ref: cab1803f1d6517754696b5c3d9b600e23ef9015e
dir: /src/it/readmtm.c/
/* _______ ____ __ ___ ___
* \ _ \ \ / \ / \ \ / / ' ' '
* | | \ \ | | || | \/ | . .
* | | | | | | || ||\ /| |
* | | | | | | || || \/ | | ' ' '
* | | | | | | || || | | . .
* | |_/ / \ \__// || | |
* /_______/ynamic \____/niversal /__\ /____\usic /| . . ibliotheque
* / \
* / . \
* readmtm.c - Code to read a MultiTracker Module / / \ \
* from an open file. | < / \_
* | \/ /\ /
* By Christopher Snowhill. \_ / > /
* | \ / /
* | ' /
* \__/
*/
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include "dumb.h"
#include "internal/it.h"
size_t strlen_max(const char *ptr, size_t max) {
const char *end, *start;
if (ptr == 0)
return 0;
start = ptr;
end = ptr + max;
while (ptr < end && *ptr)
ptr++;
return ptr - start;
}
static int it_mtm_assemble_pattern(IT_PATTERN *pattern,
const unsigned char *track,
const unsigned short *sequence, int n_rows) {
int n, o, note, sample;
const unsigned char *t;
IT_ENTRY *entry;
pattern->n_rows = n_rows;
pattern->n_entries = n_rows;
for (n = 0; n < 32; n++) {
if (sequence[n]) {
t = &track[192 * (sequence[n] - 1)];
for (o = 0; o < n_rows; o++) {
if (t[0] || t[1] || t[2])
pattern->n_entries++;
t += 3;
}
}
}
entry = malloc(pattern->n_entries * sizeof(*entry));
if (!entry)
return -1;
pattern->entry = entry;
for (n = 0; n < n_rows; n++) {
for (o = 0; o < 32; o++) {
if (sequence[o]) {
t = &track[192 * (sequence[o] - 1) + (n * 3)];
if (t[0] || t[1] || t[2]) {
entry->channel = o;
entry->mask = 0;
note = t[0] >> 2;
sample = ((t[0] << 4) | (t[1] >> 4)) & 0x3F;
if (note) {
entry->mask |= IT_ENTRY_NOTE;
entry->note = note + 24;
}
if (sample) {
entry->mask |= IT_ENTRY_INSTRUMENT;
entry->instrument = sample;
}
_dumb_it_xm_convert_effect(t[1] & 0xF, t[2], entry, 1);
if (entry->mask)
entry++;
}
}
}
IT_SET_END_ROW(entry);
entry++;
}
pattern->n_entries = (int)(entry - pattern->entry);
return 0;
}
static int it_mtm_read_sample_header(IT_SAMPLE *sample, DUMBFILE *f,
int *skip_bytes) {
int finetune, flags;
dumbfile_getnc((char *)sample->name, 22, f);
sample->name[22] = 0;
sample->filename[0] = 0;
sample->length = dumbfile_igetl(f);
sample->loop_start = dumbfile_igetl(f);
sample->loop_end = dumbfile_igetl(f);
finetune = (signed char)(dumbfile_getc(f) << 4) >> 4; /* signed nibble */
sample->global_volume = 64;
sample->default_volume = dumbfile_getc(f);
flags = dumbfile_getc(f);
if (sample->length <= 0) {
sample->flags = 0;
return 0;
}
sample->flags = IT_SAMPLE_EXISTS;
*skip_bytes = 0;
if (flags & 1) {
*skip_bytes = sample->length & 1;
sample->flags |= IT_SAMPLE_16BIT;
sample->length >>= 1;
sample->loop_start >>= 1;
sample->loop_end >>= 1;
}
sample->default_pan = 0;
sample->C5_speed =
(int)(AMIGA_CLOCK /
214.0); //(long)(16726.0*pow(DUMB_PITCH_BASE, finetune*32));
sample->finetune = finetune * 32;
// the above line might be wrong
if (sample->loop_end > sample->length)
sample->loop_end = sample->length;
if (sample->loop_end - sample->loop_start > 2)
sample->flags |= IT_SAMPLE_LOOP;
sample->vibrato_speed = 0;
sample->vibrato_depth = 0;
sample->vibrato_rate = 0;
sample->vibrato_waveform = 0; // do we have to set _all_ these?
