ftpd: document NLST format
[oweals/busybox.git] / modutils / modprobe.c
index ad39be059c523a9293fdc60fd7ae46bdd6bff8f0..218a898a8ea7f3b0a899108e77277ac0b2e6b376 100644 (file)
 #include <sys/utsname.h>
 #include <fnmatch.h>
 
-struct modprobe_option {
-       char *module;
-       char *option;
+//#define DBG(...) bb_error_msg(__VA_ARGS__)
+#define DBG(...) ((void)0)
+
+#define MODULE_FLAG_LOADED             0x0001
+#define MODULE_FLAG_NEED_DEPS          0x0002
+/* "was seen in modules.dep": */
+#define MODULE_FLAG_FOUND_IN_MODDEP    0x0004
+#define MODULE_FLAG_BLACKLISTED                0x0008
+
+struct module_entry { /* I'll call it ME. */
+       unsigned flags;
+       char *modname; /* stripped of /path/, .ext and s/-/_/g */
+       const char *probed_name; /* verbatim as seen on cmdline */
+       char *options; /* options from config files */
+       llist_t *realnames; /* strings. if this module is an alias, */
+       /* real module name is one of these. */
+//Can there really be more than one? Example from real kernel?
+       llist_t *deps; /* strings. modules we depend on */
 };
 
-struct modprobe_conf {
-       char probename[MODULE_NAME_LEN];
-       llist_t *options;
-       llist_t *aliases;
-#if ENABLE_FEATURE_MODPROBE_BLACKLIST
-#define add_to_blacklist(conf, name) llist_add_to(&conf->blacklist, name)
-#define check_blacklist(conf, name) (llist_find(conf->blacklist, name) == NULL)
-       llist_t *blacklist;
-#else
-#define add_to_blacklist(conf, name) do {} while (0)
-#define check_blacklist(conf, name) (1)
-#endif
-};
-
-#define MODPROBE_OPTS  "acdlnrt:VC:" USE_FEATURE_MODPROBE_BLACKLIST("b")
+#define MODPROBE_OPTS  "acdlnrt:VC:" USE_FEATURE_MODPROBE_BLACKLIST("b")
 enum {
        MODPROBE_OPT_INSERT_ALL = (INSMOD_OPT_UNUSED << 0), /* a */
        MODPROBE_OPT_DUMP_ONLY  = (INSMOD_OPT_UNUSED << 1), /* c */
@@ -46,30 +47,92 @@ enum {
        MODPROBE_OPT_BLACKLIST  = (INSMOD_OPT_UNUSED << 9) * ENABLE_FEATURE_MODPROBE_BLACKLIST,
 };
 
-static llist_t *loaded;
+struct globals {
+       llist_t *db; /* MEs of all modules ever seen (caching for speed) */
+       llist_t *probes; /* MEs of module(s) requested on cmdline */
+       char *cmdline_mopts; /* module options from cmdline */
+       int num_unresolved_deps;
+       /* bool. "Did we have 'symbol:FOO' requested on cmdline?" */
+       smallint need_symbols;
+};
+#define G (*(struct globals*)&bb_common_bufsiz1)
+#define INIT_G() do { } while (0)
+
+
+static int read_config(const char *path);
+
+static char *gather_options_str(char *opts, const char *append)
+{
+       /* Speed-optimized. We call gather_options_str many times. */
+       if (opts == NULL) {
+               opts = xstrdup(append);
+       } else {
+               int optlen = strlen(opts);
+               opts = xrealloc(opts, optlen + strlen(append) + 2);
+               sprintf(opts + optlen, " %s", append);
+       }
+       return opts;
+}
+
+static struct module_entry *helper_get_module(const char *module, int create)
+{
+       char modname[MODULE_NAME_LEN];
+       struct module_entry *e;
+       llist_t *l;
+
+       filename2modname(module, modname);
+       for (l = G.db; l != NULL; l = l->link) {
+               e = (struct module_entry *) l->data;
+               if (strcmp(e->modname, modname) == 0)
+                       return e;
+       }
+       if (!create)
+               return NULL;
 
-static int read_config(struct modprobe_conf *conf, const char *path);
+       e = xzalloc(sizeof(*e));
+       e->modname = xstrdup(modname);
+       llist_add_to(&G.db, e);
+
+       return e;
+}
+static struct module_entry *get_or_add_modentry(const char *module)
+{
+       return helper_get_module(module, 1);
+}
+static struct module_entry *get_modentry(const char *module)
+{
+       return helper_get_module(module, 0);
+}
 
