e14743d1 |
1 | /* |
2 | SDL - Simple DirectMedia Layer |
3 | Copyright (C) 1997-2009 Sam Lantinga |
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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
18 | |
19 | Sam Lantinga |
20 | slouken@libsdl.org |
21 | |
22 | This file written by Ryan C. Gordon (icculus@icculus.org) |
23 | */ |
24 | #include "SDL_config.h" |
25 | |
26 | /* Output raw audio data to a file. */ |
27 | |
28 | #if HAVE_STDIO_H |
29 | #include <stdio.h> |
30 | #endif |
31 | |
32 | #include "SDL_rwops.h" |
33 | #include "SDL_timer.h" |
34 | #include "SDL_audio.h" |
35 | #include "../SDL_audiomem.h" |
36 | #include "../SDL_audio_c.h" |
37 | #include "../SDL_audiodev_c.h" |
38 | #include "SDL_diskaudio.h" |
39 | |
40 | /* The tag name used by DISK audio */ |
41 | #define DISKAUD_DRIVER_NAME "disk" |
42 | |
43 | /* environment variables and defaults. */ |
44 | #define DISKENVR_OUTFILE "SDL_DISKAUDIOFILE" |
45 | #define DISKDEFAULT_OUTFILE "sdlaudio.raw" |
46 | #define DISKENVR_WRITEDELAY "SDL_DISKAUDIODELAY" |
47 | #define DISKDEFAULT_WRITEDELAY 150 |
48 | |
49 | /* Audio driver functions */ |
50 | static int DISKAUD_OpenAudio(_THIS, SDL_AudioSpec *spec); |
51 | static void DISKAUD_WaitAudio(_THIS); |
52 | static void DISKAUD_PlayAudio(_THIS); |
53 | static Uint8 *DISKAUD_GetAudioBuf(_THIS); |
54 | static void DISKAUD_CloseAudio(_THIS); |
55 | |
56 | static const char *DISKAUD_GetOutputFilename(void) |
57 | { |
58 | const char *envr = SDL_getenv(DISKENVR_OUTFILE); |
59 | return((envr != NULL) ? envr : DISKDEFAULT_OUTFILE); |
60 | } |
61 | |
62 | /* Audio driver bootstrap functions */ |
63 | static int DISKAUD_Available(void) |
64 | { |
65 | const char *envr = SDL_getenv("SDL_AUDIODRIVER"); |
66 | if (envr && (SDL_strcmp(envr, DISKAUD_DRIVER_NAME) == 0)) { |
67 | return(1); |
68 | } |
69 | return(0); |
70 | } |
71 | |
72 | static void DISKAUD_DeleteDevice(SDL_AudioDevice *device) |
73 | { |
74 | SDL_free(device->hidden); |
75 | SDL_free(device); |
76 | } |
77 | |
78 | static SDL_AudioDevice *DISKAUD_CreateDevice(int devindex) |
79 | { |
80 | SDL_AudioDevice *this; |
81 | const char *envr; |
82 | |
83 | /* Initialize all variables that we clean on shutdown */ |
84 | this = (SDL_AudioDevice *)SDL_malloc(sizeof(SDL_AudioDevice)); |
85 | if ( this ) { |
86 | SDL_memset(this, 0, (sizeof *this)); |
87 | this->hidden = (struct SDL_PrivateAudioData *) |
88 | SDL_malloc((sizeof *this->hidden)); |
89 | } |
90 | if ( (this == NULL) || (this->hidden == NULL) ) { |
91 | SDL_OutOfMemory(); |
92 | if ( this ) { |
93 | SDL_free(this); |
94 | } |
95 | return(0); |
96 | } |
97 | SDL_memset(this->hidden, 0, (sizeof *this->hidden)); |
98 | |
99 | envr = SDL_getenv(DISKENVR_WRITEDELAY); |
100 | this->hidden->write_delay = (envr) ? SDL_atoi(envr) : DISKDEFAULT_WRITEDELAY; |
101 | |
102 | /* Set the function pointers */ |
103 | this->OpenAudio = DISKAUD_OpenAudio; |
104 | this->WaitAudio = DISKAUD_WaitAudio; |
105 | this->PlayAudio = DISKAUD_PlayAudio; |
106 | this->GetAudioBuf = DISKAUD_GetAudioBuf; |
107 | this->CloseAudio = DISKAUD_CloseAudio; |
108 | |
109 | this->free = DISKAUD_DeleteDevice; |
110 | |
111 | return this; |
112 | } |
113 | |
114 | AudioBootStrap DISKAUD_bootstrap = { |
115 | DISKAUD_DRIVER_NAME, "direct-to-disk audio", |
116 | DISKAUD_Available, DISKAUD_CreateDevice |
117 | }; |
118 | |
119 | /* This function waits until it is possible to write a full sound buffer */ |
120 | static void DISKAUD_WaitAudio(_THIS) |
121 | { |
122 | SDL_Delay(this->hidden->write_delay); |
123 | } |
124 | |
125 | static void DISKAUD_PlayAudio(_THIS) |
126 | { |
127 | int written; |
128 | |
129 | /* Write the audio data */ |
130 | written = SDL_RWwrite(this->hidden->output, |
131 | this->hidden->mixbuf, 1, |
132 | this->hidden->mixlen); |
133 | |
134 | /* If we couldn't write, assume fatal error for now */ |
135 | if ( (Uint32)written != this->hidden->mixlen ) { |
136 | this->enabled = 0; |
137 | } |
138 | #ifdef DEBUG_AUDIO |
139 | fprintf(stderr, "Wrote %d bytes of audio data\n", written); |
140 | #endif |
141 | } |
142 | |
143 | static Uint8 *DISKAUD_GetAudioBuf(_THIS) |
144 | { |
145 | return(this->hidden->mixbuf); |
146 | } |
147 | |
148 | static void DISKAUD_CloseAudio(_THIS) |
149 | { |
150 | if ( this->hidden->mixbuf != NULL ) { |
151 | SDL_FreeAudioMem(this->hidden->mixbuf); |
152 | this->hidden->mixbuf = NULL; |
153 | } |
154 | if ( this->hidden->output != NULL ) { |
155 | SDL_RWclose(this->hidden->output); |
156 | this->hidden->output = NULL; |
157 | } |
158 | } |
159 | |
160 | static int DISKAUD_OpenAudio(_THIS, SDL_AudioSpec *spec) |
161 | { |
162 | const char *fname = DISKAUD_GetOutputFilename(); |
163 | |
164 | /* Open the audio device */ |
165 | this->hidden->output = SDL_RWFromFile(fname, "wb"); |
166 | if ( this->hidden->output == NULL ) { |
167 | return(-1); |
168 | } |
169 | |
170 | #if HAVE_STDIO_H |
171 | fprintf(stderr, "WARNING: You are using the SDL disk writer" |
172 | " audio driver!\n Writing to file [%s].\n", fname); |
173 | #endif |
174 | |
175 | /* Allocate mixing buffer */ |
176 | this->hidden->mixlen = spec->size; |
177 | this->hidden->mixbuf = (Uint8 *) SDL_AllocAudioMem(this->hidden->mixlen); |
178 | if ( this->hidden->mixbuf == NULL ) { |
179 | return(-1); |
180 | } |
181 | SDL_memset(this->hidden->mixbuf, spec->silence, spec->size); |
182 | |
183 | /* We're ready to rock and roll. :-) */ |
184 | return(0); |
185 | } |
186 | |