| File: | src/gnu/usr.bin/binutils/gdb/coff-pe-read.c |
| Warning: | line 295, column 3 Value stored to 'ordbase' is never read |
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| 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 2003 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 2 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, write to the Free Software |
| 21 | Foundation, Inc., 59 Temple Place - Suite 330, |
| 22 | Boston, MA 02111-1307, USA. |
| 23 | |
| 24 | Contributed by Raoul M. Gough (RaoulGough@yahoo.co.uk). */ |
| 25 | |
| 26 | #include "coff-pe-read.h" |
| 27 | |
| 28 | #include "bfd.h" |
| 29 | |
| 30 | #include "defs.h" |
| 31 | #include "gdbtypes.h" |
| 32 | |
| 33 | #include "symtab.h" |
| 34 | #include "symfile.h" |
| 35 | #include "objfiles.h" |
| 36 | |
| 37 | /* Internal section information */ |
| 38 | |
| 39 | struct read_pe_section_data |
| 40 | { |
| 41 | CORE_ADDR vma_offset; /* Offset to loaded address of section. */ |
| 42 | unsigned long rva_start; /* Start offset within the pe. */ |
| 43 | unsigned long rva_end; /* End offset within the pe. */ |
| 44 | enum minimal_symbol_type ms_type; /* Type to assign symbols in section. */ |
| 45 | }; |
| 46 | |
| 47 | #define PE_SECTION_INDEX_TEXT0 0 |
| 48 | #define PE_SECTION_INDEX_DATA1 1 |
| 49 | #define PE_SECTION_INDEX_BSS2 2 |
| 50 | #define PE_SECTION_TABLE_SIZE3 3 |
| 51 | #define PE_SECTION_INDEX_INVALID-1 -1 |
| 52 | |
| 53 | /* Get the index of the named section in our own array, which contains |
| 54 | text, data and bss in that order. Return PE_SECTION_INDEX_INVALID |
| 55 | if passed an unrecognised section name. */ |
| 56 | |
| 57 | static int |
| 58 | read_pe_section_index (const char *section_name) |
| 59 | { |
| 60 | if (strcmp (section_name, ".text") == 0) |
| 61 | { |
| 62 | return PE_SECTION_INDEX_TEXT0; |
| 63 | } |
| 64 | |
| 65 | else if (strcmp (section_name, ".data") == 0) |
| 66 | { |
| 67 | return PE_SECTION_INDEX_DATA1; |
| 68 | } |
| 69 | |
| 70 | else if (strcmp (section_name, ".bss") == 0) |
| 71 | { |
| 72 | return PE_SECTION_INDEX_BSS2; |
| 73 | } |
| 74 | |
| 75 | else |
| 76 | { |
| 77 | return PE_SECTION_INDEX_INVALID-1; |
| 78 | } |
| 79 | } |
| 80 | |
| 81 | /* Record the virtual memory address of a section. */ |
| 82 | |
| 83 | static void |
| 84 | get_section_vmas (bfd *abfd, asection *sectp, void *context) |
| 85 | { |
| 86 | struct read_pe_section_data *sections = context; |
| 87 | int sectix = read_pe_section_index (sectp->name); |
| 88 | |
| 89 | if (sectix != PE_SECTION_INDEX_INVALID-1) |
| 90 | { |
| 91 | /* Data within the section start at rva_start in the pe and at |
| 92 | bfd_get_section_vma() within memory. Store the offset. */ |
| 93 | |
| 94 | sections[sectix].vma_offset |
| 95 | = bfd_get_section_vma (abfd, sectp)((sectp)->vma + 0) - sections[sectix].rva_start; |
| 96 | } |
| 97 | } |
| 98 | |
| 99 | /* Create a minimal symbol entry for an exported symbol. */ |
| 100 | |
| 101 | static void |
| 102 | add_pe_exported_sym (char *sym_name, |
| 103 | unsigned long func_rva, |
| 104 | const struct read_pe_section_data *section_data, |
