static int proc_open(FAR struct file *filep, FAR const char *relpath,
                     int oflags, mode_t mode)
{
  FAR struct proc_file_s *procfile;
  FAR const struct proc_node_s *node;
  FAR struct tcb_s *tcb;
  FAR char *ptr;
  irqstate_t flags;
  unsigned long tmp;
  pid_t pid;

  fvdbg("Open '%s'\n", relpath);

  /* PROCFS is read-only.  Any attempt to open with any kind of write
   * access is not permitted.
   *
   * REVISIT:  Write-able proc files could be quite useful.
   */

  if ((oflags & O_WRONLY) != 0 || (oflags & O_RDONLY) == 0)
    {
      fdbg("ERROR: Only O_RDONLY supported\n");
      return -EACCES;
    }

  /* The first segment of the relative path should be a task/thread ID */

  ptr = NULL;
  tmp = strtoul(relpath, &ptr, 10);

  if (!ptr || *ptr != '/')
    {
      fdbg("ERROR: Invalid path \"%s\"\n", relpath);
      return -ENOENT;
    }

  /* Skip over the slash */

  ptr++;

  /* A valid PID would be in the range of 0-32767 (0 is reserved for the
   * IDLE thread).
   */

  if (tmp >= 32768)
    {
      fdbg("ERROR: Invalid PID %ld\n", tmp);
      return -ENOENT;
    }

  /* Now verify that a task with this task/thread ID exists */

  pid = (pid_t)tmp;

  flags = irqsave();
  tcb = sched_gettcb(pid);
  irqrestore(flags);

  if (!tcb)
    {
      fdbg("ERROR: PID %d is no longer valid\n", (int)pid);
      return -ENOENT;
    }

  /* The remaining segments of the relpath should be a well known node in
   * the task/thread tree.
   */

  node = proc_findnode(ptr);
  if (!node)
    {
      fdbg("ERROR: Invalid path \"%s\"\n", relpath);
      return -ENOENT;
    }

  /* The node must be a file, not a directory */

  if (node->dtype != DTYPE_FILE)
    {
      fdbg("ERROR: Path \"%s\" is a directory\n", relpath);
      return -EISDIR;
    }

  /* Allocate a container to hold the task and node selection */

  procfile = (FAR struct proc_file_s *)kzalloc(sizeof(struct proc_file_s));
  if (!procfile)
    {
      fdbg("ERROR: Failed to allocate file container\n");
      return -ENOMEM;
    }

  /* Initialize the file container */

  procfile->pid  = pid;
  procfile->node = node;

  /* Save the index as the open-specific state in filep->f_priv */

  filep->f_priv = (FAR void *)procfile;
  return OK;
}
static int proc_opendir(FAR const char *relpath, FAR struct fs_dirent_s *dir)
{
  FAR struct proc_dir_s *procdir;
  FAR const struct proc_node_s *node;
  FAR struct tcb_s *tcb;
  irqstate_t flags;
  unsigned long tmp;
  FAR char *ptr;
  pid_t pid;

  fvdbg("relpath: \"%s\"\n", relpath ? relpath : "NULL");
  DEBUGASSERT(relpath && dir && !dir->u.procfs);

  /* The relative must be either:
   *
   *  (1) "<pid>" - The sub-directory of task/thread attributes, or
   *  (2) The name of a directory node under <pid>
   */

  /* Otherwise, the relative path should be a valid task/thread ID */

  ptr = NULL;
  tmp = strtoul(relpath, &ptr, 10);

  if (!ptr || (*ptr != '\0' && *ptr != '/'))
    {
      /* strtoul failed or there is something in the path after the pid */

      fdbg("ERROR: Invalid path \"%s\"\n", relpath);
      return -ENOENT;
   }

  /* A valid PID would be in the range of 0-32767 (0 is reserved for the
   * IDLE thread).
   */

  if (tmp >= 32768)
    {
      fdbg("ERROR: Invalid PID %ld\n", tmp);
      return -ENOENT;
    }

