ardour/libs/evoral/libsmf/smf_save.c

685 lines
15 KiB
C

/*-
* Copyright (c) 2007, 2008 Edward Tomasz Napierała <trasz@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* ALTHOUGH THIS SOFTWARE IS MADE OF WIN AND SCIENCE, IT IS PROVIDED BY THE
* AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
* OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
/**
* \file
*
* Standard MIDI File writer.
*
*/
/* Reference: http://www.borg.com/~jglatt/tech/midifile.htm */
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <math.h>
#include <errno.h>
#include "pbd/assert.h"
#include "smf.h"
#include "smf_private.h"
#define MAX_VLQ_LENGTH 128
/**
* Extends (reallocates) smf->file_buffer and returns pointer to the newly added space,
* that is, pointer to the first byte after the previous buffer end. Returns NULL in case
* of error.
*/
static void *
smf_extend(smf_t *smf, const int length)
{
int i, previous_file_buffer_length = smf->file_buffer_length;
char *previous_file_buffer = (char*)smf->file_buffer;
/* XXX: Not terribly efficient. */
smf->file_buffer_length += length;
smf->file_buffer = realloc(smf->file_buffer, smf->file_buffer_length);
if (smf->file_buffer == NULL) {
g_warning("realloc(3) failed: %s", strerror(errno));
smf->file_buffer_length = 0;
return (NULL);
}
/* Fix up pointers. XXX: omgwtf. */
for (i = 1; i <= smf->number_of_tracks; i++) {
smf_track_t *track;
track = smf_get_track_by_number(smf, i);
if (track->file_buffer != NULL)
track->file_buffer = (char *)track->file_buffer + ((char *)smf->file_buffer - previous_file_buffer);
}
return ((char *)smf->file_buffer + previous_file_buffer_length);
}
/**
* Appends "buffer_length" bytes pointed to by "buffer" to the smf, reallocating storage as needed. Returns 0
* if everything went ok, different value if there was any problem.
*/
static int
smf_append(smf_t *smf, const void *buffer, const int buffer_length)
{
void *dest;
dest = smf_extend(smf, buffer_length);
if (dest == NULL) {
g_warning("Cannot extend track buffer.");
return (-1);
}
memcpy(dest, buffer, buffer_length);
return (0);
}
/**
* Appends MThd header to the track. Returns 0 if everything went ok, different value if not.
*/
static int
write_mthd_header(smf_t *smf)
{
struct mthd_chunk_struct mthd_chunk;
memcpy(mthd_chunk.mthd_header.id, "MThd", 4);
mthd_chunk.mthd_header.length = GUINT32_TO_BE(6);
mthd_chunk.format = GUINT16_TO_BE(smf->format);
mthd_chunk.number_of_tracks = GUINT16_TO_BE(smf->number_of_tracks);
mthd_chunk.division = GUINT16_TO_BE(smf->ppqn);
return (smf_append(smf, &mthd_chunk, sizeof(mthd_chunk)));
}
/**
* Extends (reallocates) track->file_buffer and returns pointer to the newly added space,
* that is, pointer to the first byte after the previous buffer end. Returns NULL in case
* of error.
*/
static void *
track_extend(smf_track_t *track, const int length)
{
void *buf;
assert(track->smf);
buf = smf_extend(track->smf, length);
if (buf == NULL)
return (NULL);
track->file_buffer_length += length;
if (track->file_buffer == NULL)
track->file_buffer = buf;
return (buf);
}
/**
* Appends "buffer_length" bytes pointed to by "buffer" to the track, reallocating storage as needed. Returns 0
* if everything went ok, different value if there was any problem.
