src/DiskIO/Blocking/BlockingFile.cc

   1 /*
   2  * DEBUG: section 47    Store Directory Routines
   3  * AUTHOR: Robert Collins
   4  *
   5  * SQUID Web Proxy Cache          http://www.squid-cache.org/
   6  * ----------------------------------------------------------
   7  *
   8  *  Squid is the result of efforts by numerous individuals from
   9  *  the Internet community; see the CONTRIBUTORS file for full
  10  *  details.   Many organizations have provided support for Squid's
  11  *  development; see the SPONSORS file for full details.  Squid is
  12  *  Copyrighted (C) 2001 by the Regents of the University of
  13  *  California; see the COPYRIGHT file for full details.  Squid
  14  *  incorporates software developed and/or copyrighted by other
  15  *  sources; see the CREDITS file for full details.
  16  *
  17  *  This program is free software; you can redistribute it and/or modify
  18  *  it under the terms of the GNU General Public License as published by
  19  *  the Free Software Foundation; either version 2 of the License, or
  20  *  (at your option) any later version.
  21  *
  22  *  This program is distributed in the hope that it will be useful,
  23  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  24  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  25  *  GNU General Public License for more details.
  26  *
  27  *  You should have received a copy of the GNU General Public License
  28  *  along with this program; if not, write to the Free Software
  29  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  30  *
  31  * Copyright (c) 2003, Robert Collins <robertc@squid-cache.org>
  32  */
  33 #include "squid.h"
  34 #include "BlockingFile.h"
  35 #include "Debug.h"
  36 #include "defines.h"
  37 #include "disk.h"
  38 #include "DiskIO/IORequestor.h"
  39 #include "DiskIO/ReadRequest.h"
  40 #include "DiskIO/WriteRequest.h"
  41 #include "globals.h"
  42
  43 #if HAVE_ERRNO_H
  44 #include <errno.h>
  45 #endif
  46
  47 CBDATA_CLASS_INIT(BlockingFile);
  48
  49 BlockingFile::BlockingFile(char const *aPath) : fd (-1), closed (true), error_(false)
  50 {
  51     assert(aPath);
  52     debugs(79, 3, "BlockingFile::BlockingFile: " << aPath);
  53     path_ = xstrdup (aPath);
  54 }
  55
  56 BlockingFile::~BlockingFile()
  57 {
  58     safe_free (path_);
  59     doClose();
  60 }
  61
  62 void
  63 BlockingFile::open(int flags, mode_t mode, RefCount<IORequestor> callback)
  64 {
  65     /* Simulate async calls */
  66     fd = file_open(path_ , flags);
  67     ioRequestor = callback;
  68
  69     if (fd < 0) {
  70         debugs(79, 3, "BlockingFile::open: got failure (" << errno << ")");
  71         error(true);
  72     } else {
  73         closed = false;
  74         ++store_open_disk_fd;
  75         debugs(79, 3, "BlockingFile::open: opened FD " << fd);
  76     }
  77
  78     callback->ioCompletedNotification();
  79 }
  80
  81 /**
  82  * Alias for BlockingFile::open(...)
  83  \copydoc BlockingFile::open(int flags, mode_t mode, RefCount<IORequestor> callback)
  84  */
  85 void
  86 BlockingFile::create(int flags, mode_t mode, RefCount<IORequestor> callback)
  87 {
  88     /* We use the same logic path for open */
  89     open(flags, mode, callback);
  90 }
  91
  92 void BlockingFile::doClose()
  93 {
  94     if (fd > -1) {
  95         closed = true;
  96         file_close(fd);
  97         --store_open_disk_fd;
  98         fd = -1;
  99     }
 100 }
 101
 102 void
 103 BlockingFile::close()
 104 {
 105     debugs(79, 3, "BlockingFile::close: " << this << " closing for " << ioRequestor.getRaw());
 106     doClose();
 107     assert (ioRequestor.getRaw());
 108     ioRequestor->closeCompleted();
 109 }
 110
 111 bool
 112 BlockingFile::canRead() const
 113 {
 114     return fd > -1;
 115 }
 116
 117 bool
 118 BlockingFile::error() const
 119 {
 120     if ((fd < 0 && !closed) || error_)
 121         return true;
 122
 123     return false;
 124 }
 125
 126 void BlockingFile::error(bool const &aBool)
 127 {
 128     error_ = aBool;
 129 }
 130
 131 void
 132 BlockingFile::read(ReadRequest *aRequest)
 133 {
 134     assert (fd > -1);
 135     assert (ioRequestor.getRaw());
 136     readRequest = aRequest;
 137     debugs(79, 3, HERE << aRequest->len << " for FD " << fd << " at " << aRequest->offset);
 138     file_read(fd, aRequest->buf, aRequest->len, aRequest->offset, ReadDone, this);
 139 }
 140
 141 void
 142 BlockingFile::ReadDone(int fd, const char *buf, int len, int errflag, void *my_data)
 143 {
 144     BlockingFile *myFile = static_cast<BlockingFile *>(my_data);
 145     assert (myFile);
 146     myFile->readDone (fd, buf, len, errflag);
 147 }
 148
 149 void
 150 BlockingFile::write(WriteRequest *aRequest)
 151 {
 152     debugs(79, 3, HERE << aRequest->len << " for FD " << fd << " at " << aRequest->offset);
 153     writeRequest = aRequest;
 154     file_write(fd,
 155                aRequest->offset,
 156                (char *)aRequest->buf,
 157                aRequest->len,
 158                WriteDone,
 159                this,
 160                aRequest->free_func);
 161 }
 162
 163 bool
 164 BlockingFile::ioInProgress() const
 165 {
 166     /** \retval false   IO is never pending with UFS */
 167     return false;
 168 }
 169
 170 /*  === STATIC =========================================================== */
 171
 172 void
 173 BlockingFile::readDone(int rvfd, const char *buf, int len, int errflag)
 174 {
 175     debugs(79, 3, "BlockingFile::readDone: FD " << rvfd);
 176     assert (fd == rvfd);
 177
 178     ssize_t rlen;
 179
 180     if (errflag) {
 181         debugs(79, 3, "BlockingFile::readDone: got failure (" << errflag << ")");
 182         rlen = -1;
 183     } else {
 184         rlen = (ssize_t) len;
 185     }
 186
 187     if (errflag == DISK_EOF)
 188         errflag = DISK_OK;      /* EOF is signalled by len == 0, not errors... */
 189
 190     ReadRequest::Pointer result = readRequest;
 191
 192     readRequest = NULL;
 193
 194     ioRequestor->readCompleted(buf, rlen, errflag, result);
 195 }
 196
 197 void
 198 BlockingFile::WriteDone (int fd, int errflag, size_t len, void *me)
 199 {
 200     BlockingFile *aFile = static_cast<BlockingFile *>(me);
 201     aFile->writeDone (fd, errflag, len);
 202 }
 203
 204 void
 205 BlockingFile::writeDone(int rvfd, int errflag, size_t len)
 206 {
 207     assert (rvfd == fd);
 208     debugs(79, 3, HERE << "FD " << fd << ", len " << len);
 209
 210     WriteRequest::Pointer result = writeRequest;
 211     writeRequest = NULL;
 212
 213     if (errflag) {
 214         debugs(79, DBG_CRITICAL, "storeUfsWriteDone: got failure (" << errflag << ")");
 215         doClose();
 216         ioRequestor->writeCompleted (DISK_ERROR,0, result);
 217         return;
 218     }
 219
 220     ioRequestor->writeCompleted(DISK_OK, len, result);
 221 }
 222