gen/nlist.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  *
  27  *
  28  * Redistribution and use in source and binary forms, with or without
  29  * modification, are permitted provided that the following conditions
  30  * are met:
  31  * 1. Redistributions of source code must retain the above copyright
  32  *    notice, this list of conditions and the following disclaimer.
  33  * 2. Redistributions in binary form must reproduce the above copyright
  34  *    notice, this list of conditions and the following disclaimer in the
  35  *    documentation and/or other materials provided with the distribution.
  36  * 3. All advertising materials mentioning features or use of this software
  37  *    must display the following acknowledgement:
  38  *      This product includes software developed by the University of
  39  *      California, Berkeley and its contributors.
  40  * 4. Neither the name of the University nor the names of its contributors
  41  *    may be used to endorse or promote products derived from this software
  42  *    without specific prior written permission.
  43  *
  44  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  45  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  46  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  47  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  48  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  49  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  50  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  51  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  52  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  53  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  54  * SUCH DAMAGE.
  55  */
  56
  57
  58 #include <stdlib.h>
  59 #include <sys/types.h>
  60 #include <sys/file.h>
  61 #include <fcntl.h>
  62 #include <string.h>
  63 #include <unistd.h>
  64
  65 /* Stuff lifted from <a.out.h> and <sys/exec.h> since they are gone */
  66 /*
  67  * Header prepended to each a.out file.
  68  */
  69 struct exec {
  70 unsigned short  a_machtype;     /* machine type */
  71 unsigned short  a_magic;        /* magic number */
  72 unsigned long   a_text;         /* size of text segment */
  73 unsigned long   a_data;         /* size of initialized data */
  74 unsigned long   a_bss;          /* size of uninitialized data */
  75 unsigned long   a_syms;         /* size of symbol table */
  76 unsigned long   a_entry;        /* entry point */
  77 unsigned long   a_trsize;       /* size of text relocation */
  78 unsigned long   a_drsize;       /* size of data relocation */
  79 };
  80
  81 #define OMAGIC  0407            /* old impure format */
  82 #define NMAGIC  0410            /* read-only text */
  83 #define ZMAGIC  0413            /* demand load format */
  84
  85 #define N_BADMAG(x) \
  86     (((x).a_magic)!=OMAGIC && ((x).a_magic)!=NMAGIC && ((x).a_magic)!=ZMAGIC)
  87 #define N_TXTOFF(x) \
  88         ((x).a_magic==ZMAGIC ? 0 : sizeof (struct exec))
  89 #define N_SYMOFF(x) \
  90         (N_TXTOFF(x) + (x).a_text+(x).a_data + (x).a_trsize+(x).a_drsize)
  91
  92 #include <mach/mach.h>
  93 #include <mach-o/nlist.h>
  94 #include <stdio.h>
  95 #include <mach-o/loader.h>
  96 #include <mach-o/fat.h>
  97
  98 /*
  99  * CPUSUBTYPE_SUPPORT should be changed to non-zero once the
 100  * cpusubtype_* routines are available in libc.
