src/audio/esd/SDL_esdaudio.c
author Ryan C. Gordon
Fri, 05 Aug 2016 01:44:41 -0400
changeset 10255 9530fc07da6c
parent 9998 f67cf37e9cd4
child 10256 620329de23d4
permissions -rw-r--r--
audio: Clean up some CloseDevice() interface details.

- It's now always called if device->hidden isn't NULL, even if OpenDevice()
failed halfway through. This lets implementation code not have to clean up
itself on every possible failure point; just return an error and SDL will
handle it for you.

- Implementations can assume this->hidden != NULL and not check for it.

- implementations don't have to set this->hidden = NULL when done, because
the caller is always about to free(this).

- Don't reset other fields that are in a block of memory about to be free()'d.

- Implementations all now free things like internal mix buffers last, after
closing devices and such, to guarantee they definitely aren't in use anymore
at the point of deallocation.
slouken@0
     1
/*
slouken@5535
     2
  Simple DirectMedia Layer
slouken@9998
     3
  Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
slouken@0
     4
slouken@5535
     5
  This software is provided 'as-is', without any express or implied
slouken@5535
     6
  warranty.  In no event will the authors be held liable for any damages
slouken@5535
     7
  arising from the use of this software.
slouken@0
     8
slouken@5535
     9
  Permission is granted to anyone to use this software for any purpose,
slouken@5535
    10
  including commercial applications, and to alter it and redistribute it
slouken@5535
    11
  freely, subject to the following restrictions:
slouken@0
    12
slouken@5535
    13
  1. The origin of this software must not be misrepresented; you must not
slouken@5535
    14
     claim that you wrote the original software. If you use this software
slouken@5535
    15
     in a product, an acknowledgment in the product documentation would be
slouken@5535
    16
     appreciated but is not required.
slouken@5535
    17
  2. Altered source versions must be plainly marked as such, and must not be
slouken@5535
    18
     misrepresented as being the original software.
slouken@5535
    19
  3. This notice may not be removed or altered from any source distribution.
slouken@0
    20
*/
icculus@8093
    21
#include "../../SDL_internal.h"
slouken@0
    22
slouken@6044
    23
#if SDL_AUDIO_DRIVER_ESD
slouken@6044
    24
slouken@0
    25
/* Allow access to an ESD network stream mixing buffer */
slouken@0
    26
slouken@1616
    27
#include <sys/types.h>
slouken@1616
    28
#include <unistd.h>
slouken@1616
    29
#include <signal.h>
slouken@0
    30
#include <errno.h>
slouken@0
    31
#include <esd.h>
slouken@0
    32
slouken@1358
    33
#include "SDL_timer.h"
slouken@0
    34
#include "SDL_audio.h"
slouken@1361
    35
#include "../SDL_audiomem.h"
slouken@1361
    36
#include "../SDL_audio_c.h"
slouken@0
    37
#include "SDL_esdaudio.h"
slouken@0
    38
icculus@6046
    39
#ifdef SDL_AUDIO_DRIVER_ESD_DYNAMIC
slouken@294
    40
#include "SDL_name.h"
slouken@294
    41
#include "SDL_loadso.h"
slouken@294
    42
#else
slouken@7191
    43
#define SDL_NAME(X) X
slouken@294
    44
#endif
slouken@294
    45
icculus@6046
    46
#ifdef SDL_AUDIO_DRIVER_ESD_DYNAMIC
slouken@294
    47
slouken@1361
    48
static const char *esd_library = SDL_AUDIO_DRIVER_ESD_DYNAMIC;
slouken@294
    49
static void *esd_handle = NULL;
slouken@294
    50
slouken@1895
    51
static int (*SDL_NAME(esd_open_sound)) (const char *host);
slouken@1895
    52
static int (*SDL_NAME(esd_close)) (int esd);
slouken@1895
    53
static int (*SDL_NAME(esd_play_stream)) (esd_format_t format, int rate,
slouken@1895
    54
                                         const char *host, const char *name);
icculus@2049
    55
icculus@2049
    56
#define SDL_ESD_SYM(x) { #x, (void **) (char *) &SDL_NAME(x) }
slouken@1895
    57
static struct
slouken@1895
    58
{
slouken@1895
    59
    const char *name;
slouken@1895
    60
    void **func;
slouken@3162
    61
} const esd_functions[] = {
slouken@3162
    62
    SDL_ESD_SYM(esd_open_sound),
slouken@3162
    63
