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0
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1 /*
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2 AIX support for the SDL - Simple DirectMedia Layer
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3 Copyright (C) 2000 Carsten Griwodz
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4
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5 This library is free software; you can redistribute it and/or
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6 modify it under the terms of the GNU Library General Public
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7 License as published by the Free Software Foundation; either
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8 version 2 of the License, or (at your option) any later version.
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9
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10 This library is distributed in the hope that it will be useful,
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11 but WITHOUT ANY WARRANTY; without even the implied warranty of
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12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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13 Library General Public License for more details.
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14
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15 You should have received a copy of the GNU Library General Public
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16 License along with this library; if not, write to the Free
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17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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18
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19 Carsten Griwodz
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20 griff@kom.tu-darmstadt.de
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21
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22 based on linux/SDL_dspaudio.c by Sam Lantinga
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23 */
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24
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25 #ifdef SAVE_RCSID
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26 static char rcsid =
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27 "@(#) $Id$";
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28 #endif
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29
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30 /* Allow access to a raw mixing buffer */
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31
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32 #include <stdlib.h>
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33 #include <stdio.h>
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34 #include <string.h>
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35 #include <errno.h>
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36 #include <unistd.h>
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37 #include <fcntl.h>
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38 #include <sys/time.h>
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39 #include <sys/ioctl.h>
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40 #include <sys/stat.h>
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41
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42 #include "SDL_audio.h"
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43 #include "SDL_error.h"
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44 #include "SDL_audiomem.h"
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45 #include "SDL_audio_c.h"
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46 #include "SDL_timer.h"
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47 #include "SDL_audiodev_c.h"
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48 #include "SDL_paudio.h"
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49
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50 #define DEBUG_AUDIO 1
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51
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52 /* A conflict within AIX 4.3.3 <sys/> headers and probably others as well.
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53 * I guess nobody ever uses audio... Shame over AIX header files. */
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54 #include <sys/machine.h>
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55 #undef BIG_ENDIAN
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56 #include <sys/audio.h>
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57
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58 /* The tag name used by paud audio */
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59 #define Paud_DRIVER_NAME "paud"
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60
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61 /* Open the audio device for playback, and don't block if busy */
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62 /* #define OPEN_FLAGS (O_WRONLY|O_NONBLOCK) */
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63 #define OPEN_FLAGS O_WRONLY
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64
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65 /* Audio driver functions */
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66 static int Paud_OpenAudio(_THIS, SDL_AudioSpec *spec);
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67 static void Paud_WaitAudio(_THIS);
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68 static void Paud_PlayAudio(_THIS);
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69 static Uint8 *Paud_GetAudioBuf(_THIS);
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70 static void Paud_CloseAudio(_THIS);
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71
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72 /* Audio driver bootstrap functions */
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73
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74 static int Audio_Available(void)
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75 {
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76 int fd;
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77 int available;
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78
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79 available = 0;
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80 fd = SDL_OpenAudioPath(NULL, 0, OPEN_FLAGS, 0);
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81 if ( fd >= 0 ) {
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82 available = 1;
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83 close(fd);
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84 }
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85 return(available);
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86 }
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87
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88 static void Audio_DeleteDevice(SDL_AudioDevice *device)
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89 {
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90 free(device->hidden);
