alsa wav

wav_parser.h文件：

    //File   : wav_parser.h
    //Author : Loon <sepnic@gmail.com> 

    #ifndef __WAV_PARSER_H
    #define __WAV_PARSER_H 

    typedef unsigned char  uint8_t;
    typedef unsigned short uint16_t;
    typedef unsigned int   uint32_t; 

    #if __BYTE_ORDER == __LITTLE_ENDIAN
    #define COMPOSE_ID(a,b,c,d) ((a) | ((b)<<8) | ((c)<<16) | ((d)<<24))
    #define LE_SHORT(v)           (v)
    #define LE_INT(v)               (v)
    #define BE_SHORT(v)           bswap_16(v)
    #define BE_INT(v)               bswap_32(v)
    #elif __BYTE_ORDER == __BIG_ENDIAN
    #define COMPOSE_ID(a,b,c,d) ((d) | ((c)<<8) | ((b)<<16) | ((a)<<24))
    #define LE_SHORT(v)           bswap_16(v)
    #define LE_INT(v)               bswap_32(v)
    #define BE_SHORT(v)           (v)
    #define BE_INT(v)               (v)
    #else
    #error "Wrong endian"
    #endif 

    #define WAV_RIFF        COMPOSE_ID('R','I','F','F')
    #define WAV_WAVE        COMPOSE_ID('W','A','V','E')
    #define WAV_FMT         COMPOSE_ID('f','m','t',' ')
    #define WAV_DATA        COMPOSE_ID('d','a','t','a') 

    /* WAVE fmt block constants from Microsoft mmreg.h header */
    #define WAV_FMT_PCM             0x0001
    #define WAV_FMT_IEEE_FLOAT      0x0003
    #define WAV_FMT_DOLBY_AC3_SPDIF 0x0092
    #define WAV_FMT_EXTENSIBLE      0xfffe 

    /* Used with WAV_FMT_EXTENSIBLE format */
    #define WAV_GUID_TAG "/x00/x00/x00/x00/x10/x00/x80/x00/x00/xAA/x00/x38/x9B/x71" 

    /* it's in chunks like .voc and AMIGA iff, but my source say there
       are in only in this combination, so I combined them in one header;
       it works on all WAVE-file I have
     */
    typedef struct WAVHeader {
        uint32_t magic;     /* 'RIFF' */
        uint32_t length;        /* filelen */
        uint32_t type;      /* 'WAVE' */
    } WAVHeader_t; 

    typedef struct WAVFmt {
        uint32_t magic;  /* 'FMT '*/
        uint32_t fmt_size; /* 16 or 18 */
        uint16_t format;        /* see WAV_FMT_* */
        uint16_t channels;
        uint32_t sample_rate;   /* frequence of sample */
        uint32_t bytes_p_second;
        uint16_t blocks_align;  /* samplesize; 1 or 2 bytes */
        uint16_t sample_length; /* 8, 12 or 16 bit */
    } WAVFmt_t; 

    typedef struct WAVFmtExtensible {
        WAVFmt_t format;
        uint16_t ext_size;
        uint16_t bit_p_spl;
        uint32_t channel_mask;
        uint16_t guid_format;   /* WAV_FMT_* */
        uint8_t guid_tag[];   /* WAV_GUID_TAG */
    } WAVFmtExtensible_t; 

    typedef struct WAVChunkHeader {
        uint32_t type;      /* 'data' */
        uint32_t length;        /* samplecount */
    } WAVChunkHeader_t; 

    typedef struct WAVContainer {
        WAVHeader_t header;
        WAVFmt_t format;
        WAVChunkHeader_t chunk;
    } WAVContainer_t; 

    int WAV_ReadHeader(int fd, WAVContainer_t *container); 

    int WAV_WriteHeader(int fd, WAVContainer_t *container); 

    #endif /* #ifndef __WAV_PARSER_H */ 

wav_parser.c

    //File   : wav_parser.c
    //Author : Loon <sepnic@gmail.com> 

    #include <assert.h>
    #include <stdio.h>
    #include <stdlib.h>
    #include <unistd.h>
    #include <fcntl.h> 