*/
static int
track_append(smf_track_t *track, const void *buffer, const int buffer_length)
{
void *dest;
dest = track_extend(track, buffer_length);
if (dest == NULL) {
g_warning("Cannot extend track buffer.");
return (-1);
}
memcpy(dest, buffer, buffer_length);
return (0);
}
int
smf_format_vlq(unsigned char *buf, int length, unsigned long value)
{
int i;
unsigned long buffer;
/* Taken from http://www.borg.com/~jglatt/tech/midifile/vari.htm */
buffer = value & 0x7F;
while ((value >>= 7)) {
buffer <<= 8;
buffer |= ((value & 0x7F) | 0x80);
}
for (i = 0;; i++) {
buf[i] = buffer;
if (buffer & 0x80)
buffer >>= 8;
else
break;
}
assert(i <= length);
/* + 1, because "i" is an offset, not a count. */
return (i + 1);
}
smf_event_t *
smf_event_new_textual(int type, const char *text)
{
int vlq_length, text_length;
smf_event_t *event;
assert(type >= 1 && type <= 9);
text_length = strlen(text);
event = smf_event_new();
if (event == NULL)
return (NULL);
/* "2 +" is for leading 0xFF 0xtype. */
event->midi_buffer_length = 2 + text_length + MAX_VLQ_LENGTH;
event->midi_buffer = (uint8_t*)malloc(event->midi_buffer_length);
if (event->midi_buffer == NULL) {
g_warning("Cannot allocate MIDI buffer structure: %s", strerror(errno));
smf_event_delete(event);
return (NULL);
}
event->midi_buffer[0] = 0xFF;
event->midi_buffer[1] = type;
vlq_length = smf_format_vlq(event->midi_buffer + 2, MAX_VLQ_LENGTH - 2, text_length);
int copied_length;
copied_length = snprintf((char *)event->midi_buffer + vlq_length + 2, event->midi_buffer_length - vlq_length - 2, "%s", text);
x_assert (copied_length, copied_length == text_length);
event->midi_buffer_length = 2 + vlq_length + text_length;
return event;
}
/**
* Appends value, expressed as Variable Length Quantity, to event->track.
*/
static int
write_vlq(smf_event_t *event, unsigned long value)
{
unsigned char buf[MAX_VLQ_LENGTH];
int vlq_length;
vlq_length = smf_format_vlq(buf, MAX_VLQ_LENGTH, value);
return (track_append(event->track, buf, vlq_length));
}
/**
* Appends event time as Variable Length Quantity. Returns 0 if everything went ok,
* different value in case of error.
*/
static int
write_event_time(smf_event_t *event)
{
assert(event->delta_time_pulses >= 0);
return (write_vlq(event, event->delta_time_pulses));
}
static int
write_sysex_contents(smf_event_t *event)
{
int ret;
unsigned char sysex_status = 0xF0;
assert(smf_event_is_sysex(event));
ret = track_append(event->track, &sysex_status, 1);
if (ret)
return (ret);
/* -1, because length does not include status byte. */
ret = write_vlq(event, event->midi_buffer_length - 1);
if (ret)
return (ret);
ret = track_append(event->track, event->midi_buffer + 1, event->midi_buffer_length - 1);
if (ret)
return (ret);
return (0);
}
/**
* Appends contents of event->midi_buffer wrapped into 0xF7 MIDI event.
*/
static int
write_escaped_event_contents(smf_event_t *event)
{
int ret;
unsigned char escape_status = 0xF7;
if (smf_event_is_sysex(event))
return (write_sysex_contents(event));
ret = track_append(event->track, &escape_status, 1);
if (ret)
return (ret);
ret = write_vlq(event, event->midi_buffer_length);
if (ret)
return (ret);
ret = track_append(event->track, event->midi_buffer, event->midi_buffer_length);
if (ret)
return (ret);
return (0);
}
/**
* Appends contents of event->midi_buffer. Returns 0 if everything went 0,
* different value in case of error.
*/
static int
write_event_contents(smf_event_t *event)
{
if (smf_event_is_system_realtime(event) || smf_event_is_system_common(event))
return (write_escaped_event_contents(event));
return (track_append(event->track, event->midi_buffer, event->midi_buffer_length));
}
/**
* Writes out an event.
*/
static int
write_event(smf_event_t *event)
{
int ret;
ret = write_event_time(event);
if (ret)
return (ret);
ret = write_event_contents(event);
if (ret)
return (ret);
return (0);
}
/**
* Writes out MTrk header, except of MTrk chunk length, which is written by write_mtrk_length().
