usr.bin/systat/symbols.c

   1 /*
   2  * Copyright (c) 2010 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #include <sys/types.h>
  36 #include <sys/sysctl.h>
  37
  38 #include <ctype.h>
  39 #include <devinfo.h>
  40 #include <err.h>
  41 #include <fcntl.h>
  42 #include <kvm.h>
  43 #include <limits.h>
  44 #include <nlist.h>
  45 #include <stdint.h>
  46 #include <stdio.h>
  47 #include <stdlib.h>
  48 #include <string.h>
  49 #include <unistd.h>
  50 #include <evtr.h>
  51 #include <stdarg.h>
  52 #include "symbols.h"
  53
  54 struct symdata {
  55         TAILQ_ENTRY(symdata) link;
  56         const char *symname;
  57         char *symaddr;
  58         char symtype;
  59 };
  60
  61 static TAILQ_HEAD(symlist, symdata) symlist;
  62 static struct symdata *symcache;
  63 static char *symbegin = (void *)(intptr_t)0;
  64 static char *symend = (void *)(intptr_t)-1;
  65
  66 void
  67 read_symbols(const char *file)
  68 {
  69         char buf[256];
  70         char cmd[256];
  71         size_t buflen = sizeof(buf);
  72         FILE *fp;
  73         struct symdata *sym;
  74         char *s1;
  75         char *s2;
  76         char *s3;
  77
  78         TAILQ_INIT(&symlist);
  79
  80         if (file == NULL) {
  81                 if (sysctlbyname("kern.bootfile", buf, &buflen, NULL, 0) < 0)
  82                         file = "/boot/kernel";
  83                 else
  84                         file = buf;
  85         }
  86         snprintf(cmd, sizeof(cmd), "nm -n %s", file);
  87         if ((fp = popen(cmd, "r")) != NULL) {
  88                 while (fgets(buf, sizeof(buf), fp) != NULL) {
  89                     s1 = strtok(buf, " \t\n");
  90                     s2 = strtok(NULL, " \t\n");
  91                     s3 = strtok(NULL, " \t\n");
  92                     if (s1 && s2 && s3) {
  93                         sym = malloc(sizeof(struct symdata));
  94                         sym->symaddr = (char *)strtoul(s1, NULL, 16);
  95                         sym->symtype = s2[0];
  96                         sym->symname = strdup(s3);
  97                         if (strcmp(s3, "kernbase") == 0)
  98                                 symbegin = sym->symaddr;
  99                         if (strcmp(s3, "end") == 0)
 100                                 symend = sym->symaddr;
 101                         TAILQ_INSERT_TAIL(&symlist, sym, link);
 102                     }
 103                 }
 104                 pclose(fp);
 105         }
 106         symcache = TAILQ_FIRST(&symlist);
 107 }
 108
 109 const char *
 110 address_to_symbol(void *kptr, struct save_ctx *ctx)
 111 {
 112         char *buf = ctx->save_buf;
 113         int size = sizeof(ctx->save_buf);
 114
 115         if (symcache == NULL ||
 116            (char *)kptr < symbegin || (char *)kptr >= symend
 117         ) {
 118                 snprintf(buf, size, "%p", kptr);
 119                 return(buf);
 120         }
 121         while ((char *)symcache->symaddr < (char *)kptr) {
 122                 if (TAILQ_NEXT(symcache, link) == NULL)
 123                         break;
 124                 symcache = TAILQ_NEXT(symcache, link);
 125         }
 126         while ((char *)symcache->symaddr > (char *)kptr) {
 127                 if (symcache != TAILQ_FIRST(&symlist))
 128                         symcache = TAILQ_PREV(symcache, symlist, link);
 129         }
 130         snprintf(buf, size, "%s+%d", symcache->symname,
 131                 (int)((char *)kptr - symcache->symaddr));
 132         return(buf);
 133 }