    #include "wav_parser.h" 

    #define WAV_PRINT_MSG 

    char *WAV_P_FmtString(uint16_t fmt)
    {
        switch (fmt) {
        case WAV_FMT_PCM:
            return "PCM";
            break;
        case WAV_FMT_IEEE_FLOAT:
            return "IEEE FLOAT";
            break;
        case WAV_FMT_DOLBY_AC3_SPDIF:
            return "DOLBY AC3 SPDIF";
            break;
        case WAV_FMT_EXTENSIBLE:
            return "EXTENSIBLE";
            break;
        default:
            break;
        } 

        return "NON Support Fmt";
    } 

    void WAV_P_PrintHeader(WAVContainer_t *container)
    {
        printf("+++++++++++++++++++++++++++/n");
        printf("/n"); 

        printf("File Magic:         [%c%c%c%c]/n",
            (char)(container->header.magic),
            (char)(container->header.magic>>),
            (char)(container->header.magic>>),
            (char)(container->header.magic>>));
    printf("File Length:        [%d]/n", container->header.length);
    printf("File Type:          [%c%c%c%c]/n",
      (char)(container->header.type),
      (char)(container->header.type>>),
      (char)(container->header.type>>),
      (char)(container->header.type>>));
    printf("/n");
    printf("Fmt Magic:          [%c%c%c%c]/n",
      (char)(container->format.magic),
      (char)(container->format.magic>>),
      (char)(container->format.magic>>),
      (char)(container->format.magic>>));
    printf("Fmt Size:           [%d]/n", container->format.fmt_size);
    printf("Fmt Format:         [%s]/n", WAV_P_FmtString(container->format.format));
    printf("Fmt Channels:       [%d]/n", container->format.channels);
    printf("Fmt Sample_rate:    [%d](HZ)/n", container->format.sample_rate);
    printf("Fmt Bytes_p_second: [%d]/n", container->format.bytes_p_second);
    printf("Fmt Blocks_align:   [%d]/n", container->format.blocks_align);
    printf("Fmt Sample_length:  [%d]/n", container->format.sample_length); 

        printf("/n"); 

        printf("Chunk Type:         [%c%c%c%c]/n",
            (char)(container->chunk.type),
            (char)(container->chunk.type>>),
            (char)(container->chunk.type>>),
            (char)(container->chunk.type>>));
        printf("Chunk Length: [%d]/n", container->chunk.length); 

        printf("/n");
        printf("++++++++++++++++++++++++++++++++++++++/n");
    } 

    int WAV_P_CheckValid(WAVContainer_t *container)
    {
        if (container->header.magic != WAV_RIFF ||
            container->header.type != WAV_WAVE ||
            container->format.magic != WAV_FMT ||
            container->format.fmt_size != LE_INT() ||
    (container->format.channels != LE_SHORT() && container->format.channels != LE_SHORT())
     || container->chunk.type != WAV_DATA) {
            fprintf(stderr, "non standard wav file./n");
            return -;
        } 

        return ;
    } 

    int WAV_ReadHeader(int fd, WAVContainer_t *container)
    {
        assert((fd >=) && container); 

    if (read(fd,&container->header,sizeof(container->header))!=sizeof(container->header)
    ||read(fd,&container->format,sizeof(container->format))!=sizeof(container->format)
    ||read(fd,&container->chunk,sizeof(container->chunk))!=sizeof(container->chunk)){

            fprintf(stderr, "Error WAV_ReadHeader/n");
            return -;
        } 

        if (WAV_P_CheckValid(container) < )
            return -; 

    #ifdef WAV_PRINT_MSG
        WAV_P_PrintHeader(container);
    #endif 

        return ;
    } 

    int WAV_WriteHeader(int fd, WAVContainer_t *container)
    {
        assert((fd >=) && container); 

        if (WAV_P_CheckValid(container) < )
            return -; 

    if (write(fd,&container->header,sizeof(container->header))!=sizeof(container->header)
    ||write(fd,&container->format,sizeof(container->format))!=sizeof(container->format)
    ||write(fd,&container->chunk,sizeof(container->chunk))!=sizeof(container->chunk)) {
            fprintf(stderr, "Error WAV_WriteHeader/n");
            return -;
        } 