*/
static int
write_mtrk_header(smf_track_t *track)
{
struct chunk_header_struct mtrk_header;
memcpy(mtrk_header.id, "MTrk", 4);
return (track_append(track, &mtrk_header, sizeof(mtrk_header)));
}
/**
* Updates MTrk chunk length of a given track.
*/
static int
write_mtrk_length(smf_track_t *track)
{
struct chunk_header_struct *mtrk_header;
assert(track->file_buffer != NULL);
assert(track->file_buffer_length >= 6);
mtrk_header = (struct chunk_header_struct *)track->file_buffer;
mtrk_header->length = GUINT32_TO_BE(track->file_buffer_length - sizeof(struct chunk_header_struct));
return (0);
}
/**
* Writes out the track.
*/
static int
write_track(smf_track_t *track)
{
int ret;
smf_event_t *event;
ret = write_mtrk_header(track);
if (ret)
return (ret);
if (track->name) {
printf ("save track name [%s]\n", track->name);
smf_event_t *ev = smf_event_new_textual (0x03, track->name);
ev->delta_time_pulses = 0; /* time zero */
ev->track = track;
ret = write_event (ev);
ev->track = 0;
smf_event_delete (ev);
if (ret) {
return ret;
}
}
if (track->instrument) {
printf ("save track instrument [%s]\n", track->instrument);
smf_event_t *ev = smf_event_new_textual (0x04, track->instrument);
ev->delta_time_pulses = 0; /* time zero */
ev->track = track;
ret = write_event (ev);
ev->track = 0;
smf_event_delete (ev);
if (ret) {
return ret;
}
}
while ((event = smf_track_get_next_event(track)) != NULL) {
ret = write_event(event);
if (ret)
return (ret);
}
ret = write_mtrk_length(track);
if (ret)
return (ret);
return (0);
}
/**
* Takes smf->file_buffer and saves it to the file.
*/
static int
write_file(smf_t *smf, FILE* stream)
{
if (fwrite(smf->file_buffer, 1, smf->file_buffer_length, stream) != smf->file_buffer_length) {
g_warning("fwrite(3) failed: %s", strerror(errno));
return (-2);
}
return (0);
}
static void
free_buffer(smf_t *smf)
{
int i;
smf_track_t *track;
/* Clear the pointers. */
memset(smf->file_buffer, 0, smf->file_buffer_length);
free(smf->file_buffer);
smf->file_buffer = NULL;
smf->file_buffer_length = 0;
for (i = 1; i <= smf->number_of_tracks; i++) {
track = smf_get_track_by_number(smf, i);
assert(track);
track->file_buffer = NULL;
track->file_buffer_length = 0;
}
}
#ifndef NDEBUG
/**
* \return Nonzero, if all pointers supposed to be NULL are NULL. Triggers assertion if not.
*/
static int
pointers_are_clear(smf_t *smf)
{
int i;
smf_track_t *track;
if (smf->file_buffer != NULL) {
fprintf (stderr, "SFB != null but == %p\n", smf->file_buffer);
}
assert(smf->file_buffer == NULL);
assert(smf->file_buffer_length == 0);
for (i = 1; i <= smf->number_of_tracks; i++) {
track = smf_get_track_by_number(smf, i);
assert(track != NULL);
assert(track->file_buffer == NULL);
assert(track->file_buffer_length == 0);
}
return (1);
}
#endif /* !NDEBUG */
/**
* \return Nonzero, if event is End Of Track metaevent.
*/
int
smf_event_is_eot(const smf_event_t *event)
{
if (event->midi_buffer_length != 3)
return (0);
if (event->midi_buffer[0] != 0xFF || event->midi_buffer[1] != 0x2F || event->midi_buffer[2] != 0x00)
return (0);
return (1);
}
/**
* Check if SMF is valid and add missing EOT events.
*
* \return 0, if SMF is valid.
