path: root/modutils/modinfo.c (plain)
blob: a0b2ce74dee7e1c32c8ea9e761a52e10f762da34

1	/* vi: set sw=4 ts=4: */
2	/*
3	* modinfo - retrieve module info
4	* Copyright (c) 2008 Pascal Bellard
5	*
6	* Licensed under GPLv2 or later, see file LICENSE in this source tree.
7	*/
8
9	//applet:IF_MODINFO(APPLET(modinfo, BB_DIR_SBIN, BB_SUID_DROP))
10
11	//kbuild:lib-$(CONFIG_MODINFO) += modinfo.o modutils.o
12
13	//config:config MODINFO
14	//config: bool "modinfo"
15	//config: default y
16	//config: select PLATFORM_LINUX
17	//config: help
18	//config: Show information about a Linux Kernel module
19
20	#include <fnmatch.h>
21	#include <sys/utsname.h> /* uname() */
22	#include "libbb.h"
23	#include "modutils.h"
24
25	#if defined(ANDROID) || defined(__ANDROID__)
26	#define DONT_USE_UTS_REL_FOLDER
27	#endif
28
29	enum {
30	OPT_TAGS = (1 << 12) - 1, /* shortcut count */
31	OPT_F = (1 << 12), /* field name */
32	OPT_0 = (1 << 13), /* \0 as separator */
33	};
34
35	struct modinfo_env {
36	char *field;
37	int tags;
38	};
39
40	static int display(const char *data, const char *pattern, int flag)
41	{
42	if (flag) {
43	int n = printf("%s:", pattern);
44	while (n++ < 16)
45	bb_putchar(' ');
46	}
47	return printf("%s%c", data, (option_mask32 & OPT_0) ? '\0' : '\n');
48	}
49
50	static void modinfo(const char *path, const char *version,
51	const struct modinfo_env *env)
52	{
53	static const char *const shortcuts[] = {
54	"filename",
55	"license",
56	"author",
57	"description",
58	"version",
59	"alias",
60	"srcversion",
61	"depends",
62	"uts_release",
63	"vermagic",
64	"parm",
65	"firmware",
66	};
67	size_t len;
68	int j, length;
69	char *ptr, *fullpath, *the_module;
70	const char *field = env->field;
71	int tags = env->tags;
72
73	if (tags & 1) { /* filename */
74	display(path, shortcuts[0], 1 != tags);
75	}
76
77	len = MAXINT(ssize_t);
78	the_module = xmalloc_open_zipped_read_close(path, &len);
79	if (!the_module) {
80	if (path[0] == '/')
81	return;
82	/* Newer depmod puts relative paths in modules.dep */
83	fullpath = xasprintf("%s/%s/%s", CONFIG_DEFAULT_MODULES_DIR, version, path);
84	the_module = xmalloc_open_zipped_read_close(fullpath, &len);
85	#ifdef DONT_USE_UTS_REL_FOLDER
86	if (!the_module) {
87	free((char*)fullpath);
88	fullpath = xasprintf("%s/%s", CONFIG_DEFAULT_MODULES_DIR, path);
89	the_module = xmalloc_open_zipped_read_close(fullpath, &len);
90	}
91	#endif
92	free((char*)fullpath);
93	if (!the_module) {
94	// outputs system error msg
95	bb_perror_msg("\n");
96	return;
97	}
98	}
99
100	if (field)
101	tags |= OPT_F;
102	for (j = 1; (1<<j) & (OPT_TAGS + OPT_F); j++) {
103	const char *pattern;
104
105	if (!((1<<j) & tags))
106	continue;
107	pattern = field;
108	if ((1<<j) & OPT_TAGS)
109	pattern = shortcuts[j];
110	length = strlen(pattern);
111	ptr = the_module;
112	while (1) {
113	ptr = memchr(ptr, *pattern, len - (ptr - (char*)the_module));
114	if (ptr == NULL) /* no occurance left, done */
115	break;
116	if (strncmp(ptr, pattern, length) == 0 && ptr[length] == '=') {
117	/* field prefixes are 0x80 or 0x00 */
118	if ((ptr[-1] & 0x7F) == '\0') {
119	ptr += length + 1;
120	ptr += display(ptr, pattern, (1<<j) != tags);
121	}
122	}
123	++ptr;
124	}
125	}
126	free(the_module);
127	}
128
129	//usage:#define modinfo_trivial_usage
130	//usage: "[-adlp0] [-F keyword] MODULE"
131	//usage:#define modinfo_full_usage "\n\n"
132	//usage: " -a Shortcut for '-F author'"
133	//usage: "\n -d Shortcut for '-F description'"
134	//usage: "\n -l Shortcut for '-F license'"
135	//usage: "\n -p Shortcut for '-F parm'"
136	//usage: "\n -F keyword Keyword to look for"
137	//usage: "\n -0 Separate output with NULs"
138	//usage:#define modinfo_example_usage
139	//usage: "$ modinfo -F vermagic loop\n"
140
141	int modinfo_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
142	int modinfo_main(int argc UNUSED_PARAM, char **argv)
143	{
144	struct modinfo_env env;
145	char name[MODULE_NAME_LEN];
146	struct utsname uts;
147	parser_t *parser;
148	char *colon, *tokens[2];
149	unsigned opts;
150	unsigned i;
151
152	env.field = NULL;
153	opt_complementary = "-1"; /* minimum one param */
154	opts = getopt32(argv, "nladvAsDumpF:0", &env.field);
155	env.tags = opts & OPT_TAGS ? opts & OPT_TAGS : OPT_TAGS;
156	argv += optind;
157
158	uname(&uts);
159	parser = config_open2(
160	xasprintf("%s/%s/%s", CONFIG_DEFAULT_MODULES_DIR, uts.release, CONFIG_DEFAULT_DEPMOD_FILE),
161	fopen_for_read
162	);
163
164	#ifdef DONT_USE_UTS_REL_FOLDER
165	if (!parser) {
166	parser = config_open2(
167	xasprintf("%s/%s", CONFIG_DEFAULT_MODULES_DIR, CONFIG_DEFAULT_DEPMOD_FILE),
168	fopen_for_read
169	);
170	}
171	#endif
172	if (!parser) {
173	strcpy(uts.release,"");
174	goto no_modules_dep;
175	}
176
177	while (config_read(parser, tokens, 2, 1, "# \t", PARSE_NORMAL)) {
178	colon = last_char_is(tokens[0], ':');
179	if (colon == NULL)
180	continue;
181	*colon = '\0';
182	filename2modname(tokens[0], name);
183	for (i = 0; argv[i]; i++) {
184	if (fnmatch(argv[i], name, 0) == 0) {
185	modinfo(tokens[0], uts.release, &env);
186	argv[i] = (char *) "";
187	}
188	}
189	}
190	if (ENABLE_FEATURE_CLEAN_UP)
191	config_close(parser);
192
193	no_modules_dep:
194	for (i = 0; argv[i]; i++) {
195	if (argv[i][0]) {
196	modinfo(argv[i], uts.release, &env);
197	}
198	}
199
200	return 0;
201	}
202