fluidsynth.c
author Ozkan Sezer <sezeroz@gmail.com>
Sun, 07 Oct 2018 01:43:02 +0300
branchSDL-1.2
changeset 881 6bf9b92cfad9
parent 585 f2943eac3fd7
child 887 e49459791ae8
permissions -rw-r--r--
backport fix for bug #3018. (from 2.0 branch commit fe757163b8f7).
     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 #ifdef USE_FLUIDSYNTH_MIDI
    26 
    27 #include <stdio.h>
    28 #include <sys/types.h>
    29 
    30 #include "SDL_mixer.h"
    31 #include "fluidsynth.h"
    32 
    33 static Uint16 format;
    34 static Uint8 channels;
    35 static int freq;
    36 
    37 int fluidsynth_check_soundfont(const char *path, void *data)
    38 {
    39 	FILE *file = fopen(path, "r");
    40 
    41 	if (file) {
    42 		fclose(file);
    43 		return 1;
    44 	} else {
    45 		Mix_SetError("Failed to access the SoundFont %s", path);
    46 		return 0;
    47 	}
    48 }
    49 
    50 int fluidsynth_load_soundfont(const char *path, void *data)
    51 {
    52 	/* If this fails, it's too late to try Timidity so pray that at least one works. */
    53 	fluidsynth.fluid_synth_sfload((fluid_synth_t*) data, path, 1);
    54 	return 1;
    55 }
    56 
    57 int fluidsynth_init(SDL_AudioSpec *mixer)
    58 {
    59 	if (!Mix_EachSoundFont(fluidsynth_check_soundfont, NULL))
    60 		return -1;
    61 
    62 	format = mixer->format;
    63 	channels = mixer->channels;
    64 	freq = mixer->freq;
    65 
    66 	return 0;
    67 }
    68 
    69 static FluidSynthMidiSong *fluidsynth_loadsong_common(int (*function)(FluidSynthMidiSong*, void*), void *data)
    70 {
    71 	FluidSynthMidiSong *song;
    72 	fluid_settings_t *settings = NULL;
    73 
    74 	if (!Mix_Init(MIX_INIT_FLUIDSYNTH)) {
    75 		return NULL;
    76 	}
    77 
    78 	if ((song = SDL_malloc(sizeof(FluidSynthMidiSong)))) {
    79 		memset(song, 0, sizeof(FluidSynthMidiSong));
    80 
    81 		if (SDL_BuildAudioCVT(&song->convert, AUDIO_S16, 2, freq, format, channels, freq) >= 0) {
    82 			if ((settings = fluidsynth.new_fluid_settings())) {
    83 				fluidsynth.fluid_settings_setnum(settings, "synth.sample-rate", (double) freq);
    84 
    85 				if ((song->synth = fluidsynth.new_fluid_synth(settings))) {
    86 					if (Mix_EachSoundFont(fluidsynth_load_soundfont, (void*) song->synth)) {
    87 						if ((song->player = fluidsynth.new_fluid_player(song->synth))) {
    88 							if (function(song, data)) return song;
    89 							fluidsynth.delete_fluid_player(song->player);
    90 						} else {
    91 							Mix_SetError("Failed to create FluidSynth player");
    92 						}
    93 					}
    94 					fluidsynth.delete_fluid_synth(song->synth);
    95 				} else {
    96 					Mix_SetError("Failed to create FluidSynth synthesizer");
    97 				}
    98 				fluidsynth.delete_fluid_settings(settings);
    99 			} else {
   100 				Mix_SetError("Failed to create FluidSynth settings");
   101 			}
   102 		} else {
   103 			Mix_SetError("Failed to set up audio conversion");
   104 		}
   105 		SDL_free(song);
   106 	} else {
   107 		Mix_SetError("Insufficient memory for song");
   108 	}
   109 	return NULL;
   110 }
   111 
   112 static int fluidsynth_loadsong_RW_internal(FluidSynthMidiSong *song, void *data)
   113 {
   114 	off_t offset;
   115 	size_t size;
   116 	char *buffer;
