--- /dev/null
+/* Read the export table symbols from a portable executable and
+ convert to internal format, for GDB. Used as a last resort if no
+ debugging symbols recognized.
+
+ Copyright 2003 Free Software Foundation, Inc.
+
+ This file is part of GDB.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+
+ Contributed by Raoul M. Gough (RaoulGough@yahoo.co.uk). */
+
+#include "coff-pe-read.h"
+
+#include "bfd.h"
+
+#include "defs.h"
+#include "gdbtypes.h"
+
+#include "symtab.h"
+#include "symfile.h"
+#include "objfiles.h"
+
+/* Internal section information */
+
+struct read_pe_section_data
+{
+ CORE_ADDR vma_offset; /* Offset to loaded address of section. */
+ unsigned long rva_start; /* Start offset within the pe. */
+ unsigned long rva_end; /* End offset within the pe. */
+ enum minimal_symbol_type ms_type; /* Type to assign symbols in section. */
+};
+
+#define PE_SECTION_INDEX_TEXT 0
+#define PE_SECTION_INDEX_DATA 1
+#define PE_SECTION_INDEX_BSS 2
+#define PE_SECTION_TABLE_SIZE 3
+#define PE_SECTION_INDEX_INVALID -1
+\f
+/* Get the index of the named section in our own array, which contains
+ text, data and bss in that order. Return PE_SECTION_INDEX_INVALID
+ if passed an unrecognised section name. */
+
+static int
+read_pe_section_index (const char *section_name)
+{
+ if (strcmp (section_name, ".text") == 0)
+ {
+ return PE_SECTION_INDEX_TEXT;
+ }
+
+ else if (strcmp (section_name, ".data") == 0)
+ {
+ return PE_SECTION_INDEX_DATA;
+ }
+
+ else if (strcmp (section_name, ".bss") == 0)
+ {
+ return PE_SECTION_INDEX_BSS;
+ }
+
+ else
+ {
+ return PE_SECTION_INDEX_INVALID;
+ }
+}
+
+/* Record the virtual memory address of a section. */
+
+static void
+get_section_vmas (bfd *abfd, asection *sectp, void *context)
+{
+ struct read_pe_section_data *sections = context;
+ int sectix = read_pe_section_index (sectp->name);
+
+ if (sectix != PE_SECTION_INDEX_INVALID)
+ {
+ /* Data within the section start at rva_start in the pe and at
+ bfd_get_section_vma() within memory. Store the offset. */
+
+ sections[sectix].vma_offset
+ = bfd_get_section_vma (abfd, sectp) - sections[sectix].rva_start;
+ }
+}
+\f
+/* Create a minimal symbol entry for an exported symbol. */
+
+static void
+add_pe_exported_sym (char *sym_name,
+ unsigned long func_rva,
+ const struct read_pe_section_data *section_data,
+ const char *dll_name, struct objfile *objfile)
+{
+ /* Add the stored offset to get the loaded address of the symbol. */
+
+ CORE_ADDR vma = func_rva + section_data->vma_offset;
+
+ char *qualified_name = 0;
+ int dll_name_len = strlen (dll_name);
+ int count;
+
+ /* Generate a (hopefully unique) qualified name using the first part
+ of the dll name, e.g. KERNEL32!AddAtomA. This matches the style
+ used by windbg from the "Microsoft Debugging Tools for Windows". */
+
+ qualified_name = xmalloc (dll_name_len + strlen (sym_name) + 2);
+
+ strncpy (qualified_name, dll_name, dll_name_len);
+ qualified_name[dll_name_len] = '!';
+ strcpy (qualified_name + dll_name_len + 1, sym_name);
+
+ prim_record_minimal_symbol (qualified_name,
+ vma, section_data->ms_type, objfile);
+
+ xfree (qualified_name);
+
+ /* Enter the plain name as well, which might not be unique. */
+ prim_record_minimal_symbol (sym_name, vma, section_data->ms_type, objfile);
+}
+
+/* Truncate a dll_name at the first dot character. */
+
+static void
+read_pe_truncate_name (char *dll_name)
+{
+ while (*dll_name)
+ {
+ if ((*dll_name) == '.')
