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 #ifndef _WIN32
  24 /*
  25  * TODO: Switch to libkmod when we abandon older platforms.  The APIs
  26  * we want are:
  27  *
  28  * - kmod_module_new_from_name() for obtaining handles;
  29  * - kmod_module_probe_insert_module() for module_load();
  30  * - kmod_module_get_info(), kmod_module_info_get_{key,value}() for
  31  *   module_has_param().
  32  */
  33
  34 /*
  35  * Return command's exit status or -1 on error.
  36  */
  37 static int run_command(const char *command)
  38 {
  39         int status;
  40
  41         status = system(command);
  42         if (status >= 0 && WIFEXITED(status))
  43                 return WEXITSTATUS(status);
  44
  45         if (status < 0) {
  46                 char error_buf[80];
  47                 char* errp = ceph_strerror_r(errno, error_buf, sizeof(error_buf));
  48                 fprintf(stderr, "couldn't run '%s': %s\n", command,
  49                         errp);
  50         } else if (WIFSIGNALED(status)) {
  51                 fprintf(stderr, "'%s' killed by signal %d\n", command,
  52                         WTERMSIG(status));
  53         } else {
  54                 fprintf(stderr, "weird status from '%s': %d\n", command,
  55                         status);
  56         }
  57
  58         return -1;
  59 }
  60
  61 int module_has_param(const char *module, const char *param)
  62 {
  63         char command[128];
  64
  65         snprintf(command, sizeof(command),
  66                  "/sbin/modinfo -F parm %s | /bin/grep -q ^%s:",
  67                  module, param);
  68
  69         return run_command(command) == 0;
  70 }
  71
  72 int module_load(const char *module, const char *options)
  73 {
  74         char command[128];
  75
  76         snprintf(command, sizeof(command), "/sbin/modprobe %s %s",
  77                  module, (options ? options : ""));
  78
  79         return run_command(command);
  80 }
  81
  82 #else
  83
  84 // We're stubbing out those functions, for now.
  85 int module_has_param(const char *module, const char *param)
  86 {
  87         return -1;
  88 }
  89
  90 int module_load(const char *module, const char *options)
  91 {
  92         return -1;
  93 }
  94
  95 #endif /* _WIN32 */