summaryrefslogtreecommitdiffstats
path: root/libvpx/build/make/obj_int_extract.c
blob: 819ce9d587b0e7e73af5c95b5d73a67742ec2981 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
/*
 *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */


#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "vpx_config.h"
#include "vpx/vpx_integer.h"

typedef enum {
  OUTPUT_FMT_PLAIN,
  OUTPUT_FMT_RVDS,
  OUTPUT_FMT_GAS,
  OUTPUT_FMT_C_HEADER,
} output_fmt_t;

int log_msg(const char *fmt, ...) {
  int res;
  va_list ap;
  va_start(ap, fmt);
  res = vfprintf(stderr, fmt, ap);
  va_end(ap);
  return res;
}

#if defined(__GNUC__) && __GNUC__
#if defined(__MACH__)

#include <mach-o/loader.h>
#include <mach-o/nlist.h>

int print_macho_equ(output_fmt_t mode, uint8_t* name, int val) {
  switch (mode) {
    case OUTPUT_FMT_RVDS:
      printf("%-40s EQU %5d\n", name, val);
      return 0;
    case OUTPUT_FMT_GAS:
      printf(".set %-40s, %5d\n", name, val);
      return 0;
    case OUTPUT_FMT_C_HEADER:
      printf("#define %-40s %5d\n", name, val);
      return 0;
    default:
      log_msg("Unsupported mode: %d", mode);
      return 1;
  }
}

int parse_macho(uint8_t *base_buf, size_t sz, output_fmt_t mode) {
  int i, j;
  struct mach_header header;
  uint8_t *buf = base_buf;
  int base_data_section = 0;
  int bits = 0;

  /* We can read in mach_header for 32 and 64 bit architectures
   * because it's identical to mach_header_64 except for the last
   * element (uint32_t reserved), which we don't use. Then, when
   * we know which architecture we're looking at, increment buf
   * appropriately.
   */
  memcpy(&header, buf, sizeof(struct mach_header));

  if (header.magic == MH_MAGIC) {
    if (header.cputype == CPU_TYPE_ARM
        || header.cputype == CPU_TYPE_X86) {
      bits = 32;
      buf += sizeof(struct mach_header);
    } else {
      log_msg("Bad cputype for object file. Currently only tested for CPU_TYPE_[ARM|X86].\n");
      goto bail;
    }
  } else if (header.magic == MH_MAGIC_64) {
    if (header.cputype == CPU_TYPE_X86_64) {
      bits = 64;
      buf += sizeof(struct mach_header_64);
    } else {
      log_msg("Bad cputype for object file. Currently only tested for CPU_TYPE_X86_64.\n");
      goto bail;
    }
  } else {
    log_msg("Bad magic number for object file. 0x%x or 0x%x expected, 0x%x found.\n",
            MH_MAGIC, MH_MAGIC_64, header.magic);
    goto bail;
  }

  if (header.filetype != MH_OBJECT) {
    log_msg("Bad filetype for object file. Currently only tested for MH_OBJECT.\n");
    goto bail;
  }

  for (i = 0; i < header.ncmds; i++) {
    struct load_command lc;

    memcpy(&lc, buf, sizeof(struct load_command));

    if (lc.cmd == LC_SEGMENT) {
      uint8_t *seg_buf = buf;
      struct section s;
      struct segment_command seg_c;

      memcpy(&seg_c, seg_buf, sizeof(struct segment_command));
      seg_buf += sizeof(struct segment_command);

      /* Although each section is given it's own offset, nlist.n_value
       * references the offset of the first section. This isn't
       * apparent without debug information because the offset of the
       * data section is the same as the first section. However, with
       * debug sections mixed in, the offset of the debug section
       * increases but n_value still references the first section.
       */
      if (seg_c.nsects < 1) {
        log_msg("Not enough sections\n");
        goto bail;
      }

      memcpy(&s, seg_buf, sizeof(struct section));
      base_data_section = s.offset;
    } else if (lc.cmd == LC_SEGMENT_64) {
      uint8_t *seg_buf = buf;
      struct section_64 s;
      struct segment_command_64 seg_c;

      memcpy(&seg_c, seg_buf, sizeof(struct segment_command_64));
      seg_buf += sizeof(struct segment_command_64);

