xref: /openbmc/linux/tools/objtool/objtool.c (revision 8dde5715)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com>
4  */
5 
6 /*
7  * objtool:
8  *
9  * The 'check' subcmd analyzes every .o file and ensures the validity of its
10  * stack trace metadata.  It enforces a set of rules on asm code and C inline
11  * assembly code so that stack traces can be reliable.
12  *
13  * For more information, see tools/objtool/Documentation/stack-validation.txt.
14  */
15 
16 #include <stdio.h>
17 #include <stdbool.h>
18 #include <string.h>
19 #include <stdlib.h>
20 #include <subcmd/exec-cmd.h>
21 #include <subcmd/pager.h>
22 #include <linux/kernel.h>
23 
24 #include "builtin.h"
25 
26 struct cmd_struct {
27 	const char *name;
28 	int (*fn)(int, const char **);
29 	const char *help;
30 };
31 
32 static const char objtool_usage_string[] =
33 	"objtool COMMAND [ARGS]";
34 
35 static struct cmd_struct objtool_cmds[] = {
36 	{"check",	cmd_check,	"Perform stack metadata validation on an object file" },
37 	{"orc",		cmd_orc,	"Generate in-place ORC unwind tables for an object file" },
38 };
39 
40 bool help;
41 
42 static void cmd_usage(void)
43 {
44 	unsigned int i, longest = 0;
45 
46 	printf("\n usage: %s\n\n", objtool_usage_string);
47 
48 	for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) {
49 		if (longest < strlen(objtool_cmds[i].name))
50 			longest = strlen(objtool_cmds[i].name);
51 	}
52 
53 	puts(" Commands:");
54 	for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) {
55 		printf("   %-*s   ", longest, objtool_cmds[i].name);
56 		puts(objtool_cmds[i].help);
57 	}
58 
59 	printf("\n");
60 
61 	exit(129);
62 }
63 
64 static void handle_options(int *argc, const char ***argv)
65 {
66 	while (*argc > 0) {
67 		const char *cmd = (*argv)[0];
68 
69 		if (cmd[0] != '-')
70 			break;
71 
72 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "-h")) {
73 			help = true;
74 			break;
75 		} else {
76 			fprintf(stderr, "Unknown option: %s\n", cmd);
77 			cmd_usage();
78 		}
79 
80 		(*argv)++;
81 		(*argc)--;
82 	}
83 }
84 
85 static void handle_internal_command(int argc, const char **argv)
86 {
87 	const char *cmd = argv[0];
88 	unsigned int i, ret;
89 
90 	for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) {
91 		struct cmd_struct *p = objtool_cmds+i;
92 
93 		if (strcmp(p->name, cmd))
94 			continue;
95 
96 		ret = p->fn(argc, argv);
97 
98 		exit(ret);
99 	}
100 
101 	cmd_usage();
102 }
103 
104 int main(int argc, const char **argv)
105 {
106 	static const char *UNUSED = "OBJTOOL_NOT_IMPLEMENTED";
107 
108 	/* libsubcmd init */
109 	exec_cmd_init("objtool", UNUSED, UNUSED, UNUSED);
110 	pager_init(UNUSED);
111 
112 	argv++;
113 	argc--;
114 	handle_options(&argc, &argv);
115 
116 	if (!argc || help)
117 		cmd_usage();
118 
119 	handle_internal_command(argc, argv);
120 
121 	return 0;
122 }
123