xref: /netbsd-src/external/gpl3/gdb.old/dist/gdb/coff-pe-read.c (revision b2c35e17b976cf7ccd7250c86c6f5e95090ed636)
1 /* Read the export table symbols from a portable executable and
2    convert to internal format, for GDB. Used as a last resort if no
3    debugging symbols recognized.
4 
5    Copyright (C) 2003-2020 Free Software Foundation, Inc.
6 
7    This file is part of GDB.
8 
9    This program is free software; you can redistribute it and/or modify
10    it under the terms of the GNU General Public License as published by
11    the Free Software Foundation; either version 3 of the License, or
12    (at your option) any later version.
13 
14    This program is distributed in the hope that it will be useful,
15    but WITHOUT ANY WARRANTY; without even the implied warranty of
16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17    GNU General Public License for more details.
18 
19    You should have received a copy of the GNU General Public License
20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
21 
22    Contributed by Raoul M. Gough (RaoulGough@yahoo.co.uk).  */
23 
24 #include "defs.h"
25 
26 #include "coff-pe-read.h"
27 
28 #include "bfd.h"
29 #include "gdbtypes.h"
30 
31 #include "command.h"
32 #include "gdbcmd.h"
33 #include "symtab.h"
34 #include "symfile.h"
35 #include "objfiles.h"
36 #include "gdbsupport/common-utils.h"
37 #include "coff/internal.h"
38 
39 #include <ctype.h>
40 
41 /* Internal section information */
42 
43 /* Coff PE read debugging flag:
44    default value is 0,
45    value 1 outputs problems encountered while parsing PE file,
46    value above 1 also lists all generated minimal symbols.  */
47 static unsigned int debug_coff_pe_read;
48 
49 struct read_pe_section_data
50 {
51   CORE_ADDR vma_offset;		/* Offset to loaded address of section.  */
52   unsigned long rva_start;	/* Start offset within the pe.  */
53   unsigned long rva_end;	/* End offset within the pe.  */
54   enum minimal_symbol_type ms_type;	/* Type to assign symbols in
55 					   section.  */
56   unsigned int index;		/* BFD section number.  */
57   std::string section_name;	/* Recorded section name.  */
58 };
59 
60 #define IMAGE_SCN_CNT_CODE 0x20
61 #define IMAGE_SCN_CNT_INITIALIZED_DATA 0x40
62 #define IMAGE_SCN_CNT_UNINITIALIZED_DATA 0x80
63 #define PE_SECTION_INDEX_TEXT     0
64 #define PE_SECTION_INDEX_DATA     1
65 #define PE_SECTION_INDEX_BSS      2
66 #define PE_SECTION_TABLE_SIZE     3
67 #define PE_SECTION_INDEX_INVALID -1
68 
69 /* Get the index of the named section in our own array, which contains
70    text, data and bss in that order.  Return PE_SECTION_INDEX_INVALID
71    if passed an unrecognised section name.  */
72 
73 static int
74 read_pe_section_index (const char *section_name)
75 {
76   if (strcmp (section_name, ".text") == 0)
77     {
78       return PE_SECTION_INDEX_TEXT;
79     }
80 
81   else if (strcmp (section_name, ".data") == 0)
82     {
83       return PE_SECTION_INDEX_DATA;
84     }
85 
86   else if (strcmp (section_name, ".bss") == 0)
87     {
88       return PE_SECTION_INDEX_BSS;
89     }
90 
91   else
92     {
93       return PE_SECTION_INDEX_INVALID;
94     }
95 }
96 
97 /* Get the index of the named section in our own full array.
