完整的编译包（android平台）： 链接：http://pan.baidu.com/s/1qXMTT7I 密码：2bow
/* * ALSA parameter test program * * Copyright (c) 2007 Volker Schatz (alsacap at the domain volkerschatz.com) * * Permission to use, copy, modify, and/or distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF * CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. * * compile with: gcc -o alsacap alsacap.c -lasound */ /*============================================================================ Includes ============================================================================*/ #include <stdlib.h> #include <stdio.h> #include <alsa/asoundlib.h> #include <errno.h> #include <string.h> #include <dlfcn.h> #include <sched.h> #include <getopt.h> #include <sys/time.h> #include <math.h> /*============================================================================ Constant and type definitions ============================================================================*/ #define RATE_KHZ_LIMIT 200 #define HWP_END 0 #define HWP_RATE 1 #define HWP_NCH 2 #define HWP_FORMAT 3 #define SIZE_HWP 7 typedef struct { int recdevices, verbose, card, dev; char *device; int hwparams[SIZE_HWP]; } aiopts; /*============================================================================ Global variables ============================================================================*/ static snd_ctl_t *handle= NULL; static snd_pcm_t *pcm= NULL; static snd_ctl_card_info_t *info; static snd_pcm_info_t *pcminfo; static snd_pcm_hw_params_t *pars; static snd_pcm_format_mask_t *fmask; /*============================================================================ Prototypes ============================================================================*/ void usagemsg(int code); void errnumarg(char optchar); void errarg(char optchar); void errtoomany(); void scancards(snd_pcm_stream_t stream, int thecard, int thedev); int sc_errcheck(int retval, const char *doingwhat, int cardnr, int devnr); void testconfig(snd_pcm_stream_t stream, const char *device, const int *hwpars); void tc_errcheck(int retval, const char *doingwhat); const char *alsaerrstr(const int errcode); const char *dirstr(int dir); int parse_alsaformats(const char *fmtstr); const char *alsafmtstr(int fmtnum); void printfmtmask(const snd_pcm_format_mask_t *fmask); /*============================================================================ Main program ============================================================================*/ int main(int argc, char **argv) { aiopts options= { 0, 1, -1, -1, NULL }; snd_pcm_stream_t stream; char *argpar; int argind, hwpind; snd_ctl_card_info_alloca(&info); snd_pcm_info_alloca(&pcminfo); snd_pcm_hw_params_alloca(&pars); snd_pcm_format_mask_alloca(&fmask); hwpind= 0; for( argind= 1; argind< argc; ++argind ) { if( argv[argind][0]!='-' ) { fprintf(stderr, "Unrecognised command-line argument `%s'. ", argv[argind]); usagemsg(1); } if( argv[argind][2] ) argpar= argv[argind]+2; else { if( argind+1 >= argc ) argpar= NULL; else argpar= argv[argind+1]; } if( argv[argind][1]=='h' || !strcmp(argv[argind]+1, "-help") ) usagemsg(0); else if( argv[argind][1]=='R' ) { options.recdevices= 1; argpar= NULL; // set to NULL if unused to keep track of next arg index } else if( argv[argind][1]=='C' ) { if( !argpar || !isdigit(*argpar) ) errnumarg('C'); options.card= strtol(argpar, NULL, 