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Commit 798f81df authored by Rémi Denis-Courmont's avatar Rémi Denis-Courmont Committed by Jean-Baptiste Kempf
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smf: reorder code, no functional changes

parent 3870474b
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Showing with 208 additions and 225 deletions
modules/demux/smf.c
View file @ 798f81df
......@@ -34,228 +34,6 @@
#define TEMPO_MIN 20
#define TEMPO_MAX 250 /* Beats per minute */
static int Open (vlc_object_t *);
static void Close (vlc_object_t *);
vlc_module_begin ()
set_description (N_("SMF demuxer"))
set_category (CAT_INPUT)
set_subcategory (SUBCAT_INPUT_DEMUX)
set_capability ("demux", 20)
set_callbacks (Open, Close)
vlc_module_end ()
static int Demux (demux_t *);
static int Control (demux_t *, int i_query, va_list args);
typedef struct smf_track_t
{
int64_t offset; /* Read offset in the file (stream_Tell) */
int64_t end; /* End offset in the file */
uint64_t next; /* Time of next message (in term of pulses) */
uint8_t running_event; /* Running (previous) event */
} mtrk_t;
static int ReadDeltaTime (stream_t *s, mtrk_t *track);
struct demux_sys_t
{
es_out_id_t *es;
date_t pts;
uint64_t pulse; /* Pulses counter */
unsigned ppqn; /* Pulses Per Quarter Note */
/* by the way, "quarter note" is "noire" in French */
unsigned trackc; /* Number of tracks */
mtrk_t trackv[]; /* Track states */
};
/*****************************************************************************
* Open: check file and initializes structures
*****************************************************************************/
static int Open (vlc_object_t * p_this)
{
demux_t *p_demux = (demux_t *)p_this;
stream_t *stream = p_demux->s;
demux_sys_t *p_sys;
const uint8_t *peek;
unsigned tracks, ppqn;
bool multitrack;
/* (Try to) parse the SMF header */
/* Header chunk always has 6 bytes payload */
if (stream_Peek (stream, &peek, 14) < 14)
return VLC_EGENERIC;
/* Skip RIFF MIDI header if present */
if (!memcmp (peek, "RIFF", 4) && !memcmp (peek + 8, "RMID", 4))
{
uint32_t riff_len = GetDWLE (peek + 4);
msg_Dbg (p_this, "detected RIFF MIDI file (%u bytes)",
(unsigned)riff_len);
if ((stream_Read (stream, NULL, 12) < 12))
return VLC_EGENERIC;
/* Look for the RIFF data chunk */
for (;;)
{
char chnk_hdr[8];
uint32_t chnk_len;
if ((riff_len < 8)
|| (stream_Read (stream, chnk_hdr, 8) < 8))
return VLC_EGENERIC;
riff_len -= 8;
chnk_len = GetDWLE (chnk_hdr + 4);
if (riff_len < chnk_len)
return VLC_EGENERIC;
riff_len -= chnk_len;
if (!memcmp (chnk_hdr, "data", 4))
break; /* found! */
if (stream_Read (stream, NULL, chnk_len) < (ssize_t)chnk_len)
return VLC_EGENERIC;
}
/* Read real SMF header. Assume RIFF data chunk length is proper. */
if (stream_Peek (stream, &peek, 14) < 14)
return VLC_EGENERIC;
}
if (memcmp (peek, "MThd\x00\x00\x00\x06", 8))
return VLC_EGENERIC;
peek += 8;
/* First word: SMF type */
switch (GetWBE (peek))
{
case 0:
multitrack = false;
break;
case 1:
multitrack = true;
break;
default:
/* We don't implement SMF2 (as do many) */
msg_Err (p_this, "unsupported SMF file type %u", GetWBE (peek));
return VLC_EGENERIC;
}
peek += 2;
/* Second word: number of tracks */
tracks = GetWBE (peek);
peek += 2;
if (!multitrack && (tracks != 1))
{
msg_Err (p_this, "invalid SMF type 0 file");
return VLC_EGENERIC;
}
msg_Dbg (p_this, "detected Standard MIDI File (type %u) with %u track(s)",
multitrack, tracks);
/* Third/last word: timing */
ppqn = GetWBE (peek);
if (ppqn & 0x8000)
{
/* FIXME */
msg_Err (p_this, "SMPTE timestamps not implemented");
return VLC_EGENERIC;
}
else
{
msg_Dbg (p_this, " %u pulses per quarter note", ppqn);
}
p_sys = malloc (sizeof (*p_sys) + (sizeof (mtrk_t) * tracks));
if (unlikely(p_sys == NULL))
return VLC_ENOMEM;
/* We've had a valid SMF header - now skip it*/
if (stream_Read (stream, NULL, 14) < 14)
goto error;
/* Default SMF tempo is 120BPM, i.e. half a second per quarter note */
date_Init (&p_sys->pts, ppqn * 2, 1);
date_Set (&p_sys->pts, 0);
p_sys->pulse = 0;
p_sys->ppqn = ppqn;
p_sys->trackc = tracks;
/* Prefetch track offsets */
for (unsigned i = 0; i < tracks; i++)
{
uint8_t head[8];
if (i > 0)
{
/* Seeking screws streaming up, but there is no way around this,
* as SMF1 tracks are performed simultaneously.
