This repository has been archived by the owner on Feb 11, 2021. It is now read-only.
SDL_diskaudio.c
1
2
/*
Simple DirectMedia Layer
3
Copyright (C) 1997-2013 Sam Lantinga <slouken@libsdl.org>
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/
#include "SDL_config.h"
#if SDL_AUDIO_DRIVER_DISK
/* Output raw audio data to a file. */
#if HAVE_STDIO_H
#include <stdio.h>
#endif
#include "SDL_rwops.h"
#include "SDL_timer.h"
#include "SDL_audio.h"
#include "../SDL_audiomem.h"
#include "../SDL_audio_c.h"
#include "SDL_diskaudio.h"
/* environment variables and defaults. */
#define DISKENVR_OUTFILE "SDL_DISKAUDIOFILE"
#define DISKDEFAULT_OUTFILE "sdlaudio.raw"
#define DISKENVR_WRITEDELAY "SDL_DISKAUDIODELAY"
#define DISKDEFAULT_WRITEDELAY 150
static const char *
DISKAUD_GetOutputFilename(const char *devname)
{
if (devname == NULL) {
devname = SDL_getenv(DISKENVR_OUTFILE);
if (devname == NULL) {
devname = DISKDEFAULT_OUTFILE;
}
}
return devname;
}
/* This function waits until it is possible to write a full sound buffer */
static void
DISKAUD_WaitDevice(_THIS)
{
SDL_Delay(this->hidden->write_delay);
}
static void
DISKAUD_PlayDevice(_THIS)
{
size_t written;
/* Write the audio data */
written = SDL_RWwrite(this->hidden->output,
this->hidden->mixbuf, 1, this->hidden->mixlen);
/* If we couldn't write, assume fatal error for now */
if (written != this->hidden->mixlen) {
this->enabled = 0;
}
#ifdef DEBUG_AUDIO
fprintf(stderr, "Wrote %d bytes of audio data\n", written);
#endif
}
static Uint8 *
DISKAUD_GetDeviceBuf(_THIS)
{
return (this->hidden->mixbuf);
}
static void
DISKAUD_CloseDevice(_THIS)
{
if (this->hidden != NULL) {
if (this->hidden->mixbuf != NULL) {
SDL_FreeAudioMem(this->hidden->mixbuf);
this->hidden->mixbuf = NULL;
}
if (this->hidden->output != NULL) {
SDL_RWclose(this->hidden->output);
this->hidden->output = NULL;
}
SDL_free(this->hidden);
this->hidden = NULL;
}
}
static int
DISKAUD_OpenDevice(_THIS, const char *devname, int iscapture)
{
const char *envr = SDL_getenv(DISKENVR_WRITEDELAY);
const char *fname = DISKAUD_GetOutputFilename(devname);
this->hidden = (struct SDL_PrivateAudioData *)
SDL_malloc(sizeof(*this->hidden));
if (this->hidden == NULL) {
113
return SDL_OutOfMemory();
114
115
116
}
SDL_memset(this->hidden, 0, sizeof(*this->hidden));
117
118
119
120
this->hidden->mixlen = this->spec.size;
this->hidden->write_delay =
(envr) ? SDL_atoi(envr) : DISKDEFAULT_WRITEDELAY;
121
122
123
124
/* Open the audio device */
this->hidden->output = SDL_RWFromFile(fname, "wb");
if (this->hidden->output == NULL) {
DISKAUD_CloseDevice(this);
126
127
128
129
130
131
}
/* Allocate mixing buffer */
this->hidden->mixbuf = (Uint8 *) SDL_AllocAudioMem(this->hidden->mixlen);
if (this->hidden->mixbuf == NULL) {
DISKAUD_CloseDevice(this);
133
134
135
136
137
138
139
140
141
142
}
SDL_memset(this->hidden->mixbuf, this->spec.silence, this->spec.size);
#if HAVE_STDIO_H
fprintf(stderr,
"WARNING: You are using the SDL disk writer audio driver!\n"
" Writing to file [%s].\n", fname);
#endif
/* We're ready to rock and roll. :-) */
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
}
static int
DISKAUD_Init(SDL_AudioDriverImpl * impl)
{
/* Set the function pointers */
impl->OpenDevice = DISKAUD_OpenDevice;
impl->WaitDevice = DISKAUD_WaitDevice;
impl->PlayDevice = DISKAUD_PlayDevice;
impl->GetDeviceBuf = DISKAUD_GetDeviceBuf;
impl->CloseDevice = DISKAUD_CloseDevice;
return 1; /* this audio target is available. */
}
AudioBootStrap DISKAUD_bootstrap = {
"disk", "direct-to-disk audio", DISKAUD_Init, 1
};
#endif /* SDL_AUDIO_DRIVER_DISK */
/* vi: set ts=4 sw=4 expandtab: */