    #ifdef WAV_PRINT_MSG
        WAV_P_PrintHeader(container);
    #endif 

        return ;
    } 

sndwav_common.h

    //File   : sndwav_common.h
    //Author : Loon <sepnic@gmail.com> 

    #ifndef __SNDWAV_COMMON_H
    #define __SNDWAV_COMMON_H 

    #include <stdio.h>
    #include <stdlib.h>
    #include <unistd.h>
    #include <fcntl.h>
    #include "wav_parser.h" 

    typedef long long off64_t; 

    typedef struct SNDPCMContainer {
        snd_pcm_t *handle;
        snd_output_t *log;
        snd_pcm_uframes_t chunk_size;
        snd_pcm_uframes_t buffer_size;
        snd_pcm_format_t format;
        uint16_t channels;
        size_t chunk_bytes;
        size_t bits_per_sample;
        size_t bits_per_frame; 

        uint8_t *data_buf;
    } SNDPCMContainer_t; 

    ssize_t SNDWAV_ReadPcm(SNDPCMContainer_t *sndpcm, size_t rcount); 

    ssize_t SNDWAV_WritePcm(SNDPCMContainer_t *sndpcm, size_t wcount); 

    int SNDWAV_SetParams(SNDPCMContainer_t *sndpcm, WAVContainer_t *wav);
    #endif /* #ifndef __SNDWAV_COMMON_H */ 

sndwav_common.c

    #include <assert.h>
    #include <stdio.h>
    #include <stdlib.h>
    #include <unistd.h>
    #include <fcntl.h>
    #include <alsa/asoundlib.h> 

    #include "sndwav_common.h" 

    int SNDWAV_P_GetFormat(WAVContainer_t *wav, snd_pcm_format_t *snd_format)
    {
        if (LE_SHORT(wav->format.format) != WAV_FMT_PCM)
            return -; 

        switch (LE_SHORT(wav->format.sample_length)) {
        case :
            *snd_format = SND_PCM_FORMAT_S16_LE;
            break;
        case :
            *snd_format = SND_PCM_FORMAT_U8;
            break;
        default:
            *snd_format = SND_PCM_FORMAT_UNKNOWN;
            break;
        } 

        return ;
    } 

    ssize_t SNDWAV_ReadPcm(SNDPCMContainer_t *sndpcm, size_t rcount)
    {
        ssize_t r;
        size_t result = ;
        size_t count = rcount;
        uint8_t *data = sndpcm->data_buf; 

        if (count != sndpcm->chunk_size) {
            count = sndpcm->chunk_size;
        } 

        while (count > ) {
            r = snd_pcm_readi(sndpcm->handle, data, count);
            if (r == -EAGAIN || (r >=  && (size_t)r < count)) {
    snd_pcm_wait(sndpcm->handle, );
            } else if (r == -EPIPE) {
    snd_pcm_prepare(sndpcm->handle);
    fprintf(stderr, "<<<<<<<<<<<<<<< Buffer Underrun >>>>>>>>>>>>>>>/n");
            } else if (r == -ESTRPIPE) {
    fprintf(stderr, "<<<<<<<<<<<<<<< Need suspend >>>>>>>>>>>>>>>/n");
            } else if (r < ) {
    fprintf(stderr, "Error snd_pcm_writei: [%s]", snd_strerror(r));
    exit(-);
            } 

            if (r > ) {
                result += r;
                count -= r;
                data += r * sndpcm->bits_per_frame / ;
            }
        }
        return rcount;
    } 

    ssize_t SNDWAV_WritePcm(SNDPCMContainer_t *sndpcm, size_t wcount)
    {
        ssize_t r;
        ssize_t result = ;
        uint8_t *data = sndpcm->data_buf; 