* Not a big deal as SMF1 are usually only a few kbytes anyway. */
if (stream_Seek (stream, p_sys->trackv[i - 1].end))
{
msg_Err (p_this, "cannot build SMF index (corrupted file?)");
goto error;
}
}
for (;;)
{
if (stream_Read (stream, head, 8) < 8)
{
/* FIXME: don't give up if we have at least one valid track */
msg_Err (p_this, "incomplete SMF chunk, file is corrupted");
goto error;
}
if (memcmp (head, "MTrk", 4) == 0)
break;
msg_Dbg (p_this, "skipping unknown SMF chunk");
stream_Read (stream, NULL, GetDWBE (head + 4));
}
p_sys->trackv[i].offset = stream_Tell (stream);
p_sys->trackv[i].end = p_sys->trackv[i].offset + GetDWBE (head + 4);
p_sys->trackv[i].next = 0;
ReadDeltaTime (stream, p_sys->trackv + i);
p_sys->trackv[i].running_event = 0xF6;
/* Why 0xF6 (Tuning Calibration)?
* Because it has zero bytes of data, so the parser will detect the
* error if the first event uses running status. */
}
es_format_t fmt;
es_format_Init (&fmt, AUDIO_ES, VLC_CODEC_MIDI);
fmt.audio.i_channels = 2;
fmt.audio.i_rate = 44100; /* dummy value */
p_sys->es = es_out_Add (p_demux->out, &fmt);
p_demux->pf_demux = Demux;
p_demux->pf_control = Control;
p_demux->p_sys = p_sys;
return VLC_SUCCESS;
error:
free (p_sys);
return VLC_EGENERIC;
}
/**
* Releases allocate resources.
*/
static void Close (vlc_object_t * p_this)
{
demux_t *p_demux = (demux_t *)p_this;
demux_sys_t *p_sys = p_demux->p_sys;
free (p_sys);
}
/**
* Reads MIDI variable length (7, 14, 21 or 28 bits) integer.
* @return read value, or -1 on EOF/error.
......@@ -278,6 +56,13 @@ static int32_t ReadVarInt (stream_t *s)
return -1;
}
typedef struct smf_track_t
{
int64_t offset; /* Read offset in the file (stream_Tell) */
int64_t end; /* End offset in the file */
uint64_t next; /* Time of next message (in term of pulses) */
uint8_t running_event; /* Running (previous) event */
} mtrk_t;
/**
* Reads (delta) time from the next event of a given track.
......@@ -305,6 +90,18 @@ static int ReadDeltaTime (stream_t *s, mtrk_t *track)
return 0;
}
struct demux_sys_t
{
es_out_id_t *es;
date_t pts;
uint64_t pulse; /* Pulses counter */
unsigned ppqn; /* Pulses Per Quarter Note */
/* by the way, "quarter note" is "noire" in French */
unsigned trackc; /* Number of tracks */
mtrk_t trackv[]; /* Track states */
};
/**
* Non-MIDI Meta events handler
......@@ -453,8 +250,6 @@ int HandleMeta (demux_t *p_demux, mtrk_t *tr)
return ret;
}
static
int HandleMessage (demux_t *p_demux, mtrk_t *tr)
{
......@@ -617,7 +412,6 @@ static int Demux (demux_t *p_demux)
return 1;
}
/*****************************************************************************
* Control:
*****************************************************************************/
......@@ -642,3 +436,192 @@ static int Control (demux_t *p_demux, int i_query, va_list args)
}
return VLC_EGENERIC;
}
/**
* Probes file format and starts demuxing.