98    text, data and bss in that order.  Return PE_SECTION_INDEX_INVALID
99    if passed an unrecognised section name.  */
100 
101 static int
102 get_pe_section_index (const char *section_name,
103 		      struct read_pe_section_data *sections,
104 		      int nb_sections)
105 {
106   int i;
107 
108   for (i = 0; i < nb_sections; i++)
109     if (sections[i].section_name == section_name)
110       return i;
111   return PE_SECTION_INDEX_INVALID;
112 }
113 
114 /* Structure used by get_section_vmas function below
115    to access section_data array and the size of the array
116    stored in nb_sections field.  */
117 struct pe_sections_info
118 {
119   int nb_sections;
120   struct read_pe_section_data *sections;
121 };
122 
123 /* Record the virtual memory address of a section.  */
124 
125 static void
126 get_section_vmas (bfd *abfd, asection *sectp, void *context)
127 {
128   struct pe_sections_info *data = (struct pe_sections_info *) context;
129   struct read_pe_section_data *sections = data->sections;
130   int sectix = get_pe_section_index (sectp->name, sections,
131 				     data->nb_sections);
132 
133   if (sectix != PE_SECTION_INDEX_INVALID)
134     {
135       /* Data within the section start at rva_start in the pe and at
136          bfd_get_section_vma() within memory.  Store the offset.  */
137 
138       sections[sectix].vma_offset
139 	= bfd_section_vma (sectp) - sections[sectix].rva_start;
140     }
141 }
142 
143 /* Create a minimal symbol entry for an exported symbol.
144    SYM_NAME contains the exported name or NULL if exported by ordinal,
145    FUNC_RVA contains the Relative Virtual Address of the symbol,
146    ORDINAL is the ordinal index value of the symbol,
147    SECTION_DATA contains information about the section in which the
148    symbol is declared,
149    DLL_NAME is the internal name of the DLL file,
150    OBJFILE is the objfile struct of DLL_NAME.  */
151 
152 static void
153 add_pe_exported_sym (minimal_symbol_reader &reader,
154 		     const char *sym_name,
155 		     unsigned long func_rva,
156 		     int ordinal,
157 		     const struct read_pe_section_data *section_data,
158 		     const char *dll_name, struct objfile *objfile)
159 {
160   /* Add the stored offset to get the loaded address of the symbol.  */
161   CORE_ADDR vma = func_rva + section_data->vma_offset;
162 
163   /* Generate a (hopefully unique) qualified name using the first part
164      of the dll name, e.g. KERNEL32!AddAtomA.  This matches the style
165      used by windbg from the "Microsoft Debugging Tools for Windows".  */
166 
167   std::string bare_name;
168   if (sym_name == NULL || *sym_name == '\0')
169     bare_name = string_printf ("#%d", ordinal);
170   else
171     bare_name = sym_name;
172 
173   std::string qualified_name
174     = string_printf ("%s!%s", dll_name, bare_name.c_str ());
175 
176   if ((section_data->ms_type == mst_unknown) && debug_coff_pe_read)
177     fprintf_unfiltered (gdb_stdlog , _("Unknown section type for \"%s\""
178 			" for entry \"%s\" in dll \"%s\"\n"),
179 			section_data->section_name.c_str (), sym_name,
180 			dll_name);
181 
182   reader.record_with_info (qualified_name.c_str (), vma, section_data->ms_type,
183 			   section_data->index);
184 
185   /* Enter the plain name as well, which might not be unique.  */
186   reader.record_with_info (bare_name.c_str (), vma, section_data->ms_type,
187 			   section_data->index);
188   if (debug_coff_pe_read > 1)
189     fprintf_unfiltered (gdb_stdlog, _("Adding exported symbol \"%s\""
190 			" in dll \"%s\"\n"), sym_name, dll_name);
191 }
192 
193 /* Create a minimal symbol entry for an exported forward symbol.
