Mercurial > SDL_sound_CoreAudio
annotate SDL_sound_internal.h @ 25:4acb5260d684
Made the SDL audio callback much more robust.
| author | Ryan C. Gordon <icculus@icculus.org> |
|---|---|
| date | Wed, 19 Sep 2001 14:05:36 +0000 |
| parents | 2888101dcf98 |
| children | eeb874083218 |
| rev | line source |
|---|---|
| 4 | 1 /* |
| 2 * SDL_sound -- An abstract sound format decoding API. | |
| 3 * Copyright (C) 2001 Ryan C. Gordon. | |
| 4 * | |
| 5 * This library is free software; you can redistribute it and/or | |
| 6 * modify it under the terms of the GNU Lesser General Public | |
| 7 * License as published by the Free Software Foundation; either | |
| 8 * version 2.1 of the License, or (at your option) any later version. | |
| 9 * | |
| 10 * This library is distributed in the hope that it will be useful, | |
| 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 * Lesser General Public License for more details. | |
| 14 * | |
| 15 * You should have received a copy of the GNU Lesser General Public | |
| 16 * License along with this library; if not, write to the Free Software | |
| 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
| 18 */ | |
| 19 | |
| 20 /* | |
| 21 * Internal function/structure declaration. Do NOT include in your | |
| 22 * application. | |
| 23 * | |
| 24 * Please see the file LICENSE in the source's root directory. | |
| 25 * | |
| 26 * This file written by Ryan C. Gordon. (icculus@clutteredmind.org) | |
| 27 */ | |
| 28 | |
| 29 #ifndef _INCLUDE_SDL_SOUND_INTERNAL_H_ | |
| 30 #define _INCLUDE_SDL_SOUND_INTERNAL_H_ | |
| 31 | |
| 32 #ifndef __SDL_SOUND_INTERNAL__ | |
| 33 #error Do not include this header from your applications. | |
| 34 #endif | |
| 35 | |
| 36 #include "SDL.h" | |
| 37 | |
|
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2888101dcf98
Added _D(()) macro, decoder_private field, and changed read() method from
Ryan C. Gordon <icculus@icculus.org>
parents:
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changeset
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38 #if (defined DEBUG_CHATTER) |
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2888101dcf98
Added _D(()) macro, decoder_private field, and changed read() method from
Ryan C. Gordon <icculus@icculus.org>
parents:
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changeset
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39 #define _D(x) printf x |
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2888101dcf98
Added _D(()) macro, decoder_private field, and changed read() method from
Ryan C. Gordon <icculus@icculus.org>
parents:
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diff
changeset
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40 #else |
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2888101dcf98
Added _D(()) macro, decoder_private field, and changed read() method from
Ryan C. Gordon <icculus@icculus.org>
parents:
4
diff
changeset
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41 #define _D(x) |
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2888101dcf98
Added _D(()) macro, decoder_private field, and changed read() method from
Ryan C. Gordon <icculus@icculus.org>
parents:
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diff
changeset
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42 #endif |
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2888101dcf98
Added _D(()) macro, decoder_private field, and changed read() method from
Ryan C. Gordon <icculus@icculus.org>
parents:
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diff
changeset
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43 |
| 4 | 44 typedef struct __SOUND_DECODERFUNCTIONS__ |
| 45 { | |
| 46 /* This is a block of info about your decoder. See SDL_sound.h. */ | |
| 47 const Sound_DecoderInfo info; | |
| 48 | |
| 49 /* | |
