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.
5 Copyright (C) 2003, 2007-2012 Free Software Foundation, Inc.
7 This file is part of GDB.
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.
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.
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/>.
22 Contributed by Raoul M. Gough (RaoulGough@yahoo.co.uk). */
26 #include "coff-pe-read.h"
35 /* Internal section information */
37 struct read_pe_section_data
39 CORE_ADDR vma_offset; /* Offset to loaded address of section. */
40 unsigned long rva_start; /* Start offset within the pe. */
41 unsigned long rva_end; /* End offset within the pe. */
42 enum minimal_symbol_type ms_type; /* Type to assign symbols in
46 #define PE_SECTION_INDEX_TEXT 0
47 #define PE_SECTION_INDEX_DATA 1
48 #define PE_SECTION_INDEX_BSS 2
49 #define PE_SECTION_TABLE_SIZE 3
50 #define PE_SECTION_INDEX_INVALID -1
52 /* Get the index of the named section in our own array, which contains
53 text, data and bss in that order. Return PE_SECTION_INDEX_INVALID
54 if passed an unrecognised section name. */
57 read_pe_section_index (const char *section_name)
59 if (strcmp (section_name, ".text") == 0)
61 return PE_SECTION_INDEX_TEXT;
64 else if (strcmp (section_name, ".data") == 0)
66 return PE_SECTION_INDEX_DATA;
69 else if (strcmp (section_name, ".bss") == 0)
71 return PE_SECTION_INDEX_BSS;
76 return PE_SECTION_INDEX_INVALID;
80 /* Record the virtual memory address of a section. */
83 get_section_vmas (bfd *abfd, asection *sectp, void *context)
85 struct read_pe_section_data *sections = context;
86 int sectix = read_pe_section_index (sectp->name);
88 if (sectix != PE_SECTION_INDEX_INVALID)
90 /* Data within the section start at rva_start in the pe and at
91 bfd_get_section_vma() within memory. Store the offset. */
93 sections[sectix].vma_offset
94 = bfd_get_section_vma (abfd, sectp) - sections[sectix].rva_start;
98 /* Create a minimal symbol entry for an exported symbol. */
101 add_pe_exported_sym (char *sym_name,
102 unsigned long func_rva,
103 const struct read_pe_section_data *section_data,
104 const char *dll_name, struct objfile *objfile)
106 /* Add the stored offset to get the loaded address of the symbol. */
108 CORE_ADDR vma = func_rva + section_data->vma_offset;
110 char *qualified_name = 0;
111 int dll_name_len = strlen (dll_name);
113 /* Generate a (hopefully unique) qualified name using the first part
114 of the dll name, e.g. KERNEL32!AddAtomA. This matches the style
115 used by windbg from the "Microsoft Debugging Tools for Windows". */
117 qualified_name = xmalloc (dll_name_len + strlen (sym_name) + 2);
119 strncpy (qualified_name, dll_name, dll_name_len);
120 qualified_name[dll_name_len] = '!';
121 strcpy (qualified_name + dll_name_len + 1, sym_name);
123 prim_record_minimal_symbol (qualified_name,
124 vma, section_data->ms_type, objfile);
126 xfree (qualified_name);
128 /* Enter the plain name as well, which might not be unique. */
129 prim_record_minimal_symbol (sym_name, vma,
130 section_data->ms_type, objfile);
133 /* Truncate a dll_name at the first dot character. */
136 read_pe_truncate_name (char *dll_name)
140 if ((*dll_name) == '.')
142 *dll_name = '\0'; /* truncates and causes loop exit. */
152 /* Low-level support functions, direct from the ld module pe-dll.c. */
154 pe_get16 (bfd *abfd, int where)
158 bfd_seek (abfd, (file_ptr) where, SEEK_SET);
159 bfd_bread (b, (bfd_size_type) 2, abfd);
160 return b[0] + (b[1] << 8);
164 pe_get32 (bfd *abfd, int where)
168 bfd_seek (abfd, (file_ptr) where, SEEK_SET);
169 bfd_bread (b, (bfd_size_type) 4, abfd);
170 return b[0] + (b[1] << 8) + (b[2] << 16) + (b[3] << 24);
176 unsigned char *b = ptr;
178 return b[0] + (b[1] << 8) + (b[2] << 16) + (b[3] << 24);
181 /* Read the (non-debug) export symbol table from a portable
182 executable. Code originally lifted from the ld function
183 pe_implied_import_dll in pe-dll.c. */
186 read_pe_exported_syms (struct objfile *objfile)
188 bfd *dll = objfile->obfd;
189 unsigned long pe_header_offset, opthdr_ofs, num_entries, i;
190 unsigned long export_rva, export_size, nsections, secptr, expptr;
191 unsigned long exp_funcbase;
192 unsigned char *expdata, *erva;
193 unsigned long name_rvas, ordinals, nexp, ordbase;
198 /* Array elements are for text, data and bss in that order