      /* Explanation in LG_SEGMENT */
      if (seg_c.nsects < 1) {
        log_msg("Not enough sections\n");
        goto bail;
      }

      memcpy(&s, seg_buf, sizeof(struct section_64));
      base_data_section = s.offset;
    } else if (lc.cmd == LC_SYMTAB) {
      if (base_data_section != 0) {
        struct symtab_command sc;
        uint8_t *sym_buf = base_buf;
        uint8_t *str_buf = base_buf;

        memcpy(&sc, buf, sizeof(struct symtab_command));

        if (sc.cmdsize != sizeof(struct symtab_command)) {
          log_msg("Can't find symbol table!\n");
          goto bail;
        }

        sym_buf += sc.symoff;
        str_buf += sc.stroff;

        for (j = 0; j < sc.nsyms; j++) {
          /* Location of string is cacluated each time from the
           * start of the string buffer.  On darwin the symbols
           * are prefixed by "_", so we bump the pointer by 1.
           * The target value is defined as an int in *_asm_*_offsets.c,
           * which is 4 bytes on all targets we currently use.
           */
          if (bits == 32) {
            struct nlist nl;
            int val;

            memcpy(&nl, sym_buf, sizeof(struct nlist));
            sym_buf += sizeof(struct nlist);

            memcpy(&val, base_buf + base_data_section + nl.n_value,
                   sizeof(val));
            print_macho_equ(mode, str_buf + nl.n_un.n_strx + 1, val);
          } else { /* if (bits == 64) */
            struct nlist_64 nl;
            int val;

            memcpy(&nl, sym_buf, sizeof(struct nlist_64));
            sym_buf += sizeof(struct nlist_64);

            memcpy(&val, base_buf + base_data_section + nl.n_value,
                   sizeof(val));
            print_macho_equ(mode, str_buf + nl.n_un.n_strx + 1, val);
          }
        }
      }
    }

    buf += lc.cmdsize;
  }

  return 0;
bail:
  return 1;

}

#elif defined(__ELF__)
#include "elf.h"

#define COPY_STRUCT(dst, buf, ofst, sz) do {\
    if(ofst + sizeof((*(dst))) > sz) goto bail;\
    memcpy(dst, buf+ofst, sizeof((*(dst))));\
  } while(0)

#define ENDIAN_ASSIGN(val, memb) do {\
    if(!elf->le_data) {log_msg("Big Endian data not supported yet!\n");goto bail;}\
    (val) = (memb);\
  } while(0)

#define ENDIAN_ASSIGN_IN_PLACE(memb) do {\
    ENDIAN_ASSIGN(memb, memb);\
  } while(0)

typedef struct {
  uint8_t      *buf; /* Buffer containing ELF data */
  size_t        sz;  /* Buffer size */
  int           le_data; /* Data is little-endian */
  unsigned char e_ident[EI_NIDENT]; /* Magic number and other info */
  int           bits; /* 32 or 64 */
  Elf32_Ehdr    hdr32;
  Elf64_Ehdr    hdr64;
} elf_obj_t;

int parse_elf_header(elf_obj_t *elf) {
  int res;
  /* Verify ELF Magic numbers */
  COPY_STRUCT(&elf->e_ident, elf->buf, 0, elf->sz);
  res = elf->e_ident[EI_MAG0] == ELFMAG0;
  res &= elf->e_ident[EI_MAG1] == ELFMAG1;
  res &= elf->e_ident[EI_MAG2] == ELFMAG2;
  res &= elf->e_ident[EI_MAG3] == ELFMAG3;
  res &= elf->e_ident[EI_CLASS] == ELFCLASS32
         || elf->e_ident[EI_CLASS] == ELFCLASS64;
  res &= elf->e_ident[EI_DATA] == ELFDATA2LSB;

  if (!res) goto bail;

  elf->le_data = elf->e_ident[EI_DATA] == ELFDATA2LSB;

  /* Read in relevant values */
  if (elf->e_ident[EI_CLASS] == ELFCLASS32) {
    elf->bits = 32;
    COPY_STRUCT(&elf->hdr32, elf->buf, 0, elf->sz);

