usr/src/cmd/audio/utilities/AudioPipe.cc

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
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  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 1990-2001 by Sun Microsystems, Inc.
  24  * All rights reserved.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 #include <stdlib.h>
  30 #include <unistd.h>
  31 #include <AudioPipe.h>
  32
  33 // class AudioPipe methods
  34
  35
  36 // Constructor with file descriptor, mode, and optional name
  37 AudioPipe::
  38 AudioPipe(
  39         const int               desc,           // file descriptor
  40         const FileAccess        acc,            // access mode
  41         const char              *name_local):   // name
  42         AudioUnixfile(name_local, acc)
  43 {
  44         setfd(desc);
  45 }
  46
  47 // The create routine for pipes writes a file header
  48 AudioError AudioPipe::
  49 Create()
  50 {
  51         AudioError      err;
  52
  53         // Was the header properly set?
  54         err = GetHeader().Validate();
  55         if (err != AUDIO_SUCCESS)
  56                 return (RaiseError(err));
  57
  58         // Open fd supplied by constructor
  59         if (!isfdset())
  60                 return (RaiseError(AUDIO_ERR_NOEFFECT));
  61
  62         // Write the file header with current (usually unknown) size
  63         err = encode_filehdr();
  64         if (err != AUDIO_SUCCESS) {
  65                 (void) close(getfd());          // If error, remove file
  66                 setfd(-1);
  67                 return (err);
  68         }
  69
  70         // Set the actual output length to zero
  71         setlength(0.);
  72
  73         return (AUDIO_SUCCESS);
  74 }
  75
  76 // The open routine for pipes decodes the header
  77 AudioError AudioPipe::
  78 Open()
  79 {
  80         AudioError              err;
  81
  82         // The constructor should have supplied a valid fd
  83         if (!isfdset())
  84                 return (RaiseError(AUDIO_ERR_NOEFFECT));
  85
  86         // Decode a file header
  87         err = decode_filehdr();
  88         if (err != AUDIO_SUCCESS) {
  89                 (void) close(getfd());
  90                 setfd(-1);
  91                 return (err);
  92         }
  93
  94         return (AUDIO_SUCCESS);
  95 }
  96
  97 // Read data from underlying pipe into specified buffer.
  98 // No data format translation takes place.
  99 // Since there's no going back, the object's read position pointer is updated.
 100 AudioError AudioPipe::
 101 ReadData(
 102         void*           buf,            // destination buffer address
 103         size_t&         len,            // buffer length (updated)
 104         Double&         pos)            // start position (updated)
 105 {
 106         AudioError      err;
 107         char            *tbuf;          // current buffer pointer
 108         size_t          remain;         // number of bytes remaining
 109         size_t          cnt;            // accumulated number of bytes read
 110
 111         tbuf = (char *)buf;
 112         remain = len;
 113         cnt = 0;
 114
 115         // Pipes return short reads.  If non-blocking i/o, try to read all.
 116         do {
 117                 // Call the real routine
 118                 err = AudioUnixfile::ReadData((void*)tbuf, remain, pos);
 119
 120                 // Update the object's read position
 121                 if (!err) {
 122                         (void) SetReadPosition(pos, Absolute);
 123                         if (remain == 0)
 124                                 break;
 125                         cnt += remain;
 126                         tbuf += remain;
 127                         remain = len - cnt;
 128                 }
 129         } while (!err && (remain > 0) && GetBlocking());
 130         len = cnt;
 131         if (len > 0)
 132                 return (AUDIO_SUCCESS);
 133         return (err);
 134 }
 135
 136 // Write data to underlying file from specified buffer.
 137 // No data format translation takes place.
 138 // Since there's no going back, the object's write position pointer is updated.
 139 AudioError AudioPipe::
 140 WriteData(
 141         void*           buf,            // source buffer address
 142         size_t&         len,            // buffer length (updated)
 143         Double&         pos)            // start position (updated)
 144 {
 145         AudioError      err;
 146
 147         // Call the real routine
 148         err = AudioUnixfile::WriteData(buf, len, pos);
 149
 150         // Update the object's write position
 151         if (err == AUDIO_SUCCESS)
 152                 (void) SetWritePosition(pos, Absolute);
 153         return (err);
 154 }