| 105 | const char *dll_name, struct objfile *objfile) |
| 106 | { |
| 107 | /* Add the stored offset to get the loaded address of the symbol. */ |
| 108 | |
| 109 | CORE_ADDR vma = func_rva + section_data->vma_offset; |
| 110 | |
| 111 | char *qualified_name = 0; |
| 112 | int dll_name_len = strlen (dll_name); |
| 113 | int count; |
| 114 | |
| 115 | /* Generate a (hopefully unique) qualified name using the first part |
| 116 | of the dll name, e.g. KERNEL32!AddAtomA. This matches the style |
| 117 | used by windbg from the "Microsoft Debugging Tools for Windows". */ |
| 118 | |
| 119 | qualified_name = xmalloc (dll_name_len + strlen (sym_name) + 2); |
| 120 | |
| 121 | strncpy (qualified_name, dll_name, dll_name_len); |
| 122 | qualified_name[dll_name_len] = '!'; |
| 123 | strcpy (qualified_name + dll_name_len + 1, sym_name); |
| 124 | |
| 125 | prim_record_minimal_symbol (qualified_name, |
| 126 | vma, section_data->ms_type, objfile); |
| 127 | |
| 128 | xfree (qualified_name); |
| 129 | |
| 130 | /* Enter the plain name as well, which might not be unique. */ |
| 131 | prim_record_minimal_symbol (sym_name, vma, section_data->ms_type, objfile); |
| 132 | } |
| 133 | |
| 134 | /* Truncate a dll_name at the first dot character. */ |
| 135 | |
| 136 | static void |
| 137 | read_pe_truncate_name (char *dll_name) |
| 138 | { |
| 139 | while (*dll_name) |
| 140 | { |
| 141 | if ((*dll_name) == '.') |
| 142 | { |
| 143 | *dll_name = '\0'; /* truncates and causes loop exit. */ |
| 144 | } |
| 145 | |
| 146 | else |
| 147 | { |
| 148 | ++dll_name; |
| 149 | } |
| 150 | } |
| 151 | } |
| 152 | |
| 153 | /* Low-level support functions, direct from the ld module pe-dll.c. */ |
| 154 | static unsigned int |
| 155 | pe_get16 (bfd *abfd, int where) |
| 156 | { |
| 157 | unsigned char b[2]; |
| 158 | |
| 159 | bfd_seek (abfd, (file_ptr) where, SEEK_SET0); |
| 160 | bfd_bread (b, (bfd_size_type) 2, abfd); |
| 161 | return b[0] + (b[1] << 8); |
| 162 | } |
| 163 | |
| 164 | static unsigned int |
| 165 | pe_get32 (bfd *abfd, int where) |
| 166 | { |
| 167 | unsigned char b[4]; |
| 168 | |
| 169 | bfd_seek (abfd, (file_ptr) where, SEEK_SET0); |
| 170 | bfd_bread (b, (bfd_size_type) 4, abfd); |
| 171 | return b[0] + (b[1] << 8) + (b[2] << 16) + (b[3] << 24); |
| 172 | } |
| 173 | |
| 174 | static unsigned int |
| 175 | pe_as32 (void *ptr) |
| 176 | { |
| 177 | unsigned char *b = ptr; |
| 178 | |
| 179 | return b[0] + (b[1] << 8) + (b[2] << 16) + (b[3] << 24); |
| 180 | } |
| 181 | |
| 182 | /* Read the (non-debug) export symbol table from a portable |
| 183 | executable. Code originally lifted from the ld function |
| 184 | pe_implied_import_dll in pe-dll.c. */ |
| 185 | |
| 186 | void |
| 187 | read_pe_exported_syms (struct objfile *objfile) |
| 188 | { |
| 189 | bfd *dll = objfile->obfd; |
| 190 | unsigned long pe_header_offset, opthdr_ofs, num_entries, i; |
| 191 | unsigned long export_rva, export_size, nsections, secptr, expptr; |
| 192 | unsigned long exp_funcbase; |
| 193 | unsigned char *expdata, *erva; |
| 194 | unsigned long name_rvas, ordinals, nexp, ordbase; |
