tools/objtool/objtool.c

   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         if (!help)
  62                 exit(129);
  63         exit(0);
  64 }
  65
  66 static void handle_options(int *argc, const char ***argv)
  67 {
  68         while (*argc > 0) {
  69                 const char *cmd = (*argv)[0];
  70
  71                 if (cmd[0] != '-')
  72                         break;
  73
  74                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "-h")) {
  75                         help = true;
  76                         break;
  77                 } else {
  78                         fprintf(stderr, "Unknown option: %s\n", cmd);
  79                         cmd_usage();
  80                 }
  81
  82                 (*argv)++;
  83                 (*argc)--;
  84         }
  85 }
  86
  87 static void handle_internal_command(int argc, const char **argv)
  88 {
  89         const char *cmd = argv[0];
  90         unsigned int i, ret;
  91
  92         for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) {
  93                 struct cmd_struct *p = objtool_cmds+i;
  94
  95                 if (strcmp(p->name, cmd))
  96                         continue;
  97
  98                 ret = p->fn(argc, argv);
  99
 100                 exit(ret);
 101         }
 102
 103         cmd_usage();
 104 }
 105
 106 int main(int argc, const char **argv)
 107 {
 108         static const char *UNUSED = "OBJTOOL_NOT_IMPLEMENTED";
 109
 110         /* libsubcmd init */
 111         exec_cmd_init("objtool", UNUSED, UNUSED, UNUSED);
 112         pager_init(UNUSED);
 113
 114         argv++;
 115         argc--;
 116         handle_options(&argc, &argv);
 117
 118         if (!argc || help)
 119                 cmd_usage();
 120
 121         handle_internal_command(argc, argv);
 122
 123         return 0;
 124 }