src/kits/storage/FdIO.cpp

   1 /*
   2  * Copyright 2014, Ingo Weinhold, ingo_weinhold@gmx.de.
   3  * Distributed under the terms of the MIT License.
   4  */
   5
   6
   7 #include <FdIO.h>
   8
   9 #include <errno.h>
  10 #include <fcntl.h>
  11 #include <unistd.h>
  12
  13
  14 BFdIO::BFdIO()
  15         :
  16         BPositionIO(),
  17         fFd(-1),
  18         fOwnsFd(false)
  19 {
  20 }
  21
  22
  23 BFdIO::BFdIO(int fd, bool keepFd)
  24         :
  25         BPositionIO(),
  26         fFd(fd),
  27         fOwnsFd(keepFd)
  28 {
  29 }
  30
  31
  32 BFdIO::~BFdIO()
  33 {
  34         Unset();
  35 }
  36
  37
  38 void
  39 BFdIO::SetTo(int fd, bool keepFd)
  40 {
  41         Unset();
  42
  43         fFd = fd;
  44         fOwnsFd = keepFd;
  45 }
  46
  47
  48 void
  49 BFdIO::Unset()
  50 {
  51         if (fOwnsFd && fFd >= 0)
  52                 close(fFd);
  53
  54         fFd = -1;
  55         fOwnsFd = false;
  56 }
  57
  58
  59 ssize_t
  60 BFdIO::Read(void* buffer, size_t size)
  61 {
  62         ssize_t bytesRead = read(fFd, buffer, size);
  63         return bytesRead >= 0 ? bytesRead : errno;
  64 }
  65
  66
  67 ssize_t
  68 BFdIO::Write(const void* buffer, size_t size)
  69 {
  70         ssize_t bytesWritten = write(fFd, buffer, size);
  71         return bytesWritten >= 0 ? bytesWritten : errno;
  72 }
  73
  74
  75 ssize_t
  76 BFdIO::ReadAt(off_t position, void* buffer, size_t size)
  77 {
  78         ssize_t bytesRead = pread(fFd, buffer, size, position);
  79         return bytesRead >= 0 ? bytesRead : errno;
  80 }
  81
  82
  83 ssize_t
  84 BFdIO::WriteAt(off_t position, const void* buffer, size_t size)
  85 {
  86         ssize_t bytesWritten = pwrite(fFd, buffer, size, position);
  87         return bytesWritten >= 0 ? bytesWritten : errno;
  88 }
  89
  90
  91 off_t
  92 BFdIO::Seek(off_t position, uint32 seekMode)
  93 {
  94         off_t newPosition = lseek(fFd, position, seekMode);
  95         return newPosition >= 0 ? newPosition : errno;
  96 }
  97
  98
  99 off_t
 100 BFdIO::Position() const
 101 {
 102         return const_cast<BFdIO*>(this)->BFdIO::Seek(0, SEEK_CUR);
 103 }
 104
 105
 106 status_t
 107 BFdIO::SetSize(off_t size)
 108 {
 109         return ftruncate(fFd, size) == 0 ? B_OK : errno;
 110 }
 111
 112
 113 status_t
 114 BFdIO::GetSize(off_t* _size) const
 115 {
 116         struct stat st;
 117         if (fstat(fFd, &st) != 0)
 118                 return errno;
 119
 120         *_size = st.st_size;
 121         return B_OK;
 122 }