 101  */
 102 #define CPUSUBTYPE_SUPPORT      0
 103
 104 /*
 105  * nlist - retreive attributes from name list (string table version)
 106  */
 107
 108 int
 109 nlist(name, list)
 110         const char *name;
 111         struct nlist *list;
 112 {
 113         int fd, n;
 114
 115         fd = open(name, O_RDONLY, 0);
 116         if (fd < 0)
 117                 return (-1);
 118         n = __fdnlist(fd, list);
 119         (void)close(fd);
 120         return (n);
 121 }
 122
 123 /* Note: __fdnlist() is called from kvm_nlist in libkvm's kvm.c */
 124
 125 int
 126 __fdnlist(fd, list)
 127         int fd;
 128         struct nlist *list;
 129 {
 130         register struct nlist *p, *q;
 131         register char *s1, *s2;
 132         register n, m;
 133         int maxlen, nreq;
 134         off_t sa;               /* symbol address */
 135         off_t ss;               /* start of strings */
 136         struct exec buf;
 137         struct nlist space[BUFSIZ/sizeof (struct nlist)];
 138         unsigned  arch_offset = 0;
 139
 140         maxlen = 0;
 141         for (q = list, nreq = 0; q->n_un.n_name && q->n_un.n_name[0]; q++, nreq++) {
 142                 q->n_type = 0;
 143                 q->n_value = 0;
 144                 q->n_desc = 0;
 145                 q->n_sect = 0;
 146                 n = strlen(q->n_un.n_name);
 147                 if (n > maxlen)
 148                         maxlen = n;
 149         }
 150         if (read(fd, (char *)&buf, sizeof(buf)) != sizeof(buf) ||
 151             (N_BADMAG(buf) && *((long *)&buf) != MH_MAGIC &&
 152              NXSwapBigLongToHost(*((long *)&buf)) != FAT_MAGIC)) {
 153                 return (-1);
 154         }
 155
 156         /* Deal with fat file if necessary */
 157         if (NXSwapBigLongToHost(*((long *)&buf)) == FAT_MAGIC) {
 158                 struct host_basic_info hbi;
 159                 struct fat_header fh;
 160                 struct fat_arch *fat_archs, *fap;
 161                 unsigned i;
 162                 host_t host;
 163
 164                 /* Get our host info */
 165                 host = mach_host_self();
 166                 i = HOST_BASIC_INFO_COUNT;
 167                 if (host_info(host, HOST_BASIC_INFO,
 168                               (host_info_t)(&hbi), &i) != KERN_SUCCESS) {
 169                         return (-1);
 170                 }
 171                 mach_port_deallocate(mach_task_self(), host);
 172
 173                 /* Read in the fat header */
 174                 lseek(fd, 0, SEEK_SET);
 175                 if (read(fd, (char *)&fh, sizeof(fh)) != sizeof(fh)) {
 176                         return (-1);
 177                 }
 178
 179                 /* Convert fat_narchs to host byte order */
 180                 fh.nfat_arch = NXSwapBigLongToHost(fh.nfat_arch);
 181
 182                 /* Read in the fat archs */
 183                 fat_archs = (struct fat_arch *)malloc(fh.nfat_arch *
 184                                                       sizeof(struct fat_arch));
 185                 if (fat_archs == NULL) {
 186                         return (-1);
 187                 }
 188                 if (read(fd, (char *)fat_archs,
 189                          sizeof(struct fat_arch) * fh.nfat_arch) !=
 190                     sizeof(struct fat_arch) * fh.nfat_arch) {
 191                         free(fat_archs);
 192                         return (-1);
 193                 }
 194
 195                 /*
 196                  * Convert archs to host byte ordering (a constraint of
 197                  * cpusubtype_getbestarch()
 198                  */
 199                 for (i = 0; i < fh.nfat_arch; i++) {
 200                         fat_archs[i].cputype =
 201                                 NXSwapBigLongToHost(fat_archs[i].cputype);
 202                         fat_archs[i].cpusubtype =
 203                               NXSwapBigLongToHost(fat_archs[i].cpusubtype);
 204                         fat_archs[i].offset =
 205                                 NXSwapBigLongToHost(fat_archs[i].offset);
 206                         fat_archs[i].size =
 207                                 NXSwapBigLongToHost(fat_archs[i].size);
 208                         fat_archs[i].align =
 209                                 NXSwapBigLongToHost(fat_archs[i].align);
 210                 }
 211
 212 #if     CPUSUBTYPE_SUPPORT
 213                 fap = cpusubtype_getbestarch(hbi.cpu_type, hbi.cpu_subtype,
 214                                              fat_archs, fh.nfat_arch);
 215 #else   CPUSUBTYPE_SUPPORT
 216 #warning        Use the cpusubtype functions!!!