    ENDIAN_ASSIGN_IN_PLACE(elf->hdr32.e_type);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr32.e_machine);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr32.e_version);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr32.e_entry);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr32.e_phoff);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr32.e_shoff);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr32.e_flags);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr32.e_ehsize);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr32.e_phentsize);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr32.e_phnum);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr32.e_shentsize);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr32.e_shnum);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr32.e_shstrndx);
  } else { /* if (elf->e_ident[EI_CLASS] == ELFCLASS64) */
    elf->bits = 64;
    COPY_STRUCT(&elf->hdr64, elf->buf, 0, elf->sz);

    ENDIAN_ASSIGN_IN_PLACE(elf->hdr64.e_type);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr64.e_machine);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr64.e_version);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr64.e_entry);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr64.e_phoff);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr64.e_shoff);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr64.e_flags);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr64.e_ehsize);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr64.e_phentsize);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr64.e_phnum);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr64.e_shentsize);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr64.e_shnum);
    ENDIAN_ASSIGN_IN_PLACE(elf->hdr64.e_shstrndx);
  }

  return 0;
bail:
  log_msg("Failed to parse ELF file header");
  return 1;
}

int parse_elf_section(elf_obj_t *elf, int idx, Elf32_Shdr *hdr32, Elf64_Shdr *hdr64) {
  if (hdr32) {
    if (idx >= elf->hdr32.e_shnum)
      goto bail;

    COPY_STRUCT(hdr32, elf->buf, elf->hdr32.e_shoff + idx * elf->hdr32.e_shentsize,
                elf->sz);
    ENDIAN_ASSIGN_IN_PLACE(hdr32->sh_name);
    ENDIAN_ASSIGN_IN_PLACE(hdr32->sh_type);
    ENDIAN_ASSIGN_IN_PLACE(hdr32->sh_flags);
    ENDIAN_ASSIGN_IN_PLACE(hdr32->sh_addr);
    ENDIAN_ASSIGN_IN_PLACE(hdr32->sh_offset);
    ENDIAN_ASSIGN_IN_PLACE(hdr32->sh_size);
    ENDIAN_ASSIGN_IN_PLACE(hdr32->sh_link);
    ENDIAN_ASSIGN_IN_PLACE(hdr32->sh_info);
    ENDIAN_ASSIGN_IN_PLACE(hdr32->sh_addralign);
    ENDIAN_ASSIGN_IN_PLACE(hdr32->sh_entsize);
  } else { /* if (hdr64) */
    if (idx >= elf->hdr64.e_shnum)
      goto bail;

    COPY_STRUCT(hdr64, elf->buf, elf->hdr64.e_shoff + idx * elf->hdr64.e_shentsize,
                elf->sz);
    ENDIAN_ASSIGN_IN_PLACE(hdr64->sh_name);
    ENDIAN_ASSIGN_IN_PLACE(hdr64->sh_type);
    ENDIAN_ASSIGN_IN_PLACE(hdr64->sh_flags);
    ENDIAN_ASSIGN_IN_PLACE(hdr64->sh_addr);
    ENDIAN_ASSIGN_IN_PLACE(hdr64->sh_offset);
    ENDIAN_ASSIGN_IN_PLACE(hdr64->sh_size);
    ENDIAN_ASSIGN_IN_PLACE(hdr64->sh_link);
    ENDIAN_ASSIGN_IN_PLACE(hdr64->sh_info);
    ENDIAN_ASSIGN_IN_PLACE(hdr64->sh_addralign);
    ENDIAN_ASSIGN_IN_PLACE(hdr64->sh_entsize);
  }

  return 0;
bail:
  return 1;
}

const char *parse_elf_string_table(elf_obj_t *elf, int s_idx, int idx) {
  if (elf->bits == 32) {
    Elf32_Shdr shdr;

    if (parse_elf_section(elf, s_idx, &shdr, NULL)) {
      log_msg("Failed to parse ELF string table: section %d, index %d\n",
              s_idx, idx);
      return "";
    }

    return (char *)(elf->buf + shdr.sh_offset + idx);
  } else { /* if (elf->bits == 64) */
    Elf64_Shdr shdr;

    if (parse_elf_section(elf, s_idx, NULL, &shdr)) {
      log_msg("Failed to parse ELF string table: section %d, index %d\n",
              s_idx, idx);
      return "";
    }