*/
static int Open (vlc_object_t *obj)
{
demux_t *demux = (demux_t *)obj;
stream_t *stream = demux->s;
const uint8_t *peek;
bool multitrack;
/* (Try to) parse the SMF header */
/* Header chunk always has 6 bytes payload */
if (stream_Peek (stream, &peek, 14) < 14)
return VLC_EGENERIC;
/* Skip RIFF MIDI header if present */
if (!memcmp (peek, "RIFF", 4) && !memcmp (peek + 8, "RMID", 4))
{
uint32_t riff_len = GetDWLE (peek + 4);
msg_Dbg (demux, "detected RIFF MIDI file (%"PRIu32" bytes)", riff_len);
if ((stream_Read (stream, NULL, 12) < 12))
return VLC_EGENERIC;
/* Look for the RIFF data chunk */
for (;;)
{
char chnk_hdr[8];
uint32_t chnk_len;
if ((riff_len < 8)
|| (stream_Read (stream, chnk_hdr, 8) < 8))
return VLC_EGENERIC;
riff_len -= 8;
chnk_len = GetDWLE (chnk_hdr + 4);
if (riff_len < chnk_len)
return VLC_EGENERIC;
riff_len -= chnk_len;
if (!memcmp (chnk_hdr, "data", 4))
break; /* found! */
if (stream_Read (stream, NULL, chnk_len) < (ssize_t)chnk_len)
return VLC_EGENERIC;
}
/* Read real SMF header. Assume RIFF data chunk length is proper. */
if (stream_Peek (stream, &peek, 14) < 14)
return VLC_EGENERIC;
}
if (memcmp (peek, "MThd\x00\x00\x00\x06", 8))
return VLC_EGENERIC;
peek += 8;
/* First word: SMF type */
switch (GetWBE (peek))
{
case 0:
multitrack = false;
break;
case 1:
multitrack = true;
break;
default:
/* We don't implement SMF2 (as do many) */
msg_Err (demux, "unsupported SMF file type %u", GetWBE (peek));
return VLC_EGENERIC;
}
peek += 2;
/* Second word: number of tracks */
unsigned tracks = GetWBE (peek);
peek += 2;
if (!multitrack && (tracks != 1))
{
msg_Err (demux, "invalid SMF type 0 file");
return VLC_EGENERIC;
}
msg_Dbg (demux, "detected Standard MIDI File (type %u) with %u track(s)",
multitrack, tracks);
/* Third/last word: timing */
unsigned ppqn = GetWBE (peek);
if (ppqn & 0x8000)
{ /* FIXME */
msg_Err (demux, "SMPTE timestamps not implemented");
return VLC_EGENERIC;
}
else
{
msg_Dbg (demux, " %u pulses per quarter note", ppqn);
}
demux_sys_t *sys = malloc (sizeof (*sys) + (sizeof (mtrk_t) * tracks));
if (unlikely(sys == NULL))
return VLC_ENOMEM;
/* We've had a valid SMF header - now skip it*/
if (stream_Read (stream, NULL, 14) < 14)
goto error;
/* Default SMF tempo is 120BPM, i.e. half a second per quarter note */
date_Init (&sys->pts, ppqn * 2, 1);
date_Set (&sys->pts, 0);
sys->pulse = 0;
sys->ppqn = ppqn;
sys->trackc = tracks;
/* Prefetch track offsets */
for (unsigned i = 0; i < tracks; i++)
{
uint8_t head[8];
if (i > 0)
{
/* Seeking screws streaming up, but there is no way around this,
* as SMF1 tracks are performed simultaneously.
* Not a big deal as SMF1 are usually only a few kbytes anyway. */
if (stream_Seek (stream, sys->trackv[i - 1].end))
{
msg_Err (demux, "cannot build SMF index (corrupted file?)");
goto error;
}
}
for (;;)
{
if (stream_Read (stream, head, 8) < 8)
{
/* FIXME: don't give up if we have at least one valid track */
msg_Err (demux, "incomplete SMF chunk, file is corrupted");
goto error;
}
if (memcmp (head, "MTrk", 4) == 0)
break;
msg_Dbg (demux, "skipping unknown SMF chunk");
stream_Read (stream, NULL, GetDWBE (head + 4));
}
sys->trackv[i].offset = stream_Tell (stream);
sys->trackv[i].end = sys->trackv[i].offset + GetDWBE (head + 4);
sys->trackv[i].next = 0;
ReadDeltaTime (stream, sys->trackv + i);
sys->trackv[i].running_event = 0xF6;
/* Why 0xF6 (Tuning Calibration)?
* Because it has zero bytes of data, so the parser will detect the
* error if the first event uses running status. */
}
es_format_t fmt;
es_format_Init (&fmt, AUDIO_ES, VLC_CODEC_MIDI);
fmt.audio.i_channels = 2;
fmt.audio.i_rate = 44100; /* dummy value */
sys->es = es_out_Add (demux->out, &fmt);
demux->pf_demux = Demux;
demux->pf_control = Control;
demux->p_sys = sys;
return VLC_SUCCESS;
error:
free (sys);
return VLC_EGENERIC;
}
/**
* Releases allocate resources.
*/
static void Close (vlc_object_t * p_this)
{
demux_t *p_demux = (demux_t *)p_this;
demux_sys_t *p_sys = p_demux->p_sys;
free (p_sys);
}
vlc_module_begin ()
set_description (N_("SMF demuxer"))
set_category (CAT_INPUT)
set_subcategory (SUBCAT_INPUT_DEMUX)
set_capability ("demux", 20)
set_callbacks (Open, Close)
vlc_module_end ()
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