2 * Copyright (c) 2007, 2008 Edward Tomasz NapieraĆa <trasz@FreeBSD.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * ALTHOUGH THIS SOFTWARE IS MADE OF WIN AND SCIENCE, IT IS PROVIDED BY THE
15 * AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
16 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
17 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
18 * THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
19 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
20 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
21 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
22 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
23 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
24 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 * Standard MIDI File writer.
35 /* Reference: http://www.borg.com/~jglatt/tech/midifile.htm */
42 #include <arpa/inet.h>
44 #include "smf_private.h"
46 #define MAX_VLQ_LENGTH 128
49 * Extends (reallocates) smf->file_buffer and returns pointer to the newly added space,
50 * that is, pointer to the first byte after the previous buffer end. Returns NULL in case
54 smf_extend(smf_t *smf, const int length)
56 int i, previous_file_buffer_length = smf->file_buffer_length;
57 char *previous_file_buffer = smf->file_buffer;
59 /* XXX: Not terribly efficient. */
60 smf->file_buffer_length += length;
61 smf->file_buffer = realloc(smf->file_buffer, smf->file_buffer_length);
62 if (smf->file_buffer == NULL) {
63 g_critical("realloc(3) failed: %s", strerror(errno));
64 smf->file_buffer_length = 0;
68 /* Fix up pointers. XXX: omgwtf. */
69 for (i = 1; i <= smf->number_of_tracks; i++) {
71 track = smf_get_track_by_number(smf, i);
72 if (track->file_buffer != NULL)
73 track->file_buffer = (char *)track->file_buffer + ((char *)smf->file_buffer - previous_file_buffer);
76 return ((char *)smf->file_buffer + previous_file_buffer_length);
80 * Appends "buffer_length" bytes pointed to by "buffer" to the smf, reallocating storage as needed. Returns 0
81 * if everything went ok, different value if there was any problem.
84 smf_append(smf_t *smf, const void *buffer, const int buffer_length)
88 dest = smf_extend(smf, buffer_length);
90 g_critical("Cannot extend track buffer.");
94 memcpy(dest, buffer, buffer_length);
100 * Appends MThd header to the track. Returns 0 if everything went ok, different value if not.
103 write_mthd_header(smf_t *smf)
105 struct mthd_chunk_struct mthd_chunk;
107 memcpy(mthd_chunk.mthd_header.id, "MThd", 4);
108 mthd_chunk.mthd_header.length = htonl(6);
109 mthd_chunk.format = htons(smf->format);
110 mthd_chunk.number_of_tracks = htons(smf->number_of_tracks);
111 mthd_chunk.division = htons(smf->ppqn);
113 return (smf_append(smf, &mthd_chunk, sizeof(mthd_chunk)));
117 * Extends (reallocates) track->file_buffer and returns pointer to the newly added space,
118 * that is, pointer to the first byte after the previous buffer end. Returns NULL in case
122 track_extend(smf_track_t *track, const int length)
128 buf = smf_extend(track->smf, length);
132 track->file_buffer_length += length;
133 if (track->file_buffer == NULL)
134 track->file_buffer = buf;
140 * Appends "buffer_length" bytes pointed to by "buffer" to the track, reallocating storage as needed. Returns 0
141 * if everything went ok, different value if there was any problem.
144 track_append(smf_track_t *track, const void *buffer, const int buffer_length)
148 dest = track_extend(track, buffer_length);
150 g_critical("Cannot extend track buffer.");
154 memcpy(dest, buffer, buffer_length);
160 format_vlq(unsigned char *buf, int length, unsigned long value)
163 unsigned long buffer;
165 /* Taken from http://www.borg.com/~jglatt/tech/midifile/vari.htm */
166 buffer = value & 0x7F;
168 while ((value >>= 7)) {
170 buffer |= ((value & 0x7F) | 0x80);
184 /* + 1, because "i" is an offset, not a count. */
189 smf_event_new_textual(int type, const char *text)
191 int vlq_length, text_length, copied_length;
194 assert(type >= 1 && type <= 9);
196 text_length = strlen(text);
198 event = smf_event_new();
202 /* "2 +" is for leading 0xFF 0xtype. */
203 event->midi_buffer_length = 2 + text_length + MAX_VLQ_LENGTH;
204 event->midi_buffer = malloc(event->midi_buffer_length);
205 if (event->midi_buffer == NULL) {
206 g_critical("Cannot allocate MIDI buffer structure: %s", strerror(errno));
207 smf_event_delete(event);
212 event->midi_buffer[0] = 0xFF;
213 event->midi_buffer[1] = type;
215 vlq_length = format_vlq(event->midi_buffer + 2, MAX_VLQ_LENGTH - 2, text_length);
216 copied_length = snprintf((char *)event->midi_buffer + vlq_length + 2, event->midi_buffer_length - vlq_length - 2, "%s", text);
218 assert(copied_length == text_length);
220 event->midi_buffer_length = 2 + vlq_length + text_length;
226 * Appends value, expressed as Variable Length Quantity, to event->track.