    return (char *)(elf->buf + shdr.sh_offset + idx);
  }
}

int parse_elf_symbol(elf_obj_t *elf, unsigned int ofst, Elf32_Sym *sym32, Elf64_Sym *sym64) {
  if (sym32) {
    COPY_STRUCT(sym32, elf->buf, ofst, elf->sz);
    ENDIAN_ASSIGN_IN_PLACE(sym32->st_name);
    ENDIAN_ASSIGN_IN_PLACE(sym32->st_value);
    ENDIAN_ASSIGN_IN_PLACE(sym32->st_size);
    ENDIAN_ASSIGN_IN_PLACE(sym32->st_info);
    ENDIAN_ASSIGN_IN_PLACE(sym32->st_other);
    ENDIAN_ASSIGN_IN_PLACE(sym32->st_shndx);
  } else { /* if (sym64) */
    COPY_STRUCT(sym64, elf->buf, ofst, elf->sz);
    ENDIAN_ASSIGN_IN_PLACE(sym64->st_name);
    ENDIAN_ASSIGN_IN_PLACE(sym64->st_value);
    ENDIAN_ASSIGN_IN_PLACE(sym64->st_size);
    ENDIAN_ASSIGN_IN_PLACE(sym64->st_info);
    ENDIAN_ASSIGN_IN_PLACE(sym64->st_other);
    ENDIAN_ASSIGN_IN_PLACE(sym64->st_shndx);
  }
  return 0;
bail:
  return 1;
}

int parse_elf(uint8_t *buf, size_t sz, output_fmt_t mode) {
  elf_obj_t    elf;
  unsigned int ofst;
  int          i;
  Elf32_Off    strtab_off32;
  Elf64_Off    strtab_off64; /* save String Table offset for later use */

  memset(&elf, 0, sizeof(elf));
  elf.buf = buf;
  elf.sz = sz;

  /* Parse Header */
  if (parse_elf_header(&elf))
    goto bail;

  if (elf.bits == 32) {
    Elf32_Shdr shdr;
    for (i = 0; i < elf.hdr32.e_shnum; i++) {
      parse_elf_section(&elf, i, &shdr, NULL);

      if (shdr.sh_type == SHT_STRTAB) {
        char strtsb_name[128];

        strcpy(strtsb_name, (char *)(elf.buf + shdr.sh_offset + shdr.sh_name));

        if (!(strcmp(strtsb_name, ".shstrtab"))) {
          /* log_msg("found section: %s\n", strtsb_name); */
          strtab_off32 = shdr.sh_offset;
          break;
        }
      }
    }
  } else { /* if (elf.bits == 64) */
    Elf64_Shdr shdr;
    for (i = 0; i < elf.hdr64.e_shnum; i++) {
      parse_elf_section(&elf, i, NULL, &shdr);

      if (shdr.sh_type == SHT_STRTAB) {
        char strtsb_name[128];

        strcpy(strtsb_name, (char *)(elf.buf + shdr.sh_offset + shdr.sh_name));

        if (!(strcmp(strtsb_name, ".shstrtab"))) {
          /* log_msg("found section: %s\n", strtsb_name); */
          strtab_off64 = shdr.sh_offset;
          break;
        }
      }
    }
  }

  /* Parse all Symbol Tables */
  if (elf.bits == 32) {
    Elf32_Shdr shdr;
    for (i = 0; i < elf.hdr32.e_shnum; i++) {
      parse_elf_section(&elf, i, &shdr, NULL);

      if (shdr.sh_type == SHT_SYMTAB) {
        for (ofst = shdr.sh_offset;
             ofst < shdr.sh_offset + shdr.sh_size;
             ofst += shdr.sh_entsize) {
          Elf32_Sym sym;

          parse_elf_symbol(&elf, ofst, &sym, NULL);

          /* For all OBJECTS (data objects), extract the value from the
           * proper data segment.
           */
          /* if (ELF32_ST_TYPE(sym.st_info) == STT_OBJECT && sym.st_name)
              log_msg("found data object %s\n",
                      parse_elf_string_table(&elf,
                                             shdr.sh_link,
                                             sym.st_name));
           */

          if (ELF32_ST_TYPE(sym.st_info) == STT_OBJECT
              && sym.st_size == 4) {
            Elf32_Shdr dhdr;
            int val = 0;
            char section_name[128];

            parse_elf_section(&elf, sym.st_shndx, &dhdr, NULL);

