fluidsynth.c
author Sam Lantinga <slouken@libsdl.org>
Sat, 31 Dec 2011 10:27:48 -0500
changeset 518 8bc9b5fd2aae
parent 506 586ae09f8176
child 521 565549e046b0
permissions -rw-r--r--
Happy New Year!
     1 /*
     2   SDL_mixer:  An audio mixer library based on the SDL library
     3   Copyright (C) 1997-2012 Sam Lantinga <slouken@libsdl.org>
     4 
     5   This software is provided 'as-is', without any express or implied
     6   warranty.  In no event will the authors be held liable for any damages
     7   arising from the use of this software.
     8 
     9   Permission is granted to anyone to use this software for any purpose,
    10   including commercial applications, and to alter it and redistribute it
    11   freely, subject to the following restrictions:
    12 
    13   1. The origin of this software must not be misrepresented; you must not
    14      claim that you wrote the original software. If you use this software
    15      in a product, an acknowledgment in the product documentation would be
    16      appreciated but is not required.
    17   2. Altered source versions must be plainly marked as such, and must not be
    18      misrepresented as being the original software.
    19   3. This notice may not be removed or altered from any source distribution.
    20 
    21   James Le Cuirot
    22   chewi@aura-online.co.uk
    23 */
    24 
    25 #include "fluidsynth.h"
    26 #include "SDL_mixer.h"
    27 #include <stdio.h>
    28 #include <sys/types.h>
    29 
    30 static Uint16 format;
    31 static Uint8 channels;
    32 static int freq;
    33 
    34 int fluidsynth_check_soundfont(const char *path, void *data)
    35 {
    36 	FILE *file = fopen(path, "r");
    37 
    38 	if (file) {
    39 		fclose(file);
    40 		return 1;
    41 	} else {
    42 		Mix_SetError("Failed to access the SoundFont %s", path);
    43 		return 0;
    44 	}
    45 }
    46 
    47 int fluidsynth_load_soundfont(const char *path, void *data)
    48 {
    49 	/* If this fails, it's too late to try Timidity so pray that at least one works. */
    50 	fluidsynth.fluid_synth_sfload((fluid_synth_t*) data, path, 1);
    51 	return 1;
    52 }
    53 
    54 int fluidsynth_init(SDL_AudioSpec *mixer)
    55 {
    56 	if (!Mix_EachSoundFont(fluidsynth_check_soundfont, NULL))
    57 		return -1;
    58 
    59 	format = mixer->format;
    60 	channels = mixer->channels;
    61 	freq = mixer->freq;
    62 
    63 	return 0;
    64 }
    65 
    66 FluidSynthMidiSong *fluidsynth_loadsong_common(int (*function)(FluidSynthMidiSong*, void*), void *data)
    67 {
    68 	FluidSynthMidiSong *song;
    69 	fluid_settings_t *settings = NULL;
    70 
    71 	if ((song = malloc(sizeof(FluidSynthMidiSong)))) {
    72 		memset(song, 0, sizeof(FluidSynthMidiSong));
    73 
    74 		if (SDL_BuildAudioCVT(&song->convert, AUDIO_S16, 2, freq, format, channels, freq) >= 0) {
    75 			if ((settings = fluidsynth.new_fluid_settings())) {
    76 				fluidsynth.fluid_settings_setnum(settings, "synth.sample-rate", (double) freq);
    77 
    78 				if ((song->synth = fluidsynth.new_fluid_synth(settings))) {
    79 					if (Mix_EachSoundFont(fluidsynth_load_soundfont, (void*) song->synth)) {
    80 						if ((song->player = fluidsynth.new_fluid_player(song->synth))) {
    81 							if (function(song, data)) return song;
    82 							fluidsynth.delete_fluid_player(song->player);
    83 						} else {
    84 							Mix_SetError("Failed to create FluidSynth player");
    85 						}
    86 					}
    87 					fluidsynth.delete_fluid_synth(song->synth);
    88 				} else {
    89 					Mix_SetError("Failed to create FluidSynth synthesizer");
    90 				}
    91 				fluidsynth.delete_fluid_settings(settings);
    92 			} else {
    93 				Mix_SetError("Failed to create FluidSynth settings");
    94 			}
    95 		} else {
    96 			Mix_SetError("Failed to set up audio conversion");
    97 		}