229 write_vlq(smf_event_t *event, unsigned long value)
231 unsigned char buf[MAX_VLQ_LENGTH];
234 vlq_length = format_vlq(buf, MAX_VLQ_LENGTH, value);
236 return (track_append(event->track, buf, vlq_length));
240 * Appends event time as Variable Length Quantity. Returns 0 if everything went ok,
241 * different value in case of error.
244 write_event_time(smf_event_t *event)
246 assert(event->delta_time_pulses >= 0);
248 return (write_vlq(event, event->delta_time_pulses));
252 write_sysex_contents(smf_event_t *event)
255 unsigned char sysex_status = 0xF0;
257 assert(smf_event_is_sysex(event));
259 ret = track_append(event->track, &sysex_status, 1);
263 /* -1, because length does not include status byte. */
264 ret = write_vlq(event, event->midi_buffer_length - 1);
268 ret = track_append(event->track, event->midi_buffer + 1, event->midi_buffer_length - 1);
276 * Appends contents of event->midi_buffer wrapped into 0xF7 MIDI event.
279 write_escaped_event_contents(smf_event_t *event)
282 unsigned char escape_status = 0xF7;
284 if (smf_event_is_sysex(event))
285 return (write_sysex_contents(event));
287 ret = track_append(event->track, &escape_status, 1);
291 ret = write_vlq(event, event->midi_buffer_length);
295 ret = track_append(event->track, event->midi_buffer, event->midi_buffer_length);
303 * Appends contents of event->midi_buffer. Returns 0 if everything went 0,
304 * different value in case of error.
307 write_event_contents(smf_event_t *event)
309 if (smf_event_is_system_realtime(event) || smf_event_is_system_common(event))
310 return (write_escaped_event_contents(event));
312 return (track_append(event->track, event->midi_buffer, event->midi_buffer_length));
316 * Writes out an event.
319 write_event(smf_event_t *event)
323 ret = write_event_time(event);
327 ret = write_event_contents(event);
335 * Writes out MTrk header, except of MTrk chunk length, which is written by write_mtrk_length().
338 write_mtrk_header(smf_track_t *track)
340 struct chunk_header_struct mtrk_header;
342 memcpy(mtrk_header.id, "MTrk", 4);
344 return (track_append(track, &mtrk_header, sizeof(mtrk_header)));
348 * Updates MTrk chunk length of a given track.
351 write_mtrk_length(smf_track_t *track)
353 struct chunk_header_struct *mtrk_header;
355 assert(track->file_buffer != NULL);
356 assert(track->file_buffer_length >= 6);
358 mtrk_header = (struct chunk_header_struct *)track->file_buffer;
359 mtrk_header->length = htonl(track->file_buffer_length - sizeof(struct chunk_header_struct));
365 * Writes out the track.
368 write_track(smf_track_t *track)
373 ret = write_mtrk_header(track);
377 while ((event = smf_track_get_next_event(track)) != NULL) {
378 ret = write_event(event);
383 ret = write_mtrk_length(track);
391 * Takes smf->file_buffer and saves it to the file.
394 write_file(smf_t *smf, const char *file_name)
398 stream = fopen(file_name, "w+");
399 if (stream == NULL) {
400 g_critical("Cannot open input file: %s", strerror(errno));
405 if (fwrite(smf->file_buffer, 1, smf->file_buffer_length, stream) != smf->file_buffer_length) {
406 g_critical("fwrite(3) failed: %s", strerror(errno));
411 if (fclose(stream)) {
412 g_critical("fclose(3) failed: %s", strerror(errno));
421 free_buffer(smf_t *smf)
426 /* Clear the pointers. */
427 memset(smf->file_buffer, 0, smf->file_buffer_length);
428 free(smf->file_buffer);
429 smf->file_buffer = NULL;
430 smf->file_buffer_length = 0;
432 for (i = 1; i <= smf->number_of_tracks; i++) {
433 track = smf_get_track_by_number(smf, i);
435 track->file_buffer = NULL;
436 track->file_buffer_length = 0;
443 * \return Nonzero, if all pointers supposed to be NULL are NULL. Triggers assertion if not.
