/*========== Loader code */
bool LoadModuleHeader(M15ModuleHeader mh)
{
int t, u;
mh.songname = m_Reader.Read_String(20);
/* sanity check : title should contain printable characters and a bunch
* of null chars */
for (t = 0; t < mh.songname.Length; t++)
{
if ((mh.songname[t] != 0) && (mh.songname[t] < 32))
{
return(false);
}
}
for (t = 0; (t < mh.songname.Length) && (mh.songname[t] != 0); t++)
{
;
}
if (t < 20)
{
for (; t < mh.songname.Length; t++)
{
if (mh.songname[t] != 0)
{
return(false);
}
}
}
for (t = 0; t < 15; t++)
{
M15SampleInfo s = mh.samples[t];
s.samplename = m_Reader.Read_String(22);
s.length = m_Reader.Read_Motorola_ushort();
s.finetune = m_Reader.Read_byte();
s.volume = m_Reader.Read_byte();
s.reppos = m_Reader.Read_Motorola_ushort();
s.replen = m_Reader.Read_Motorola_ushort();
/* sanity check : sample title should contain printable characters and
* a bunch of null chars */
for (u = 0; u < s.samplename.Length; u++)
{
if ((s.samplename[u] != 0) && (s.samplename[u] < /*32*/ 14))
{
return(false);
}
}
for (u = 0; (u < s.samplename.Length) && (s.samplename[u] != 0); u++)
{
;
}
if (u < 20)
{
for (; u < s.samplename.Length; u++)
{
if (s.samplename[u] != 0)
{
return(false);
}
}
}
/* sanity check : finetune values */
if ((s.finetune >> 4) != 0)
{
return(false);
}
}
mh.songlength = m_Reader.Read_byte();
mh.magic1 = m_Reader.Read_byte(); /* should be 127 */
/* sanity check : no more than 128 positions, restart position in range */
if ((mh.songlength == 0) || (mh.songlength > 128))
{
return(false);
}
/* values encountered so far are 0x6a and 0x78 */
if (((mh.magic1 & 0xf8) != 0x78) && (mh.magic1 != 0x6a) && (mh.magic1 > mh.songlength))
{
return(false);
}
m_Reader.Read_bytes(mh.positions, 128);
/* sanity check : pattern range is 0..63 */
for (t = 0; t < 128; t++)
{
if (mh.positions[t] > 63)
{
return(false);
}
}
return(!m_Reader.isEOF());
}
public override bool Test()
{
int t, numpat;
mh = new M15ModuleHeader();
ust_loader = false;
if (!LoadModuleHeader(mh))
{
return(false);
}
/* reject other file types */
for (t = 0; t < REJECT; t++)
{
if (mh.songname == signatures[t])
{
mh = null;
return(false);
}
}
if (mh.magic1 > 127)
{
return(false);
}
if ((mh.songlength == 0) || (mh.songlength > mh.magic1))
{
return(false);
}
for (t = 0; t < 15; t++)
{
/* all finetunes should be zero */
if (mh.samples[t].finetune != 0)
{
return(false);
}
/* all volumes should be <= 64 */
if (mh.samples[t].volume > 64)
{
return(false);
}
/* all instrument names should begin with s, st-, or a number */
if (mh.samples[t].samplename.Length > 0 && (mh.samples[t].samplename[0] == 's' || mh.samples[t].samplename[0] == 'S'))
{
if (!String.IsNullOrEmpty(mh.samples[t].samplename) && !mh.samples[t].samplename.StartsWith("st-") && !mh.samples[t].samplename.StartsWith("ST-"))
{
ust_loader = true;
}
}
else
{
if (mh.samples[t].samplename.Length == 0 || (mh.samples[t].samplename.Length > 0 && !char.IsDigit(mh.samples[t].samplename[0])))
{
ust_loader = true;
}
}
if (mh.samples[t].length > 4999 || mh.samples[t].reppos > 9999)
{
ust_loader = false;
if (mh.samples[t].length > 32768)
{
return(false);
}
}
/* 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 = true;
return(true);
}
if (!ust_loader)
{
return(true);
}
}
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 = true;
break;
case 2:
ust_loader = false;
break;
}
return(true);
}
public override void Cleanup()
{
patbuf = null;
mh = null;
}
public override bool Init()
{
mh = new M15ModuleHeader();
return(true);
}