194    Return 1 if the forwarded function was found 0 otherwise.
195    SYM_NAME contains the exported name or NULL if exported by ordinal,
196    FORWARD_DLL_NAME is the name of the DLL in which the target symobl resides,
197    FORWARD_FUNC_NAME is the name of the target symbol in that DLL,
198    ORDINAL is the ordinal index value of the symbol,
199    DLL_NAME is the internal name of the DLL file,
200    OBJFILE is the objfile struct of DLL_NAME.  */
201 
202 static int
203 add_pe_forwarded_sym (minimal_symbol_reader &reader,
204 		      const char *sym_name, const char *forward_dll_name,
205 		      const char *forward_func_name, int ordinal,
206 		      const char *dll_name, struct objfile *objfile)
207 {
208   CORE_ADDR vma, baseaddr;
209   struct bound_minimal_symbol msymbol;
210   enum minimal_symbol_type msymtype;
211   int forward_dll_name_len = strlen (forward_dll_name);
212   int forward_func_name_len = strlen (forward_func_name);
213   int forward_len = forward_dll_name_len + forward_func_name_len + 2;
214   char *forward_qualified_name = (char *) alloca (forward_len);
215   short section;
216 
217   xsnprintf (forward_qualified_name, forward_len, "%s!%s", forward_dll_name,
218 	     forward_func_name);
219 
220 
221   msymbol = lookup_bound_minimal_symbol (forward_qualified_name);
222 
223   if (!msymbol.minsym)
224     {
225       int i;
226 
227       for (i = 0; i < forward_dll_name_len; i++)
228 	forward_qualified_name[i] = tolower (forward_qualified_name[i]);
229       msymbol = lookup_bound_minimal_symbol (forward_qualified_name);
230     }
231 
232   if (!msymbol.minsym)
233     {
234       if (debug_coff_pe_read)
235 	fprintf_unfiltered (gdb_stdlog, _("Unable to find function \"%s\" in"
236 			    " dll \"%s\", forward of \"%s\" in dll \"%s\"\n"),
237 			    forward_func_name, forward_dll_name, sym_name,
238 			    dll_name);
239       return 0;
240     }
241 
242   if (debug_coff_pe_read > 1)
243     fprintf_unfiltered (gdb_stdlog, _("Adding forwarded exported symbol"
244 			" \"%s\" in dll \"%s\", pointing to \"%s\"\n"),
245 			sym_name, dll_name, forward_qualified_name);
246 
247   vma = BMSYMBOL_VALUE_ADDRESS (msymbol);
248   msymtype = MSYMBOL_TYPE (msymbol.minsym);
249   section = MSYMBOL_SECTION (msymbol.minsym);
250 
251   /* Generate a (hopefully unique) qualified name using the first part
252      of the dll name, e.g. KERNEL32!AddAtomA.  This matches the style
253      used by windbg from the "Microsoft Debugging Tools for Windows".  */
254 
255   std::string bare_name;
256   if (sym_name == NULL || *sym_name == '\0')
257     bare_name = string_printf ("#%d", ordinal);
258   else
259     bare_name = sym_name;
260 
261   std::string qualified_name
262     = string_printf ("%s!%s", dll_name, bare_name.c_str ());
263 
264   /* Note that this code makes a minimal symbol whose value may point
265      outside of any section in this objfile.  These symbols can't
266      really be relocated properly, but nevertheless we make a stab at
267      it, choosing an approach consistent with the history of this
268      code.  */
269   baseaddr = objfile->text_section_offset ();
270 
271   reader.record_with_info (qualified_name.c_str (), vma - baseaddr, msymtype,
272 			   section);
273 
274   /* Enter the plain name as well, which might not be unique.  */
275   reader.record_with_info (bare_name.c_str(), vma - baseaddr, msymtype,
276 			   section);
277 
278   return 1;
279 }
280 
281 /* Truncate a dll_name at the last dot character.  */
282 
283 static void
284 read_pe_truncate_name (char *dll_name)
285 {
286   char *last_point = strrchr (dll_name, '.');
287 
288   if (last_point != NULL)
289     *last_point = '\0';
290 }
291 
292 /* Low-level support functions, direct from the ld module pe-dll.c.  */
293 static unsigned int