-static void add_option(llist_t **all_opts, const char *module, const char *opts)
+static void add_probe(const char *name)
 {
-       struct modprobe_option *o;
+       struct module_entry *m;
+
+       m = get_or_add_modentry(name);
+       if (m->flags & MODULE_FLAG_LOADED) {
+               DBG("skipping %s, it is already loaded", name);
+               return;
+       }
 
-       o = xzalloc(sizeof(struct modprobe_option));
-       if (module)
-               o->module = filename2modname(module, NULL);
-       o->option = xstrdup(opts);
-       llist_add_to(all_opts, o);
+       m->probed_name = name;
+       m->flags |= MODULE_FLAG_NEED_DEPS;
+       llist_add_to_end(&G.probes, m);
+       G.num_unresolved_deps++;
+       if (ENABLE_FEATURE_MODUTILS_SYMBOLS
+        && strncmp(m->modname, "symbol:", 7) == 0
+       ) {
+               G.need_symbols = 1;
+       }
 }
 
 static int FAST_FUNC config_file_action(const char *filename,
                                        struct stat *statbuf UNUSED_PARAM,
-                                       void *userdata,
+                                       void *userdata UNUSED_PARAM,
                                        int depth UNUSED_PARAM)
 {
-       struct modprobe_conf *conf = (struct modprobe_conf *) userdata;
-       RESERVE_CONFIG_BUFFER(modname, MODULE_NAME_LEN);
        char *tokens[3];
        parser_t *p;
+        struct module_entry *m;
        int rc = TRUE;
 
        if (bb_basename(filename)[0] == '.')
@@ -82,121 +145,156 @@ static int FAST_FUNC config_file_action(const char *filename,
        }
 
        while (config_read(p, tokens, 3, 2, "# \t", PARSE_NORMAL)) {
+//Use index_in_strings?
                if (strcmp(tokens[0], "alias") == 0) {
-                       filename2modname(tokens[1], modname);
-                       if (tokens[2] &&
-                           fnmatch(modname, conf->probename, 0) == 0)
-                               llist_add_to(&conf->aliases,
-                                       filename2modname(tokens[2], NULL));
+                       /* alias <wildcard> <modulename> */
+                       llist_t *l;
+                       char wildcard[MODULE_NAME_LEN];
+                       char *rmod;
+
+                       if (tokens[2] == NULL)
+                               continue;
+                       filename2modname(tokens[1], wildcard);
+
+                       for (l = G.probes; l != NULL; l = l->link) {
+                               m = (struct module_entry *) l->data;
+                               if (fnmatch(wildcard, m->modname, 0) != 0)
+                                       continue;
+                               rmod = filename2modname(tokens[2], NULL);
+                               llist_add_to(&m->realnames, rmod);
+
+                               if (m->flags & MODULE_FLAG_NEED_DEPS) {
+                                       m->flags &= ~MODULE_FLAG_NEED_DEPS;
+                                       G.num_unresolved_deps--;
+                               }
+
+                               m = get_or_add_modentry(rmod);
+                               if (!(m->flags & MODULE_FLAG_NEED_DEPS)) {
+                                       m->flags |= MODULE_FLAG_NEED_DEPS;
+                                       G.num_unresolved_deps++;
+                               }
+                       }
                } else if (strcmp(tokens[0], "options") == 0) {
-                       if (tokens[2])
-                               add_option(&conf->options, tokens[1], tokens[2]);
+                       /* options <modulename> <option...> */
+                       if (tokens[2] == NULL)
+                               continue;
+                       m = get_or_add_modentry(tokens[1]);
+                       m->options = gather_options_str(m->options, tokens[2]);
                } else if (strcmp(tokens[0], "include") == 0) {
-                       read_config(conf, tokens[1]);
-               } else if (ENABLE_FEATURE_MODPROBE_BLACKLIST &&
-                          strcmp(tokens[0], "blacklist") == 0) {
-                       add_to_blacklist(conf, xstrdup(tokens[1]));
+                       /* include <filename> */
+                       read_config(tokens[1]);
+               } else if (ENABLE_FEATURE_MODPROBE_BLACKLIST
+                && strcmp(tokens[0], "blacklist") == 0
+               ) {
+                       /* blacklist <modulename> */
+                       get_or_add_modentry(tokens[1])->flags |= MODULE_FLAG_BLACKLISTED;
                }
        }
        config_close(p);
 error:
-       if (ENABLE_FEATURE_CLEAN_UP)
-               RELEASE_CONFIG_BUFFER(modname);
        return rc;
 }
 