    SDL_ESD_SYM(esd_close), SDL_ESD_SYM(esd_play_stream),
slouken@3162
    64
};
slouken@3162
    65
icculus@2049
    66
#undef SDL_ESD_SYM
slouken@294
    67
slouken@1895
    68
static void
slouken@1895
    69
UnloadESDLibrary()
slouken@294
    70
{
icculus@2049
    71
    if (esd_handle != NULL) {
slouken@1895
    72
        SDL_UnloadObject(esd_handle);
slouken@1895
    73
        esd_handle = NULL;
slouken@1895
    74
    }
slouken@294
    75
}
slouken@294
    76
slouken@1895
    77
static int
slouken@1895
    78
LoadESDLibrary(void)
slouken@294
    79
{
slouken@1895
    80
    int i, retval = -1;
slouken@294
    81
icculus@2049
    82
    if (esd_handle == NULL) {
icculus@2049
    83
        esd_handle = SDL_LoadObject(esd_library);
icculus@2049
    84
        if (esd_handle) {
icculus@2049
    85
            retval = 0;
icculus@2049
    86
            for (i = 0; i < SDL_arraysize(esd_functions); ++i) {
icculus@2049
    87
                *esd_functions[i].func =
icculus@2049
    88
                    SDL_LoadFunction(esd_handle, esd_functions[i].name);
icculus@2049
    89
                if (!*esd_functions[i].func) {
icculus@2049
    90
                    retval = -1;
icculus@2049
    91
                    UnloadESDLibrary();
icculus@2049
    92
                    break;
icculus@2049
    93
                }
slouken@1895
    94
            }
slouken@1895
    95
        }
slouken@1895
    96
    }
slouken@1895
    97
    return retval;
slouken@294
    98
}
slouken@294
    99
slouken@294
   100
#else
slouken@294
   101
slouken@1895
   102
static void
slouken@1895
   103
UnloadESDLibrary()
slouken@294
   104
{
slouken@1895
   105
    return;
slouken@294
   106
}
slouken@294
   107
slouken@1895
   108
static int
slouken@1895
   109
LoadESDLibrary(void)
slouken@294
   110
{
slouken@1895
   111
    return 0;
slouken@294
   112
}
slouken@294
   113
slouken@1361
   114
#endif /* SDL_AUDIO_DRIVER_ESD_DYNAMIC */
slouken@294
   115
slouken@0
   116
slouken@0
   117
/* This function waits until it is possible to write a full sound buffer */
slouken@1895
   118
static void
icculus@2049
   119
ESD_WaitDevice(_THIS)
slouken@0
   120
{
slouken@1895
   121
    Sint32 ticks;
slouken@0
   122
slouken@1895
   123
    /* Check to see if the thread-parent process is still alive */
slouken@1895
   124
    {
slouken@1895
   125
        static int cnt = 0;
slouken@7191
   126
        /* Note that this only works with thread implementations
slouken@1895
   127
           that use a different process id for each thread.
slouken@1895
   128
         */
icculus@2049
   129
        /* Check every 10 loops */
icculus@2049
   130
        if (this->hidden->parent && (((++cnt) % 10) == 0)) {
slouken@3068
   131
            if (kill(this->hidden->parent, 0) < 0 && errno == ESRCH) {
icculus@9394
   132
                SDL_OpenedAudioDeviceDisconnected(this);
slouken@1895
   133
            }
slouken@1895
   134
        }
slouken@1895
   135
    }
slouken@0
   136
slouken@1895
   137
    /* Use timer for general audio synchronization */
slouken@7857
   138
    ticks = ((Sint32) (this->hidden->next_frame - SDL_GetTicks())) - FUDGE_TICKS;
slouken@1895
   139
    if (ticks > 0) {
slouken@1895
   140
        SDL_Delay(ticks);
slouken@1895
   141
    }
slouken@0
   142
}
slouken@0
   143
slouken@1895
   144
static void
icculus@2049
   145
ESD_PlayDevice(_THIS)
slouken@0
   146
{
icculus@2049
   147
    int written = 0;
slouken@0
   148
slouken@1895
   149
    /* Write the audio data, checking for EAGAIN on broken audio drivers */
slouken@1895
   150
    do {
icculus@2049
   151
        written = write(this->hidden->audio_fd,
slouken@2060
   152
                        this->hidden->mixbuf, this->hidden->mixlen);
slouken@1895
   153
        if ((written < 0) && ((errno == 0) || (errno == EAGAIN))) {
slouken@1895
   154
            SDL_Delay(1);       /* Let a little CPU time go by */
slouken@1895
   155
        }
slouken@2735
   156
    } while ((written < 0) &&
slouken@2735
   157
             ((errno == 0) || (errno == EAGAIN) || (errno == EINTR)));
slouken@0