294 pe_get16 (bfd *abfd, int where)
295 {
296   unsigned char b[2];
297 
298   bfd_seek (abfd, (file_ptr) where, SEEK_SET);
299   bfd_bread (b, (bfd_size_type) 2, abfd);
300   return b[0] + (b[1] << 8);
301 }
302 
303 static unsigned int
304 pe_get32 (bfd *abfd, int where)
305 {
306   unsigned char b[4];
307 
308   bfd_seek (abfd, (file_ptr) where, SEEK_SET);
309   bfd_bread (b, (bfd_size_type) 4, abfd);
310   return b[0] + (b[1] << 8) + (b[2] << 16) + (b[3] << 24);
311 }
312 
313 static unsigned int
314 pe_as16 (void *ptr)
315 {
316   unsigned char *b = (unsigned char *) ptr;
317 
318   return b[0] + (b[1] << 8);
319 }
320 
321 static unsigned int
322 pe_as32 (void *ptr)
323 {
324   unsigned char *b = (unsigned char *) ptr;
325 
326   return b[0] + (b[1] << 8) + (b[2] << 16) + (b[3] << 24);
327 }
328 
329 /* Read the (non-debug) export symbol table from a portable
330    executable.  Code originally lifted from the ld function
331    pe_implied_import_dll in pe-dll.c.  */
332 
333 void
334 read_pe_exported_syms (minimal_symbol_reader &reader,
335 		       struct objfile *objfile)
336 {
337   bfd *dll = objfile->obfd;
338   unsigned long nbnormal, nbforward;
339   unsigned long pe_header_offset, opthdr_ofs, num_entries, i;
340   unsigned long export_opthdrrva, export_opthdrsize;
341   unsigned long export_rva, export_size, nsections, secptr, expptr;
342   unsigned long exp_funcbase;
343   unsigned char *expdata, *erva;
344   unsigned long name_rvas, ordinals, nexp, ordbase;
345   char *dll_name = (char *) bfd_get_filename (dll);
346   int otherix = PE_SECTION_TABLE_SIZE;
347   int is_pe64 = 0;
348   int is_pe32 = 0;
349 
350   /* Array elements are for text, data and bss in that order
351      Initialization with RVA_START > RVA_END guarantees that
352      unused sections won't be matched.  */
353   struct pe_sections_info pe_sections_info;
354 
355   char const *target = bfd_get_target (objfile->obfd);
356 
357   std::vector<struct read_pe_section_data> section_data
358     (PE_SECTION_TABLE_SIZE);
359 
360   for (i=0; i < PE_SECTION_TABLE_SIZE; i++)
361     {
362       section_data[i].vma_offset = 0;
363       section_data[i].rva_start = 1;
364       section_data[i].rva_end = 0;
365     };
366   section_data[PE_SECTION_INDEX_TEXT].ms_type = mst_text;
367   section_data[PE_SECTION_INDEX_TEXT].section_name = ".text";
368   section_data[PE_SECTION_INDEX_DATA].ms_type = mst_data;
369   section_data[PE_SECTION_INDEX_DATA].section_name = ".data";
370   section_data[PE_SECTION_INDEX_BSS].ms_type = mst_bss;
371   section_data[PE_SECTION_INDEX_BSS].section_name = ".bss";
372 
373   is_pe64 = (strcmp (target, "pe-x86-64") == 0
374 	     || strcmp (target, "pei-x86-64") == 0);
375   is_pe32 = (strcmp (target, "pe-i386") == 0
376 	     || strcmp (target, "pei-i386") == 0
377 	     || strcmp (target, "pe-arm-wince-little") == 0
378 	     || strcmp (target, "pei-arm-wince-little") == 0);
379   if (!is_pe32 && !is_pe64)
380     {
381       /* This is not a recognized PE format file.  Abort now, because
382 	 the code is untested on anything else.  *FIXME* test on
383 	 further architectures and loosen or remove this test.  */
384       return;
385     }
386 
387   /* Get pe_header, optional header and numbers of export entries.  */
388   pe_header_offset = pe_get32 (dll, 0x3c);
389   opthdr_ofs = pe_header_offset + 4 + 20;
390   if (is_pe64)
391     num_entries = pe_get32 (dll, opthdr_ofs + 108);
392   else
393     num_entries = pe_get32 (dll, opthdr_ofs + 92);
394 
395   if (num_entries < 1)		/* No exports.  */
396     return;
397   if (is_pe64)
398     {
399       export_opthdrrva = pe_get32 (dll, opthdr_ofs + 112);
400       export_opthdrsize = pe_get32 (dll, opthdr_ofs + 116);
401     }
402   else
403     {
404       export_opthdrrva = pe_get32 (dll, opthdr_ofs + 96);