        if (wcount < sndpcm->chunk_size) {
            snd_pcm_format_set_silence(sndpcm->format,
                data + wcount * sndpcm->bits_per_frame / ,
                (sndpcm->chunk_size - wcount) * sndpcm->channels);
            wcount = sndpcm->chunk_size;
        }
        while (wcount > ) {
            r = snd_pcm_writei(sndpcm->handle, data, wcount);
            if (r == -EAGAIN || (r >=  && (size_t)r < wcount)) {
    snd_pcm_wait(sndpcm->handle, );
            } else if (r == -EPIPE) {
    snd_pcm_prepare(sndpcm->handle);
    fprintf(stderr, "<<<<<<<<<<<<<<< Buffer Underrun >>>>>>>>>>>>>>>/n");
            } else if (r == -ESTRPIPE) {
    fprintf(stderr, "<<<<<<<<<<<<<<< Need suspend >>>>>>>>>>>>>>>/n");
            } else if (r < ) {
    fprintf(stderr, "Error snd_pcm_writei: [%s]", snd_strerror(r));
    exit(-);
            }
            if (r > ) {
                result += r;
                wcount -= r;
                data += r * sndpcm->bits_per_frame / ;
            }
        }
        return result;
    } 

    int SNDWAV_SetParams(SNDPCMContainer_t *sndpcm, WAVContainer_t *wav)
    {
        snd_pcm_hw_params_t *hwparams;
        snd_pcm_format_t format;
        uint32_t exact_rate;
        uint32_t buffer_time, period_time; 

        /* Allocate the snd_pcm_hw_params_t structure on the stack. */
        snd_pcm_hw_params_alloca(&hwparams); 

        /* Init hwparams with full configuration space */
        if (snd_pcm_hw_params_any(sndpcm->handle, hwparams) < ) {
            fprintf(stderr, "Error snd_pcm_hw_params_any/n");
            goto ERR_SET_PARAMS;
        } 

        if (snd_pcm_hw_params_set_access(sndpcm->handle, hwparams
    , SND_PCM_ACCESS_RW_INTERLEAVED) < ) {
            fprintf(stderr, "Error snd_pcm_hw_params_set_access/n");
            goto ERR_SET_PARAMS;
        } 

        /* Set sample format */
        if (SNDWAV_P_GetFormat(wav, &format) < ) {
            fprintf(stderr, "Error get_snd_pcm_format/n");
            goto ERR_SET_PARAMS;
        }
        if (snd_pcm_hw_params_set_format(sndpcm->handle, hwparams, format) < ) {
            fprintf(stderr, "Error snd_pcm_hw_params_set_format/n");
            goto ERR_SET_PARAMS;
        }
        sndpcm->format = format; 

        /* Set number of channels */
        if (snd_pcm_hw_params_set_channels(sndpcm->handle, hwparams
    , LE_SHORT(wav->format.channels)) < ) {
            fprintf(stderr, "Error snd_pcm_hw_params_set_channels/n");
            goto ERR_SET_PARAMS;
        }
        sndpcm->channels = LE_SHORT(wav->format.channels); 

        /* Set sample rate. If the exact rate is not supported */
        /* by the hardware, use nearest possible rate.         */
        exact_rate = LE_INT(wav->format.sample_rate);
    if (snd_pcm_hw_params_set_rate_near(sndpcm->handle, hwparams, &exact_rate, ) < ) {
            fprintf(stderr, "Error snd_pcm_hw_params_set_rate_near/n");
            goto ERR_SET_PARAMS;
        }
        if (LE_INT(wav->format.sample_rate) != exact_rate) {
            fprintf(stderr
    , "The rate %d Hz is not supported by your hardware./n ==> Using %d Hz instead./n",
                LE_INT(wav->format.sample_rate), exact_rate);
        } 

        if (snd_pcm_hw_params_get_buffer_time_max(hwparams, &buffer_time, ) < ) {
            fprintf(stderr, "Error snd_pcm_hw_params_get_buffer_time_max/n");
            goto ERR_SET_PARAMS;
        }
        if (buffer_time > ) buffer_time = ;
        period_time = buffer_time / ; 

        if (snd_pcm_hw_params_set_buffer_time_near(sndpcm->handle, hwparams
    , &buffer_time, ) < ) {
            fprintf(stderr, "Error snd_pcm_hw_params_set_buffer_time_near/n");
            goto ERR_SET_PARAMS;
        } 

        if (snd_pcm_hw_params_set_period_time_near(sndpcm->handle, hwparams
    , &period_time, ) < ) {
            fprintf(stderr, "Error snd_pcm_hw_params_set_period_time_near/n");
            goto ERR_SET_PARAMS;
        } 