+ {
+ *dll_name = '\0'; /* truncates and causes loop exit. */
+ }
+
+ else
+ {
+ ++dll_name;
+ }
+ }
+}
+\f
+/* Low-level support functions, direct from the ld module pe-dll.c. */
+static unsigned int
+pe_get16 (bfd *abfd, int where)
+{
+ unsigned char b[2];
+
+ bfd_seek (abfd, (file_ptr) where, SEEK_SET);
+ bfd_bread (b, (bfd_size_type) 2, abfd);
+ return b[0] + (b[1] << 8);
+}
+
+static unsigned int
+pe_get32 (bfd *abfd, int where)
+{
+ unsigned char b[4];
+
+ bfd_seek (abfd, (file_ptr) where, SEEK_SET);
+ bfd_bread (b, (bfd_size_type) 4, abfd);
+ return b[0] + (b[1] << 8) + (b[2] << 16) + (b[3] << 24);
+}
+
+static unsigned int
+pe_as32 (void *ptr)
+{
+ unsigned char *b = ptr;
+
+ return b[0] + (b[1] << 8) + (b[2] << 16) + (b[3] << 24);
+}
+\f
+/* Read the (non-debug) export symbol table from a portable
+ executable. Code originally lifted from the ld function
+ pe_implied_import_dll in pe-dll.c. */
+
+void
+read_pe_exported_syms (struct objfile *objfile)
+{
+ bfd *dll = objfile->obfd;
+ unsigned long pe_header_offset, opthdr_ofs, num_entries, i;
+ unsigned long export_rva, export_size, nsections, secptr, expptr;
+ unsigned long exp_funcbase;
+ unsigned char *expdata, *erva;
+ unsigned long name_rvas, ordinals, nexp, ordbase;
+ char *dll_name;
+
+ /* Array elements are for text, data and bss in that order
+ Initialization with start_rva > end_rva guarantees that
+ unused sections won't be matched. */
+ struct read_pe_section_data section_data[PE_SECTION_TABLE_SIZE]
+ = { {0, 1, 0, mst_text},
+ {0, 1, 0, mst_data},
+ {0, 1, 0, mst_bss}
+ };
+
+ struct cleanup *back_to = 0;
+
+ char const *target = bfd_get_target (objfile->obfd);
+
+ if ((strcmp (target, "pe-i386") != 0) && (strcmp (target, "pei-i386") != 0))
+ {
+ /* This is not an i386 format file. Abort now, because the code
+ is untested on anything else. *FIXME* test on further
+ architectures and loosen or remove this test. */
+ return;
+ }
+
+ /* Get pe_header, optional header and numbers of export entries. */
+ pe_header_offset = pe_get32 (dll, 0x3c);
+ opthdr_ofs = pe_header_offset + 4 + 20;
+ num_entries = pe_get32 (dll, opthdr_ofs + 92);
+
+ if (num_entries < 1) /* No exports. */
+ {
+ return;
+ }
+
+ export_rva = pe_get32 (dll, opthdr_ofs + 96);
+ export_size = pe_get32 (dll, opthdr_ofs + 100);
+ nsections = pe_get16 (dll, pe_header_offset + 4 + 2);
+ secptr = (pe_header_offset + 4 + 20 +
+ pe_get16 (dll, pe_header_offset + 4 + 16));
+ expptr = 0;
+
+ /* Get the rva and size of the export section. */
+ for (i = 0; i < nsections; i++)
+ {
+ char sname[8];
+ unsigned long secptr1 = secptr + 40 * i;
+ unsigned long vaddr = pe_get32 (dll, secptr1 + 12);
+ unsigned long vsize = pe_get32 (dll, secptr1 + 16);
+ unsigned long fptr = pe_get32 (dll, secptr1 + 20);
+
+ bfd_seek (dll, (file_ptr) secptr1, SEEK_SET);
+ bfd_bread (sname, (bfd_size_type) 8, dll);