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91 free(device);
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92 }
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93
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94 static SDL_AudioDevice *Audio_CreateDevice(int devindex)
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95 {
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96 SDL_AudioDevice *this;
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97
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98 /* Initialize all variables that we clean on shutdown */
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99 this = (SDL_AudioDevice *)malloc(sizeof(SDL_AudioDevice));
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100 if ( this ) {
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101 memset(this, 0, (sizeof *this));
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102 this->hidden = (struct SDL_PrivateAudioData *)
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103 malloc((sizeof *this->hidden));
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104 }
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105 if ( (this == NULL) || (this->hidden == NULL) ) {
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106 SDL_OutOfMemory();
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107 if ( this ) {
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108 free(this);
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109 }
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110 return(0);
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111 }
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112 memset(this->hidden, 0, (sizeof *this->hidden));
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113 audio_fd = -1;
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114
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115 /* Set the function pointers */
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116 this->OpenAudio = Paud_OpenAudio;
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117 this->WaitAudio = Paud_WaitAudio;
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118 this->PlayAudio = Paud_PlayAudio;
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119 this->GetAudioBuf = Paud_GetAudioBuf;
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120 this->CloseAudio = Paud_CloseAudio;
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121
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122 this->free = Audio_DeleteDevice;
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123
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124 return this;
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125 }
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126
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127 AudioBootStrap Paud_bootstrap = {
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128 Paud_DRIVER_NAME, "AIX Paudio",
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129 Audio_Available, Audio_CreateDevice
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130 };
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131
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132 /* This function waits until it is possible to write a full sound buffer */
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133 static void Paud_WaitAudio(_THIS)
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134 {
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135 fd_set fdset;
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136
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137 /* See if we need to use timed audio synchronization */
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138 if ( frame_ticks ) {
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139 /* Use timer for general audio synchronization */
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140 Sint32 ticks;
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141
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142 ticks = ((Sint32)(next_frame - SDL_GetTicks()))-FUDGE_TICKS;
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143 if ( ticks > 0 ) {
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144 SDL_Delay(ticks);
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145 }
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146 } else {
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147 audio_buffer paud_bufinfo;
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148
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149 /* Use select() for audio synchronization */
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150 struct timeval timeout;
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151 FD_ZERO(&fdset);
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152 FD_SET(audio_fd, &fdset);
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153
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154 if ( ioctl(audio_fd, AUDIO_BUFFER, &paud_bufinfo) < 0 ) {
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155 #ifdef DEBUG_AUDIO
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156 fprintf(stderr, "Couldn't get audio buffer information\n");
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157 #endif
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158 timeout.tv_sec = 10;
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159 timeout.tv_usec = 0;
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160 } else {
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161 long ms_in_buf = paud_bufinfo.write_buf_time;
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162 timeout.tv_sec = ms_in_buf/1000;
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163 ms_in_buf = ms_in_buf - timeout.tv_sec*1000;
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164 timeout.tv_usec = ms_in_buf*1000;
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165 #ifdef DEBUG_AUDIO
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166 fprintf( stderr,
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167 "Waiting for write_buf_time=%ld,%ld\n",
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168 timeout.tv_sec,
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169 timeout.tv_usec );
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170 #endif
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171 }
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172
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173 #ifdef DEBUG_AUDIO
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174 fprintf(stderr, "Waiting for audio to get ready\n");
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175 #endif
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176 if ( select(audio_fd+1, NULL, &fdset, NULL, &timeout) <= 0 ) {
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177 const char *message = "Audio timeout - buggy audio driver? (disabled)";
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178 /*
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179 * In general we should never print to the screen,
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180 * but in this case we have no other way of letting
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181 * the user know what happened.