            /* For explanition - refer to _MSC_VER version of code */
            strcpy(section_name, (char *)(elf.buf + strtab_off32 + dhdr.sh_name));
            /* log_msg("Section_name: %s, Section_type: %d\n", section_name, dhdr.sh_type); */

            if (strcmp(section_name, ".bss")) {
              if (sizeof(val) != sym.st_size) {
                /* The target value is declared as an int in
                 * *_asm_*_offsets.c, which is 4 bytes on all
                 * targets we currently use. Complain loudly if
                 * this is not true.
                 */
                log_msg("Symbol size is wrong\n");
                goto bail;
              }

              memcpy(&val,
                     elf.buf + dhdr.sh_offset + sym.st_value,
                     sym.st_size);
            }

            if (!elf.le_data) {
              log_msg("Big Endian data not supported yet!\n");
              goto bail;
            }

            switch (mode) {
              case OUTPUT_FMT_RVDS:
                printf("%-40s EQU %5d\n",
                       parse_elf_string_table(&elf,
                                              shdr.sh_link,
                                              sym.st_name),
                       val);
                break;
              case OUTPUT_FMT_GAS:
                printf(".equ %-40s, %5d\n",
                       parse_elf_string_table(&elf,
                                              shdr.sh_link,
                                              sym.st_name),
                       val);
                break;
              case OUTPUT_FMT_C_HEADER:
                printf("#define %-40s %5d\n",
                       parse_elf_string_table(&elf,
                                              shdr.sh_link,
                                              sym.st_name),
                       val);
                break;
              default:
                printf("%s = %d\n",
                       parse_elf_string_table(&elf,
                                              shdr.sh_link,
                                              sym.st_name),
                       val);
            }
          }
        }
      }
    }
  } else { /* if (elf.bits == 64) */
    Elf64_Shdr shdr;
    for (i = 0; i < elf.hdr64.e_shnum; i++) {
      parse_elf_section(&elf, i, NULL, &shdr);

      if (shdr.sh_type == SHT_SYMTAB) {
        for (ofst = shdr.sh_offset;
             ofst < shdr.sh_offset + shdr.sh_size;
             ofst += shdr.sh_entsize) {
          Elf64_Sym sym;

          parse_elf_symbol(&elf, ofst, NULL, &sym);

          /* For all OBJECTS (data objects), extract the value from the
           * proper data segment.
           */
          /* if (ELF64_ST_TYPE(sym.st_info) == STT_OBJECT && sym.st_name)
              log_msg("found data object %s\n",
                      parse_elf_string_table(&elf,
                                             shdr.sh_link,
                                             sym.st_name));
           */

          if (ELF64_ST_TYPE(sym.st_info) == STT_OBJECT
              && sym.st_size == 4) {
            Elf64_Shdr dhdr;
            int val = 0;
            char section_name[128];

            parse_elf_section(&elf, sym.st_shndx, NULL, &dhdr);

            /* For explanition - refer to _MSC_VER version of code */
            strcpy(section_name, (char *)(elf.buf + strtab_off64 + dhdr.sh_name));
            /* log_msg("Section_name: %s, Section_type: %d\n", section_name, dhdr.sh_type); */

            if ((strcmp(section_name, ".bss"))) {
              if (sizeof(val) != sym.st_size) {
                /* The target value is declared as an int in
                 * *_asm_*_offsets.c, which is 4 bytes on all
                 * targets we currently use. Complain loudly if
                 * this is not true.
                 */
                log_msg("Symbol size is wrong\n");
                goto bail;
              }

              memcpy(&val,
                     elf.buf + dhdr.sh_offset + sym.st_value,
                     sym.st_size);
            }

            if (!elf.le_data) {
              log_msg("Big Endian data not supported yet!\n");
              goto bail;
            }