405       export_opthdrsize = pe_get32 (dll, opthdr_ofs + 100);
406     }
407   nsections = pe_get16 (dll, pe_header_offset + 4 + 2);
408   secptr = (pe_header_offset + 4 + 20 +
409 	    pe_get16 (dll, pe_header_offset + 4 + 16));
410   expptr = 0;
411   export_size = 0;
412 
413   /* Get the rva and size of the export section.  */
414   for (i = 0; i < nsections; i++)
415     {
416       char sname[8];
417       unsigned long secptr1 = secptr + 40 * i;
418       unsigned long vaddr = pe_get32 (dll, secptr1 + 12);
419       unsigned long vsize = pe_get32 (dll, secptr1 + 16);
420       unsigned long fptr = pe_get32 (dll, secptr1 + 20);
421 
422       bfd_seek (dll, (file_ptr) secptr1, SEEK_SET);
423       bfd_bread (sname, (bfd_size_type) sizeof (sname), dll);
424 
425       if ((strcmp (sname, ".edata") == 0)
426 	  || (vaddr <= export_opthdrrva && export_opthdrrva < vaddr + vsize))
427 	{
428 	  if (strcmp (sname, ".edata") != 0)
429 	    {
430 	      if (debug_coff_pe_read)
431 		fprintf_unfiltered (gdb_stdlog, _("Export RVA for dll "
432 				    "\"%s\" is in section \"%s\"\n"),
433 				    dll_name, sname);
434 	    }
435 	  else if (export_opthdrrva != vaddr && debug_coff_pe_read)
436 	    fprintf_unfiltered (gdb_stdlog, _("Wrong value of export RVA"
437 				" for dll \"%s\": 0x%lx instead of 0x%lx\n"),
438 				dll_name, export_opthdrrva, vaddr);
439 	  expptr = fptr + (export_opthdrrva - vaddr);
440 	  break;
441 	}
442     }
443 
444   if (expptr == 0)
445     {
446       /* no section contains export table rva */
447       return;
448     }
449 
450   export_rva = export_opthdrrva;
451   export_size = export_opthdrsize;
452 
453   if (export_size == 0)
454     {
455       /* Empty export table.  */
456       return;
457     }
458 
459   /* Scan sections and store the base and size of the relevant
460      sections.  */
461   for (i = 0; i < nsections; i++)
462     {
463       unsigned long secptr1 = secptr + 40 * i;
464       unsigned long vsize = pe_get32 (dll, secptr1 + 8);
465       unsigned long vaddr = pe_get32 (dll, secptr1 + 12);
466       unsigned long characteristics = pe_get32 (dll, secptr1 + 36);
467       char sec_name[SCNNMLEN + 1];
468       int sectix;
469       unsigned int bfd_section_index;
470       asection *section;
471 
472       bfd_seek (dll, (file_ptr) secptr1 + 0, SEEK_SET);
473       bfd_bread (sec_name, (bfd_size_type) SCNNMLEN, dll);
474       sec_name[SCNNMLEN] = '\0';
475 
476       sectix = read_pe_section_index (sec_name);
477       section = bfd_get_section_by_name (dll, sec_name);
478       if (section)
479 	bfd_section_index = section->index;
480       else
481 	bfd_section_index = -1;
482 
483       if (sectix != PE_SECTION_INDEX_INVALID)
484 	{
485 	  section_data[sectix].rva_start = vaddr;
486 	  section_data[sectix].rva_end = vaddr + vsize;
487 	  section_data[sectix].index = bfd_section_index;
488 	}
489       else
490 	{
491 	  section_data.resize (otherix + 1);
492 	  section_data[otherix].section_name = sec_name;
493 	  section_data[otherix].rva_start = vaddr;
494 	  section_data[otherix].rva_end = vaddr + vsize;
495 	  section_data[otherix].vma_offset = 0;
496 	  section_data[otherix].index = bfd_section_index;
497 	  if (characteristics & IMAGE_SCN_CNT_CODE)
498 	    section_data[otherix].ms_type = mst_text;
499 	  else if (characteristics & IMAGE_SCN_CNT_INITIALIZED_DATA)
500 	    section_data[otherix].ms_type = mst_data;
501 	  else if (characteristics & IMAGE_SCN_CNT_UNINITIALIZED_DATA)
502 	    section_data[otherix].ms_type = mst_bss;
503 	  else
504 	    section_data[otherix].ms_type = mst_unknown;
505 	  otherix++;
506 	}
507     }
508 
509   gdb::def_vector<unsigned char> expdata_storage (export_size);
510   expdata = expdata_storage.data ();
511 
512   bfd_seek (dll, (file_ptr) expptr, SEEK_SET);