 217                 fap = NULL;
 218                 for (i = 0; i < fh.nfat_arch; i++) {
 219                         if (fat_archs[i].cputype == hbi.cpu_type) {
 220                                 fap = &fat_archs[i];
 221                                 break;
 222                         }
 223                 }
 224 #endif  CPUSUBTYPE_SUPPORT
 225                 if (!fap) {
 226                         free(fat_archs);
 227                         return (-1);
 228                 }
 229                 arch_offset = fap->offset;
 230                 free(fat_archs);
 231
 232                 /* Read in the beginning of the architecture-specific file */
 233                 lseek(fd, arch_offset, SEEK_SET);
 234                 if (read(fd, (char *)&buf, sizeof(buf)) != sizeof(buf)) {
 235                         return (-1);
 236                 }
 237         }
 238
 239         if (*((long *)&buf) == MH_MAGIC) {
 240             struct mach_header mh;
 241             struct load_command *load_commands, *lcp;
 242             struct symtab_command *stp;
 243             long i;
 244
 245                 lseek(fd, arch_offset, SEEK_SET);
 246                 if (read(fd, (char *)&mh, sizeof(mh)) != sizeof(mh)) {
 247                         return (-1);
 248                 }
 249                 load_commands = (struct load_command *)malloc(mh.sizeofcmds);
 250                 if (load_commands == NULL) {
 251                         return (-1);
 252                 }
 253                 if (read(fd, (char *)load_commands, mh.sizeofcmds) !=
 254                     mh.sizeofcmds) {
 255                         free(load_commands);
 256                         return (-1);
 257                 }
 258                 stp = NULL;
 259                 lcp = load_commands;
 260                 for (i = 0; i < mh.ncmds; i++) {
 261                         if (lcp->cmdsize % sizeof(long) != 0 ||
 262                             lcp->cmdsize <= 0 ||
 263                             (char *)lcp + lcp->cmdsize >
 264                             (char *)load_commands + mh.sizeofcmds) {
 265                                 free(load_commands);
 266                                 return (-1);
 267                         }
 268                         if (lcp->cmd == LC_SYMTAB) {
 269                                 if (lcp->cmdsize !=
 270                                    sizeof(struct symtab_command)) {
 271                                         free(load_commands);
 272                                         return (-1);
 273                                 }
 274                                 stp = (struct symtab_command *)lcp;
 275                                 break;
 276                         }
 277                         lcp = (struct load_command *)
 278                               ((char *)lcp + lcp->cmdsize);
 279                 }
 280                 if (stp == NULL) {
 281                         free(load_commands);
 282                         return (-1);
 283                 }
 284                 sa = stp->symoff + arch_offset;
 285                 ss = stp->stroff + arch_offset;
 286                 n = stp->nsyms * sizeof(struct nlist);
 287                 free(load_commands);
 288         }
 289         else {
 290                 sa = N_SYMOFF(buf) + arch_offset;
 291                 ss = sa + buf.a_syms + arch_offset;
 292                 n = buf.a_syms;
 293         }
 294
 295         lseek(fd, sa, SEEK_SET);
 296         while (n) {
 297                 long savpos;
 298
 299                 m = sizeof (space);
 300                 if (n < m)
 301                         m = n;
 302                 if (read(fd, (char *)space, m) != m)
 303                         break;
 304                 n -= m;
 305                 savpos = lseek(fd, 0, SEEK_CUR);
 306                 for (q = space; (m -= sizeof(struct nlist)) >= 0; q++) {
 307                         char nambuf[BUFSIZ];
 308
 309                         if (q->n_un.n_strx == 0 || q->n_type & N_STAB)
 310                                 continue;
 311                         lseek(fd, ss+q->n_un.n_strx, SEEK_SET);
 312                         read(fd, nambuf, maxlen+1);
 313                         for (p = list; p->n_un.n_name && p->n_un.n_name[0]; p++) {
 314                                 s1 = p->n_un.n_name;
 315                                 s2 = nambuf;
 316                                 while (*s1) {
 317                                         if (*s1++ != *s2++)
 318                                                 goto cont;
 319                                 }
 320                                 if (*s2)
 321                                         goto cont;
 322                                 p->n_value = q->n_value;
 323                                 p->n_type = q->n_type;
 324                                 p->n_desc = q->n_desc;
 325                                 p->n_sect = q->n_sect;
 326                                 if (--nreq == 0)
 327                                         return (nreq);
 328                                 break;
 329                 cont:           ;
 330                         }
 331                 }
 332                 lseek(fd, savpos, SEEK_SET);
 333         }
 334         return (nreq);
 335 }