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, 2008, 2009, 2010, 2011
6 Free Software Foundation, Inc.
8 This file is part of GDB.
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3 of the License, or
13 (at your option) any later version.
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program. If not, see <http://www.gnu.org/licenses/>.
23 Contributed by Raoul M. Gough (RaoulGough@yahoo.co.uk). */
25 #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
);