446 pointers_are_clear(smf_t *smf)
451 assert(smf->file_buffer == NULL);
452 assert(smf->file_buffer_length == 0);
454 for (i = 1; i <= smf->number_of_tracks; i++) {
455 track = smf_get_track_by_number(smf, i);
457 assert(track != NULL);
458 assert(track->file_buffer == NULL);
459 assert(track->file_buffer_length == 0);
468 * \return Nonzero, if event is End Of Track metaevent.
471 smf_event_is_eot(const smf_event_t *event)
473 if (event->midi_buffer_length != 3)
476 if (event->midi_buffer[0] != 0xFF || event->midi_buffer[1] != 0x2F || event->midi_buffer[2] != 0x00)
483 * Check if SMF is valid and add missing EOT events.
485 * \return 0, if SMF is valid.
488 smf_validate(smf_t *smf)
490 int trackno, eventno, eot_found;
494 if (smf->format < 0 || smf->format > 2) {
495 g_critical("SMF error: smf->format is less than zero of greater than two.");
499 if (smf->number_of_tracks < 1) {
500 g_critical("SMF error: number of tracks is less than one.");
504 if (smf->format == 0 && smf->number_of_tracks > 1) {
505 g_critical("SMF error: format is 0, but number of tracks is more than one.");
509 if (smf->ppqn <= 0) {
510 g_critical("SMF error: PPQN has to be > 0.");
514 for (trackno = 1; trackno <= smf->number_of_tracks; trackno++) {
515 track = smf_get_track_by_number(smf, trackno);
520 for (eventno = 1; eventno <= track->number_of_events; eventno++) {
521 event = smf_track_get_event_by_number(track, eventno);
524 if (!smf_event_is_valid(event)) {
525 g_critical("Event #%d on track #%d is invalid.", eventno, trackno);
529 if (smf_event_is_eot(event)) {
531 g_critical("Duplicate End Of Track event on track #%d.", trackno);
540 if (smf_track_add_eot_delta_pulses(track, 0)) {
541 g_critical("smf_track_add_eot_delta_pulses failed.");
554 assert_smf_event_is_identical(const smf_event_t *a, const smf_event_t *b)
556 assert(a->event_number == b->event_number);
557 assert(a->delta_time_pulses == b->delta_time_pulses);
558 assert(abs(a->time_pulses - b->time_pulses) <= 2);
559 assert(fabs(a->time_seconds - b->time_seconds) <= 0.01);
560 assert(a->track_number == b->track_number);
561 assert(a->midi_buffer_length == b->midi_buffer_length);
562 assert(memcmp(a->midi_buffer, b->midi_buffer, a->midi_buffer_length) == 0);
566 assert_smf_track_is_identical(const smf_track_t *a, const smf_track_t *b)
570 assert(a->track_number == b->track_number);
571 assert(a->number_of_events == b->number_of_events);
573 for (i = 1; i <= a->number_of_events; i++)
574 assert_smf_event_is_identical(smf_track_get_event_by_number(a, i), smf_track_get_event_by_number(b, i));
578 assert_smf_is_identical(const smf_t *a, const smf_t *b)
582 assert(a->format == b->format);
583 assert(a->ppqn == b->ppqn);
584 assert(a->frames_per_second == b->frames_per_second);
585 assert(a->resolution == b->resolution);
586 assert(a->number_of_tracks == b->number_of_tracks);
588 for (i = 1; i <= a->number_of_tracks; i++)
589 assert_smf_track_is_identical(smf_get_track_by_number(a, i), smf_get_track_by_number(b, i));
591 /* We do not need to compare tempos explicitly, as tempo is always computed from track contents. */
595 assert_smf_saved_correctly(const smf_t *smf, const char *file_name)
599 saved = smf_load(file_name);
600 assert(saved != NULL);
602 assert_smf_is_identical(smf, saved);
610 * Writes the contents of SMF to the file given.
612 * \param file_name Path to the file.
613 * \return 0, if saving was successfull.
616 smf_save(smf_t *smf, const char *file_name)
623 assert(pointers_are_clear(smf));
625 if (smf_validate(smf))
628 if (write_mthd_header(smf))
631 for (i = 1; i <= smf->number_of_tracks; i++) {
632 track = smf_get_track_by_number(smf, i);
634 assert(track != NULL);
636 error = write_track(track);
643 error = write_file(smf, file_name);
651 assert_smf_saved_correctly(smf, file_name);