- add alias support

2 files changed, 115 insertions, 85 deletions

diff --git a/modutils/Config.in b/modutils/Config.in
index fb7fb2266..bf93c74a1 100644
--- a/modutils/Config.in
+++ b/modutils/Config.in
@@ -25,6 +25,16 @@ config FEATURE_DEPMOD_PRUNE_FANCY
 
           If unsure, say N.
 
+config FEATURE_DEPMOD_ALIAS
+        bool "alias support"
+        default n
+        depends on DEPMOD
+        help
+          By default modules.dep does not contain alias information.
+          Enable this to emit aliases of the form:
+
+            alias pcmcia:m*c*f03fn*pfn*pa*pb*pc*pd* parport_cs
+
 config INSMOD
         bool "insmod"
         default n
diff --git a/modutils/depmod.c b/modutils/depmod.c
index b0b09c235..09d31f4c0 100644
--- a/modutils/depmod.c
+++ b/modutils/depmod.c
@@ -10,12 +10,6 @@
 #define _GNU_SOURCE
 #include <libbb.h>
 #include <sys/utsname.h> /* uname() */
-#if ENABLE_DEBUG
-#include <assert.h>
-#define dbg_assert assert
-#else
-#define dbg_assert(stuff) do {} while (0)
-#endif
 /*
  * Theory of operation:
  * - iterate over all modules and record their full path
@@ -26,33 +20,33 @@
 typedef struct dep_lst_t {
         char *name;
         llist_t *dependencies;
+        llist_t *aliases;
         struct dep_lst_t *next;
 } dep_lst_t;
 
 struct globals {
         dep_lst_t *lst; /* modules without their corresponding extension */
-        size_t moddir_base_len; /* length of the "-b basedir" */
 };
 #define G (*(struct globals*)&bb_common_bufsiz1)
 /* We have to zero it out because of NOEXEC */
 #define INIT_G() memset(&G, 0, sizeof(G))
 
-static int fill_lst(const char *modulename, struct stat ATTRIBUTE_UNUSED *sb,
-                                        void ATTRIBUTE_UNUSED *data, int ATTRIBUTE_UNUSED depth)
+static char* find_keyword(void *the_module, size_t len, const char * const word)
 {
-
-        /* We get a file here. If the file does not have ".ko" but an
-         * intermittent dentry has, it's just their fault.
-         */
-        if (strrstr(modulename, ".ko") != NULL) {
-                dep_lst_t *new = xzalloc(sizeof(dep_lst_t));
-                new->name = xstrdup(modulename + G.moddir_base_len);
-                new->next = G.lst;
-                G.lst = new;
-        }
-        return TRUE;
+        char *ptr = the_module;
+        do {
+                /* search for the first char in word */
+                ptr = memchr(ptr, *word, len - (ptr - (char*)the_module));
+                if (ptr == NULL) /* no occurance left, done */
+                        return NULL;
+                if (!strncmp(ptr, word, strlen(word))) {
+                        ptr += strlen(word);
+                        break;
+                }
+                ++ptr;
+        } while (1);
+        return ptr;
 }
-
 static int fileAction(const char *fname, struct stat *sb,
                                         void ATTRIBUTE_UNUSED *data, int ATTRIBUTE_UNUSED depth)
 {
@@ -79,45 +73,37 @@ static int fileAction(const char *fname, struct stat *sb,
         close(fd);
         if (the_module == MAP_FAILED)
                 bb_perror_msg_and_die("mmap");
-        ptr = the_module;
-        this = G.lst;
-        do {
-                if (!strcmp(fname + G.moddir_base_len, this->name))
-                        break;
-                this = this->next;
-        } while (this);
-        dbg_assert (this);
-//bb_info_msg("fname='%s'", fname + G.moddir_base_len);
-        do {
-                /* search for a 'd' */
-                ptr = memchr(ptr, 'd', len - (ptr - (char*)the_module));
-                if (ptr == NULL) /* no d left, done */
-                        goto none;
-                if (!strncmp(ptr, "depends=", sizeof("depends=")-1))
-                        break;
-                ++ptr;
-        } while (1);
-        deps = depends = xstrdup (ptr + sizeof("depends=")-1);
+
+        this = xzalloc(sizeof(dep_lst_t));
+        this->name = xstrdup(fname);
+        this->next = G.lst;
+        G.lst = this;
+//bb_info_msg("fname='%s'", fname);
+        ptr = find_keyword(the_module, len, "depends=");
+        if (!*ptr)
+                goto d_none;
+        deps = depends = xstrdup(ptr);
 //bb_info_msg(" depends='%s'", depends);
         while (deps) {
-                dep_lst_t *all = G.lst;
-
                 ptr = strsep(&deps, ",");
-                while (all) {
-                        /* Compare the recorded filenames ignoring ".ko*" at the end.  */
-                        char *tmp = bb_get_last_path_component_nostrip(all->name);
-                        if (!strncmp(ptr, tmp, MAX(strlen(ptr),strrstr(tmp, ".ko") - tmp)))
-                                break; /* found it */
-                        all = all->next;
-                }
-                if (all) {
-                        dbg_assert(all->name); /* this cannot be empty */
-//bb_info_msg("[%s] -> '%s'", (char*)ptr, all->name);
-                        llist_add_to_end(&this->dependencies, all->name);
-                }
+//bb_info_msg("[%s] -> '%s'", fname, (char*)ptr);
+                llist_add_to_end(&this->dependencies, xstrdup(ptr));
         }
         free(depends);
- none:
+ d_none:
+        if (ENABLE_FEATURE_DEPMOD_ALIAS)
+        {
+                size_t pos = 0;
+                do {
+                        ptr = find_keyword(the_module + pos, len - pos, "alias=");
+                        if (ptr) {
+//bb_info_msg("[%s] alias '%s'", fname, (char*)ptr);
+                                        llist_add_to_end(&this->aliases, xstrdup(ptr));
+                        } else
+                                break;
+                        pos = (ptr - (char*)the_module);
+                } while (1);
+        }
         munmap(the_module, sb->st_size);
  skip:
         return TRUE;
@@ -127,6 +113,7 @@ int depmod_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int depmod_main(int ATTRIBUTE_UNUSED argc, char **argv)
 {
         int ret;
+        size_t moddir_base_len = 0; /* length of the "-b basedir" */
         char *moddir_base = NULL, *moddir, *system_map, *chp;
         FILE *filedes = stdout;
         enum {
@@ -157,13 +144,8 @@ int depmod_main(int ATTRIBUTE_UNUSED argc, char **argv)
         option_mask32 |= *argv == NULL;
 
