteread<chnklen&&*/eventReader());
	if(byteread<chnklen)
	{
		error(0,"W: Extra bytes after EOT event.");
		while(byteread<chnklen){fgetc(f);++byteread;}
	}
	/*if(byteread>chnklen)
	{
		error(1,"E: Read past end of track.");
	}*/
}
void CMidiFile::headerChunkReader()
{
	int chnklen=readDW();byteread=0;
	if(chnklen<6)error(1,"E: Header chunk too short.");
	if(chnklen>6)error(0,"W: Header chunk length longer than expected. Ignoring extra bytes.");
	fmt=readSW();trk=readSW();divs=readSW();
	if(divs&0x8000)error(1,"E: SMTPE format is not supported.");
	for(;byteread<chnklen;++byteread){fgetc(f);}
}
int CMidiFile::chunkReader(int hdrXp)
{
	char hdr[6];
	if(!fgets(hdr,5,f))error(1,"E: Unexpected EOF.");
	if(hdrXp)
		if(strncmp(hdr,"MThd",4)){error(1,"E: Wrong MIDI header.");throw;}
		else return headerChunkReader(),0;
	else
		if(strncmp(hdr,"MTrk",4))
		{
			error(0,"W: Wrong track chunk header. Ignoring the whole chunk.");
			for(int chnklen=readDW();chnklen>0;--chnklen)fgetc(f);return 0;
		}
		else return trackChunkReader(),1;
}
CMidiFile::CMidiFile(const char* fn)
{
	title=copyright=NULL;notes=eventc=0;std=0;valid=1;
	try
	{
		if(!(f=fopen(fn,"rb")))throw (fprintf(stderr,"E: file %s doesn't exist!\n",fn),2);
		chunkReader(1);
		for(uint32_t i=0;i<trk;i+=chunkReader(0));
		printf("%d note(s)\n",notes);
		fclose(f);
		std::sort(eventList,eventList+eventc,cmp);
	}
	catch(int){fprintf(stderr,"E: %s is not a supported file.\n",fn);valid=0;}
}
CMidiFile::~CMidiFile()
{
	for(uint32_t i=0;i<eventc;++i)delete eventList[i];
	if(title)delete[] title;if(copyright)delete[] copyright;
}
const SEvent* CMidiFile::getEvent(uint32_t id){return id<eventc?eventList[id]:NULL;}
uint32_t CMidiFile::getEventCount(){return eventc;}
uint32_t CMidiFile::getDivision(){return divs;}
uint32_t CMidiFile::getNoteCount(){return notes;}
uint32_t CMidiFile::getStandard(){return std;}
bool CMidiFile::isValid(){return valid;}
const char* CMidiFile::getTitle(){return title;}
const char* CMidiFile::getCopyright(){return copyright;}