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182 */
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183 fprintf(stderr, "SDL: %s - %s\n", strerror(errno), message);
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184 this->enabled = 0;
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185 /* Don't try to close - may hang */
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186 audio_fd = -1;
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187 #ifdef DEBUG_AUDIO
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188 fprintf(stderr, "Done disabling audio\n");
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189 #endif
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190 }
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191 #ifdef DEBUG_AUDIO
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192 fprintf(stderr, "Ready!\n");
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193 #endif
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194 }
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195 }
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196
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197 static void Paud_PlayAudio(_THIS)
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198 {
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199 int written;
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200
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201 /* Write the audio data, checking for EAGAIN on broken audio drivers */
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202 do {
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203 written = write(audio_fd, mixbuf, mixlen);
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204 if ( (written < 0) && ((errno == 0) || (errno == EAGAIN)) ) {
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205 SDL_Delay(1); /* Let a little CPU time go by */
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206 }
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207 } while ( (written < 0) &&
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208 ((errno == 0) || (errno == EAGAIN) || (errno == EINTR)) );
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209
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210 /* If timer synchronization is enabled, set the next write frame */
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211 if ( frame_ticks ) {
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212 next_frame += frame_ticks;
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213 }
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214
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215 /* If we couldn't write, assume fatal error for now */
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216 if ( written < 0 ) {
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217 this->enabled = 0;
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218 }
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219 #ifdef DEBUG_AUDIO
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220 fprintf(stderr, "Wrote %d bytes of audio data\n", written);
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221 #endif
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222 }
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223
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224 static Uint8 *Paud_GetAudioBuf(_THIS)
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225 {
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226 return mixbuf;
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227 }
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228
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229 static void Paud_CloseAudio(_THIS)
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230 {
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231 if ( mixbuf != NULL ) {
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232 SDL_FreeAudioMem(mixbuf);
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233 mixbuf = NULL;
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234 }
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235 if ( audio_fd >= 0 ) {
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236 close(audio_fd);
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237 audio_fd = -1;
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238 }
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239 }
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240
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241 static int Paud_OpenAudio(_THIS, SDL_AudioSpec *spec)
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242 {
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243 char audiodev[1024];
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244 int format;
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245 int bytes_per_sample;
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246 Uint16 test_format;
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247 audio_init paud_init;
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248 audio_buffer paud_bufinfo;
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249 audio_status paud_status;
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250 audio_control paud_control;
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251 audio_change paud_change;
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252
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253 /* Reset the timer synchronization flag */
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254 frame_ticks = 0.0;
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255
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256 /* Open the audio device */
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257 audio_fd = SDL_OpenAudioPath(audiodev, sizeof(audiodev), OPEN_FLAGS, 0);
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258 if ( audio_fd < 0 ) {
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259 SDL_SetError("Couldn't open %s: %s", audiodev, strerror(errno));
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260 return -1;
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261 }
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262
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263 /*
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264 * We can't set the buffer size - just ask the device for the maximum
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265 * that we can have.
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266 */
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267 if ( ioctl(audio_fd, AUDIO_BUFFER, &paud_bufinfo) < 0 ) {
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268 SDL_SetError("Couldn't get audio buffer information");
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269 return -1;
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270 }
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271
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272 mixbuf = NULL;
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273
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274 if ( spec->channels > 1 )
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275 spec->channels = 2;
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276 else
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277 spec->channels = 1;
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278
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279 /*
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280 * Fields in the audio_init structure:
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281 *
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282 * Ignored by us:
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283 *
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284 * paud.loadpath[LOAD_PATH]; * DSP code to load, MWave chip only?
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285 * paud.slot_number; * slot number of the adapter
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286 * paud.device_id; * adapter identification number
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287 *
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288 * Input:
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289 *
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290 * paud.srate; * the sampling rate in Hz
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291 * paud.bits_per_sample; * 8, 16, 32, ...
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292 * paud.bsize; * block size for this rate
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293 * paud.mode; * ADPCM, PCM, MU_LAW, A_LAW, SOURCE_MIX
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294 * paud.channels; * 1=mono, 2=stereo
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295 * paud.flags; * FIXED - fixed length data
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296 * * LEFT_ALIGNED, RIGHT_ALIGNED (var len only)
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297 * * TWOS_COMPLEMENT - 2's complement data
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298 * * SIGNED - signed? comment seems wrong in sys/audio.h
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299 * * BIG_ENDIAN
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300 * paud.operation; * PLAY, RECORD
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301 *
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302 * Output:
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303 *
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304 * paud.flags; * PITCH - pitch is supported
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305 * * INPUT - input is supported
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306 * * OUTPUT - output is supported
