Logo Search packages:      
Sourcecode: libibverbs version File versions  Download package

sysfs.c

/*
 * Copyright (c) 2006 Cisco Systems.  All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - 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.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 * $Id$
 */

#if HAVE_CONFIG_H
#  include <config.h>
#endif /* HAVE_CONFIG_H */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#include "ibverbs.h"

static char *sysfs_path;

const char *ibv_get_sysfs_path(void)
{
      char *env = NULL;

      if (sysfs_path)
            return sysfs_path;

      /*
       * Only follow use path passed in through the calling user's
       * environment if we're not running SUID.
       */
      if (getuid() == geteuid())
            env = getenv("SYSFS_PATH");

      if (env) {
            int len;

            sysfs_path = strndup(env, 256);
            len = strlen(sysfs_path);
            while (len > 0 && sysfs_path[len - 1] == '/') {
                  --len;
                  sysfs_path[len] = '\0';
            }
      } else
            sysfs_path = "/sys";

      return sysfs_path;
}

int ibv_read_sysfs_file(const char *dir, const char *file,
                  char *buf, size_t size)
{
      char *path;
      int fd;
      int len;

      asprintf(&path, "%s/%s", dir, file);

      fd = open(path, O_RDONLY);
      if (fd < 0) {
            free(path);
            return -1;
      }

      len = read(fd, buf, size);

      close(fd);
      free(path);

      if (len > 0 && buf[len - 1] == '\n')
            buf[--len] = '\0';

      return len;
}

Generated by  Doxygen 1.6.0   Back to index