summaryrefslogtreecommitdiff
path: root/nuttx/fs/fs_open.c
blob: 0fc1b5133c35a0597de0de83f321b9406e04041e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
/************************************************************
 * fs_open.c
 *
 *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name Gregory Nutt nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ************************************************************/

/************************************************************
 * Included Files
 ************************************************************/

#include <nuttx/config.h>
#include <sys/types.h>
#include <fcntl.h>
#include <sched.h>
#include <errno.h>
#ifdef CONFIG_FILE_MODE
#include <stdarg.h>
#endif
#include <nuttx/fs.h>
#include "fs_internal.h"

/************************************************************
 * Private Functions
 ************************************************************/

/************************************************************
 * Public Functions
 ************************************************************/

#if CONFIG_NFILE_DESCRIPTORS > 0

int inode_checkflags(FAR struct inode *inode, int oflags)
{
  if (((oflags & O_RDOK) != 0 && !inode->u.i_ops->read) ||
      ((oflags & O_WROK) != 0 && !inode->u.i_ops->write))
    {
      *get_errno_ptr() = EACCES;
      return ERROR;
    }
  else
    {
      return OK;
    }
}

int open(const char *path, int oflags, ...)
{
  struct filelist *list;
  FAR struct inode *inode;
  int status;
  int fd;

  /* Get the thread-specific file list */

  list = sched_getfiles();
  if (!list)
    {
      *get_errno_ptr() = EMFILE;
      return ERROR;
    }

#ifdef CONFIG_FILE_MODE
# warning "File creation not implemented"
  mode_t mode = 0;

  /* If the file is opened for creation, then get the mode bits */

  if (oflags & (O_WRONLY|O_CREAT) != 0)
    {
      va_list ap;
      va_start(ap, oflags);
      mode = va_arg(ap, mode_t);
      va_end(ap);
    }
#endif

  /* Get an inode for this file */

  const char *relpath = NULL;
  inode = inode_find(path, &relpath);
  if (!inode)
    {
      /* "O_CREAT is not set and the named file does not exist.  Or,
       *  a directory component in pathname does not exist or is a
       *  dangling symbolic link."
       */

      *get_errno_ptr() = ENOENT;
      return ERROR;
    }

  /* Verify that the inode is either a "normal" or a mountpoint.  We
   * specifically exclude block drivers.
   */

  if (!INODE_IS_DRIVER(inode) && !INODE_IS_MOUNTPT(inode))
    {
      *get_errno_ptr() = ENXIO;
      return ERROR;
    }

  /* Make sure that the inode supports the requested access */

  if (inode_checkflags(inode, oflags) != OK)
    {
      inode_release(inode);
      return ERROR;
    }

  /* Associate the inode with a file structure */

  fd = files_allocate(inode, oflags, 0);
  if (fd < 0)
    {
      inode_release(inode);
      *get_errno_ptr() = EMFILE;
      return ERROR;
    }

  /* Perform the driver open operation */

  status = OK;
  if (inode->u.i_ops && inode->u.i_ops->open)
    {
      if (INODE_IS_MOUNTPT(inode))
        {
          status = inode->u.i_ops->open((FAR struct file*)&list->fl_files[fd]);
        }
      else
        {
          status = inode->u.i_mops->open((FAR struct file*)&list->fl_files[fd], relpath);
        }
    }

  if (status != OK || !inode->u.i_ops)
    {
      files_release(fd);
      inode_release(inode);
      *get_errno_ptr() = ENODEV;
      return ERROR;
    }

  return fd;
}

#endif /* CONFIG_NFILE_DESCRIPTORS */