513   bfd_bread (expdata, (bfd_size_type) export_size, dll);
514   erva = expdata - export_rva;
515 
516   nexp = pe_as32 (expdata + 24);
517   name_rvas = pe_as32 (expdata + 32);
518   ordinals = pe_as32 (expdata + 36);
519   ordbase = pe_as32 (expdata + 16);
520   exp_funcbase = pe_as32 (expdata + 28);
521 
522   /* Use internal dll name instead of full pathname.  */
523   dll_name = (char *) (pe_as32 (expdata + 12) + erva);
524 
525   pe_sections_info.nb_sections = otherix;
526   pe_sections_info.sections = section_data.data ();
527 
528   bfd_map_over_sections (dll, get_section_vmas, &pe_sections_info);
529 
530   /* Truncate name at first dot. Should maybe also convert to all
531      lower case for convenience on Windows.  */
532   read_pe_truncate_name (dll_name);
533 
534   if (debug_coff_pe_read)
535     fprintf_unfiltered (gdb_stdlog, _("DLL \"%s\" has %ld export entries,"
536 			" base=%ld\n"), dll_name, nexp, ordbase);
537   nbforward = 0;
538   nbnormal = 0;
539   /* Iterate through the list of symbols.  */
540   for (i = 0; i < nexp; i++)
541     {
542       /* Pointer to the names vector.  */
543       unsigned long name_rva = pe_as32 (erva + name_rvas + i * 4);
544       /* Retrieve ordinal value.  */
545 
546       unsigned long ordinal = pe_as16 (erva + ordinals + i * 2);
547 
548 
549       /* Pointer to the function address vector.  */
550       /* This is relative to ordinal value. */
551       unsigned long func_rva = pe_as32 (erva + exp_funcbase +
552                                         ordinal * 4);
553 
554       /* Find this symbol's section in our own array.  */
555       int sectix = 0;
556       int section_found = 0;
557 
558       /* First handle forward cases.  */
559       if (func_rva >= export_rva && func_rva < export_rva + export_size)
560 	{
561 	  char *forward_name = (char *) (erva + func_rva);
562 	  char *funcname = (char *) (erva + name_rva);
563 	  char *forward_dll_name = forward_name;
564 	  char *forward_func_name = forward_name;
565 	  char *sep = strrchr (forward_name, '.');
566 
567 	  if (sep)
568 	    {
569 	      int len = (int) (sep - forward_name);
570 
571 	      forward_dll_name = (char *) alloca (len + 1);
572 	      strncpy (forward_dll_name, forward_name, len);
573 	      forward_dll_name[len] = '\0';
574 	      forward_func_name = ++sep;
575 	    }
576 	  if (add_pe_forwarded_sym (reader, funcname, forward_dll_name,
577 				    forward_func_name, ordinal,
578 				    dll_name, objfile) != 0)
579 	    ++nbforward;
580 	  continue;
581 	}
582 
583       for (sectix = 0; sectix < otherix; ++sectix)
584 	{
585 	  if ((func_rva >= section_data[sectix].rva_start)
586 	      && (func_rva < section_data[sectix].rva_end))
587 	    {
588 	      char *sym_name = (char *) (erva + name_rva);
589 
590 	      section_found = 1;
591 	      add_pe_exported_sym (reader, sym_name, func_rva, ordinal,
592 				   &section_data[sectix], dll_name, objfile);
593 	      ++nbnormal;
594 	      break;
595 	    }
596 	}
597       if (!section_found)
598 	{
599 	  char *funcname = (char *) (erva + name_rva);
600 
601 	  if (name_rva == 0)
602 	    {
603 	      add_pe_exported_sym (reader, NULL, func_rva, ordinal,
604 				   &section_data[0], dll_name, objfile);
605 	      ++nbnormal;
606 	    }
607 	  else if (debug_coff_pe_read)
608 	    fprintf_unfiltered (gdb_stdlog, _("Export name \"%s\" ord. %lu,"
609 				" RVA 0x%lx in dll \"%s\" not handled\n"),
610 				funcname, ordinal, func_rva, dll_name);
611 	}
612     }
613 
614   if (debug_coff_pe_read)
615     fprintf_unfiltered (gdb_stdlog, _("Finished reading \"%s\", exports %ld,"
616 			" forwards %ld, total %ld/%ld.\n"), dll_name, nbnormal,
617 			nbforward, nbnormal + nbforward, nexp);
618 }
619 
620 /* Extract from ABFD the offset of the .text section.