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307 * * MONITOR - monitor is supported
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308 * * VOLUME - volume is supported
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309 * * VOLUME_DELAY - volume delay is supported
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310 * * BALANCE - balance is supported
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311 * * BALANCE_DELAY - balance delay is supported
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312 * * TREBLE - treble control is supported
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313 * * BASS - bass control is supported
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314 * * BESTFIT_PROVIDED - best fit returned
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315 * * LOAD_CODE - DSP load needed
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316 * paud.rc; * NO_PLAY - DSP code can't do play requests
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317 * * NO_RECORD - DSP code can't do record requests
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318 * * INVALID_REQUEST - request was invalid
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319 * * CONFLICT - conflict with open's flags
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320 * * OVERLOADED - out of DSP MIPS or memory
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321 * paud.position_resolution; * smallest increment for position
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322 */
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323
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324 paud_init.srate = spec->freq;
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325 paud_init.mode = PCM;
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326 paud_init.operation = PLAY;
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327 paud_init.channels = spec->channels;
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328
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329 /* Try for a closest match on audio format */
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330 format = 0;
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331 for ( test_format = SDL_FirstAudioFormat(spec->format);
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332 ! format && test_format; ) {
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333 #ifdef DEBUG_AUDIO
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334 fprintf(stderr, "Trying format 0x%4.4x\n", test_format);
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335 #endif
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336 switch ( test_format ) {
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337 case AUDIO_U8:
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338 bytes_per_sample = 1;
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339 paud_init.bits_per_sample = 8;
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340 paud_init.flags = TWOS_COMPLEMENT | FIXED;
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341 format = 1;
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342 break;
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343 case AUDIO_S8:
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344 bytes_per_sample = 1;
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345 paud_init.bits_per_sample = 8;
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346 paud_init.flags = SIGNED |
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347 TWOS_COMPLEMENT | FIXED;
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348 format = 1;
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349 break;
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350 case AUDIO_S16LSB:
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351 bytes_per_sample = 2;
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352 paud_init.bits_per_sample = 16;
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353 paud_init.flags = SIGNED |
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354 TWOS_COMPLEMENT | FIXED;
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355 format = 1;
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356 break;
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357 case AUDIO_S16MSB:
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358 bytes_per_sample = 2;
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359 paud_init.bits_per_sample = 16;
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360 paud_init.flags = BIG_ENDIAN |
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361 SIGNED |
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362 TWOS_COMPLEMENT | FIXED;
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363 format = 1;
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364 break;
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365 case AUDIO_U16LSB:
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366 bytes_per_sample = 2;
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367 paud_init.bits_per_sample = 16;
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368 paud_init.flags = TWOS_COMPLEMENT | FIXED;
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369 format = 1;
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370 break;
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371 case AUDIO_U16MSB:
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372 bytes_per_sample = 2;
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373 paud_init.bits_per_sample = 16;
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374 paud_init.flags = BIG_ENDIAN |
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375 TWOS_COMPLEMENT | FIXED;
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376 format = 1;
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377 break;
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378 default:
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379 break;
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380 }
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381 if ( ! format ) {
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382 test_format = SDL_NextAudioFormat();
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383 }
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384 }
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385 if ( format == 0 ) {
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386 #ifdef DEBUG_AUDIO
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387 fprintf(stderr, "Couldn't find any hardware audio formats\n");
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388 #endif
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389 SDL_SetError("Couldn't find any hardware audio formats");
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390 return -1;
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391 }
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392 spec->format = test_format;
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393
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394 /*
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395 * We know the buffer size and the max number of subsequent writes
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396 * that can be pending. If more than one can pend, allow the application
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397 * to do something like double buffering between our write buffer and
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398 * the device's own buffer that we are filling with write() anyway.
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399 *
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400 * We calculate spec->samples like this because SDL_CalculateAudioSpec()
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401 * will give put paud_bufinfo.write_buf_cap (or paud_bufinfo.write_buf_cap/2)
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402 * into spec->size in return.
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403 */
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404 if ( paud_bufinfo.request_buf_cap == 1 )
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405 {
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406 spec->samples = paud_bufinfo.write_buf_cap
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407 / bytes_per_sample
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408 / spec->channels;
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409 }
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410 else
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411 {
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412 spec->samples = paud_bufinfo.write_buf_cap
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413 / bytes_per_sample
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414 / spec->channels
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415 / 2;
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416 }
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417 paud_init.bsize = bytes_per_sample * spec->channels;
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418
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419 SDL_CalculateAudioSpec(spec);
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420
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421 /*
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422 * The AIX paud device init can't modify the values of the audio_init
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423 * structure that we pass to it. So we don't need any recalculation
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424 * of this stuff and no reinit call as in linux dsp and dma code.
