1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 #include <dlfcn.h> 17 #include <stdio.h> 18 #include <alsa/asoundlib.h> 19 20 #define D(...) fprintf(stderr,__VA_ARGS__) 21 #define STRINGIFY(x) _STRINGIFY(x) 22 #define _STRINGIFY(x) #x 23 24 #define DYN_SYMBOLS \ 25 DYN_FUNCTION(size_t,snd_pcm_sw_params_sizeof,(void)) \ 26 DYN_FUNCTION(int,snd_pcm_hw_params_current,(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)) \ 27 DYN_FUNCTION(int,snd_pcm_sw_params_set_start_threshold,(snd_pcm_t *pcm, snd_pcm_sw_params_t *params, snd_pcm_uframes_t val)) \ 28 DYN_FUNCTION(int,snd_pcm_sw_params,(snd_pcm_t *pcm, snd_pcm_sw_params_t *params)) \ 29 DYN_FUNCTION(int,snd_pcm_sw_params_current,(snd_pcm_t *pcm, snd_pcm_sw_params_t *params)) \ 30 DYN_FUNCTION(size_t,snd_pcm_hw_params_sizeof,(void)) \ 31 DYN_FUNCTION(int,snd_pcm_hw_params_any,(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)) \ 32 DYN_FUNCTION(int,snd_pcm_hw_params_set_access,(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_access_t _access)) \ 33 DYN_FUNCTION(int,snd_pcm_hw_params_set_format,(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_format_t val)) \ 34 DYN_FUNCTION(int,snd_pcm_hw_params_set_rate_near,(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir)) \ 35 DYN_FUNCTION(int,snd_pcm_hw_params_set_channels_near,(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val)) \ 36 DYN_FUNCTION(int,snd_pcm_hw_params_set_buffer_time_near,(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir)) \ 37 DYN_FUNCTION(int,snd_pcm_hw_params,(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)) \ 38 DYN_FUNCTION(int,snd_pcm_hw_params_get_buffer_size,(const snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val)) \ 39 DYN_FUNCTION(int,snd_pcm_prepare,(snd_pcm_t *pcm)) \ 40 DYN_FUNCTION(int,snd_pcm_hw_params_get_period_size,(const snd_pcm_hw_params_t *params, snd_pcm_uframes_t *frames, int *dir)) \ 41 DYN_FUNCTION(int,snd_pcm_hw_params_get_period_size_min,(const snd_pcm_hw_params_t *params, snd_pcm_uframes_t *frames, int *dir)) \ 42 DYN_FUNCTION(int,snd_pcm_hw_params_set_period_size,(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t val, int dir)) \ 43 DYN_FUNCTION(int,snd_pcm_hw_params_get_buffer_size_min,(const snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val)) \ 44 DYN_FUNCTION(int,snd_pcm_hw_params_set_buffer_size,(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t val)) \ 45 DYN_FUNCTION(int,snd_pcm_hw_params_set_period_time_near,(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir)) \ 46 DYN_FUNCTION(snd_pcm_sframes_t,snd_pcm_avail_update,(snd_pcm_t *pcm)) \ 47 DYN_FUNCTION(int,snd_pcm_drop,(snd_pcm_t *pcm)) \ 48 DYN_FUNCTION(snd_pcm_sframes_t,snd_pcm_writei,(snd_pcm_t *pcm, const void *buffer, snd_pcm_uframes_t size)) \ 49 DYN_FUNCTION(snd_pcm_sframes_t,snd_pcm_readi,(snd_pcm_t *pcm, void *buffer, snd_pcm_uframes_t size)) \ 50 DYN_FUNCTION(snd_pcm_state_t,snd_pcm_state,(snd_pcm_t *pcm)) \ 51 DYN_FUNCTION(const char*,snd_strerror,(int errnum)) \ 52 DYN_FUNCTION(int,snd_pcm_open,(snd_pcm_t **pcm, const char *name,snd_pcm_stream_t stream, int mode)) \ 53 DYN_FUNCTION(int,snd_pcm_close,(snd_pcm_t *pcm)) \ 54 55 56 57 /* define pointers to library functions we're going to use */ 58 #define DYN_FUNCTION(ret,name,sig) \ 59 static ret (*func_ ## name)sig; 60 61 DYN_SYMBOLS 62 63 #undef DYN_FUNCTION 64 65 #define func_snd_pcm_hw_params_alloca(ptr) \ 66 do { assert(ptr); *ptr = (snd_pcm_hw_params_t *) alloca(func_snd_pcm_hw_params_sizeof()); memset(*ptr, 0, func_snd_pcm_hw_params_sizeof()); } while (0) 67 68 #define func_snd_pcm_sw_params_alloca(ptr) \ 69 do { assert(ptr); *ptr = (snd_pcm_sw_params_t *) alloca(func_snd_pcm_sw_params_sizeof()); memset(*ptr, 0, func_snd_pcm_sw_params_sizeof()); } while (0) 70 71 static void* alsa_lib; 72 73 int main(void) 74 { 75 int result = 1; 76 77 alsa_lib = dlopen( "libasound.so", RTLD_NOW ); 78 if (alsa_lib == NULL) 79 alsa_lib = dlopen( "libasound.so.2", RTLD_NOW ); 80 81 if (alsa_lib == NULL) { 82 D("could not find libasound on this system\n"); 83 return 1; 84 } 85 86 #undef DYN_FUNCTION 87 #define DYN_FUNCTION(ret,name,sig) \ 88 do { \ 89 (func_ ##name) = dlsym( alsa_lib, STRINGIFY(name) ); \ 90 if ((func_##name) == NULL) { \ 91 D("could not find %s in libasound\n", STRINGIFY(name)); \ 92 goto Fail; \ 93 } \ 94 } while (0); 95 96 DYN_SYMBOLS 97 98 result = 0; 99 goto Exit; 100 101 Fail: 102 D("failed to open library\n"); 103 104 Exit: 105 dlclose(alsa_lib); 106 return result; 107 } 108