| 195 | char *dll_name; |
| 196 | |
| 197 | /* Array elements are for text, data and bss in that order |
| 198 | Initialization with start_rva > end_rva guarantees that |
| 199 | unused sections won't be matched. */ |
| 200 | struct read_pe_section_data section_data[PE_SECTION_TABLE_SIZE3] |
| 201 | = { {0, 1, 0, mst_text}, |
| 202 | {0, 1, 0, mst_data}, |
| 203 | {0, 1, 0, mst_bss} |
| 204 | }; |
| 205 | |
| 206 | struct cleanup *back_to = 0; |
| 207 | |
| 208 | char const *target = bfd_get_target (objfile->obfd)((objfile->obfd)->xvec->name); |
| 209 | |
| 210 | if ((strcmp (target, "pe-i386") != 0) && (strcmp (target, "pei-i386") != 0)) |
| 211 | { |
| 212 | /* This is not an i386 format file. Abort now, because the code |
| 213 | is untested on anything else. *FIXME* test on further |
| 214 | architectures and loosen or remove this test. */ |
| 215 | return; |
| 216 | } |
| 217 | |
| 218 | /* Get pe_header, optional header and numbers of export entries. */ |
| 219 | pe_header_offset = pe_get32 (dll, 0x3c); |
| 220 | opthdr_ofs = pe_header_offset + 4 + 20; |
| 221 | num_entries = pe_get32 (dll, opthdr_ofs + 92); |
| 222 | |
| 223 | if (num_entries < 1) /* No exports. */ |
| 224 | { |
| 225 | return; |
| 226 | } |
| 227 | |
| 228 | export_rva = pe_get32 (dll, opthdr_ofs + 96); |
| 229 | export_size = pe_get32 (dll, opthdr_ofs + 100); |
| 230 | nsections = pe_get16 (dll, pe_header_offset + 4 + 2); |
| 231 | secptr = (pe_header_offset + 4 + 20 + |
| 232 | pe_get16 (dll, pe_header_offset + 4 + 16)); |
| 233 | expptr = 0; |
| 234 | |
| 235 | /* Get the rva and size of the export section. */ |
| 236 | for (i = 0; i < nsections; i++) |
| 237 | { |
| 238 | char sname[8]; |
| 239 | unsigned long secptr1 = secptr + 40 * i; |
| 240 | unsigned long vaddr = pe_get32 (dll, secptr1 + 12); |
| 241 | unsigned long vsize = pe_get32 (dll, secptr1 + 16); |
| 242 | unsigned long fptr = pe_get32 (dll, secptr1 + 20); |
| 243 | |
| 244 | bfd_seek (dll, (file_ptr) secptr1, SEEK_SET0); |
| 245 | bfd_bread (sname, (bfd_size_type) 8, dll); |
| 246 | |
| 247 | if (vaddr <= export_rva && vaddr + vsize > export_rva) |
| 248 | { |
| 249 | expptr = fptr + (export_rva - vaddr); |
| 250 | if (export_rva + export_size > vaddr + vsize) |
| 251 | export_size = vsize - (export_rva - vaddr); |
| 252 | break; |
| 253 | } |
| 254 | } |
| 255 | |
| 256 | if (export_size == 0) |
| 257 | { |
| 258 | /* Empty export table. */ |
| 259 | return; |
| 260 | } |
| 261 | |
| 262 | /* Scan sections and store the base and size of the relevant sections. */ |
| 263 | for (i = 0; i < nsections; i++) |
| 264 | { |
| 265 | unsigned long secptr1 = secptr + 40 * i; |
| 266 | unsigned long vsize = pe_get32 (dll, secptr1 + 8); |
| 267 | unsigned long vaddr = pe_get32 (dll, secptr1 + 12); |
| 268 | unsigned long flags = pe_get32 (dll, secptr1 + 36); |
| 269 | char sec_name[9]; |
| 270 | int sectix; |
| 271 | |
| 272 | sec_name[8] = '\0'; |
| 273 | bfd_seek (dll, (file_ptr) secptr1 + 0, SEEK_SET0); |
| 274 | bfd_bread (sec_name, (bfd_size_type) 8, dll); |
| 275 | |
| 276 | sectix = read_pe_section_index (sec_name); |