        /* Set hw params */
        if (snd_pcm_hw_params(sndpcm->handle, hwparams) < ) {
            fprintf(stderr, "Error snd_pcm_hw_params(handle, params)/n");
            goto ERR_SET_PARAMS;
        } 

        snd_pcm_hw_params_get_period_size(hwparams, &sndpcm->chunk_size, );
        snd_pcm_hw_params_get_buffer_size(hwparams, &sndpcm->buffer_size);
        if (sndpcm->chunk_size == sndpcm->buffer_size) {
            fprintf(stderr, ("Can't use period equal to buffer size (%lu == %lu)/n")
    , sndpcm->chunk_size, sndpcm->buffer_size);
            goto ERR_SET_PARAMS;
        } 

        sndpcm->bits_per_sample = snd_pcm_format_physical_width(format);
        sndpcm->bits_per_frame = sndpcm->bits_per_sample * LE_SHORT(wav->format.channels); 

        sndpcm->chunk_bytes = sndpcm->chunk_size * sndpcm->bits_per_frame / ; 

        /* Allocate audio data buffer */
        sndpcm->data_buf = (uint8_t *)malloc(sndpcm->chunk_bytes);
        if (!sndpcm->data_buf) {
            fprintf(stderr, "Error malloc: [data_buf]/n");
            goto ERR_SET_PARAMS;
        } 

        return ; 

    ERR_SET_PARAMS:
        return -;
    } 

lplay.c

    #include <stdio.h>
    #include <malloc.h>
    #include <unistd.h>
    #include <stdlib.h>
    #include <string.h>
    #include <getopt.h>
    #include <fcntl.h>
    #include <ctype.h>
    #include <errno.h>
    #include <limits.h>
    #include <time.h>
    #include <locale.h>
    #include <sys/unistd.h>
    #include <sys/stat.h>
    #include <sys/types.h>
    #include <alsa/asoundlib.h>
    #include <assert.h>
    #include "wav_parser.h"
    #include "sndwav_common.h" 

    ssize_t SNDWAV_P_SaveRead(int fd, void *buf, size_t count)
    {
        ssize_t result = , res; 

        while (count > ) {
            if ((res = read(fd, buf, count)) == )
                break;
            if (res < )
                return result >  ? result : res;
            count -= res;
            result += res;
            buf = (char *)buf + res;
        }
        return result;
    } 

    void SNDWAV_Play(SNDPCMContainer_t *sndpcm, WAVContainer_t *wav, int fd)
    {
        int load, ret;
        off64_t written = ;
        off64_t c;
        off64_t count = LE_INT(wav->chunk.length); 

        load = ;
        while (written < count) {
            /* Must read [chunk_bytes] bytes data enough. */
            do {
                c = count - written;
                if (c > sndpcm->chunk_bytes)
                    c = sndpcm->chunk_bytes;
                c -= load; 

                if (c == )
                    break;
                ret = SNDWAV_P_SaveRead(fd, sndpcm->data_buf + load, c);
                if (ret < ) {
                    fprintf(stderr, "Error safe_read/n");
                    exit(-);
                }
                if (ret == )
                    break;
                load += ret;
            } while ((size_t)load < sndpcm->chunk_bytes); 