sample->max_resampling_quality = -1;
return dumbfile_error(f);
}
static int it_mtm_read_sample_data(IT_SAMPLE *sample, DUMBFILE *f,
int skip_bytes) {
long i;
long truncated_size;
long bytes_per_sample;
/* let's get rid of the sample data coming after the end of the loop */
if ((sample->flags & IT_SAMPLE_LOOP) && sample->loop_end < sample->length) {
truncated_size = sample->length - sample->loop_end;
sample->length = sample->loop_end;
} else {
truncated_size = 0;
}
bytes_per_sample = (sample->flags & IT_SAMPLE_16BIT) ? 2 : 1;
sample->data = malloc(sample->length * bytes_per_sample);
if (!sample->data)
return -1;
dumbfile_getnc((char *)sample->data, sample->length * bytes_per_sample, f);
dumbfile_skip(f, truncated_size * bytes_per_sample);
dumbfile_skip(f, skip_bytes);
if (dumbfile_error(f))
return -1;
if (bytes_per_sample == 1)
for (i = 0; i < sample->length; i++)
((signed char *)sample->data)[i] ^= 0x80;
return 0;
}
static DUMB_IT_SIGDATA *it_mtm_load_sigdata(DUMBFILE *f, int *version) {
DUMB_IT_SIGDATA *sigdata;
int n, o, n_tracks, l_comment, n_rows, n_channels;
unsigned char *track;
unsigned short *sequence;
char *comment;
int *skip_bytes;
if (dumbfile_getc(f) != 'M' || dumbfile_getc(f) != 'T' ||
dumbfile_getc(f) != 'M')
goto error;
*version = dumbfile_getc(f);
sigdata = malloc(sizeof(*sigdata));
if (!sigdata)
goto error;
dumbfile_getnc((char *)sigdata->name, 20, f);
sigdata->name[20] = 0;
n_tracks = dumbfile_igetw(f);
sigdata->n_patterns = dumbfile_getc(f) + 1;
sigdata->n_orders = dumbfile_getc(f) + 1;
l_comment = dumbfile_igetw(f);
sigdata->n_samples = dumbfile_getc(f);
// if (dumbfile_getc(f)) goto error_sd;
dumbfile_getc(f);
n_rows = dumbfile_getc(f);
n_channels = dumbfile_getc(f);
if (dumbfile_error(f) || (n_tracks <= 0) || (sigdata->n_samples <= 0) ||
(n_rows <= 0 || n_rows > 64) || (n_channels <= 0 || n_channels > 32))
goto error_sd;
memset(sigdata->channel_volume, 64, DUMB_IT_N_CHANNELS);
if (dumbfile_getnc((char *)sigdata->channel_pan, 32, f) < 32)
goto error_sd;
for (n = 0; n < 32; n++) {
if (sigdata->channel_pan[n] <= 15) {
sigdata->channel_pan[n] -= (sigdata->channel_pan[n] & 8) >> 3;
sigdata->channel_pan[n] = (sigdata->channel_pan[n] * 32) / 7;
} else {
sigdata->channel_volume[n] = 0;
sigdata->channel_pan[n] = 7;
}
}
for (n = 32; n < DUMB_IT_N_CHANNELS; n += 4) {
int sep = 32 * dumb_it_default_panning_separation / 100;
sigdata->channel_pan[n] = 32 - sep;
sigdata->channel_pan[n + 1] = 32 + sep;
sigdata->channel_pan[n + 2] = 32 + sep;
sigdata->channel_pan[n + 3] = 32 - sep;
}
sigdata->sample = malloc(sigdata->n_samples * sizeof(*sigdata->sample));
if (!sigdata->sample)
goto error_sd;
sigdata->flags = IT_WAS_AN_XM | IT_WAS_A_MOD | IT_STEREO | IT_OLD_EFFECTS |
IT_COMPATIBLE_GXX;
sigdata->global_volume = 128;
sigdata->mixing_volume = 48;
sigdata->speed = 6;
sigdata->tempo = 125;
sigdata->pan_separation = 128;
sigdata->song_message = NULL;
sigdata->order = NULL;
sigdata->instrument = NULL;
sigdata->pattern = NULL;
sigdata->midi = NULL;
sigdata->checkpoint = NULL;
sigdata->n_instruments = 0;
sigdata->restart_position = 0;
sigdata->n_pchannels = n_channels;
for (n = 0; n < sigdata->n_samples; n++)
sigdata->sample[n].data = NULL;
skip_bytes = calloc(sizeof(int), sigdata->n_samples);
if (!skip_bytes)
goto error_usd;
for (n = 0; n < sigdata->n_samples; n++) {