            switch (mode) {
              case OUTPUT_FMT_RVDS:
                printf("%-40s EQU %5d\n",
                       parse_elf_string_table(&elf,
                                              shdr.sh_link,
                                              sym.st_name),
                       val);
                break;
              case OUTPUT_FMT_GAS:
                printf(".equ %-40s, %5d\n",
                       parse_elf_string_table(&elf,
                                              shdr.sh_link,
                                              sym.st_name),
                       val);
                break;
              default:
                printf("%s = %d\n",
                       parse_elf_string_table(&elf,
                                              shdr.sh_link,
                                              sym.st_name),
                       val);
            }
          }
        }
      }
    }
  }

  if (mode == OUTPUT_FMT_RVDS)
    printf("    END\n");

  return 0;
bail:
  log_msg("Parse error: File does not appear to be valid ELF32 or ELF64\n");
  return 1;
}

#endif
#endif /* defined(__GNUC__) && __GNUC__ */


#if defined(_MSC_VER) || defined(__MINGW32__) || defined(__CYGWIN__)
/*  See "Microsoft Portable Executable and Common Object File Format Specification"
    for reference.
*/
#define get_le32(x) ((*(x)) | (*(x+1)) << 8 |(*(x+2)) << 16 | (*(x+3)) << 24 )
#define get_le16(x) ((*(x)) | (*(x+1)) << 8)

int parse_coff(uint8_t *buf, size_t sz) {
  unsigned int nsections, symtab_ptr, symtab_sz, strtab_ptr;
  unsigned int sectionrawdata_ptr;
  unsigned int i;
  uint8_t *ptr;
  uint32_t symoffset;

  char **sectionlist;  // this array holds all section names in their correct order.
  // it is used to check if the symbol is in .bss or .rdata section.

  nsections = get_le16(buf + 2);
  symtab_ptr = get_le32(buf + 8);
  symtab_sz = get_le32(buf + 12);
  strtab_ptr = symtab_ptr + symtab_sz * 18;

  if (nsections > 96) {
    log_msg("Too many sections\n");
    return 1;
  }

  sectionlist = malloc(nsections * sizeof(sectionlist));

  if (sectionlist == NULL) {
    log_msg("Allocating first level of section list failed\n");
    return 1;
  }

  // log_msg("COFF: Found %u symbols in %u sections.\n", symtab_sz, nsections);

  /*
  The size of optional header is always zero for an obj file. So, the section header
  follows the file header immediately.
  */

  ptr = buf + 20;     // section header

  for (i = 0; i < nsections; i++) {
    char sectionname[9] = {0, 0, 0, 0, 0, 0, 0, 0, 0};
    strncpy(sectionname, ptr, 8);
    // log_msg("COFF: Parsing section %s\n",sectionname);

    sectionlist[i] = malloc(strlen(sectionname) + 1);

    if (sectionlist[i] == NULL) {
      log_msg("Allocating storage for %s failed\n", sectionname);
      goto bail;
    }
    strcpy(sectionlist[i], sectionname);

    // check if it's .rdata and is not a COMDAT section.
    if (!strcmp(sectionname, ".rdata") &&
        (get_le32(ptr + 36) & 0x1000) == 0) {
      sectionrawdata_ptr = get_le32(ptr + 20);
    }

    ptr += 40;
  }

  // log_msg("COFF: Symbol table at offset %u\n", symtab_ptr);
  // log_msg("COFF: raw data pointer ofset for section .rdata is %u\n", sectionrawdata_ptr);

  /*  The compiler puts the data with non-zero offset in .rdata section, but puts the data with
      zero offset in .bss section. So, if the data in in .bss section, set offset=0.
      Note from Wiki: In an object module compiled from C, the bss section contains
      the local variables (but not functions) that were declared with the static keyword,
      except for those with non-zero initial values. (In C, static variables are initialized
      to zero by default.) It also contains the non-local (both extern and static) variables
      that are also initialized to zero (either explicitly or by default).
      */
  // move to symbol table
  /* COFF symbol table:
      offset      field
      0           Name(*)
      8           Value
      12          SectionNumber
      14          Type
      16          StorageClass
      17          NumberOfAuxSymbols
      */
  ptr = buf + symtab_ptr;

  for (i = 0; i < symtab_sz; i++) {
    int16_t section = get_le16(ptr + 12); // section number