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425 *
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426 * /dev/paud supports all of the encoding formats, so we don't need
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427 * to do anything like reopening the device, either.
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428 */
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429 if ( ioctl(audio_fd, AUDIO_INIT, &paud_init) < 0 ) {
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430 switch ( paud_init.rc )
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431 {
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432 case 1 :
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433 SDL_SetError("Couldn't set audio format: DSP can't do play requests");
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434 return -1;
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435 break;
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436 case 2 :
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437 SDL_SetError("Couldn't set audio format: DSP can't do record requests");
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438 return -1;
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439 break;
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440 case 4 :
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441 SDL_SetError("Couldn't set audio format: request was invalid");
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442 return -1;
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443 break;
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444 case 5 :
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445 SDL_SetError("Couldn't set audio format: conflict with open's flags");
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446 return -1;
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447 break;
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448 case 6 :
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449 SDL_SetError("Couldn't set audio format: out of DSP MIPS or memory");
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450 return -1;
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451 break;
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452 default :
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453 SDL_SetError("Couldn't set audio format: not documented in sys/audio.h");
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454 return -1;
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455 break;
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456 }
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457 }
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458
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459 /* Allocate mixing buffer */
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460 mixlen = spec->size;
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461 mixbuf = (Uint8 *)SDL_AllocAudioMem(mixlen);
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462 if ( mixbuf == NULL ) {
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463 return -1;
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464 }
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465 memset(mixbuf, spec->silence, spec->size);
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466
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467 /*
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468 * Set some paramters: full volume, first speaker that we can find.
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469 * Ignore the other settings for now.
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470 */
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471 paud_change.input = AUDIO_IGNORE; /* the new input source */
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472 paud_change.output = OUTPUT_1; /* EXTERNAL_SPEAKER,INTERNAL_SPEAKER,OUTPUT_1 */
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473 paud_change.monitor = AUDIO_IGNORE; /* the new monitor state */
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474 paud_change.volume = 0x7fffffff; /* volume level [0-0x7fffffff] */
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475 paud_change.volume_delay = AUDIO_IGNORE; /* the new volume delay */
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476 paud_change.balance = 0x3fffffff; /* the new balance */
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477 paud_change.balance_delay = AUDIO_IGNORE; /* the new balance delay */
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478 paud_change.treble = AUDIO_IGNORE; /* the new treble state */
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479 paud_change.bass = AUDIO_IGNORE; /* the new bass state */
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480 paud_change.pitch = AUDIO_IGNORE; /* the new pitch state */
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481
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482 paud_control.ioctl_request = AUDIO_CHANGE;
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483 paud_control.request_info = (char*)&paud_change;
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484 if ( ioctl(audio_fd, AUDIO_CONTROL, &paud_control) < 0 ) {
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485 #ifdef DEBUG_AUDIO
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486 fprintf(stderr, "Can't change audio display settings\n" );
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487 #endif
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488 }
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489
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490 /*
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491 * Tell the device to expect data. Actual start will wait for
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492 * the first write() call.
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493 */
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494 paud_control.ioctl_request = AUDIO_START;
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495 paud_control.position = 0;
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496 if ( ioctl(audio_fd, AUDIO_CONTROL, &paud_control) < 0 ) {
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497 #ifdef DEBUG_AUDIO
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498 fprintf(stderr, "Can't start audio play\n" );
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499 #endif
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500 SDL_SetError("Can't start audio play");
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501 return -1;
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502 }
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503
|
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504 /* Check to see if we need to use select() workaround */
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|
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505 { char *workaround;
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506 workaround = getenv("SDL_DSP_NOSELECT");
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|
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507 if ( workaround ) {
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508 frame_ticks = (float)(spec->samples*1000)/spec->freq;
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509 next_frame = SDL_GetTicks()+frame_ticks;
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510 }
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511 }
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512
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513 /* Get the parent process id (we're the parent of the audio thread) */
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514 parent = getpid();
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515
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516 /* We're ready to rock and roll. :-) */
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|
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517 return 0;
|
|
|
518 }
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519
|