| 277 | |
| 278 | if (sectix != PE_SECTION_INDEX_INVALID-1) |
| 279 | { |
| 280 | section_data[sectix].rva_start = vaddr; |
| 281 | section_data[sectix].rva_end = vaddr + vsize; |
| 282 | } |
| 283 | } |
| 284 | |
| 285 | expdata = (unsigned char *) xmalloc (export_size); |
| 286 | back_to = make_cleanup (xfree, expdata); |
| 287 | |
| 288 | bfd_seek (dll, (file_ptr) expptr, SEEK_SET0); |
| 289 | bfd_bread (expdata, (bfd_size_type) export_size, dll); |
| 290 | erva = expdata - export_rva; |
| 291 | |
| 292 | nexp = pe_as32 (expdata + 24); |
| 293 | name_rvas = pe_as32 (expdata + 32); |
| 294 | ordinals = pe_as32 (expdata + 36); |
| 295 | ordbase = pe_as32 (expdata + 16); |
Value stored to 'ordbase' is never read | |
| 296 | exp_funcbase = pe_as32 (expdata + 28); |
| 297 | |
| 298 | /* Use internal dll name instead of full pathname. */ |
| 299 | dll_name = pe_as32 (expdata + 12) + erva; |
| 300 | |
| 301 | bfd_map_over_sections (dll, get_section_vmas, section_data); |
| 302 | |
| 303 | /* Adjust the vma_offsets in case this PE got relocated. This |
| 304 | assumes that *all* sections share the same relocation offset |
| 305 | as the text section. */ |
| 306 | for (i = 0; i < PE_SECTION_TABLE_SIZE3; i++) |
| 307 | { |
| 308 | section_data[i].vma_offset |
| 309 | += ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile))((((objfile->sect_index_text == -1) ? (internal_error ("/usr/src/gnu/usr.bin/binutils/gdb/coff-pe-read.c" , 309, "sect_index_text not initialized"), -1) : objfile-> sect_index_text) == -1) ? (internal_error ("/usr/src/gnu/usr.bin/binutils/gdb/coff-pe-read.c" , 309, "Section index is uninitialized"), -1) : objfile->section_offsets ->offsets[((objfile->sect_index_text == -1) ? (internal_error ("/usr/src/gnu/usr.bin/binutils/gdb/coff-pe-read.c", 309, "sect_index_text not initialized" ), -1) : objfile->sect_index_text)]); |
| 310 | } |
| 311 | |
| 312 | printf_filtered ("Minimal symbols from %s...", dll_name); |
| 313 | wrap_here (""); |
| 314 | |
| 315 | /* Truncate name at first dot. Should maybe also convert to all |
| 316 | lower case for convenience on Windows. */ |
| 317 | read_pe_truncate_name (dll_name); |
| 318 | |
| 319 | /* Iterate through the list of symbols. */ |
| 320 | for (i = 0; i < nexp; i++) |
| 321 | { |
| 322 | /* Pointer to the names vector. */ |
| 323 | unsigned long name_rva = pe_as32 (erva + name_rvas + i * 4); |
| 324 | |
| 325 | /* Pointer to the function address vector. */ |
| 326 | unsigned long func_rva = pe_as32 (erva + exp_funcbase + i * 4); |
| 327 | |
| 328 | /* Find this symbol's section in our own array. */ |
| 329 | int sectix = 0; |
| 330 | |
| 331 | for (sectix = 0; sectix < PE_SECTION_TABLE_SIZE3; ++sectix) |
| 332 | { |
| 333 | if ((func_rva >= section_data[sectix].rva_start) |
| 334 | && (func_rva < section_data[sectix].rva_end)) |
| 335 | { |
| 336 | add_pe_exported_sym (erva + name_rva, |
| 337 | func_rva, |
| 338 | section_data + sectix, dll_name, objfile); |
| 339 | break; |
| 340 | } |
| 341 | } |
| 342 | } |
| 343 | |
| 344 | /* discard expdata. */ |
| 345 | do_cleanups (back_to); |
| 346 | } |