| 50 * Returns non-zero if (sample) has a valid fileformat that this | |
| 51 * driver can handle. Zero if this driver can NOT handle the data. | |
| 52 * | |
| 53 * Extension, which may be NULL, is just a hint as to the form of | |
| 54 * data that is being passed in. Most decoders should determine if | |
| 55 * they can handle the data by the data itself, but others, like | |
| 56 * the raw data handler, need this hint to know if they should | |
| 57 * accept the data in the first place. | |
| 58 * | |
| 59 * (sample)'s (opaque) field should be cast to a Sound_SampleInternal | |
| 60 * pointer: | |
| 61 * | |
| 62 * Sound_SampleInternal *internal; | |
| 63 * internal = (Sound_SampleInternal *) sample->opaque; | |
| 64 * | |
| 65 * Certain fields of sample will be filled in for the decoder before | |
| 66 * this call, and others should be filled in by the decoder. Some | |
| 67 * fields are offlimits, and should NOT be modified. The list: | |
| 68 * | |
| 69 * in Sound_SampleInternal section: | |
| 70 * Sound_Sample *next; (offlimits) | |
| 71 * Sound_Sample *prev; (offlimits) | |
| 72 * SDL_RWops *rw; (can use, but do NOT close it) | |
| 73 * const Sound_DecoderFunctions *funcs; (that's this structure) | |
| 74 * SDL_AudioCVT sdlcvt; (offlimits) | |
| 75 * void *buffer; (offlimits until read() method) | |
| 76 * Uint32 buffer_size; (offlimits until read() method) | |
|
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2888101dcf98
Added _D(()) macro, decoder_private field, and changed read() method from
Ryan C. Gordon <icculus@icculus.org>
parents:
4
diff
changeset
|
77 * void *decoder_private; (read and write access) |
| 4 | 78 * |
| 79 * in rest of Sound_Sample: | |
| 80 * void *opaque; (this was internal section, above) | |
| 81 * const Sound_DecoderInfo *decoder; (read only) | |
| 82 * Sound_AudioInfo desired; (read only, usually not needed here) | |
| 83 * Sound_AudioInfo actual; (please fill this in) | |
| 84 * void *buffer; (offlimits) | |
| 85 * Uint32 buffer_size; (offlimits) | |
| 86 * Sound_SampleFlags flags; (set appropriately) | |
| 87 */ | |
| 88 int (*open)(Sound_Sample *sample, const char *ext); | |
| 89 | |
| 90 /* | |
| 91 * Clean up. SDL_sound is done with this sample, so the decoder should | |
| 92 * clean up any resources it allocated. Anything that wasn't | |
| 93 * explicitly allocated by the decoder should be LEFT ALONE, since | |
| 94 * the higher-level SDL_sound layer will clean up its own mess. | |
| 95 */ | |
| 96 void (*close)(Sound_Sample *sample); | |
| 97 | |
| 98 /* | |
| 99 * Get more data from (sample). The decoder should get a pointer to | |
| 100 * the internal structure... | |
| 101 * | |
| 102 * Sound_SampleInternal *internal; | |
| 103 * internal = (Sound_SampleInternal *) sample->opaque; | |
| 104 * | |
| 105 * ...and then start decoding. Fill in up to internal->buffer_size | |
| 106 * bytes of decoded sound in the space pointed to by | |
| 107 * internal->buffer. The encoded data is read in from internal->rw. | |
| 108 * Data should be decoded in the format specified during the | |
| 109 * decoder's open() method in the sample->actual field. The | |
| 110 * conversion to the desired format is done at a higher level. | |
| 111 * | |
| 112 * The return value is the number of bytes decoded into | |
| 113 * internal->buffer, which can be no more than internal->buffer_size, | |
| 114 * but can be less. If it is less, you should set a state flag: | |
| 115 * | |
| 116 * If there's just no more data (end of file, etc), then do: | |
| 117 * sample->flags |= SOUND_SAMPLEFLAG_EOF; | |
| 118 * | |
| 119 * If there's an unrecoverable error, then do: | |
| 120 * Sound_SetError(ERR_EXPLAIN_WHAT_WENT_WRONG); | |
| 121 * sample->flags |= SOUND_SAMPLEFLAG_ERROR; | |
| 122 * | |
| 123 * If there's more data, but you'd have to block for considerable | |
