src/system/boot/loader/file_systems/fat/File.cpp

   1 /*
   2  * Copyright 2003-2013, Axel Dörfler, axeld@pinc-software.de.
   3  * Copyright 2008, François Revol <revol@free.fr>
   4  * Distributed under the terms of the MIT License.
   5  */
   6
   7
   8 #include "File.h"
   9
  10 #include <sys/stat.h>
  11 #include <unistd.h>
  12
  13 #include "Directory.h"
  14
  15
  16 //#define TRACE(x) dprintf x
  17 #define TRACE(x) do {} while (0)
  18
  19
  20 namespace FATFS {
  21
  22
  23 File::File(Volume &volume, off_t dirEntryOffset, uint32 cluster, off_t size,
  24         const char *name)
  25         :
  26         fVolume(volume),
  27         fStream(volume, cluster, size, name),
  28         fDirEntryOffset(dirEntryOffset)
  29 {
  30         TRACE(("FATFS::File::()\n"));
  31 }
  32
  33
  34 File::~File()
  35 {
  36         TRACE(("FATFS::File::~()\n"));
  37 }
  38
  39
  40 status_t
  41 File::InitCheck()
  42 {
  43         if (fStream.InitCheck() != B_OK)
  44                 return fStream.InitCheck();
  45
  46         return B_OK;
  47 }
  48
  49
  50 status_t
  51 File::Open(void **_cookie, int mode)
  52 {
  53         TRACE(("FATFS::File::%s(, %d)\n", __FUNCTION__, mode));
  54         if (fStream.InitCheck() < B_OK)
  55                 return fStream.InitCheck();
  56
  57         return Node::Open(_cookie, mode);
  58 }
  59
  60
  61 status_t
  62 File::Close(void *cookie)
  63 {
  64         return Node::Close(cookie);
  65 }
  66
  67
  68 ssize_t
  69 File::ReadAt(void *cookie, off_t pos, void *buffer, size_t bufferSize)
  70 {
  71         TRACE(("FATFS::File::%s(, %Ld,, %d)\n", __FUNCTION__, pos, bufferSize));
  72         status_t err;
  73         err = fStream.ReadAt(pos, buffer, &bufferSize);
  74         if (err < B_OK)
  75                 return err;
  76         return bufferSize;
  77 }
  78
  79
  80 ssize_t
  81 File::WriteAt(void *cookie, off_t pos, const void *buffer, size_t bufferSize)
  82 {
  83         off_t streamSize = fStream.Size();
  84         uint32 firstCluster = fStream.FirstCluster();
  85
  86         // write data
  87         size_t written = bufferSize;
  88         status_t error = fStream.WriteAt(pos, buffer, &written);
  89         if (error != B_OK)
  90                 return error;
  91
  92         // If the file size has changed, we need to adjust the directory entry.
  93         if (fStream.Size() > streamSize || fStream.FirstCluster() != firstCluster) {
  94                 error = Directory::UpdateDirEntry(fVolume, fDirEntryOffset,
  95                         fStream.FirstCluster(), fStream.Size());
  96                 if (error != B_OK)
  97                         return error;
  98                         // TODO: Undo the changes!
  99         }
 100
 101         return written;
 102 }
 103
 104
 105 status_t
 106 File::GetName(char *nameBuffer, size_t bufferSize) const
 107 {
 108         return fStream.GetName(nameBuffer, bufferSize);
 109 }
 110
 111
 112 status_t
 113 File::GetFileMap(struct file_map_run *runs, int32 *count)
 114 {
 115         return fStream.GetFileMap(runs, count);
 116 }
 117
 118
 119 int32
 120 File::Type() const
 121 {
 122         return S_IFREG;
 123 }
 124
 125
 126 off_t
 127 File::Size() const
 128 {
 129         return fStream.Size();
 130 }
 131
 132
 133 ino_t
 134 File::Inode() const
 135 {
 136         return fStream.FirstCluster() << 16;
 137 }
 138
 139
 140 }       // namespace FATFS