-static int read_config(struct modprobe_conf *conf, const char *path)
+static int read_config(const char *path)
 {
        return recursive_action(path, ACTION_RECURSE | ACTION_QUIET,
-                               config_file_action, NULL, conf, 1);
+                               config_file_action, NULL, NULL, 1);
 }
 
-static char *gather_options(llist_t *first, const char *module, int usecmdline)
+static int do_modprobe(struct module_entry *m)
 {
-       struct modprobe_option *opt;
-       llist_t *n;
-       char *opts = xstrdup("");
-       int optlen = 0;
+       struct module_entry *m2;
+       char *fn, *options;
+       int rc = -1;
 
-       for (n = first; n != NULL; n = n->link) {
-               opt = (struct modprobe_option *) n->data;
+       if (!(m->flags & MODULE_FLAG_FOUND_IN_MODDEP)) {
+               DBG("skipping %s, not found in modules.dep", m->modname);
+               return -ENOENT;
+       }
+       DBG("do_modprob'ing %s", m->modname);
 
-               if (opt->module == NULL && !usecmdline)
-                       continue;
-               if (opt->module != NULL && strcmp(opt->module, module) != 0)
-                       continue;
+       if (!(option_mask32 & MODPROBE_OPT_REMOVE))
+               m->deps = llist_rev(m->deps);
+
+       rc = 0;
+       while (m->deps && rc == 0) {
+               fn = llist_pop(&m->deps);
+               m2 = get_or_add_modentry(fn);
+               if (option_mask32 & MODPROBE_OPT_REMOVE) {
+                       if (bb_delete_module(m->modname, O_EXCL) != 0)
+                               rc = errno;
+               } else if (!(m2->flags & MODULE_FLAG_LOADED)) {
+                       options = m2->options;
+                       m2->options = NULL;
+                       if (m == m2)
+                               options = gather_options_str(options, G.cmdline_mopts);
+                       rc = bb_init_module(fn, options);
+                       DBG("loaded %s '%s', rc:%d", fn, options, rc);
+                       if (rc == 0)
+                               m2->flags |= MODULE_FLAG_LOADED;
+                       free(options);
+               } else {
+                       DBG("%s is already loaded, skipping", fn);
+               }
 
-               opts = xrealloc(opts, optlen + strlen(opt->option) + 2);
-               optlen += sprintf(opts + optlen, "%s ", opt->option);
+               free(fn);
        }
-       return opts;
+
+//FIXME: what if rc < 0?
+       if (rc > 0 && !(option_mask32 & INSMOD_OPT_SILENT)) {
+               bb_error_msg("failed to %sload module %s: %s",
+                       (option_mask32 & MODPROBE_OPT_REMOVE) ? "un" : "",
+                       m->probed_name ? m->probed_name : m->modname,
+                       moderror(rc)
+               );
+       }
+
+       return rc;
 }
 
-static int do_modprobe(struct modprobe_conf *conf, const char *module)
+static void load_modules_dep(void)
 {
-       RESERVE_CONFIG_BUFFER(modname, MODULE_NAME_LEN);
-       llist_t *deps = NULL;
-       char *fn, *options, *colon = NULL, *tokens[2];
+       struct module_entry *m;
+       char *colon, *tokens[2];
        parser_t *p;
-       int rc = -1;
-
-       p = config_open2(CONFIG_DEFAULT_DEPMOD_FILE, fopen_for_read);
-       if (p == NULL)
-               goto error;
 
-       while (config_read(p, tokens, 2, 1, "# \t", PARSE_NORMAL)) {
+       /* Modprobe does not work at all without modprobe.dep,
+        * even if the full module name is given. Returning error here
+        * was making us later confuse user with this message:
+        * "module /full/path/to/existing/file/module.ko not found".
+        * It's better to die immediately, with good message.
+        * xfopen_for_read provides that. */
+       p = config_open2(CONFIG_DEFAULT_DEPMOD_FILE, xfopen_for_read);
+
+       while (G.num_unresolved_deps
+        && config_read(p, tokens, 2, 1, "# \t", PARSE_NORMAL)
+       ) {
                colon = last_char_is(tokens[0], ':');
                if (colon == NULL)
                        continue;
+               *colon = 0;
 
