libkmod/libkmod-config.c

   1 /*
   2  * libkmod - interface to kernel module operations
   3  *
   4  * Copyright (C) 2011  ProFUSION embedded systems
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation version 2.1.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  18  */
  19
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <stddef.h>
  23 #include <stdarg.h>
  24 #include <unistd.h>
  25 #include <errno.h>
  26 #include <string.h>
  27 #include <ctype.h>
  28 #include <sys/stat.h>
  29 #include <sys/types.h>
  30 #include <dirent.h>
  31
  32 #include "libkmod.h"
  33 #include "libkmod-private.h"
  34
  35 static const char *config_files[] = {
  36         "/run/modprobe.d",
  37         "/etc/modprobe.d",
  38         "/usr/local/lib/modprobe",
  39         "/lib/modprobe.d",
  40 };
  41
  42 struct kmod_alias {
  43         char *name;
  44         char *modname;
  45 };
  46
  47 const char *kmod_alias_get_name(const struct kmod_list *l) {
  48         struct kmod_alias *alias = l->data;
  49         return alias->name;
  50 }
  51
  52 const char *kmod_alias_get_modname(const struct kmod_list *l) {
  53         struct kmod_alias *alias = l->data;
  54         return alias->modname;
  55 }
  56
  57 static struct kmod_list *add_alias(struct kmod_ctx *ctx,
  58                                         struct kmod_list *aliases,
  59                                         const char *name, const char *modname)
  60 {
  61         struct kmod_alias *alias;
  62
  63         DBG(ctx, "name=%s modname=%s\n", name, modname);
  64
  65         alias = malloc(sizeof(*alias));
  66         alias->name = strdup(name);
  67         alias->modname = strdup(modname);
  68
  69         return kmod_list_append(aliases, alias);
  70 }
  71
  72 static struct kmod_list *free_alias(struct kmod_ctx *ctx, struct kmod_list *l)
  73 {
  74         struct kmod_alias *alias = l->data;
  75
  76         free(alias->modname);
  77         free(alias->name);
  78         free(alias);
  79
  80         return kmod_list_remove(l);
  81 }
  82
  83 static struct kmod_list *add_blacklist(struct kmod_ctx *ctx,
  84                                         struct kmod_list *blacklist,
  85                                         const char *modname)
  86 {
  87         char *p;
  88
  89         DBG(ctx, "modname=%s\n", modname);
  90
  91         p = strdup(modname);
  92
  93         return kmod_list_append(blacklist, p);
  94 }
  95
  96 static struct kmod_list *free_blacklist(struct kmod_ctx *ctx,
  97                                                         struct kmod_list *l)
  98 {
  99         free(l->data);
 100         return kmod_list_remove(l);
 101 }
 102
 103
 104 int kmod_parse_config_file(struct kmod_ctx *ctx, const char *filename,
 105                                                 struct kmod_config *config)
 106 {
 107         char *line;
 108         FILE *fp;
 109         unsigned int linenum;
 110
 111         DBG(ctx, "%s\n", filename);
 112
 113         fp = fopen(filename, "r");
 114         if (fp == NULL)
 115                 return errno;
 116
 117         while ((line = getline_wrapped(fp, &linenum)) != NULL) {
 118                 char *cmd, *saveptr;
 119
 120                 if (line[0] == '\0' || line[0] == '#')
 121                         goto done_next;
 122
 123                 cmd = strtok_r(line, "\t ", &saveptr);
 124                 if (cmd == NULL)
 125                         goto done_next;
 126
 127                 if (!strcmp(cmd, "alias")) {
 128                         char *alias = strtok_r(NULL, "\t ", &saveptr);
 129                         char *modname = strtok_r(NULL, "\t ", &saveptr);
 130
 131                         if (alias == NULL || modname == NULL)
 132                                 goto syntax_error;
 133
 134                         config->aliases = add_alias(ctx, config->aliases,
 135                                                 underscores(ctx, alias),
 136                                                 underscores(ctx, modname));
 137                 } else if (!strcmp(cmd, "blacklist")) {
 138                         char *modname = strtok_r(NULL, "\t ", &saveptr);
 139
 140                         if (modname == NULL)
 141                                 goto syntax_error;
 142
 143                         config->blacklists = add_blacklist(ctx,
 144                                                 config->blacklists,
 145                                                 underscores(ctx, modname));
 146                 } else if (!strcmp(cmd, "include") || !strcmp(cmd, "options")
 147                                 || !strcmp(cmd, "install")
 148                                 || !strcmp(cmd, "remove")
 149                                 || !strcmp(cmd, "softdep")
 150                                 || !strcmp(cmd, "config")) {
 151                         INFO(ctx, "%s: command %s not implemented yet\n",
 152                                                                 filename, cmd);
 153                 } else {
 154 syntax_error:
 155                         ERR(ctx, "%s line %u: ignoring bad line starting with '%s'\n",
 156                                                 filename, linenum, cmd);
 157                 }
 158
 159 done_next:
 160                 free(line);
 161         }
 162
 163         fclose(fp);
 164
 165         return 0;
 166 }
 167
 168 void kmod_free_config(struct kmod_ctx *ctx, struct kmod_config *config)
 169 {
 170         while (config->aliases)
 171                 config->aliases =  free_alias(ctx, config->aliases);
 172
 173         while (config->blacklists)
 174                 config->blacklists = free_blacklist(ctx, config->blacklists);
 175 }
 176
 177 static bool conf_files_filter(struct kmod_ctx *ctx, const char *path,
 178                                                         const char *fn)
 179 {
 180         size_t len = strlen(fn);
 181
 182         if (fn[0] == '.')