0); } else if( argv[argind][1]=='D' ) { if( !argpar || !isdigit(*argpar) ) errnumarg('D'); options.dev= strtol(argpar, NULL, 0); } else if( argv[argind][1]=='d' ) { if( !argpar ) errarg('d'); options.device= argpar; } else if( argv[argind][1]=='r' ) { if( !argpar || !isdigit(*argpar) ) errnumarg('r'); if( hwpind+3 > SIZE_HWP ) errtoomany(); options.hwparams[hwpind++]= HWP_RATE; options.hwparams[hwpind]= strtol(argpar, NULL, 0); if( options.hwparams[hwpind] <= RATE_KHZ_LIMIT ) options.hwparams[hwpind] *= 1000; // sanity check: Hz or kHz ? ++hwpind; } else if( argv[argind][1]=='c' ) { if( !argpar || !isdigit(*argpar) ) errnumarg('c'); if( hwpind+3 > SIZE_HWP ) errtoomany(); options.hwparams[hwpind++]= HWP_NCH; options.hwparams[hwpind++]= strtol(argpar, NULL, 0); } else if( argv[argind][1]=='f' ) { if( !argpar ) errarg('f'); if( hwpind+3 > SIZE_HWP ) errtoomany(); options.hwparams[hwpind++]= HWP_FORMAT; options.hwparams[hwpind++]= parse_alsaformat(argpar); } else { fprintf(stderr, "Unrecognised command-line option `%s'. ", argv[argind]); usagemsg(1); } if( argpar && !argv[argind][2] ) ++argind; // additional increment if separate parameter argument was used } options.hwparams[hwpind]= HWP_END; if( options.dev >= 0 && options.card < 0 ) { fprintf(stderr, "The card has to be specified with -C if a device number is given (-D). "); exit(1); } if( options.device && (options.card>=0 || options.dev>=0) ) { fprintf(stderr, "Specifying a device name (-d) and a card and possibly device number (-C, -D) is mutually exclusive. "); exit(1); } stream= options.recdevices? SND_PCM_STREAM_CAPTURE : SND_PCM_STREAM_PLAYBACK; if( !options.device ) scancards(stream, options.card, options.dev); else testconfig(stream, options.device, options.hwparams); return 0; } /*============================================================================ Usage message and command-line argument error functions ============================================================================*/ void usagemsg(int code) { fprintf(stderr, "Usage: alsacap [-R] [-C <card #> [-D <device #>]] " " alsacap [-R] -d <device name> [-r <rate>|-c <# of channels>|-f <sample format>]... " "ALSA capability lister. " "First form: Scans one or all soundcards known to ALSA for devices, " "subdevices and parameter ranges. -R causes a scan for recording " "rather than playback devices. The other options specify the sound " "card and possibly the device by number. " "Second form: Displays ranges of configuration parameters for the given " "ALSA device. Unlike with the first form, a non-hardware device may be " "given. Up to three optional command-line arguments fix the rate, " "number of channels and sample format in the order in which they are " "given. The remaining parameter ranges are output. If unique, the " "number of significant bits of the sample values is output. (Some " "sound cards ignore some of the bits.) "); exit(code); } void errnumarg(char optchar) { fprintf(stderr, "The -%c option requires a numerical argument! Aborting. ", optchar); exit(1); } void errarg(char optchar) { fprintf(stderr, "The -%c option requires an argument! Aborting. ", optchar); exit(1); } void errtoomany() { fprintf(stderr, "Too many -r/-c/-f options given! (Maximum is %d.) Aborting. ", (SIZE_HWP-1)/2); exit(1); } /*============================================================================ Function for scanning all cards ============================================================================*/ #define HWCARDTEMPL "hw:%d" #define HWDEVTEMPL "hw:%d,%d" #define HWDEVLEN 32 void scancards(snd_pcm_stream_t stream, int thecard, int thedev) { char hwdev[HWDEVLEN+1]; unsigned min, max; int card, err, dev, subd, nsubd; printf("*** Scanning for %s devices", stream==SND_PCM_STREAM_CAPTURE? "recording" : "playback"); if( thecard >= 0 ) printf(" on card %d", thecard); if( thedev >= 0 ) printf(", device %d", thedev); printf(" *** "); hwdev[HWDEVLEN]= 0; if( thecard >= 0 ) card= thecard; else { card= -1; if( snd_card_next(&card) < 0 ) return; } while( card >= 0 ) { snprintf(hwdev, HWDEVLEN, HWCARDTEMPL, card); err= snd_ctl_open(&handle, hwdev, 0); if( sc_errcheck(err, "opening control interface", card, -1) ) goto nextcard; err= snd_ctl_card_info(handle, info); if( sc_errcheck(err, "obtaining card info", card, -1) ) { snd_ctl_close(handle); goto nextcard; } printf("Card %d, ID `%s', name `%s' ", card, snd_ctl_card_info_get_id(info), snd_ctl_card_info_get_name(info)); if( thedev >= 0 ) dev= thedev; else { dev= -1; if( snd_ctl_pcm_next_device(handle, &dev) < 0 ) { snd_ctl_close(handle); goto nextcard; } } while( dev >= 0 ) { snd_pcm_info_set_device(pcminfo, dev); snd_pcm_info_set_subdevice(pcminfo, 0); snd_pcm_info_set_stream(pcminfo, stream); err= snd_ctl_pcm_info(handle, pcminfo); if( thedev<0 && err == -ENOENT ) goto nextdev; if( sc_errcheck(err, "obtaining device info", card, dev) ) goto nextdev; nsubd= snd_pcm_info_get_subdevices_count(pcminfo); if( sc_errcheck(nsubd, "obtaining device info", card, dev) ) goto nextdev; printf(" Device %d, ID `%s', name `%s', %d subdevices (%d available) ", dev, snd_pcm_info_get_id(pcminfo), snd_pcm_info_get_name(pcminfo), nsubd, snd_pcm_info_get_subdevices_avail(pcminfo)); snprintf(hwdev, HWDEVLEN, HWDEVTEMPL, card, dev); err= snd_pcm_open(&pcm, hwdev, stream, SND_PCM_NONBLOCK); if( sc_errcheck(err, "opening sound device", card, dev) ) goto nextdev; err= snd_pcm_hw_params_any(pcm, pars); if( sc_errcheck(err, "obtaining hardware parameters", card, dev) ) { snd_pcm_close(pcm); goto nextdev; } snd_pcm_hw_params_get_channels_min(pars, &min); snd_pcm_hw_params_get_channels_max(pars, &max); if( min == max ) if( min == 1 ) printf(" 1 channel, "); else printf(" %d channels, ", min); else printf(" %u..%u channels, ", min, max); snd_pcm_hw_params_get_rate_min(pars, &min, NULL); snd_pcm_hw_params_get_rate_max(pars, &max, NULL); printf("sampling rate %u..%u Hz Sample formats: ", min, max); snd_pcm_hw_params_get_format_mask(pars, fmask); printfmtmask(fmask); snd_pcm_close(pcm); printf(" "); pcm= NULL; for( subd= 0; subd< nsubd; ++subd ) { snd_pcm_info_set_subdevice(pcminfo, subd); err= snd_ctl_pcm_info(handle, pcminfo); if( sc_errcheck(err, "obtaining subdevice info", card, dev) ) goto nextdev; printf(" Subdevice %d, name `%s' ", subd, snd_pcm_info_get_subdevice_name(pcminfo)); } nextdev: if( thedev >= 0 || snd_ctl_pcm_next_device(handle, &dev) < 0 ) break; } snd_ctl_close(handle); nextcard: if( thecard >= 0 || snd_card_next(&card) < 0 ) break; } } int sc_errcheck(int retval, const char *doingwhat, int cardnr, int devnr) { if( retval<0 ) { if( devnr>= 0 ) fprintf(stderr, "Error %s for