src/modules-load.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 2 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <unistd.h>
  23 #include <fcntl.h>
  24 #include <errno.h>
  25 #include <string.h>
  26 #include <sys/stat.h>
  27 #include <limits.h>
  28 #include <dirent.h>
  29
  30 #include "log.h"
  31 #include "util.h"
  32 #include "strv.h"
  33
  34 /* This reads all module names listed in /etc/modules-load.d/?*.conf and
  35  * loads them into the kernel. This follows roughly Debian's way to
  36  * handle modules, but uses a directory of fragments instead of a
  37  * single /etc/modules file. */
  38
  39 static int scandir_filter(const struct dirent *d) {
  40         assert(d);
  41
  42         if (ignore_file(d->d_name))
  43                 return 0;
  44
  45         if (d->d_type != DT_REG &&
  46             d->d_type != DT_LNK &&
  47             d->d_type != DT_UNKNOWN)
  48                 return 0;
  49
  50         return endswith(d->d_name, ".conf");
  51 }
  52
  53 int main(int argc, char *argv[]) {
  54         struct dirent **de = NULL;
  55         int r = EXIT_FAILURE, n, i;
  56         char **arguments = NULL;
  57         unsigned n_arguments = 0, n_allocated = 0;
  58
  59         if (argc > 1) {
  60                 log_error("This program takes no argument.");
  61                 return EXIT_FAILURE;
  62         }
  63
  64         log_set_target(LOG_TARGET_SYSLOG_OR_KMSG);
  65         log_parse_environment();
  66         log_open();
  67
  68         if (!(arguments = strv_new("/sbin/modprobe", "-sab", "--", NULL))) {
  69                 log_error("Failed to allocate string array");
  70                 goto finish;
  71         }
  72
  73         n_arguments = n_allocated = 3;
  74
  75         if ((n = scandir("/etc/modules-load.d/", &de, scandir_filter, alphasort)) < 0) {
  76
  77                 if (errno == ENOENT)
  78                         r = EXIT_SUCCESS;
  79                 else
  80                         log_error("Failed to enumerate /etc/modules-load.d/ files: %m");
  81
  82                 goto finish;
  83         }
  84
  85         r = EXIT_SUCCESS;
  86
  87         for (i = 0; i < n; i++) {
  88                 int k;
  89                 char *fn;
  90                 FILE *f;
  91
  92                 k = asprintf(&fn, "/etc/modules-load.d/%s", de[i]->d_name);
  93                 free(de[i]);
  94
  95                 if (k < 0) {
  96                         log_error("Failed to allocate file name.");
  97                         r = EXIT_FAILURE;
  98                         continue;
  99                 }
 100
 101                 f = fopen(fn, "re");
 102
 103                 if (!f) {
 104                         if (errno == ENOENT) {
 105                                 free(fn);
 106                                 continue;
 107                         }
 108
 109                         log_error("Failed to open %s: %m", fn);
 110                         free(fn);
 111                         r = EXIT_FAILURE;
 112                         continue;
 113                 }
 114
 115                 free(fn);
 116
 117                 for (;;) {
 118                         char line[LINE_MAX], *l, *t;
 119
 120                         if (!(fgets(line, sizeof(line), f)))
 121                                 break;
 122
 123                         l = strstrip(line);
 124                         if (*l == '#' || *l == 0)
 125                                 continue;
 126
 127                         if (!(t = strdup(l))) {
 128                                 log_error("Failed to allocate module name.");
 129                                 continue;
 130                         }
 131
 132                         if (n_arguments >= n_allocated) {
 133                                 char **a;
 134                                 unsigned m;
 135
 136                                 m = MAX(16U, n_arguments*2);
 137
 138                                 if (!(a = realloc(arguments, sizeof(char*) * (m+1)))) {
 139                                         log_error("Failed to increase module array size.");
 140                                         free(t);
 141                                         r = EXIT_FAILURE;
 142                                         continue;
 143                                 }
 144
 145                                 arguments = a;
 146                                 n_allocated = m;
 147                         }
 148
 149                         arguments[n_arguments++] = t;
 150                 }
 151
 152                 if (ferror(f)) {
 153                         r = EXIT_FAILURE;
 154                         log_error("Failed to read from file: %m");
 155                 }
 156
 157                 fclose(f);
 158         }
 159
 160         free(de);
 161
 162 finish:
 163
 164         if (n_arguments > 3) {
 165                 arguments[n_arguments] = NULL;
 166                 execv("/sbin/modprobe", arguments);
 167
 168                 log_error("Failed to execute /sbin/modprobe: %m");
 169                 r = EXIT_FAILURE;
 170         }
 171
 172         strv_free(arguments);
 173
 174         return r;
 175 }