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#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#include <inttypes.h>
#include "platform.h"
#include "metadata.h"
#include "metadata_common.h"
#include "metadata_parsers.h"
#include "rbunicode.h"
#include "string-extra.h"
typedef unsigned char uchar;
typedef unsigned short ushort;
typedef unsigned int uint;
typedef unsigned long ulong;
typedef enum {
VTX_CHIP_AY = 0, /* emulate AY */
VTX_CHIP_YM /* emulate YM */
} vtx_chiptype_t;
typedef enum {
VTX_LAYOUT_MONO = 0,
VTX_LAYOUT_ABC,
VTX_LAYOUT_ACB,
VTX_LAYOUT_BAC,
VTX_LAYOUT_BCA,
VTX_LAYOUT_CAB,
VTX_LAYOUT_CBA,
VTX_LAYOUT_CUSTOM
} vtx_layout_t;
typedef struct {
vtx_chiptype_t chiptype; /* Type of sound chip */
vtx_layout_t layout; /* stereo layout */
uint loop; /* song loop */
uint chipfreq; /* AY chip freq (1773400 for ZX) */
uint playerfreq; /* 50 Hz for ZX, 60 Hz for yamaha */
uint year; /* year song composed */
char *title; /* song title */
char *author; /* song author */
char *from; /* song from */
char *tracker; /* tracker */
char *comment; /* comment */
uint regdata_size; /* size of unpacked data */
uint frames; /* number of AY data frames */
} vtx_info_t;
#define VTX_STRING_MAX 254
static uint Reader_ReadByte(int fd) {
unsigned char c = 0;
(void)read(fd, &c, sizeof(c));
return c;
}
static uint Reader_ReadWord(int fd) {
unsigned short s = 0;
(void)read(fd, &s, sizeof(s));
return letoh16(s);
}
static uint Reader_ReadDWord(int fd) {
unsigned int i = 0;
(void)read(fd, &i, sizeof(i));
return letoh32(i);
}
static char* Reader_ReadString(int fd, char *str) {
/*Note: still advances file buffer even if no string buffer supplied */
int i = 0;
char ch = '\0';
char *p = str;
while (i < VTX_STRING_MAX && (ch || i == 0))
{
if (read(fd, &ch, sizeof(ch) == sizeof(ch)))
{
if (str)
*str++ = ch;
}
else
break;
i++;
}
if (str)
*str = '\0';
return p;
}
/* vtx info */
bool get_vtx_metadata(int fd, struct mp3entry* id3)
{
vtx_info_t info;
char *p = id3->id3v2buf;
char buf[VTX_STRING_MAX+1];
if (lseek(fd, 0, SEEK_SET) < 0)
goto exit_bad;
if (filesize(fd) < 20)
goto exit_bad;
uint hdr = Reader_ReadWord(fd);
if ((hdr != 0x7961) && (hdr != 0x6d79))
goto exit_bad;
info.layout = (vtx_layout_t)Reader_ReadByte(fd);
info.loop = Reader_ReadWord(fd);
info.chipfreq = Reader_ReadDWord(fd);
info.playerfreq = Reader_ReadByte(fd);
info.year = Reader_ReadWord(fd);
info.regdata_size = Reader_ReadDWord(fd);
info.frames = info.regdata_size / 14;
info.title = Reader_ReadString(fd, buf);
if (buf[0]) {
/* Title */
id3->title = p;
p += strlcpy(p, info.title, VTX_STRING_MAX) + 1;
}
info.author = Reader_ReadString(fd, buf);
if (buf[0]) {
/* Artist */
id3->artist = p;
p += strlcpy(p, info.author, VTX_STRING_MAX) + 1;
}
info.from = Reader_ReadString(fd, NULL);
info.tracker = Reader_ReadString(fd, NULL);
info.comment = Reader_ReadString(fd, buf);
if (buf[0]) {
/* Comment */
id3->comment = p;
p += strlcpy(p, info.comment, VTX_STRING_MAX) + 1;
}
id3->vbr = false;
id3->bitrate = 706;
id3->frequency = 44100; // XXX allow this to be configured?
id3->filesize = filesize(fd);
id3->length = info.frames * 1000 / info.playerfreq;
return true;
exit_bad:
return false;
}
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