  /* Now verify that a task with this task/thread ID exists */

  pid = (pid_t)tmp;

  flags = irqsave();
  tcb = sched_gettcb(pid);
  irqrestore(flags);

  if (!tcb)
    {
      fdbg("ERROR: PID %d is not valid\n", (int)pid);
      return -ENOENT;
    }

  /* Allocate the directory structure.  Note that the index and procentry
   * pointer are implicitly nullified by kzalloc().  Only the remaining,
   * non-zero entries will need be initialized.
   */

  procdir = (FAR struct proc_dir_s *)kzalloc(sizeof(struct proc_dir_s));
  if (!procdir)
    {
      fdbg("ERROR: Failed to allocate the directory structure\n");
      return -ENOMEM;
    }

  /* Was the <pid> the final element of the path? */

  if (*ptr != '\0' && strcmp(ptr, "/") != 0)
    {
      /* There is something in the path after the pid.  Skip over the path
       * segment delimiter and see if we can identify the node of interest.
       */

      ptr++;
      node = proc_findnode(ptr);
      if (!node)
        {
          fdbg("ERROR: Invalid path \"%s\"\n", relpath);
          kfree(procdir);
          return -ENOENT;
        }

      /* The node must be a directory, not a file */

      if (node->dtype != DTYPE_DIRECTORY)
        {
          fdbg("ERROR: Path \"%s\" is not a directory\n", relpath);
          kfree(procdir);
          return -ENOTDIR;
        }

      /* This is a second level directory */

      procdir->base.level    = 2;
      procdir->base.nentries = PROC_NGROUPNODES;
      procdir->node          = node;
    }
  else
    {
      /* Use the special level0 node */

      procdir->base.level    = 1;
      procdir->base.nentries = PROC_NLEVEL0NODES;
      procdir->node          = &g_level0node;
    }

   procdir->pid  = pid;
   dir->u.procfs = (FAR void *)procdir;
   return OK;
}
static int proc_stat(const char *relpath, struct stat *buf)
{
  FAR const struct proc_node_s *node;
  FAR struct tcb_s *tcb;
  unsigned long tmp;
  FAR char *ptr;
  irqstate_t flags;
  pid_t pid;

  /* Two path forms are accepted:
   *
   * "<pid>" - If <pid> refers to a currently active task/thread, then it
   *   is a directory
   * "<pid>/<node>" - If <node> is a recognized node then, then it
   *   is a file or directory.
   */

  ptr = NULL;
  tmp = strtoul(relpath, &ptr, 10);

  if (!ptr)
    {
      fdbg("ERROR: Invalid path \"%s\"\n", relpath);
      return -ENOENT;
   }

  /* A valid PID would be in the range of 0-32767 (0 is reserved for the
   * IDLE thread).
   */

  if (tmp >= 32768)
    {
      fdbg("ERROR: Invalid PID %ld\n", tmp);
      return -ENOENT;
    }

  /* Now verify that a task with this task/thread ID exists */

  pid = (pid_t)tmp;

  flags = irqsave();
  tcb = sched_gettcb(pid);
  irqrestore(flags);

  if (!tcb)
    {
      fdbg("ERROR: PID %d is no longer valid\n", (int)pid);
      return -ENOENT;
    }

  /* Was the <pid> the final element of the path? */

  if (*ptr == '\0' || strcmp(ptr, "/") == 0)
    {
      /* Yes ... It's a read-only directory */

      buf->st_mode = S_IFDIR|S_IROTH|S_IRGRP|S_IRUSR;
    }

  /* Verify that the process ID is followed by valid path segment delimiter */

  else if (*ptr != '/')
    {
      /* We are required to return -ENOENT all all invalid paths */

      fdbg("ERROR: Bad delimiter '%c' in relpath '%s'\n", *ptr, relpath);
      return -ENOENT;
    }
  else
    {
      /* Otherwise, the second segment of the relpath should be a well
       * known node of the task/thread directory structure.
       */

