1 /* vi: set sw=4 ts=4: */
2 /*
3 * depmod - generate modules.dep
4 * Copyright (c) 2008 Bernhard Reutner-Fischer
5 * Copyrihgt (c) 2008 Timo Teras <timo.teras@iki.fi>
6 * Copyright (c) 2008 Vladimir Dronnikov
7 *
8 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
9 */
10 //config:config DEPMOD
11 //config: bool "depmod (27 kb)"
12 //config: default y
13 //config: help
14 //config: depmod generates modules.dep (and potentially modules.alias
15 //config: and modules.symbols) that contain dependency information
16 //config: for modprobe.
17
18 //applet:IF_DEPMOD(IF_NOT_MODPROBE_SMALL(APPLET(depmod, BB_DIR_SBIN, BB_SUID_DROP)))
19
20 //kbuild:ifneq ($(CONFIG_MODPROBE_SMALL),y)
21 //kbuild:lib-$(CONFIG_DEPMOD) += depmod.o modutils.o
22 //kbuild:endif
23
24 #include "libbb.h"
25 #include "modutils.h"
26 #include <sys/utsname.h> /* uname() */
27
28 /*
29 * Theory of operation:
30 * - iterate over all modules and record their full path
31 * - iterate over all modules looking for "depends=" entries
32 * for each depends, look through our list of full paths and emit if found
33 */
34
parse_module(struct recursive_state * state,const char * fname,struct stat * sb UNUSED_PARAM)35 static int FAST_FUNC parse_module(struct recursive_state *state,
36 const char *fname,
37 struct stat *sb UNUSED_PARAM)
38 {
39 module_db *modules = state->userData;
40 char *image, *ptr;
41 module_entry *e;
42
43 /* Arbitrary. Was sb->st_size, but that breaks .gz etc */
44 size_t len = (64*1024*1024 - 4096);
45
46 if (strrstr(fname, ".ko") == NULL)
47 return TRUE;
48
49 image = xmalloc_open_zipped_read_close(fname, &len);
50
51 e = moddb_get_or_create(modules, bb_get_last_path_component_nostrip(fname));
52 e->name = xstrdup(fname + 2); /* skip "./" */
53
54 for (ptr = image; ptr < image + len - 10; ptr++) {
55 if (is_prefixed_with(ptr, "depends=")) {
56 char *u;
57
58 ptr += 8;
59 for (u = ptr; *u; u++)
60 if (*u == '-')
61 *u = '_';
62 ptr += string_to_llist(ptr, &e->deps, ",");
63 } else if (ENABLE_FEATURE_MODUTILS_ALIAS
64 && is_prefixed_with(ptr, "alias=")
65 ) {
66 llist_add_to(&e->aliases, xstrdup(ptr + 6));
67 ptr += strlen(ptr);
68 } else if (ENABLE_FEATURE_MODUTILS_SYMBOLS
69 && is_prefixed_with(ptr, "__ksymtab_")
70 ) {
71 ptr += 10;
72 if (is_prefixed_with(ptr, "gpl")
73 || strcmp(ptr, "strings") == 0
74 ) {
75 continue;
76 }
77 llist_add_to(&e->symbols, xstrdup(ptr));
78 ptr += strlen(ptr);
79 }
80 }
81 free(image);
82
83 return TRUE;
84 }
85
order_dep_list(module_db * modules,module_entry * start,llist_t * add)86 static void order_dep_list(module_db *modules, module_entry *start, llist_t *add)
87 {
88 module_entry *m;
89 llist_t *n;
90
91 for (n = add; n != NULL; n = n->link) {
92 m = moddb_get(modules, n->data);
93 if (m == NULL)
94 continue;
95
96 /* unlink current entry */
97 m->dnext->dprev = m->dprev;
98 m->dprev->dnext = m->dnext;
99
100 /* and add it to tail */
101 m->dnext = start;
102 m->dprev = start->dprev;
103 start->dprev->dnext = m;
104 start->dprev = m;
105
106 /* recurse */
107 order_dep_list(modules, start, m->deps);
108 }
109 }
110
xfreopen_write(const char * file,FILE * f)111 static void xfreopen_write(const char *file, FILE *f)
112 {
113 if (freopen(file, "w", f) == NULL)
114 bb_perror_msg_and_die("can't open '%s'", file);
115 }
116
117 //usage:#if !ENABLE_MODPROBE_SMALL
118 //usage:#define depmod_trivial_usage "[-n] [-b BASE] [VERSION] [MODFILES]..."
119 //usage:#define depmod_full_usage "\n\n"
120 //usage: "Generate modules.dep, alias, and symbols files"
121 //usage: "\n"
122 //usage: "\n -b BASE Use BASE/lib/modules/VERSION"
123 //usage: "\n -n Dry run: print files to stdout"
124 //usage:#endif
125
126 /* Upstream usage:
127 * [-aAenv] [-C FILE or DIR] [-b BASE] [-F System.map] [VERSION] [MODFILES]...
128 * -a --all
129 * Probe all modules. Default if no MODFILES.
130 * -A --quick
131 * Check modules.dep's mtime against module files' mtimes.
