ceph/src/common/module.c

   1 /*
   2  * Ceph - scalable distributed file system
   3  *
   4  * Copyright (C) 2014 Inktank Storage, Inc.
   5  *
   6  * This is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License version 2.1, as published by the Free Software
   9  * Foundation.  See file COPYING.
  10  *
  11  */
  12
  13 #include "acconfig.h"
  14 #include "include/compat.h"
  15 #include <errno.h>
  16 #include <stdio.h>
  17 #include <stdlib.h>
  18 #include <string.h>
  19 #if defined(__FreeBSD__)
  20 #include <sys/wait.h>
  21 #endif
  22
  23 /*
  24  * TODO: Switch to libkmod when we abandon older platforms.  The APIs
  25  * we want are:
  26  *
  27  * - kmod_module_new_from_name() for obtaining handles;
  28  * - kmod_module_probe_insert_module() for module_load();
  29  * - kmod_module_get_info(), kmod_module_info_get_{key,value}() for
  30  *   module_has_param().
  31  */
  32
  33 /*
  34  * Return command's exit status or -1 on error.
  35  */
  36 static int run_command(const char *command)
  37 {
  38         int status;
  39
  40         status = system(command);
  41         if (status >= 0 && WIFEXITED(status))
  42                 return WEXITSTATUS(status);
  43
  44         if (status < 0) {
  45                 char error_buf[80];
  46                 char* errp = ceph_strerror_r(errno, error_buf, sizeof(error_buf));
  47                 fprintf(stderr, "couldn't run '%s': %s\n", command,
  48                         errp);
  49         } else if (WIFSIGNALED(status)) {
  50                 fprintf(stderr, "'%s' killed by signal %d\n", command,
  51                         WTERMSIG(status));
  52         } else {
  53                 fprintf(stderr, "weird status from '%s': %d\n", command,
  54                         status);
  55         }
  56
  57         return -1;
  58 }
  59
  60 int module_has_param(const char *module, const char *param)
  61 {
  62         char command[128];
  63
  64         snprintf(command, sizeof(command),
  65                  "/sbin/modinfo -F parm %s | /bin/grep -q ^%s:",
  66                  module, param);
  67
  68         return run_command(command) == 0;
  69 }
  70
  71 int module_load(const char *module, const char *options)
  72 {
  73         char command[128];
  74
  75         snprintf(command, sizeof(command), "/sbin/modprobe %s %s",
  76                  module, (options ? options : ""));
  77
  78         return run_command(command);
  79 }