if (it_mtm_read_sample_header(&sigdata->sample[n], f, skip_bytes + n))
goto error_sb;
}
sigdata->order = malloc(sigdata->n_orders);
if (!sigdata->order)
goto error_sb;
if (dumbfile_getnc((char *)sigdata->order, sigdata->n_orders, f) <
sigdata->n_orders)
goto error_sb;
if (sigdata->n_orders < 128)
if (dumbfile_skip(f, 128 - sigdata->n_orders))
goto error_sb;
track = malloc(192 * n_tracks);
if (!track)
goto error_sb;
if (dumbfile_getnc((char *)track, 192 * n_tracks, f) < 192 * n_tracks)
goto error_ft;
sigdata->pattern = malloc(sigdata->n_patterns * sizeof(*sigdata->pattern));
if (!sigdata->pattern)
goto error_ft;
for (n = 0; n < sigdata->n_patterns; n++)
sigdata->pattern[n].entry = NULL;
sequence = malloc(sigdata->n_patterns * 32 * sizeof(*sequence));
if (!sequence)
goto error_ft;
for (n = 0; n < sigdata->n_patterns; n++) {
for (o = 0; o < 32; o++) {
sequence[(n * 32) + o] = dumbfile_igetw(f);
if (sequence[(n * 32) + o] > n_tracks) {
// goto error_fs;
// illegal track number, silence instead of rejecting the file
sequence[(n * 32) + o] = 0;
}
}
}
for (n = 0; n < sigdata->n_patterns; n++) {
if (it_mtm_assemble_pattern(&sigdata->pattern[n], track,
&sequence[n * 32], n_rows))
goto error_fs;
}
if (l_comment) {
comment = malloc(l_comment);
if (!comment)
goto error_fs;
if (dumbfile_getnc(comment, l_comment, f) < l_comment)
goto error_fc;
/* Time for annoying "logic", yes. We want each line which has text,
* and each blank line in between all the valid lines.
*/
/* Find last actual line. */
for (o = -1, n = 0; n < l_comment; n += 40) {
if (comment[n])
o = n;
}
if (o >= 0) {
int l, m;
for (l = 0, n = 0; n <= o; n += 40) {
int maxlen = l_comment - n;
l += strlen_max(&comment[n], maxlen > 40 ? 40 : maxlen) + 2;
}
l -= 1;
sigdata->song_message = malloc(l);
if (!sigdata->song_message)
goto error_fc;
for (m = 0, n = 0; n <= o; n += 40) {
int maxlen = l_comment - n;
int p = (int)strlen_max(&comment[n], maxlen > 40 ? 40 : maxlen);
if (p) {
memcpy(sigdata->song_message + m, &comment[n], p);
m += p;
}
if (l - m > 1) {
sigdata->song_message[m++] = 13;
sigdata->song_message[m++] = 10;
}
}
sigdata->song_message[m] = 0;
}
free(comment);
}
for (n = 0; n < sigdata->n_samples; n++) {
if (it_mtm_read_sample_data(&sigdata->sample[n], f, skip_bytes[n]))
goto error_fs;
}
free(sequence);
free(track);
free(skip_bytes);
if (_dumb_it_fix_invalid_orders(sigdata) < 0) {
_dumb_it_unload_sigdata(sigdata);
return NULL;
}
return sigdata;
error_fc:
free(comment);
error_fs:
free(sequence);
error_ft:
free(track);
error_sb:
free(skip_bytes);
error_usd:
_dumb_it_unload_sigdata(sigdata);
return NULL;
error_sd:
free(sigdata);
error:
return NULL;
}
static char hexdigit(int in) {
if (in < 10)
return in + '0';
else
return in + 'A' - 10;
}
DUH *dumb_read_mtm_quick(DUMBFILE *f) {
sigdata_t *sigdata;
int ver;
DUH_SIGTYPE_DESC *descptr = &_dumb_sigtype_it;
sigdata = it_mtm_load_sigdata(f, &ver);
if (!sigdata)
return NULL;
{
char version[16];
const char *tag[2][2];
tag[0][0] = "TITLE";
tag[0][1] = (const char *)(((DUMB_IT_SIGDATA *)sigdata)->name);
tag[1][0] = "FORMAT";
version[0] = 'M';
version[1] = 'T';
version[2] = 'M';
version[3] = ' ';
version[4] = 'v';
version[5] = hexdigit(ver >> 4);
version[6] = '.';
version[7] = hexdigit(ver & 15);
version[8] = 0;
tag[1][1] = (const char *)&version;
return make_duh(-1, 2, (const char *const(*)[2])tag, 1, &descptr,
&sigdata);
}
}