            /* Transfer to size frame */
            load = load *  / sndpcm->bits_per_frame;
            ret = SNDWAV_WritePcm(sndpcm, load);
            if (ret != load)
                break; 

            ret = ret * sndpcm->bits_per_frame / ;
            written += ret;
            load = ;
        }
    } 

    int main(int argc, char *argv[])
    {
        char *filename;
        char *devicename = "default";
        int fd;
        WAVContainer_t wav;
        SNDPCMContainer_t playback; 

        if (argc != ) {
            fprintf(stderr, "Usage: ./lplay <FILENAME>/n");
            return -;
        } 

        memset(&playback, 0x0, sizeof(playback)); 

        filename = argv[];
        fd = open(filename, O_RDONLY);
        if (fd < ) {
            fprintf(stderr, "Error open [%s]/n", filename);
            return -;
        } 

        if (WAV_ReadHeader(fd, &wav) < ) {
            fprintf(stderr, "Error WAV_Parse [%s]/n", filename);
            goto Err;
        } 

        if (snd_output_stdio_attach(&playback.log, stderr, ) < ) {
            fprintf(stderr, "Error snd_output_stdio_attach/n");
            goto Err;
        } 

        if (snd_pcm_open(&playback.handle, devicename, SND_PCM_STREAM_PLAYBACK, ) < ) {
            fprintf(stderr, "Error snd_pcm_open [ %s]/n", devicename);
            goto Err;
        } 

        if (SNDWAV_SetParams(&playback, &wav) < ) {
            fprintf(stderr, "Error set_snd_pcm_params/n");
            goto Err;
        }
        snd_pcm_dump(playback.handle, playback.log); 

        SNDWAV_Play(&playback, &wav, fd); 

        snd_pcm_drain(playback.handle); 

        close(fd);
        free(playback.data_buf);
        snd_output_close(playback.log);
        snd_pcm_close(playback.handle);
        return ; 

    Err:
        close(fd);
        if (playback.data_buf) free(playback.data_buf);
        if (playback.log) snd_output_close(playback.log);
        if (playback.handle) snd_pcm_close(playback.handle);
        return -;
    } 

lrecord.c

    #include <stdio.h>
    #include <malloc.h>
    #include <unistd.h>
    #include <stdlib.h>
    #include <string.h>
    #include <getopt.h>
    #include <fcntl.h>
    #include <ctype.h>
    #include <errno.h>
    #include <limits.h>
    #include <time.h>
    #include <locale.h>
    #include <sys/unistd.h>
    #include <sys/stat.h>
    #include <sys/types.h>
    #include <alsa/asoundlib.h>
    #include <assert.h>
    #include "wav_parser.h"
    #include "sndwav_common.h" 

    #define DEFAULT_CHANNELS         (2)
    #define DEFAULT_SAMPLE_RATE      (8000)
    #define DEFAULT_SAMPLE_LENGTH    (16)
    #define DEFAULT_DURATION_TIME    (10) 

    int SNDWAV_PrepareWAVParams(WAVContainer_t *wav)
    {
        assert(wav); 

        uint16_t channels = DEFAULT_CHANNELS;
        uint16_t sample_rate = DEFAULT_SAMPLE_RATE;
        uint16_t sample_length = DEFAULT_SAMPLE_LENGTH;
        uint32_t duration_time = DEFAULT_DURATION_TIME; 

        /* Const */
        wav->header.magic = WAV_RIFF;
        wav->header.type = WAV_WAVE;
        wav->format.magic = WAV_FMT;
        wav->format.fmt_size = LE_INT();
        wav->format.format = LE_SHORT(WAV_FMT_PCM);
        wav->chunk.type = WAV_DATA; 

        /* User definition */
        wav->format.channels = LE_SHORT(channels);
        wav->format.sample_rate = LE_INT(sample_rate);
        wav->format.sample_length = LE_SHORT(sample_length); 

