audio/utilities/AudioRawPipe.cc

	AudioRawPipe.cc revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
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 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
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/*
 * Copyright 1991-2003 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <stdlib.h>
#include <unistd.h>
#include <sys/stat.h>

#include <AudioRawPipe.h>
#include <libaudio.h>
#include <audio_hdr.h>

// class AudioPipe methods

// Constructor with file descriptor, mode, and optional name
AudioRawPipe::
AudioRawPipe(
    const int       desc,       // file descriptor
    const FileAccess    acc,        // access mode
    const AudioHdr&     hdr_local,  // header
    const char      *name_local,    // name
    const off_t     off     // offset
):AudioPipe(desc, acc, name_local), offset(off)
{
    isopened = FALSE;
    setfd(desc);
    SetHeader(hdr_local);
}

// The create routine for pipes writes a file header
AudioError AudioRawPipe::
Create()
{
    AudioError  err;

    // Was the header properly set?
    err = GetHeader().Validate();
    if (err != AUDIO_SUCCESS)
        return (RaiseError(err));

    // Open fd supplied by constructor
    if (!isfdset() || opened()) {
        return (RaiseError(AUDIO_ERR_NOEFFECT, Warning));
    }

    // set flag for opened() test
    isopened = TRUE;

    // Set the actual output length to zero
    setlength(0.);

    return (AUDIO_SUCCESS);
}

// The open routine for raw pipes validates the header and
// init's the read pos to offset and sets the opened flag.
AudioError AudioRawPipe::
Open()
{
    AudioError  err;
    struct stat st;

    // The constructor should have supplied a valid fd
    // If fd is not open, or file header already decoded, skip it
    if (!isfdset() || opened())
        return (RaiseError(AUDIO_ERR_NOEFFECT, Warning));

    // Stat the file, to see if it is a regular file
    if (fstat(getfd(), &st) < 0)
        return (RaiseError(AUDIO_UNIXERROR));

    // check validity of file header
    err = GetHeader().Validate();
    if (err != AUDIO_SUCCESS) {
        (void) close(getfd());
        setfd(-1);
        return (err);
    }

    // Only trust the file size for regular files
    if (S_ISREG(st.st_mode)) {
        // for raw files - no hdr, so it's the whole file minus
        // the offset.
        setlength(GetHeader().Bytes_to_Time(st.st_size - offset));
    } else {
        // don't know ...
        setlength(AUDIO_UNKNOWN_TIME);
    }

    // set flag for opened() test
    isopened = TRUE;

    err = SetOffset(offset);

    // reset logical position to 0.0, since this is, in effect,
    // the beginning of the file.
    SetReadPosition(0.0, Absolute);

    return (err);
}

Boolean AudioRawPipe::
opened() const
{
    return (isopened);
}

AudioError AudioRawPipe::
SetOffset(off_t val)
{
    off_t       setting = 0;
    AudioError  err;

    // only read only files for now
    if (GetAccess().Writeable()) {
        return (AUDIO_ERR_NOEFFECT);
    }

    // only allow this if we haven't read anything yet (i.e. current
    // position is 0).
    if (ReadPosition() != 0.) {
        return (AUDIO_ERR_NOEFFECT);
    }

    if ((err = seekread(GetHeader().Bytes_to_Time(val), setting))
        != AUDIO_SUCCESS) {
        return (err);
    }

    // this should *never* happen 'cause seekread just sets setting
    // to GetHeader().Time_to_Bytes....
    if (setting != val) {
        // don't really know what error is apropos for this.
        return (AUDIO_ERR_BADFRAME);
    }

    offset = val;
    return (AUDIO_SUCCESS);
}

off_t AudioRawPipe::
GetOffset() const
{
    return (offset);
}