199 Initialization with start_rva > end_rva guarantees that
200 unused sections won't be matched. */
201 struct read_pe_section_data section_data[PE_SECTION_TABLE_SIZE]
202 = { {0, 1, 0, mst_text},
207 struct cleanup *back_to = 0;
209 char const *target = bfd_get_target (objfile->obfd);
211 is_pe64 = (strcmp (target, "pe-x86-64") == 0
212 || strcmp (target, "pei-x86-64") == 0);
213 is_pe32 = (strcmp (target, "pe-i386") == 0
214 || strcmp (target, "pei-i386") == 0
215 || strcmp (target, "pe-arm-wince-little") == 0
216 || strcmp (target, "pei-arm-wince-little") == 0);
218 if (!is_pe32 && !is_pe64)
220 /* This is not a recognized PE format file. Abort now, because
221 the code is untested on anything else. *FIXME* test on
222 further architectures and loosen or remove this test. */
226 /* Get pe_header, optional header and numbers of export entries. */
227 pe_header_offset = pe_get32 (dll, 0x3c);
228 opthdr_ofs = pe_header_offset + 4 + 20;
230 num_entries = pe_get32 (dll, opthdr_ofs + 108);
232 num_entries = pe_get32 (dll, opthdr_ofs + 92);
234 if (num_entries < 1) /* No exports. */
241 export_rva = pe_get32 (dll, opthdr_ofs + 112);
242 export_size = pe_get32 (dll, opthdr_ofs + 116);
246 export_rva = pe_get32 (dll, opthdr_ofs + 96);
247 export_size = pe_get32 (dll, opthdr_ofs + 100);
249 nsections = pe_get16 (dll, pe_header_offset + 4 + 2);
250 secptr = (pe_header_offset + 4 + 20 +
251 pe_get16 (dll, pe_header_offset + 4 + 16));
254 /* Get the rva and size of the export section. */
255 for (i = 0; i < nsections; i++)
258 unsigned long secptr1 = secptr + 40 * i;
259 unsigned long vaddr = pe_get32 (dll, secptr1 + 12);
260 unsigned long vsize = pe_get32 (dll, secptr1 + 16);
261 unsigned long fptr = pe_get32 (dll, secptr1 + 20);
263 bfd_seek (dll, (file_ptr) secptr1, SEEK_SET);
264 bfd_bread (sname, (bfd_size_type) 8, dll);
266 if (vaddr <= export_rva && vaddr + vsize > export_rva)
268 expptr = fptr + (export_rva - vaddr);
269 if (export_rva + export_size > vaddr + vsize)
270 export_size = vsize - (export_rva - vaddr);
275 if (export_size == 0)
277 /* Empty export table. */
281 /* Scan sections and store the base and size of the relevant
283 for (i = 0; i < nsections; i++)
285 unsigned long secptr1 = secptr + 40 * i;
286 unsigned long vsize = pe_get32 (dll, secptr1 + 8);
287 unsigned long vaddr = pe_get32 (dll, secptr1 + 12);
292 bfd_seek (dll, (file_ptr) secptr1 + 0, SEEK_SET);
293 bfd_bread (sec_name, (bfd_size_type) 8, dll);
295 sectix = read_pe_section_index (sec_name);
297 if (sectix != PE_SECTION_INDEX_INVALID)
299 section_data[sectix].rva_start = vaddr;
300 section_data[sectix].rva_end = vaddr + vsize;
304 expdata = (unsigned char *) xmalloc (export_size);
305 back_to = make_cleanup (xfree, expdata);
307 bfd_seek (dll, (file_ptr) expptr, SEEK_SET);
308 bfd_bread (expdata, (bfd_size_type) export_size, dll);
309 erva = expdata - export_rva;
311 nexp = pe_as32 (expdata + 24);
312 name_rvas = pe_as32 (expdata + 32);
313 ordinals = pe_as32 (expdata + 36);
314 ordbase = pe_as32 (expdata + 16);
315 exp_funcbase = pe_as32 (expdata + 28);
317 /* Use internal dll name instead of full pathname. */
318 dll_name = pe_as32 (expdata + 12) + erva;
320 bfd_map_over_sections (dll, get_section_vmas, section_data);
322 /* Adjust the vma_offsets in case this PE got relocated. This
323 assumes that *all* sections share the same relocation offset
324 as the text section. */
325 for (i = 0; i < PE_SECTION_TABLE_SIZE; i++)
327 section_data[i].vma_offset
328 += ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));
331 /* Truncate name at first dot. Should maybe also convert to all
332 lower case for convenience on Windows. */
333 read_pe_truncate_name (dll_name);
335 /* Iterate through the list of symbols. */
336 for (i = 0; i < nexp; i++)
338 /* Pointer to the names vector. */
339 unsigned long name_rva = pe_as32 (erva + name_rvas + i * 4);
341 /* Pointer to the function address vector. */
342 unsigned long func_rva = pe_as32 (erva + exp_funcbase + i * 4);
344 /* Find this symbol's section in our own array. */
347 for (sectix = 0; sectix < PE_SECTION_TABLE_SIZE; ++sectix)
349 if ((func_rva >= section_data[sectix].rva_start)
350 && (func_rva < section_data[sectix].rva_end))
352 add_pe_exported_sym (erva + name_rva,
354 section_data + sectix, dll_name, objfile);
360 /* Discard expdata. */
361 do_cleanups (back_to);