card %d, device %d: %s. Skipping. ", doingwhat, cardnr, devnr, alsaerrstr(retval)); else fprintf(stderr, "Error %s for card %d: %s. Skipping. ", doingwhat, cardnr, alsaerrstr(retval)); return 1; } return 0; } /*============================================================================ Function for investigating device configurations ============================================================================*/ void testconfig(snd_pcm_stream_t stream, const char *device, const int *hwpars) { unsigned min, max, param; int err, count, dir, result; printf("*** Exploring configuration space of device `%s' for %s *** ", device, stream==SND_PCM_STREAM_CAPTURE? "recording" : "playback"); err= snd_pcm_open(&pcm, device, stream, SND_PCM_NONBLOCK); tc_errcheck(err, "opening sound device"); err= snd_pcm_hw_params_any(pcm, pars); tc_errcheck(err, "initialising hardware parameters"); for( count= 0; hwpars[count]!=HWP_END; count += 2 ) switch(hwpars[count]) { case HWP_RATE:param= hwpars[count+1]; err= snd_pcm_hw_params_set_rate_near(pcm, pars, ¶m, &result); if( err<0 ) fprintf(stderr, "Could not set sampling rate to %d Hz: %s. " "Continuing regardless. ", hwpars[count+1], alsaerrstr(err)); else printf("Set sampling rate %d Hz --> got %u Hz, %s requested. ", hwpars[count+1], param, dirstr(dir)); break; case HWP_NCH:err= snd_pcm_hw_params_set_channels(pcm, pars, hwpars[count+1]); if( err<0 ) fprintf(stderr, "Could not set # of channels to %d: %s. " "Continuing regardless. ", hwpars[count+1], alsaerrstr(err)); else printf("Set number of channels to %d. ", hwpars[count+1]); break; case HWP_FORMAT:err= snd_pcm_hw_params_set_format(pcm, pars, hwpars[count+1]); if( err<0 ) fprintf(stderr, "Could not set sample format to %s: %s." " Continuing regardless. ", alsafmtstr(hwpars[count+1]), alsaerrstr(err)); else printf("Set sample format to %s. ", alsafmtstr(hwpars[count+1])); break; default: break; } if( count>0 ) printf("Parameter ranges remaining after these settings: "); snd_pcm_hw_params_get_channels_min(pars, &min); snd_pcm_hw_params_get_channels_max(pars, &max); if( min==max ) if( min==1 ) printf("1 channel "); else printf("%u channels ", min); else printf("%u..%u channels ", min, max); snd_pcm_hw_params_get_rate_min(pars, &min, NULL); snd_pcm_hw_params_get_rate_max(pars, &max, NULL); if( min==max ) printf("Sampling rate %u Hz Sample formats: ", min); else printf("Sampling rate %u..%u Hz Sample formats: ", min, max); snd_pcm_hw_params_get_format_mask(pars, fmask); printfmtmask(fmask); printf(" "); result= snd_pcm_hw_params_get_sbits(pars); if( result >= 0 ) // only available if bit width of all formats is the same printf("Significant bits: %d ", result); snd_pcm_close(pcm); } void tc_errcheck(int retval, const char *doingwhat) { if( retval<0 ) { fprintf(stderr, "Error %s: %s. Aborting. ", doingwhat, alsaerrstr(retval)); if( pcm ) snd_pcm_close(pcm); exit(1); } } /*============================================================================ String-building functions ============================================================================*/ struct alsaerr { int err; char *msg; }; struct alsaerr aelist[]= { -EBADFD, "PCM device is in a bad state", -EPIPE, "An underrun occurred", -ESTRPIPE, "A suspend event occurred", -ENOTTY, "Hotplug device has been removed", -ENODEV, "Hotplug device has been removed", -ENOENT, "Device does not exist", 0, NULL }; const char *alsaerrstr(const int errcode) { struct alsaerr *search; if( errcode >= 0 ) return "No error"; for( search= aelist; search->msg && search->err!