-               filename2modname(tokens[0], modname);
-               if (strcmp(modname, module) == 0)
-                       break;
-
-               colon = NULL;
-       }
-       if (colon == NULL)
-               goto error_not_found;
-
-       colon[0] = '\0';
-       llist_add_to(&deps, xstrdup(tokens[0]));
-       if (tokens[1])
-               string_to_llist(tokens[1], &deps, " ");
-
-       if (!(option_mask32 & MODPROBE_OPT_REMOVE))
-               deps = llist_rev(deps);
+               m = get_modentry(tokens[0]);
+               if (m == NULL)
+                       continue;
 
-       rc = 0;
-       while (deps && rc == 0) {
-               fn = llist_pop(&deps);
-               filename2modname(fn, modname);
-               if (option_mask32 & MODPROBE_OPT_REMOVE) {
-                       if (bb_delete_module(modname, O_EXCL) != 0)
-                               rc = errno;
-               } else if (llist_find(loaded, modname) == NULL) {
-                       options = gather_options(conf->options, modname,
-                                                strcmp(modname, module) == 0);
-                       rc = bb_init_module(fn, options);
-                       if (rc == 0)
-                               llist_add_to(&loaded, xstrdup(modname));
-                       if (ENABLE_FEATURE_CLEAN_UP)
-                               free(options);
+               /* Optimization... */
+               if ((m->flags & MODULE_FLAG_LOADED)
+                && !(option_mask32 & MODPROBE_OPT_REMOVE)
+               ) {
+                       DBG("skip deps of %s, it's already loaded", tokens[0]);
+                       continue;
                }
 
-               if (ENABLE_FEATURE_CLEAN_UP)
-                       free(fn);
+               m->flags |= MODULE_FLAG_FOUND_IN_MODDEP;
+               if ((m->flags & MODULE_FLAG_NEED_DEPS) && (m->deps == NULL)) {
+                       G.num_unresolved_deps--;
+                       llist_add_to(&m->deps, xstrdup(tokens[0]));
+                       if (tokens[1])
+                               string_to_llist(tokens[1], &m->deps, " ");
+               }
        }
-
-error_not_found:
        config_close(p);
-error:
-       if (ENABLE_FEATURE_CLEAN_UP)
-               RELEASE_CONFIG_BUFFER(modname);
-       if (rc > 0 && !(option_mask32 & INSMOD_OPT_SILENT))
-               bb_error_msg("failed to %sload module %s: %s",
-                            (option_mask32 & MODPROBE_OPT_REMOVE) ? "un" : "",
-                            module, moderror(rc));
-       return rc;
 }
 
 int modprobe_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
@@ -205,84 +303,95 @@ int modprobe_main(int argc UNUSED_PARAM, char **argv)
        struct utsname uts;
        int rc;
        unsigned opt;
-       llist_t *options = NULL;
+       struct module_entry *me;
 
        opt_complementary = "q-v:v-q";
-       opt = getopt32(argv, INSMOD_OPTS MODPROBE_OPTS INSMOD_ARGS,
-                NULL, NULL);
+       opt = getopt32(argv, INSMOD_OPTS MODPROBE_OPTS INSMOD_ARGS, NULL, NULL);
        argv += optind;
 
        if (opt & (MODPROBE_OPT_DUMP_ONLY | MODPROBE_OPT_LIST_ONLY |
                                MODPROBE_OPT_SHOW_ONLY))
                bb_error_msg_and_die("not supported");
 
-       /* goto modules location */
-       xchdir(CONFIG_DEFAULT_MODULES_DIR);
-       uname(&uts);
-       xchdir(uts.release);
-
        if (!argv[0]) {
                if (opt & MODPROBE_OPT_REMOVE) {
+                       /* "modprobe -r" (w/o params).
+                        * "If name is NULL, all unused modules marked
+                        * autoclean will be removed".
+                        */
                        if (bb_delete_module(NULL, O_NONBLOCK|O_EXCL) != 0)
                                bb_perror_msg_and_die("rmmod");
                }
                return EXIT_SUCCESS;
        }
-       if (!(opt & MODPROBE_OPT_INSERT_ALL)) {
-               /* If not -a, we have only one module name,
-                * the rest of parameters are options */
-               add_option(&options, NULL, parse_cmdline_module_options(argv));
-               argv[1] = NULL;
-       }
 