    if (section > 0 && ptr[16] == 2) {
      // if(section > 0 && ptr[16] == 3 && get_le32(ptr+8)) {

      if (get_le32(ptr)) {
        char name[9] = {0, 0, 0, 0, 0, 0, 0, 0, 0};
        strncpy(name, ptr, 8);
        // log_msg("COFF: Parsing symbol %s\n",name);
        /* The 64bit Windows compiler doesn't prefix with an _.
         * Check what's there, and bump if necessary
         */
        if (name[0] == '_')
          printf("%-40s EQU ", name + 1);
        else
          printf("%-40s EQU ", name);
      } else {
        // log_msg("COFF: Parsing symbol %s\n",
        //        buf + strtab_ptr + get_le32(ptr+4));
        if ((buf + strtab_ptr + get_le32(ptr + 4))[0] == '_')
          printf("%-40s EQU ",
                 buf + strtab_ptr + get_le32(ptr + 4) + 1);
        else
          printf("%-40s EQU ", buf + strtab_ptr + get_le32(ptr + 4));
      }

      if (!(strcmp(sectionlist[section - 1], ".bss"))) {
        symoffset = 0;
      } else {
        symoffset = get_le32(buf + sectionrawdata_ptr + get_le32(ptr + 8));
      }

      // log_msg("      Section: %d\n",section);
      // log_msg("      Class:   %d\n",ptr[16]);
      // log_msg("      Address: %u\n",get_le32(ptr+8));
      // log_msg("      Offset: %u\n", symoffset);

      printf("%5d\n", symoffset);
    }

    ptr += 18;
  }

  printf("    END\n");

  for (i = 0; i < nsections; i++) {
    free(sectionlist[i]);
  }

  free(sectionlist);

  return 0;
bail:

  for (i = 0; i < nsections; i++) {
    free(sectionlist[i]);
  }

  free(sectionlist);

  return 1;
}
#endif /* defined(_MSC_VER) || defined(__MINGW32__) || defined(__CYGWIN__) */

int main(int argc, char **argv) {
  output_fmt_t mode = OUTPUT_FMT_PLAIN;
  const char *f;
  uint8_t *file_buf;
  int res;
  FILE *fp;
  long int file_size;

  if (argc < 2 || argc > 3) {
    fprintf(stderr, "Usage: %s [output format] <obj file>\n\n", argv[0]);
    fprintf(stderr, "  <obj file>\tobject file to parse\n");
    fprintf(stderr, "Output Formats:\n");
    fprintf(stderr, "  gas  - compatible with GNU assembler\n");
    fprintf(stderr, "  rvds - compatible with armasm\n");
    fprintf(stderr, "  cheader - c/c++ header file\n");
    goto bail;
  }

  f = argv[2];

  if (!strcmp(argv[1], "rvds"))
    mode = OUTPUT_FMT_RVDS;
  else if (!strcmp(argv[1], "gas"))
    mode = OUTPUT_FMT_GAS;
  else if (!strcmp(argv[1], "cheader"))
    mode = OUTPUT_FMT_C_HEADER;
  else
    f = argv[1];

  fp = fopen(f, "rb");

  if (!fp) {
    perror("Unable to open file");
    goto bail;
  }

  if (fseek(fp, 0, SEEK_END)) {
    perror("stat");
    goto bail;
  }

  file_size = ftell(fp);
  file_buf = malloc(file_size);

  if (!file_buf) {
    perror("malloc");
    goto bail;
  }

  rewind(fp);

  if (fread(file_buf, sizeof(char), file_size, fp) != file_size) {
    perror("read");
    goto bail;
  }

  if (fclose(fp)) {
    perror("close");
    goto bail;
  }

#if defined(__GNUC__) && __GNUC__
#if defined(__MACH__)
  res = parse_macho(file_buf, file_size, mode);
#elif defined(__ELF__)
  res = parse_elf(file_buf, file_size, mode);
#endif
#endif
#if defined(_MSC_VER) || defined(__MINGW32__) || defined(__CYGWIN__)
  res = parse_coff(file_buf, file_size);
#endif

  free(file_buf);

  if (!res)
    return EXIT_SUCCESS;

bail:
  return EXIT_FAILURE;
}