132 * -b --basedir BASE
133 * Use $BASE/lib/modules/VERSION
134 * -C --config FILE or DIR
135 * Path to /etc/depmod.conf or /etc/depmod.d/
136 * -e --errsyms
137 * When combined with the -F option, this reports any symbols
138 * which are not supplied by other modules or kernel.
139 * -F --filesyms System.map
140 * -n --dry-run
141 * Print modules.dep etc to standard output
142 * -v --verbose
143 * Print to stdout all the symbols each module depends on
144 * and the module's file name which provides that symbol.
145 * -r No-op
146 * -u No-op
147 * -q No-op
148 *
149 * So far we only support: [-n] [-b BASE] [VERSION] [MODFILES]...
150 * Accepted but ignored:
151 * -aAe
152 * -F System.map
153 * -C FILE/DIR
154 *
155 * Not accepted: -v
156 */
157 enum {
158 //OPT_a = (1 << 0), /* All modules, ignore mods in argv */
159 //OPT_A = (1 << 1), /* Only emit .ko that are newer than modules.dep file */
160 OPT_b = (1 << 2), /* base directory when modules are in staging area */
161 //OPT_e = (1 << 3), /* with -F, print unresolved symbols */
162 //OPT_F = (1 << 4), /* System.map that contains the symbols */
163 OPT_n = (1 << 5), /* dry-run, print to stdout only */
164 OPT_r = (1 << 6), /* Compat dummy. Linux Makefile uses it */
165 OPT_u = (1 << 7), /* -u,--unresolved-error: ignored */
166 OPT_q = (1 << 8), /* -q,--quiet: ignored */
167 OPT_C = (1 << 9), /* -C,--config etc_modules_conf: ignored */
168 };
169
170 int depmod_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
depmod_main(int argc UNUSED_PARAM,char ** argv)171 int depmod_main(int argc UNUSED_PARAM, char **argv)
172 {
173 module_db modules;
174 module_entry *m, *dep;
175 const char *moddir_base = "/";
176 char *moddir, *version;
177 struct utsname uts;
178 unsigned i;
179 int tmp;
180
181 getopt32(argv, "aAb:eF:nruqC:", &moddir_base, NULL, NULL);
182 argv += optind;
183
184 /* goto modules location */
185 xchdir(moddir_base);
186
187 /* If a version is provided, then that kernel version's module directory
188 * is used, rather than the current kernel version (as returned by
189 * "uname -r"). */
190 if (*argv && sscanf(*argv, "%u.%u.%u", &tmp, &tmp, &tmp) == 3) {
191 version = *argv++;
192 } else {
193 uname(&uts);
194 version = uts.release;
195 }
196 moddir = concat_path_file(&CONFIG_DEFAULT_MODULES_DIR[1], version);
197 xchdir(moddir);
198 if (ENABLE_FEATURE_CLEAN_UP)
199 free(moddir);
200
201 /* Scan modules */
202 memset(&modules, 0, sizeof(modules));
203 if (*argv) {
204 do {
205 recursive_action(*argv, 0 /* no ACTION_RECURSE! */,
206 parse_module, NULL, &modules);
207 } while (*++argv);
208 } else {
209 recursive_action(".", ACTION_RECURSE,
210 parse_module, NULL, &modules);
211 }
212
213 /* Generate dependency and alias files */
214 if (!(option_mask32 & OPT_n))
215 xfreopen_write(CONFIG_DEFAULT_DEPMOD_FILE, stdout);
216
217 moddb_foreach_module(&modules, m, i) {
218 printf("%s:", m->name);
219
220 order_dep_list(&modules, m, m->deps);
221 while (m->dnext != m) {
222 dep = m->dnext;
223 printf(" %s", dep->name);
224
225 /* unlink current entry */
226 dep->dnext->dprev = dep->dprev;
227 dep->dprev->dnext = dep->dnext;
228 dep->dnext = dep->dprev = dep;
229 }
230 bb_putchar('\n');
231 }
232
233 #if ENABLE_FEATURE_MODUTILS_ALIAS
234 if (!(option_mask32 & OPT_n))
235 xfreopen_write("modules.alias", stdout);
236 moddb_foreach_module(&modules, m, i) {
237 while (m->aliases) {
238 /*
239 * Last word used to be a basename
240 * (filename with path and .ko.* stripped)
241 * at the time of module-init-tools 3.4.
242 * kmod v.12 uses module name, i.e., s/-/_/g.
243 */
244 printf("alias %s %s\n",
245 (char*)llist_pop(&m->aliases),
246 m->modname);
247 }
248 }
249 #endif
250 #if ENABLE_FEATURE_MODUTILS_SYMBOLS
251 if (!(option_mask32 & OPT_n))
252 xfreopen_write("modules.symbols", stdout);
253 moddb_foreach_module(&modules, m, i) {
254 while (m->symbols) {
255 printf("alias symbol:%s %s\n",
256 (char*)llist_pop(&m->symbols),
257 m->modname);
258 }
259 }
260 #endif
261
262 if (ENABLE_FEATURE_CLEAN_UP)
263 moddb_free(&modules);
264
265 return EXIT_SUCCESS;
266 }
267