*/
static int
smf_validate(smf_t *smf)
{
int trackno, eot_found;
size_t eventno;
smf_track_t *track;
smf_event_t *event;
if (smf->format < 0 || smf->format > 2) {
g_warning("SMF error: smf->format is less than zero of greater than two.");
return (-1);
}
if (smf->number_of_tracks < 1) {
g_warning("SMF error: number of tracks is less than one.");
return (-2);
}
if (smf->format == 0 && smf->number_of_tracks > 1) {
g_warning("SMF error: format is 0, but number of tracks is more than one.");
return (-3);
}
if (smf->ppqn <= 0) {
g_warning("SMF error: PPQN has to be > 0.");
return (-4);
}
for (trackno = 1; trackno <= smf->number_of_tracks; trackno++) {
track = smf_get_track_by_number(smf, trackno);
assert(track);
eot_found = 0;
for (eventno = 1; eventno <= track->number_of_events; eventno++) {
event = smf_track_get_event_by_number(track, eventno);
assert(event);
if (!smf_event_is_valid(event)) {
g_warning("Event #%" G_GSIZE_FORMAT " on track #%d is invalid.", eventno, trackno);
return (-5);
}
if (smf_event_is_eot(event)) {
if (eot_found) {
g_warning("Duplicate End Of Track event on track #%d.", trackno);
return (-6);
}
eot_found = 1;
}
}
if (!eot_found) {
if (smf_track_add_eot_delta_pulses(track, 0)) {
g_warning("smf_track_add_eot_delta_pulses failed.");
return (-6);
}
}
}
return (0);
}
#ifndef NDEBUG
#define CHECK(cond) if (!(cond)) { return -1; }
static int
check_smf_event_is_identical(const smf_event_t *a, const smf_event_t *b)
{
CHECK(a->event_number == b->event_number);
CHECK(a->delta_time_pulses == b->delta_time_pulses);
CHECK(labs((long)(a->time_pulses - b->time_pulses)) <= 2);
CHECK(a->track_number == b->track_number);
CHECK(a->midi_buffer_length == b->midi_buffer_length);
CHECK(memcmp(a->midi_buffer, b->midi_buffer, a->midi_buffer_length) == 0);
return 0;
}
static int
check_smf_track_is_identical(const smf_track_t *a, const smf_track_t *b)
{
size_t i;
CHECK(a->track_number == b->track_number);
CHECK(a->number_of_events == b->number_of_events);
for (i = 1; i <= a->number_of_events; i++)
check_smf_event_is_identical(smf_track_get_event_by_number(a, i), smf_track_get_event_by_number(b, i));
return 0;
}
static int
check_smf_is_identical(const smf_t *a, const smf_t *b)
{
int i;
CHECK(a->format == b->format);
CHECK(a->ppqn == b->ppqn);
CHECK(a->frames_per_second == b->frames_per_second);
CHECK(a->resolution == b->resolution);
CHECK(a->number_of_tracks == b->number_of_tracks);
for (i = 1; i <= a->number_of_tracks; i++)
check_smf_track_is_identical(smf_get_track_by_number(a, i), smf_get_track_by_number(b, i));
/* We do not need to compare tempos explicitly, as tempo is always computed from track contents. */
return 0;
}
static int
check_smf_saved_correctly(const smf_t *smf, FILE* file)
{
smf_t *saved;
int ret;
saved = smf_load (file);
if (!saved) {
ret = -1;
} else {
ret = check_smf_is_identical(smf, saved);
}
smf_delete(saved);
return (ret);
}
#endif /* !NDEBUG */
/**
* Writes the contents of SMF to the file given.
* \param smf SMF.
* \param file File descriptor.
* \return 0, if saving was successfull.
*/
int
smf_save(smf_t *smf, FILE* file)
{
int i, error;
smf_track_t *track;
smf_rewind(smf);
assert(pointers_are_clear(smf));
if (smf_validate(smf))
return (-1);
if (write_mthd_header(smf))
return (-2);
for (i = 1; i <= smf->number_of_tracks; i++) {
track = smf_get_track_by_number(smf, i);
assert(track != NULL);
error = write_track(track);
if (error) {
free_buffer(smf);
return (error);
}
}
error = write_file(smf, file);
free_buffer(smf);
if (error)
return (error);
#ifndef NDEBUG
if (check_smf_saved_correctly(smf, file)) {
g_warning("SMF warning: Did not save correctly, possible data loss.");
}
#endif
return (0);
}