tools/objtool/objtool.c

   1 /*
   2  * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com>
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 /*
  19  * objtool:
  20  *
  21  * The 'check' subcmd analyzes every .o file and ensures the validity of its
  22  * stack trace metadata.  It enforces a set of rules on asm code and C inline
  23  * assembly code so that stack traces can be reliable.
  24  *
  25  * For more information, see tools/objtool/Documentation/stack-validation.txt.
  26  */
  27
  28 #include <stdio.h>
  29 #include <stdbool.h>
  30 #include <string.h>
  31 #include <stdlib.h>
  32 #include <subcmd/exec-cmd.h>
  33 #include <subcmd/pager.h>
  34 #include <linux/kernel.h>
  35
  36 #include "builtin.h"
  37
  38 struct cmd_struct {
  39         const char *name;
  40         int (*fn)(int, const char **);
  41         const char *help;
  42 };
  43
  44 static const char objtool_usage_string[] =
  45         "objtool COMMAND [ARGS]";
  46
  47 static struct cmd_struct objtool_cmds[] = {
  48         {"check",       cmd_check,      "Perform stack metadata validation on an object file" },
  49         {"orc",         cmd_orc,        "Generate in-place ORC unwind tables for an object file" },
  50 };
  51
  52 bool help;
  53
  54 static void cmd_usage(void)
  55 {
  56         unsigned int i, longest = 0;
  57
  58         printf("\n usage: %s\n\n", objtool_usage_string);
  59
  60         for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) {
  61                 if (longest < strlen(objtool_cmds[i].name))
  62                         longest = strlen(objtool_cmds[i].name);
  63         }
  64
  65         puts(" Commands:");
  66         for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) {
  67                 printf("   %-*s   ", longest, objtool_cmds[i].name);
  68                 puts(objtool_cmds[i].help);
  69         }
  70
  71         printf("\n");
  72
  73         exit(129);
  74 }
  75
  76 static void handle_options(int *argc, const char ***argv)
  77 {
  78         while (*argc > 0) {
  79                 const char *cmd = (*argv)[0];
  80
  81                 if (cmd[0] != '-')
  82                         break;
  83
  84                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "-h")) {
  85                         help = true;
  86                         break;
  87                 } else {
  88                         fprintf(stderr, "Unknown option: %s\n", cmd);
  89                         cmd_usage();
  90                 }
  91
  92                 (*argv)++;
  93                 (*argc)--;
  94         }
  95 }
  96
  97 static void handle_internal_command(int argc, const char **argv)
  98 {
  99         const char *cmd = argv[0];
 100         unsigned int i, ret;
 101
 102         for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) {
 103                 struct cmd_struct *p = objtool_cmds+i;
 104
 105                 if (strcmp(p->name, cmd))
 106                         continue;
 107
 108                 ret = p->fn(argc, argv);
 109
 110                 exit(ret);
 111         }
 112
 113         cmd_usage();
 114 }
 115
 116 int main(int argc, const char **argv)
 117 {
 118         static const char *UNUSED = "OBJTOOL_NOT_IMPLEMENTED";
 119
 120         /* libsubcmd init */
 121         exec_cmd_init("objtool", UNUSED, UNUSED, UNUSED);
 122         pager_init(UNUSED);
 123
 124         argv++;
 125         argc--;
 126         handle_options(&argc, &argv);
 127
 128         if (!argc || help)
 129                 cmd_usage();
 130
 131         handle_internal_command(argc, argv);
 132
 133         return 0;
 134 }