| 124 * amounts of time to get at it, or there's a recoverable error, | |
| 125 * then do: | |
| 126 * Sound_SetError(ERR_EXPLAIN_WHAT_WENT_WRONG); | |
| 127 * sample->flags |= SOUND_SAMPLEFLAG_EAGAIN; | |
| 128 * | |
| 129 * SDL_sound will not call your read() method for any samples with | |
| 130 * SOUND_SAMPLEFLAG_EOF or SOUND_SAMPLEFLAG_ERROR set. The | |
| 131 * SOUND_SAMPLEFLAG_EAGAIN flag is reset before each call to this | |
| 132 * method. | |
| 133 */ | |
|
12
2888101dcf98
Added _D(()) macro, decoder_private field, and changed read() method from
Ryan C. Gordon <icculus@icculus.org>
parents:
4
diff
changeset
|
134 Uint32 (*read)(Sound_Sample *sample); |
| 4 | 135 } Sound_DecoderFunctions; |
| 136 | |
| 137 | |
| 138 typedef struct __SOUND_SAMPLEINTERNAL__ | |
| 139 { | |
| 140 Sound_Sample *next; | |
| 141 Sound_Sample *prev; | |
| 142 SDL_RWops *rw; | |
| 143 const Sound_DecoderFunctions *funcs; | |
| 144 SDL_AudioCVT sdlcvt; | |
| 145 void *buffer; | |
| 146 Uint32 buffer_size; | |
|
12
2888101dcf98
Added _D(()) macro, decoder_private field, and changed read() method from
Ryan C. Gordon <icculus@icculus.org>
parents:
4
diff
changeset
|
147 void *decoder_private; |
| 4 | 148 } Sound_SampleInternal; |
| 149 | |
| 150 | |
| 151 | |
| 152 /* error messages... */ | |
| 153 #define ERR_IS_INITIALIZED "Already initialized" | |
| 154 #define ERR_NOT_INITIALIZED "Not initialized" | |
| 155 #define ERR_INVALID_ARGUMENT "Invalid argument" | |
| 156 #define ERR_OUT_OF_MEMORY "Out of memory" | |
| 157 #define ERR_NOT_SUPPORTED "Operation not supported" | |
| 158 #define ERR_UNSUPPORTED_FORMAT "Sound format unsupported" | |
| 159 #define ERR_NOT_A_HANDLE "Not a file handle" | |
| 160 #define ERR_NO_SUCH_FILE "No such file" | |
| 161 #define ERR_PAST_EOF "Past end of file" | |
| 162 #define ERR_IO_ERROR "I/O error" | |
| 163 #define ERR_COMPRESSION "(De)compression error" | |
| 164 #define ERR_PREV_ERROR "Previous decoding already caused an error" | |
| 165 #define ERR_PREV_EOF "Previous decoding already triggered EOF" | |
| 166 | |
| 167 /* | |
| 168 * Call this to set the message returned by Sound_GetError(). | |
| 169 * Please only use the ERR_* constants above, or add new constants to the | |
| 170 * above group, but I want these all in one place. | |
| 171 * | |
| 172 * Calling this with a NULL argument is a safe no-op. | |
| 173 */ | |
| 174 void Sound_SetError(const char *err); | |
| 175 | |
| 176 | |
| 177 /* | |
| 178 * Use this if you need a cross-platform stricmp(). | |
| 179 */ | |
| 180 int __Sound_strcasecmp(const char *x, const char *y); | |
| 181 | |
| 182 | |
| 183 /* These get used all over for lessening code clutter. */ | |
| 184 #define BAIL_MACRO(e, r) { Sound_SetError(e); return r; } | |
| 185 #define BAIL_IF_MACRO(c, e, r) if (c) { Sound_SetError(e); return r; } | |
| 186 | |
| 187 | |
| 188 | |
| 189 | |
| 190 /*--------------------------------------------------------------------------*/ | |
| 191 /*--------------------------------------------------------------------------*/ | |
| 192 /*------------ ----------------*/ | |
| 193 /*------------ You MUST implement the following functions ----------------*/ | |
| 194 /*------------ if porting to a new platform. ----------------*/ | |
| 195 /*------------ (see platform/unix.c for an example) ----------------*/ | |
| 196 /*------------ ----------------*/ | |
| 197 /*--------------------------------------------------------------------------*/ | |
| 198 /*--------------------------------------------------------------------------*/ | |
| 199 | |
| 200 | |
| 201 /* (None, right now.) */ | |
| 202 | |
| 203 | |
| 204 #ifdef __cplusplus | |
| 205 extern "C" { | |
| 206 #endif | |
| 207 | |
| 208 #endif /* defined _INCLUDE_SDL_SOUND_INTERNAL_H_ */ | |
| 209 | |
| 210 /* end of SDL_sound_internal.h ... */ | |
| 211 |