         if (option_mask32 & ARG_b) {
-                G.moddir_base_len = strlen(moddir_base);
-                if (ENABLE_FEATURE_CLEAN_UP) {
-                        chp = moddir;
-                        moddir = concat_path_file(moddir_base, moddir);
-                        free (chp);
-                } else
-                        moddir = concat_path_file(moddir_base, moddir);
+                moddir_base_len = strlen(moddir_base) + 1;
+                xchdir(moddir_base);
         }
 
         if (!(option_mask32 & ARG_n)) { /* --dry-run */
@@ -173,23 +155,8 @@ int depmod_main(int ATTRIBUTE_UNUSED argc, char **argv)
                         free(chp);
         }
         ret = EXIT_SUCCESS;
-        /* We have to do a full walk to collect all needed data.  */
-        if (!recursive_action(moddir,
-                        ACTION_RECURSE, /* flags */
-                        fill_lst, /* file action */
-                        NULL, /* dir action */
-                        NULL, /* user data */
-                        0)) { /* depth */
-                if (ENABLE_FEATURE_CLEAN_UP)
-                        ret = EXIT_FAILURE;
-                else
-                        return EXIT_FAILURE;
-        }
-#if ENABLE_FEATURE_CLEAN_UP
-        else
-#endif
         do {
-                chp = option_mask32 & ARG_a ? moddir : *argv++;
+                chp = option_mask32 & ARG_a ? moddir : (*argv + moddir_base_len);
 
                 if (!recursive_action(chp,
                                 ACTION_RECURSE, /* flags */
@@ -199,8 +166,42 @@ int depmod_main(int ATTRIBUTE_UNUSED argc, char **argv)
                                 0)) { /* depth */
                         ret = EXIT_FAILURE;
                 }
-        } while (!(option_mask32 & ARG_a) && *argv);
+        } while (!(option_mask32 & ARG_a) && *++argv);
+
+        {
+        dep_lst_t *mods = G.lst;
+
+        /* Fixup the module names in the depends list */
+        while (mods) {
+                llist_t *deps = NULL, *old_deps = mods->dependencies;
+                
+                while (old_deps) {
+                        dep_lst_t *all = G.lst;
+                        char *longname = NULL;
+                        char *shortname = llist_pop(&old_deps);
 
+                        while (all) {
+                                char *nam = 
+                                        xstrdup(bb_get_last_path_component_nostrip(all->name));
+                                char *tmp = strrstr(nam, ".ko");
+
+                                *tmp = '\0';
+                                if (!strcmp(nam, shortname)) {
+                                        if (ENABLE_FEATURE_CLEAN_UP)
+                                                free(nam);
+                                        longname = all->name;
+                                        break;
+                                }
+                                free(nam);
+                                all = all->next;
+                        }
+                        llist_add_to_end(&deps, longname);
+                }
+                mods->dependencies = deps;
+                mods = mods->next;
+        }
+
+#if ENABLE_FEATURE_DEPMOD_PRUNE_FANCY
         /* modprobe allegedly wants dependencies without duplicates, i.e.
          * mod1: mod2 mod3
          * mod2: mod3
@@ -211,9 +212,7 @@ int depmod_main(int ATTRIBUTE_UNUSED argc, char **argv)
          * mod2: mod3
          * mod3:
          */
-        {
-        dep_lst_t *mods = G.lst;
-#if ENABLE_FEATURE_DEPMOD_PRUNE_FANCY
+        mods = G.lst;
         while (mods) {
                 llist_t *deps = mods->dependencies;
                 while (deps) {
@@ -241,15 +240,36 @@ int depmod_main(int ATTRIBUTE_UNUSED argc, char **argv)
                 }
                 mods = mods->next;
         }
+#endif
 
         mods = G.lst;
-#endif
         /* Finally print them.  */
         while (mods) {
                 fprintf(filedes, "%s:", mods->name);
-                while (mods->dependencies)
-                        fprintf(filedes, " %s", (char*)llist_pop(&mods->dependencies));
+                /* If we did not resolve all modules, then it's likely that we just did
+                 * not see the names of all prerequisites (which will be NULL in this
+                 * case).  */
+                while (mods->dependencies) {
+                        char *the_dep = llist_pop(&mods->dependencies);
+                        if (the_dep)
+                                fprintf(filedes, " %s", the_dep);
+                }
                 fprintf(filedes, "\n");
+                if (ENABLE_FEATURE_DEPMOD_ALIAS)
+                {
+                        char *shortname =
+                                xstrdup(bb_get_last_path_component_nostrip(mods->name));
+                        char *tmp = strrstr(shortname, ".ko");
+
+                        *tmp = '\0';
+                
+                        while (mods->aliases) {
+                                fprintf(filedes, "alias %s %s\n",
+                                        (char*)llist_pop(&mods->aliases),
+                                        shortname);
+                        }
+                        free(shortname);
+                }
                 mods = mods->next;
         }
         }