        /* See format of wav file */
    wav->format.blocks_align = LE_SHORT(channels * sample_length / );
    wav->format.bytes_p_second = LE_INT((uint16_t)(wav->format.blocks_align) * sample_rate); 

    wav->chunk.length = LE_INT(duration_time * (uint32_t)(wav->format.bytes_p_second));
    wav->header.length = LE_INT((uint32_t)(wav->chunk.length) +/
            sizeof(wav->chunk) + sizeof(wav->format) + sizeof(wav->header) - ); 

        return ;
    } 

    void SNDWAV_Record(SNDPCMContainer_t *sndpcm, WAVContainer_t *wav, int fd)
    {
        off64_t rest;
        size_t c, frame_size; 

        if (WAV_WriteHeader(fd, wav) < ) {
            exit(-);
        } 

        rest = wav->chunk.length;
        while (rest > ) {
            c = (rest <= (off64_t)sndpcm->chunk_bytes) ? (size_t)rest : sndpcm->chunk_bytes;
            frame_size = c *  / sndpcm->bits_per_frame;
            if (SNDWAV_ReadPcm(sndpcm, frame_size) != frame_size)
                break; 

            if (write(fd, sndpcm->data_buf, c) != c) {
                fprintf(stderr, "Error SNDWAV_Record[write]/n");
                exit(-);
            } 

            rest -= c;
        }
    } 

    int main(int argc, char *argv[])
    {
        char *filename;
        char *devicename = "default";
        int fd;
        WAVContainer_t wav;
        SNDPCMContainer_t record; 

        if (argc != ) {
            fprintf(stderr, "Usage: ./lrecord <FILENAME>/n");
            return -;
        } 

        memset(&record, 0x0, sizeof(record)); 

        filename = argv[];
        remove(filename);
        if ((fd = open(filename, O_WRONLY | O_CREAT, )) == -) {
            fprintf(stderr, "Error open: [%s]/n", filename);
            return -;
        } 

        if (snd_output_stdio_attach(&record.log, stderr, ) < ) {
            fprintf(stderr, "Error snd_output_stdio_attach/n");
            goto Err;
        } 

        if (snd_pcm_open(&record.handle, devicename, SND_PCM_STREAM_CAPTURE, ) < ) {
            fprintf(stderr, "Error snd_pcm_open [ %s]/n", devicename);
            goto Err;
        } 

        if (SNDWAV_PrepareWAVParams(&wav) < ) {
            fprintf(stderr, "Error SNDWAV_PrepareWAVParams/n");
            goto Err;
        } 

        if (SNDWAV_SetParams(&record, &wav) < ) {
            fprintf(stderr, "Error set_snd_pcm_params/n");
            goto Err;
        }
        snd_pcm_dump(record.handle, record.log); 

        SNDWAV_Record(&record, &wav, fd); 

        snd_pcm_drain(record.handle); 

        close(fd);
        free(record.data_buf);
        snd_output_close(record.log);
        snd_pcm_close(record.handle);
        return ; 

    Err:
        close(fd);
        remove(filename);
        if (record.data_buf) free(record.data_buf);
        if (record.log) snd_output_close(record.log);
        if (record.handle) snd_pcm_close(record.handle);
        return -;
    } 

makefile

CC =/home/yuanpengjun/ngi/prebuilt/toolchains/arm-fsl-Linux-gnueabi/4.6./bin/arm-fsl-linux-gnueabi-gcc
CFLAGS = -g -Wall -O0 -I/home/yuanpengjun/ngi/externals/alsa-lib/include
LIBS = -L/home/yuanpengjun/ngi/out/target/product/rome/system/usr/lib -lasound

lplay: lplay.o sndwav_common.o wav_parser.o
 $(CC) $(CFLAGS) lplay.o sndwav_common.o wav_parser.o -o lplay $(LIBS)

lplay.o: lplay.c  sndwav_common.h wav_parser.h

$(CC) $(CFLAGS) -c lplay.c  

lrecord: lrecord.o sndwav_common.o wav_parser.o

 $(CC) $(CFLAGS) lrecord.o sndwav_common.o wav_parser.o -o lrecord $(LIBS)

lrecord.o: lrecord.c sndwav_common.h  wav_parser.h

$(CC) $(CFLAGS) -c lrecord.c 

sndwav_common.o: sndwav_common.c sndwav_common.h

$(CC) $(CFLAGS) -c sndwav_common.c 

wav_parser.o: wav_parser.c wav_parser.h

$(CC) $(CFLAGS) -c wav_parser.c

clean:

rm lplay lrecord *.o