    98 		free(song);
    99 	} else {
   100 		Mix_SetError("Insufficient memory for song");
   101 	}
   102 	return NULL;
   103 }
   104 
   105 int fluidsynth_loadsong_internal(FluidSynthMidiSong *song, void *data)
   106 {
   107 	const char* path = (const char*) data;
   108 
   109 	if (fluidsynth.fluid_player_add(song->player, path) == FLUID_OK) {
   110 		return 1;
   111 	} else {
   112 		Mix_SetError("FluidSynth failed to load %s", path);
   113 		return 0;
   114 	}
   115 }
   116 
   117 int fluidsynth_loadsong_RW_internal(FluidSynthMidiSong *song, void *data)
   118 {
   119 	off_t offset;
   120 	size_t size;
   121 	char *buffer;
   122 	SDL_RWops *rw = (SDL_RWops*) data;
   123 
   124 	offset = SDL_RWtell(rw);
   125 	SDL_RWseek(rw, 0, RW_SEEK_END);
   126 	size = SDL_RWtell(rw) - offset;
   127 	SDL_RWseek(rw, offset, RW_SEEK_SET);
   128 
   129 	if ((buffer = (char*) malloc(size))) {
   130 		if(SDL_RWread(rw, buffer, size, 1) == 1) {
   131 			if (fluidsynth.fluid_player_add_mem(song->player, buffer, size) == FLUID_OK) {
   132 				return 1;
   133 			} else {
   134 				Mix_SetError("FluidSynth failed to load in-memory song");
   135 			}
   136 		} else {
   137 			Mix_SetError("Failed to read in-memory song");
   138 		}
   139 		free(buffer);
   140 	} else {
   141 		Mix_SetError("Insufficient memory for song");
   142 	}
   143 	return 0;
   144 }
   145 
   146 FluidSynthMidiSong *fluidsynth_loadsong(const char *midifile)
   147 {
   148 	return fluidsynth_loadsong_common(fluidsynth_loadsong_internal, (void*) midifile);
   149 }
   150 
   151 FluidSynthMidiSong *fluidsynth_loadsong_RW(SDL_RWops *rw)
   152 {
   153 	return fluidsynth_loadsong_common(fluidsynth_loadsong_RW_internal, (void*) rw);
   154 }
   155 
   156 void fluidsynth_freesong(FluidSynthMidiSong *song)
   157 {
   158 	if (!song) return;
   159 	fluidsynth.delete_fluid_player(song->player);
   160 	fluidsynth.delete_fluid_settings(fluidsynth.fluid_synth_get_settings(song->synth));
   161 	fluidsynth.delete_fluid_synth(song->synth);
   162 	free(song);
   163 }
   164 
   165 void fluidsynth_start(FluidSynthMidiSong *song)
   166 {
   167 	fluidsynth.fluid_player_set_loop(song->player, 1);
   168 	fluidsynth.fluid_player_play(song->player);
   169 }
   170 
   171 void fluidsynth_stop(FluidSynthMidiSong *song)
   172 {
   173 	fluidsynth.fluid_player_stop(song->player);
   174 }
   175 
   176 int fluidsynth_active(FluidSynthMidiSong *song)
   177 {
   178 	return fluidsynth.fluid_player_get_status(song->player) == FLUID_PLAYER_PLAYING ? 1 : 0;
   179 }
   180 
   181 void fluidsynth_setvolume(FluidSynthMidiSong *song, int volume)
   182 {
   183 	/* FluidSynth's default is 0.2. Make 0.8 the maximum. */
   184 	fluidsynth.fluid_synth_set_gain(song->synth, (float) (volume * 0.00625));
   185 }
   186 
   187 int fluidsynth_playsome(FluidSynthMidiSong *song, void *dest, int dest_len)
   188 {
   189 	int result = -1;
   190 	int frames = dest_len / channels / ((format & 0xFF) / 8);
   191 	int src_len = frames * 4; /* 16-bit stereo */
   192 	void *src = dest;
   193 
   194 	if (dest_len < src_len) {
   195 		if (!(src = malloc(src_len))) {
   196 			Mix_SetError("Insufficient memory for audio conversion");
   197 			return result;
   198 		}
   199 	}
   200 
   201 	if (fluidsynth.fluid_synth_write_s16(song->synth, frames, src, 0, 2, src, 1, 2) != FLUID_OK) {
   202 		Mix_SetError("Error generating FluidSynth audio");
   203 		goto finish;
   204 	}
   205 
   206 	song->convert.buf = src;
   207 	song->convert.len = src_len;
   208 
   209 	if (SDL_ConvertAudio(&song->convert) < 0) {
   210 		Mix_SetError("Error during audio conversion");
   211 		goto finish;
   212 	}
   213 
   214 	if (src != dest)
   215 		memcpy(dest, src, dest_len);
   216 
   217 	result = 0;
   218 
   219 finish:
   220 	if (src != dest)
   221 		free(src);
   222 
   223 	return result;
   224 }