-       /* cache modules */
+       /* Goto modules location */
+       xchdir(CONFIG_DEFAULT_MODULES_DIR);
+       uname(&uts);
+       xchdir(uts.release);
+
+       /* Retrieve module names of already loaded modules */
        {
                char *s;
                parser_t *parser = config_open2("/proc/modules", fopen_for_read);
                while (config_read(parser, &s, 1, 1, "# \t", PARSE_NORMAL & ~PARSE_GREEDY))
-                       llist_add_to(&loaded, xstrdup(s));
+                       get_or_add_modentry(s)->flags |= MODULE_FLAG_LOADED;
                config_close(parser);
        }
 
-       while (*argv) {
-               const char *arg = *argv;
-               struct modprobe_conf *conf;
-
-               conf = xzalloc(sizeof(*conf));
-               conf->options = options;
-               filename2modname(arg, conf->probename);
-               read_config(conf, "/etc/modprobe.conf");
-               read_config(conf, "/etc/modprobe.d");
-               if (ENABLE_FEATURE_MODUTILS_SYMBOLS
-                && conf->aliases == NULL
-                && strncmp(arg, "symbol:", 7) == 0
-               ) {
-                       read_config(conf, "modules.symbols");
-               }
+       if (opt & MODPROBE_OPT_INSERT_ALL) {
+               /* Each argument is a module name */
+               do {
+                       add_probe(*argv++);
+               } while (*argv);
+       } else {
+               /* First argument is module name, rest are parameters */
+               add_probe(argv[0]);
+               G.cmdline_mopts = parse_cmdline_module_options(argv);
+       }
 
-               if (ENABLE_FEATURE_MODUTILS_ALIAS && conf->aliases == NULL)
-                       read_config(conf, "modules.alias");
+       /* Happens if all requested modules are already loaded */
+       if (G.probes == NULL)
+               return EXIT_SUCCESS;
 
-               if (conf->aliases == NULL) {
-                       /* Try if module by literal name is found; literal
-                        * names are blacklist only if '-b' is given. */
-                       if (!(opt & MODPROBE_OPT_BLACKLIST) ||
-                           check_blacklist(conf, conf->probename)) {
-                               rc = do_modprobe(conf, conf->probename);
+       read_config("/etc/modprobe.conf");
+       read_config("/etc/modprobe.d");
+       if (ENABLE_FEATURE_MODUTILS_SYMBOLS && G.need_symbols)
+               read_config("modules.symbols");
+       load_modules_dep();
+       if (ENABLE_FEATURE_MODUTILS_ALIAS && G.num_unresolved_deps) {
+               read_config("modules.alias");
+               load_modules_dep();
+       }
+
+       while ((me = llist_pop(&G.probes)) != NULL) {
+               if (me->realnames == NULL) {
+                       /* This is not an alias. Literal names are blacklisted
+                        * only if '-b' is given.
+                        */
+                       if (!(opt & MODPROBE_OPT_BLACKLIST)
+                        || !(me->flags & MODULE_FLAG_BLACKLISTED)
+                       ) {
+                               rc = do_modprobe(me);
+//FIXME: what if rc > 0?
                                if (rc < 0 && !(opt & INSMOD_OPT_SILENT))
-                                       bb_error_msg("module %s not found", arg);
+                                       bb_error_msg("module %s not found",
+                                                    me->probed_name);
                        }
                } else {
-                       /* Probe all aliases */
-                       while (conf->aliases != NULL) {
-                               char *realname = llist_pop(&conf->aliases);
-                               if (check_blacklist(conf, realname))
-                                       do_modprobe(conf, realname);
-                               if (ENABLE_FEATURE_CLEAN_UP)
-                                       free(realname);
-                       }
+                       /* Probe all realnames */
+                       do {
+                               char *realname = llist_pop(&me->realnames);
+                               struct module_entry *m2;
+
+                               DBG("probing %s by realname %s", me->modname, realname);
+                               m2 = get_or_add_modentry(realname);
+                               if (!(m2->flags & MODULE_FLAG_BLACKLISTED))
+                                       do_modprobe(m2);
+//FIXME: error check?
+                               free(realname);
+                       } while (me->realnames != NULL);
                }
-               argv++;
        }
 
        return EXIT_SUCCESS;