+
+ if (vaddr <= export_rva && vaddr + vsize > export_rva)
+ {
+ expptr = fptr + (export_rva - vaddr);
+ if (export_rva + export_size > vaddr + vsize)
+ export_size = vsize - (export_rva - vaddr);
+ break;
+ }
+ }
+
+ if (export_size == 0)
+ {
+ /* Empty export table. */
+ return;
+ }
+
+ /* Scan sections and store the base and size of the relevant sections. */
+ for (i = 0; i < nsections; i++)
+ {
+ unsigned long secptr1 = secptr + 40 * i;
+ unsigned long vsize = pe_get32 (dll, secptr1 + 8);
+ unsigned long vaddr = pe_get32 (dll, secptr1 + 12);
+ unsigned long flags = pe_get32 (dll, secptr1 + 36);
+ char sec_name[9];
+ int sectix;
+
+ sec_name[8] = '\0';
+ bfd_seek (dll, (file_ptr) secptr1 + 0, SEEK_SET);
+ bfd_bread (sec_name, (bfd_size_type) 8, dll);
+
+ sectix = read_pe_section_index (sec_name);
+
+ if (sectix != PE_SECTION_INDEX_INVALID)
+ {
+ section_data[sectix].rva_start = vaddr;
+ section_data[sectix].rva_end = vaddr + vsize;
+ }
+ }
+
+ expdata = (unsigned char *) xmalloc (export_size);
+ back_to = make_cleanup (xfree, expdata);
+
+ bfd_seek (dll, (file_ptr) expptr, SEEK_SET);
+ bfd_bread (expdata, (bfd_size_type) export_size, dll);
+ erva = expdata - export_rva;
+
+ nexp = pe_as32 (expdata + 24);
+ name_rvas = pe_as32 (expdata + 32);
+ ordinals = pe_as32 (expdata + 36);
+ ordbase = pe_as32 (expdata + 16);
+ exp_funcbase = pe_as32 (expdata + 28);
+
+ /* Use internal dll name instead of full pathname. */
+ dll_name = pe_as32 (expdata + 12) + erva;
+
+ bfd_map_over_sections (dll, get_section_vmas, section_data);
+
+ /* Adjust the vma_offsets in case this PE got relocated. This
+ assumes that *all* sections share the same relocation offset
+ as the text section. */
+ for (i = 0; i < PE_SECTION_TABLE_SIZE; i++)
+ {
+ section_data[i].vma_offset
+ += ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));
+ }
+
+ printf_filtered ("Minimal symbols from %s...", dll_name);
+ wrap_here ("");
+
+ /* Truncate name at first dot. Should maybe also convert to all
+ lower case for convenience on Windows. */
+ read_pe_truncate_name (dll_name);
+
+ /* Iterate through the list of symbols. */
+ for (i = 0; i < nexp; i++)
+ {
+ /* Pointer to the names vector. */
+ unsigned long name_rva = pe_as32 (erva + name_rvas + i * 4);
+
+ /* Pointer to the function address vector. */
+ unsigned long func_rva = pe_as32 (erva + exp_funcbase + i * 4);
+
+ /* Find this symbol's section in our own array. */
+ int sectix = 0;
+
+ for (sectix = 0; sectix < PE_SECTION_TABLE_SIZE; ++sectix)
+ {
+ if ((func_rva >= section_data[sectix].rva_start)
+ && (func_rva < section_data[sectix].rva_end))
+ {
+ add_pe_exported_sym (erva + name_rva,
+ func_rva,
+ section_data + sectix, dll_name, objfile);
+ break;
+ }
+ }
+ }
+
+ /* discard expdata. */
+ do_cleanups (back_to);
+}
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