src/add-ons/kernel/file_systems/bindfs/Volume.cpp

   1 /*
   2  * Copyright 2011, Oliver Tappe <zooey@hirschkaefer.de>
   3  * Distributed under the terms of the MIT License.
   4  */
   5
   6
   7 #include "Volume.h"
   8
   9 #include <dirent.h>
  10 #include <errno.h>
  11 #include <fcntl.h>
  12 #include <string.h>
  13 #include <sys/stat.h>
  14
  15 #include <new>
  16
  17 #include <driver_settings.h>
  18 #include <KernelExport.h>
  19 #include <vfs.h>
  20
  21 #include <AutoDeleter.h>
  22
  23 #include "DebugSupport.h"
  24 #include "kernel_interface.h"
  25 #include "Node.h"
  26 #include "Utils.h"
  27
  28
  29 // #pragma mark - Volume
  30
  31
  32 Volume::Volume(fs_volume* fsVolume)
  33         :
  34         fFSVolume(fsVolume),
  35         fSourceFSVolume(NULL),
  36         fSourceVnode(NULL),
  37         fRootNode(NULL)
  38 {
  39 }
  40
  41
  42 Volume::~Volume()
  43 {
  44         if (fSourceVnode != NULL)
  45                 vfs_put_vnode(fSourceVnode);
  46 }
  47
  48
  49 status_t
  50 Volume::Mount(const char* parameterString)
  51 {
  52         const char* source = NULL;
  53         void* parameterHandle = parse_driver_settings_string(parameterString);
  54         CObjectDeleter<void, status_t> parameterDeleter(parameterHandle,
  55                 delete_driver_settings);
  56         if (parameterHandle != NULL)
  57                 source = get_driver_parameter(parameterHandle, "source", NULL, NULL);
  58         if (source == NULL || source[0] == '\0') {
  59                 ERROR("need source folder ('source' parameter)!\n");
  60                 RETURN_ERROR(B_BAD_VALUE);
  61         }
  62
  63         status_t error = vfs_get_vnode_from_path(source, true, &fSourceVnode);
  64         if (error != B_OK)
  65                 RETURN_ERROR(error);
  66         if (fSourceVnode == NULL)
  67                 RETURN_ERROR(B_ENTRY_NOT_FOUND);
  68         fs_vnode* sourceFSNode = vfs_fsnode_for_vnode(fSourceVnode);
  69         fSourceFSVolume = volume_for_vnode(sourceFSNode);
  70
  71         struct stat st;
  72         if ((stat(source, &st)) != 0)
  73                 RETURN_ERROR(B_ERROR);
  74
  75         strlcpy(fName, "bindfs:", sizeof(fName));
  76         strlcpy(fName, source, sizeof(fName));
  77
  78         // create the root node
  79         fRootNode = new(std::nothrow) Node(st.st_ino, st.st_mode);
  80         if (fRootNode == NULL)
  81                 RETURN_ERROR(B_NO_MEMORY);
  82
  83         _InitVnodeOpsFrom(sourceFSNode);
  84
  85         // publish the root node
  86         error = publish_vnode(fFSVolume, fRootNode->ID(), fRootNode, &fVnodeOps,
  87                 fRootNode->Mode() & S_IFMT, 0);
  88         if (error != B_OK) {
  89                 delete fRootNode;
  90                 fRootNode = NULL;
  91                 return error;
  92         }
  93
  94         return B_OK;
  95 }
  96
  97
  98 void
  99 Volume::Unmount()
 100 {
 101 }
 102
 103
 104 status_t
 105 Volume::_InitVnodeOpsFrom(fs_vnode* sourceNode)
 106 {
 107         // vnode ops
 108         int opsCount = sizeof(fVnodeOps) / sizeof(void*);
 109         for (int i = 0; i < opsCount; ++i) {
 110                 if (((void**)sourceNode->ops)[i] == NULL)
 111                         ((void**)&fVnodeOps)[i] = NULL;
 112                 else
 113                         ((void**)&fVnodeOps)[i] = ((void**)&gBindFSVnodeOps)[i];
 114         }
 115
 116         return B_OK;
 117 }