   158
slouken@1895
   159
    /* Set the next write frame */
icculus@2049
   160
    this->hidden->next_frame += this->hidden->frame_ticks;
slouken@0
   161
slouken@1895
   162
    /* If we couldn't write, assume fatal error for now */
slouken@1895
   163
    if (written < 0) {
icculus@9394
   164
        SDL_OpenedAudioDeviceDisconnected(this);
slouken@1895
   165
    }
slouken@0
   166
}
slouken@0
   167
slouken@1895
   168
static Uint8 *
icculus@2049
   169
ESD_GetDeviceBuf(_THIS)
slouken@0
   170
{
icculus@2049
   171
    return (this->hidden->mixbuf);
slouken@0
   172
}
slouken@0
   173
slouken@1895
   174
static void
icculus@2049
   175
ESD_CloseDevice(_THIS)
slouken@0
   176
{
icculus@10255
   177
    if (this->hidden->audio_fd >= 0) {
icculus@10255
   178
        SDL_NAME(esd_close) (this->hidden->audio_fd);
slouken@1895
   179
    }
icculus@10255
   180
    SDL_FreeAudioMem(this->hidden->mixbuf);
icculus@10255
   181
    SDL_free(this->hidden);
slouken@0
   182
}
slouken@0
   183
slouken@0
   184
/* Try to get the name of the program */
slouken@1895
   185
static char *
slouken@1895
   186
get_progname(void)
slouken@0
   187
{
slouken@1895
   188
    char *progname = NULL;
slouken@1402
   189
#ifdef __LINUX__
slouken@1895
   190
    FILE *fp;
slouken@1895
   191
    static char temp[BUFSIZ];
slouken@0
   192
slouken@1895
   193
    SDL_snprintf(temp, SDL_arraysize(temp), "/proc/%d/cmdline", getpid());
slouken@1895
   194
    fp = fopen(temp, "r");
slouken@1895
   195
    if (fp != NULL) {
slouken@1895
   196
        if (fgets(temp, sizeof(temp) - 1, fp)) {
slouken@1895
   197
            progname = SDL_strrchr(temp, '/');
slouken@1895
   198
            if (progname == NULL) {
slouken@1895
   199
                progname = temp;
slouken@1895
   200
            } else {
slouken@1895
   201
                progname = progname + 1;
slouken@1895
   202
            }
slouken@1895
   203
        }
slouken@1895
   204
        fclose(fp);
slouken@1895
   205
    }
slouken@0
   206
#endif
slouken@1895
   207
    return (progname);
slouken@0
   208
}
slouken@0
   209
icculus@2049
   210
slouken@1895
   211
static int
icculus@9394
   212
ESD_OpenDevice(_THIS, void *handle, const char *devname, int iscapture)
slouken@0
   213
{
icculus@2049
   214
    esd_format_t format = (ESD_STREAM | ESD_PLAY);
icculus@2049
   215
    SDL_AudioFormat test_format = 0;
icculus@2049
   216
    int found = 0;
icculus@2049
   217
icculus@2049
   218
    /* Initialize all variables that we clean on shutdown */
icculus@2049
   219
    this->hidden = (struct SDL_PrivateAudioData *)
slouken@2060
   220
        SDL_malloc((sizeof *this->hidden));
icculus@2049
   221
    if (this->hidden == NULL) {
icculus@7038
   222
        return SDL_OutOfMemory();
icculus@2049
   223
    }
icculus@2049
   224
    SDL_memset(this->hidden, 0, (sizeof *this->hidden));
icculus@2049
   225
    this->hidden->audio_fd = -1;
slouken@0
   226
slouken@1895
   227
    /* Convert audio spec to the ESD audio format */
icculus@2049
   228
    /* Try for a closest match on audio format */
icculus@2049
   229
    for (test_format = SDL_FirstAudioFormat(this->spec.format);
icculus@2049
   230
         !found && test_format; test_format = SDL_NextAudioFormat()) {
icculus@2049
   231
#ifdef DEBUG_AUDIO
icculus@2049
   232
        fprintf(stderr, "Trying format 0x%4.4x\n", test_format);
icculus@2049
   233
#endif
icculus@2049
   234
        found = 1;
icculus@2049
   235
        switch (test_format) {
slouken@2060
   236
        case AUDIO_U8:
slouken@2060
   237
            format |= ESD_BITS8;
slouken@2060
   238
            break;
slouken@2060
   239
        case AUDIO_S16SYS:
slouken@2060
   240
            format |= ESD_BITS16;
slouken@2060
   241
            break;
slouken@2060
   242
        default:
slouken@2060
   243
            found = 0;
slouken@2060
   244
            break;
icculus@2049
   245
        }
slouken@1895
   246
    }
icculus@2049
   247
icculus@2049
   248
    if (!found) {
icculus@7038
   249
        return SDL_SetError("Couldn't find any hardware audio formats");