      /* Skip over the path segment delimiter */

      ptr++;

      /* Lookup the well-known node associated with the relative path. */

      node = proc_findnode(ptr);
      if (!node)
        {
          fdbg("ERROR: Invalid path \"%s\"\n", relpath);
          return -ENOENT;
        }

      /* If the node exists, it is the name for a read-only file or
       * directory.
       */

      if (node->dtype == DTYPE_FILE)
        {
          buf->st_mode = S_IFREG|S_IROTH|S_IRGRP|S_IRUSR;
        }
      else
        {
          buf->st_mode = S_IFDIR|S_IROTH|S_IRGRP|S_IRUSR;
        }
    }

  /* File/directory size, access block size */

  buf->st_size    = 0;
  buf->st_blksize = 0;
  buf->st_blocks  = 0;
  return OK;
}
Exemple #4
0
static int proc_open(FAR struct file *filep, FAR const char *relpath,
                     int oflags, mode_t mode)
{
  FAR struct proc_file_s *procfile;
  FAR const struct proc_node_s *node;
  FAR struct tcb_s *tcb;
  FAR char *ptr;
  irqstate_t flags;
  unsigned long tmp;
  pid_t pid;

  finfo("Open '%s'\n", relpath);

  /* PROCFS is read-only.  Any attempt to open with any kind of write
   * access is not permitted.
   *
   * REVISIT:  Write-able proc files could be quite useful.
   */

  if ((oflags & O_WRONLY) != 0 || (oflags & O_RDONLY) == 0)
    {
      ferr("ERROR: Only O_RDONLY supported\n");
      return -EACCES;
    }

  /* The first segment of the relative path should be a task/thread ID or
   * the string "self".
   */

  ptr = NULL;

  if (strncmp(relpath, "self", 4) == 0)
    {
      tmp = (unsigned long)getpid();    /* Get the PID of the calling task */
      ptr = (FAR char *)relpath + 4;    /* Discard const */
    }
  else
    {
      tmp = strtoul(relpath, &ptr, 10); /* Extract the PID from path */
    }

  if (ptr == NULL || *ptr != '/')
    {
      ferr("ERROR: Invalid path \"%s\"\n", relpath);
      return -ENOENT;
    }

  /* Skip over the slash */

  ptr++;

  /* A valid PID would be in the range of 0-32767 (0 is reserved for the
   * IDLE thread).
   */

  if (tmp >= 32768)
    {
      ferr("ERROR: Invalid PID %ld\n", tmp);
      return -ENOENT;
    }

  /* Now verify that a task with this task/thread ID exists */

  pid = (pid_t)tmp;

  flags = enter_critical_section();
  tcb = sched_gettcb(pid);
  leave_critical_section(flags);

  if (tcb == NULL)
    {
      ferr("ERROR: PID %d is no longer valid\n", (int)pid);
      return -ENOENT;
    }

  /* The remaining segments of the relpath should be a well known node in
   * the task/thread tree.
   */

  node = proc_findnode(ptr);
  if (node == NULL)
    {
      ferr("ERROR: Invalid path \"%s\"\n", relpath);
      return -ENOENT;
    }

  /* The node must be a file, not a directory */

  if (!DIRENT_ISFILE(node->dtype))
    {
      ferr("ERROR: Path \"%s\" is not a regular file\n", relpath);
      return -EISDIR;
    }

  /* Allocate a container to hold the task and node selection */

  procfile = (FAR struct proc_file_s *)kmm_zalloc(sizeof(struct proc_file_s));
  if (procfile == NULL)
    {
      ferr("ERROR: Failed to allocate file container\n");
      return -ENOMEM;
    }

  /* Initialize the file container */

  procfile->pid  = pid;
  procfile->node = node;

  /* Save the index as the open-specific state in filep->f_priv */

  filep->f_priv = (FAR void *)procfile;
  return OK;
}