   117 	SDL_RWops *rw = (SDL_RWops*) data;
   118 
   119 	offset = SDL_RWtell(rw);
   120 	SDL_RWseek(rw, 0, RW_SEEK_END);
   121 	size = SDL_RWtell(rw) - offset;
   122 	SDL_RWseek(rw, offset, RW_SEEK_SET);
   123 
   124 	if ((buffer = (char*) SDL_malloc(size))) {
   125 		if(SDL_RWread(rw, buffer, size, 1) == 1) {
   126 			if (fluidsynth.fluid_player_add_mem(song->player, buffer, size) == FLUID_OK) {
   127 				SDL_free(buffer);
   128 				return 1;
   129 			} else {
   130 				Mix_SetError("FluidSynth failed to load in-memory song");
   131 			}
   132 		} else {
   133 			Mix_SetError("Failed to read in-memory song");
   134 		}
   135 		SDL_free(buffer);
   136 	} else {
   137 		Mix_SetError("Insufficient memory for song");
   138 	}
   139 	return 0;
   140 }
   141 
   142 FluidSynthMidiSong *fluidsynth_loadsong_RW(SDL_RWops *rw, int freerw)
   143 {
   144 	FluidSynthMidiSong *song;
   145 
   146 	song = fluidsynth_loadsong_common(fluidsynth_loadsong_RW_internal, (void*) rw);
   147 	if (freerw) {
   148 		SDL_RWclose(rw);
   149 	}
   150 	return song;
   151 }
   152 
   153 void fluidsynth_freesong(FluidSynthMidiSong *song)
   154 {
   155 	if (!song) return;
   156 	fluidsynth.delete_fluid_player(song->player);
   157 	fluidsynth.delete_fluid_settings(fluidsynth.fluid_synth_get_settings(song->synth));
   158 	fluidsynth.delete_fluid_synth(song->synth);
   159 	SDL_free(song);
   160 }
   161 
   162 void fluidsynth_start(FluidSynthMidiSong *song)
   163 {
   164 	fluidsynth.fluid_player_set_loop(song->player, 1);
   165 	fluidsynth.fluid_player_play(song->player);
   166 }
   167 
   168 void fluidsynth_stop(FluidSynthMidiSong *song)
   169 {
   170 	fluidsynth.fluid_player_stop(song->player);
   171 }
   172 
   173 int fluidsynth_active(FluidSynthMidiSong *song)
   174 {
   175 	return fluidsynth.fluid_player_get_status(song->player) == FLUID_PLAYER_PLAYING ? 1 : 0;
   176 }
   177 
   178 void fluidsynth_setvolume(FluidSynthMidiSong *song, int volume)
   179 {
   180 	/* FluidSynth's default is 0.2. Make 1.2 the maximum. */
   181 	fluidsynth.fluid_synth_set_gain(song->synth, (float) (volume * 1.2 / MIX_MAX_VOLUME));
   182 }
   183 
   184 int fluidsynth_playsome(FluidSynthMidiSong *song, void *dest, int dest_len)
   185 {
   186 	int result = -1;
   187 	int frames = dest_len / channels / ((format & 0xFF) / 8);
   188 	int src_len = frames * 4; /* 16-bit stereo */
   189 	void *src = dest;
   190 
   191 	if (dest_len < src_len) {
   192 		if (!(src = SDL_malloc(src_len))) {
   193 			Mix_SetError("Insufficient memory for audio conversion");
   194 			return result;
   195 		}
   196 	}
   197 
   198 	if (fluidsynth.fluid_synth_write_s16(song->synth, frames, src, 0, 2, src, 1, 2) != FLUID_OK) {
   199 		Mix_SetError("Error generating FluidSynth audio");
   200 		goto finish;
   201 	}
   202 
   203 	song->convert.buf = src;
   204 	song->convert.len = src_len;
   205 
   206 	if (SDL_ConvertAudio(&song->convert) < 0) {
   207 		Mix_SetError("Error during audio conversion");
   208 		goto finish;
   209 	}
   210 
   211 	if (src != dest)
   212 		memcpy(dest, src, dest_len);
   213 
   214 	result = 0;
   215 
   216 finish:
   217 	if (src != dest)
   218 		SDL_free(src);
   219 
   220 	return result;
   221 }
   222 
   223 #endif /* USE_FLUIDSYNTH_MIDI */