icculus@2049
   250
    }
icculus@2049
   251
icculus@2049
   252
    if (this->spec.channels == 1) {
slouken@1895
   253
        format |= ESD_MONO;
slouken@1895
   254
    } else {
slouken@1895
   255
        format |= ESD_STEREO;
slouken@1895
   256
    }
slouken@0
   257
#if 0
slouken@2060
   258
    this->spec.samples = ESD_BUF_SIZE;  /* Darn, no way to change this yet */
slouken@0
   259
#endif
slouken@0
   260
slouken@1895
   261
    /* Open a connection to the ESD audio server */
icculus@2049
   262
    this->hidden->audio_fd =
slouken@2060
   263
        SDL_NAME(esd_play_stream) (format, this->spec.freq, NULL,
slouken@2060
   264
                                   get_progname());
icculus@2049
   265
icculus@2049
   266
    if (this->hidden->audio_fd < 0) {
icculus@7038
   267
        return SDL_SetError("Couldn't open ESD connection");
slouken@1895
   268
    }
slouken@0
   269
slouken@1895
   270
    /* Calculate the final parameters for this audio specification */
icculus@2049
   271
    SDL_CalculateAudioSpec(&this->spec);
slouken@2060
   272
    this->hidden->frame_ticks =
slouken@2060
   273
        (float) (this->spec.samples * 1000) / this->spec.freq;
icculus@2049
   274
    this->hidden->next_frame = SDL_GetTicks() + this->hidden->frame_ticks;
slouken@0
   275
slouken@1895
   276
    /* Allocate mixing buffer */
icculus@2049
   277
    this->hidden->mixlen = this->spec.size;
icculus@2049
   278
    this->hidden->mixbuf = (Uint8 *) SDL_AllocAudioMem(this->hidden->mixlen);
icculus@2049
   279
    if (this->hidden->mixbuf == NULL) {
icculus@7038
   280
        return SDL_OutOfMemory();
slouken@1895
   281
    }
icculus@2049
   282
    SDL_memset(this->hidden->mixbuf, this->spec.silence, this->spec.size);
slouken@0
   283
slouken@1895
   284
    /* Get the parent process id (we're the parent of the audio thread) */
icculus@2049
   285
    this->hidden->parent = getpid();
slouken@0
   286
slouken@1895
   287
    /* We're ready to rock and roll. :-) */
icculus@7038
   288
    return 0;
icculus@2049
   289
}
icculus@2049
   290
icculus@2049
   291
static void
icculus@2049
   292
ESD_Deinitialize(void)
icculus@2049
   293
{
icculus@2049
   294
    UnloadESDLibrary();
slouken@0
   295
}
slouken@1895
   296
icculus@2049
   297
static int
slouken@2060
   298
ESD_Init(SDL_AudioDriverImpl * impl)
icculus@2049
   299
{
icculus@2049
   300
    if (LoadESDLibrary() < 0) {
icculus@2049
   301
        return 0;
icculus@2049
   302
    } else {
icculus@2049
   303
        int connection = 0;
icculus@2049
   304
icculus@2049
   305
        /* Don't start ESD if it's not running */
icculus@3581
   306
        SDL_setenv("ESD_NO_SPAWN", "1", 0);
icculus@2049
   307
icculus@2049
   308
        connection = SDL_NAME(esd_open_sound) (NULL);
icculus@2049
   309
        if (connection < 0) {
icculus@2049
   310
            UnloadESDLibrary();
icculus@2049
   311
            SDL_SetError("ESD: esd_open_sound failed (no audio server?)");
icculus@2049
   312
            return 0;
icculus@2049
   313
        }
icculus@2049
   314
        SDL_NAME(esd_close) (connection);
icculus@2049
   315
    }
icculus@2049
   316
icculus@2049
   317
    /* Set the function pointers */
icculus@2049
   318
    impl->OpenDevice = ESD_OpenDevice;
icculus@2049
   319
    impl->PlayDevice = ESD_PlayDevice;
icculus@2049
   320
    impl->WaitDevice = ESD_WaitDevice;
icculus@2049
   321
    impl->GetDeviceBuf = ESD_GetDeviceBuf;
icculus@2049
   322
    impl->CloseDevice = ESD_CloseDevice;
icculus@2049
   323
    impl->Deinitialize = ESD_Deinitialize;
icculus@2049
   324
    impl->OnlyHasDefaultOutputDevice = 1;
icculus@2049
   325
icculus@3699
   326
    return 1;   /* this audio target is available. */
icculus@2049
   327
}
icculus@2049
   328
icculus@2049
   329
icculus@2049
   330
AudioBootStrap ESD_bootstrap = {
icculus@5594
   331
    "esd", "Enlightened Sound Daemon", ESD_Init, 0
icculus@2049
   332
};
icculus@2049
   333
slouken@6044
   334
#endif /* SDL_AUDIO_DRIVER_ESD */
slouken@6044
   335
slouken@1895
   336
/* vi: set ts=4 sw=4 expandtab: */