621    This offset is mainly related to the offset within the file.
622    The value was previously expected to be 0x1000 for all files,
623    but some Windows OS core DLLs seem to use 0x10000 section alignment
624    which modified the return value of that function.
625    Still return default 0x1000 value if ABFD is NULL or
626    if '.text' section is not found, but that should not happen...  */
627 
628 #define DEFAULT_COFF_PE_TEXT_SECTION_OFFSET 0x1000
629 
630 CORE_ADDR
631 pe_text_section_offset (struct bfd *abfd)
632 
633 {
634   unsigned long pe_header_offset, i;
635   unsigned long nsections, secptr;
636   int is_pe64 = 0;
637   int is_pe32 = 0;
638   char const *target;
639 
640   if (!abfd)
641     return DEFAULT_COFF_PE_TEXT_SECTION_OFFSET;
642 
643   target = bfd_get_target (abfd);
644 
645   is_pe64 = (strcmp (target, "pe-x86-64") == 0
646 	     || strcmp (target, "pei-x86-64") == 0);
647   is_pe32 = (strcmp (target, "pe-i386") == 0
648 	     || strcmp (target, "pei-i386") == 0
649 	     || strcmp (target, "pe-arm-wince-little") == 0
650 	     || strcmp (target, "pei-arm-wince-little") == 0);
651 
652   if (!is_pe32 && !is_pe64)
653     {
654       /* This is not a recognized PE format file.  Abort now, because
655 	 the code is untested on anything else.  *FIXME* test on
656 	 further architectures and loosen or remove this test.  */
657       return DEFAULT_COFF_PE_TEXT_SECTION_OFFSET;
658     }
659 
660   /* Get pe_header, optional header and numbers of sections.  */
661   pe_header_offset = pe_get32 (abfd, 0x3c);
662   nsections = pe_get16 (abfd, pe_header_offset + 4 + 2);
663   secptr = (pe_header_offset + 4 + 20 +
664 	    pe_get16 (abfd, pe_header_offset + 4 + 16));
665 
666   /* Get the rva and size of the export section.  */
667   for (i = 0; i < nsections; i++)
668     {
669       char sname[SCNNMLEN + 1];
670       unsigned long secptr1 = secptr + 40 * i;
671       unsigned long vaddr = pe_get32 (abfd, secptr1 + 12);
672 
673       bfd_seek (abfd, (file_ptr) secptr1, SEEK_SET);
674       bfd_bread (sname, (bfd_size_type) SCNNMLEN, abfd);
675       sname[SCNNMLEN] = '\0';
676       if (strcmp (sname, ".text") == 0)
677 	return vaddr;
678     }
679 
680   return DEFAULT_COFF_PE_TEXT_SECTION_OFFSET;
681 }
682 
683 /* Implements "show debug coff_pe_read" command.  */
684 
685 static void
686 show_debug_coff_pe_read (struct ui_file *file, int from_tty,
687 			 struct cmd_list_element *c, const char *value)
688 {
689   fprintf_filtered (file, _("Coff PE read debugging is %s.\n"), value);
690 }
691 
692 /* Adds "Set/show debug coff_pe_read" commands.  */
693 
694 void _initialize_coff_pe_read ();
695 void
696 _initialize_coff_pe_read ()
697 {
698   add_setshow_zuinteger_cmd ("coff-pe-read", class_maintenance,
699 			     &debug_coff_pe_read,
700 			     _("Set coff PE read debugging."),
701 			     _("Show coff PE read debugging."),
702 			     _("When set, debugging messages for coff reading "
703 			       "of exported symbols are displayed."),
704 			     NULL, show_debug_coff_pe_read,
705 			     &setdebuglist, &showdebuglist);
706 }
707