=errcode; ++search); if( search->msg ) return search->msg; else return strerror(-errcode); } const char *dirstr(int dir) { if( !dir ) return "="; else if( dir<0 ) return "<"; else return ">"; } /*============================================================================ Functions for parsing and string output of ALSA sample formats ============================================================================*/ struct fmtdef { char *fmtname; int format; }; static struct fmtdef fmtlist[]= { "S8", SND_PCM_FORMAT_S8, "U8", SND_PCM_FORMAT_U8, "S16_LE", SND_PCM_FORMAT_S16_LE, "S16_BE", SND_PCM_FORMAT_S16_BE, "U16_LE", SND_PCM_FORMAT_U16_LE, "U16_BE", SND_PCM_FORMAT_U16_BE, "S24_LE", SND_PCM_FORMAT_S24_LE, "S24_BE", SND_PCM_FORMAT_S24_BE, "U24_LE", SND_PCM_FORMAT_U24_LE, "U24_BE", SND_PCM_FORMAT_U24_BE, "S32_LE", SND_PCM_FORMAT_S32_LE, "S32_BE", SND_PCM_FORMAT_S32_BE, "U32_LE", SND_PCM_FORMAT_U32_LE, "U32_BE", SND_PCM_FORMAT_U32_BE, "FLOAT_LE", SND_PCM_FORMAT_FLOAT_LE, "FLOAT_BE", SND_PCM_FORMAT_FLOAT_BE, "FLOAT64_LE", SND_PCM_FORMAT_FLOAT64_LE, "FLOAT64_BE", SND_PCM_FORMAT_FLOAT64_BE, "IEC958_SUBFRAME_LE", SND_PCM_FORMAT_IEC958_SUBFRAME_LE, "IEC958_SUBFRAME_BE", SND_PCM_FORMAT_IEC958_SUBFRAME_BE, "MU_LAW", SND_PCM_FORMAT_MU_LAW, "A_LAW", SND_PCM_FORMAT_A_LAW, "IMA_ADPCM", SND_PCM_FORMAT_IMA_ADPCM, "MPEG", SND_PCM_FORMAT_MPEG, "GSM", SND_PCM_FORMAT_GSM, "SPECIAL", SND_PCM_FORMAT_SPECIAL, "S24_3LE", SND_PCM_FORMAT_S24_3LE, "S24_3BE", SND_PCM_FORMAT_S24_3BE, "U24_3LE", SND_PCM_FORMAT_U24_3LE, "U24_3BE", SND_PCM_FORMAT_U24_3BE, "S20_3LE", SND_PCM_FORMAT_S20_3LE, "S20_3BE", SND_PCM_FORMAT_S20_3BE, "U20_3LE", SND_PCM_FORMAT_U20_3LE, "U20_3BE", SND_PCM_FORMAT_U20_3BE, "S18_3LE", SND_PCM_FORMAT_S18_3LE, "S18_3BE", SND_PCM_FORMAT_S18_3BE, "U18_3LE", SND_PCM_FORMAT_U18_3LE, "U18_3BE", SND_PCM_FORMAT_U18_3BE, "S16", SND_PCM_FORMAT_S16, "U16", SND_PCM_FORMAT_U16, "S24", SND_PCM_FORMAT_S24, "U24", SND_PCM_FORMAT_U24, "S32", SND_PCM_FORMAT_S32, "U32", SND_PCM_FORMAT_U32, "FLOAT", SND_PCM_FORMAT_FLOAT, "FLOAT64", SND_PCM_FORMAT_FLOAT64, "IEC958_SUBFRAME", SND_PCM_FORMAT_IEC958_SUBFRAME, NULL, 0 }; int parse_alsaformat(const char *fmtstr) { struct fmtdef *search; for( search= fmtlist; search->fmtname && strcmp(search->fmtname, fmtstr); ++search ); if( !search->fmtname ) { fprintf(stderr, "Unknown sample format `%s'. Aborting. ", fmtstr); exit(1); } return search->format; } const char *alsafmtstr(int fmtnum) { struct fmtdef *search; for( search= fmtlist; search->fmtname && search->format!=fmtnum; ++search ); if( !search->fmtname ) return "(unknown)"; else return search->fmtname; } /*============================================================================ Printout functions ============================================================================*/ void printfmtmask(const snd_pcm_format_mask_t *fmask) { int fmt, prevformat= 0; for( fmt= 0; fmt <= SND_PCM_FORMAT_LAST; ++fmt ) if( snd_pcm_format_mask_test(fmask, (snd_pcm_format_t)fmt) ) { if( prevformat ) printf(", "); printf("%s", snd_pcm_format_name((snd_pcm_format_t)fmt)); prevformat= 1; } if( !prevformat ) printf("(none)"); }