 183                 return 1;
 184
 185         if (len < 6 || (strcmp(&fn[len - 5], ".conf") != 0
 186                                 && strcmp(&fn[len - 6], ".alias"))) {
 187                 INFO(ctx, "All config files need .conf: %s/%s, "
 188                                 "it will be ignored in a future release\n",
 189                                 path, fn);
 190                 return 1;
 191         }
 192
 193         return 0;
 194 }
 195
 196 static int conf_files_list(struct kmod_ctx *ctx, struct kmod_list **list,
 197                                                 const char *path, size_t *n)
 198 {
 199         struct stat st;
 200         DIR *d;
 201         int err;
 202
 203         if (stat(path, &st) < 0)
 204                 return -ENOENT;
 205
 206         if (!S_ISDIR(st.st_mode)) {
 207                 *list = kmod_list_append(*list, (void *)path);
 208                 *n += 1;
 209                 return 0;
 210         }
 211
 212         d = opendir(path);
 213         if (d == NULL) {
 214                 err = errno;
 215                 ERR(ctx, "%m\n");
 216                 return -errno;
 217         }
 218
 219         for (;;) {
 220                 struct dirent ent, *entp;
 221                 char *p;
 222
 223                 err = readdir_r(d, &ent, &entp);
 224                 if (err != 0) {
 225                         err = -err;
 226                         goto finish;
 227                 }
 228
 229                 if (entp == NULL)
 230                         break;
 231
 232                 if (conf_files_filter(ctx, path, entp->d_name) == 1)
 233                         continue;
 234
 235                 if (asprintf(&p, "%s/%s", path, entp->d_name) < 0) {
 236                         err = -ENOMEM;
 237                         goto finish;
 238                 }
 239
 240                 DBG(ctx, "%s\n", p);
 241
 242                 *list = kmod_list_append(*list, p);
 243                 *n += 1;
 244         }
 245
 246 finish:
 247         closedir(d);
 248         return err;
 249 }
 250
 251 static int base_cmp(const void *a, const void *b)
 252 {
 253         const char *s1, *s2;
 254
 255         s1 = *(char * const *)a;
 256         s2 = *(char * const *)b;
 257
 258         return strcmp(basename(s1), basename(s2));
 259 }
 260
 261 int kmod_parse_config(struct kmod_ctx *ctx, struct kmod_config *config)
 262 {
 263
 264         size_t i, n = 0;
 265         char **files = NULL;
 266         int err = 0;
 267         struct kmod_list *list = NULL, *l;
 268
 269         for (i = 0; i < ARRAY_SIZE(config_files); i++)
 270                 conf_files_list(ctx, &list, config_files[i], &n);
 271
 272         files = malloc(sizeof(char *) * n);
 273         if (files == NULL) {
 274                 err = -ENOMEM;
 275                 goto finish;
 276         }
 277
 278         i = 0;
 279         kmod_list_foreach(l, list) {
 280                 files[i] = l->data;
 281                 i++;
 282         }
 283
 284         qsort(files, n, sizeof(char *), base_cmp);
 285
 286         for (i = 0; i < n; i++)
 287                 kmod_parse_config_file(ctx, files[i], config);
 288
 289 finish:
 290         free(files);
 291
 292         while (list) {
 293                 free(list->data);
 294                 list = kmod_list_remove(list);
 295         }
 296
 297         return err;
 298 }