[PATCH 3/3] dbghelp: use elf load_offset passed to dwarf2_parse to relocate addresses

[Peter Oberndorfer]

this is needed, because symbol addresses in dwarf2 debug info are already relocated
---
if the module base of the real image is different than the module base of the debug link file
the symbols are in the wrong location else

This allows me to get debugging information for kernel32.dll.so/ntdll.dll.so after i installed prelink

 dlls/dbghelp/dwarf.c |   23 +++++++++++++----------
 1 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/dlls/dbghelp/dwarf.c b/dlls/dbghelp/dwarf.c
index 3f2f5c7..1219522 100644
--- a/dlls/dbghelp/dwarf.c
+++ b/dlls/dbghelp/dwarf.c
@@ -178,6 +178,7 @@ typedef struct dwarf2_parse_context_s
     const struct elf_thunk_area*thunks;
     struct sparse_array         abbrev_table;
     struct sparse_array         debug_info_table;
+    unsigned long               load_offset;
     unsigned long               ref_offset;
     unsigned char               word_size;
 } dwarf2_parse_context_t;
@@ -1301,7 +1302,7 @@ static void dwarf2_parse_variable(dwarf2_subprogram_t* subpgm,
                 ext.u.uvalue = 0;
             symt_new_global_variable(subpgm->ctx->module, subpgm->compiland,
                                      name.u.string, !ext.u.uvalue,
-                                     subpgm->ctx->module->module.BaseOfImage + loc.offset,
+                                     subpgm->ctx->load_offset + loc.offset,
                                      0, param_type);
             break;
         default:
@@ -1384,7 +1385,7 @@ static void dwarf2_parse_subprogram_label(dwarf2_subprogram_t* subpgm,
         name.u.string = NULL;
 
     loc.kind = loc_absolute;
-    loc.offset = subpgm->ctx->module->module.BaseOfImage + low_pc.u.uvalue,
+    loc.offset = subpgm->ctx->load_offset + low_pc.u.uvalue;
     symt_add_function_point(subpgm->ctx->module, subpgm->func, SymTagLabel,
                             &loc, name.u.string);
 }
@@ -1407,7 +1408,7 @@ static void dwarf2_parse_inlined_subroutine(dwarf2_subprogram_t* subpgm,
     if (!dwarf2_find_attribute(subpgm->ctx, di, DW_AT_high_pc, &high_pc)) high_pc.u.uvalue = 0;
 
     block = symt_open_func_block(subpgm->ctx->module, subpgm->func, parent_block,
-                                 subpgm->ctx->module->module.BaseOfImage + low_pc.u.uvalue - subpgm->func->address,
+                                 subpgm->ctx->load_offset + low_pc.u.uvalue - subpgm->func->address,
                                  high_pc.u.uvalue - low_pc.u.uvalue);
 
     if (di->abbrev->have_child) /** any interest to not have child ? */
@@ -1460,7 +1461,7 @@ static void dwarf2_parse_subprogram_block(dwarf2_subprogram_t* subpgm,
         high_pc.u.uvalue = 0;
 
     block = symt_open_func_block(subpgm->ctx->module, subpgm->func, parent_block,
-                                 subpgm->ctx->module->module.BaseOfImage + low_pc.u.uvalue - subpgm->func->address,
+                                 subpgm->ctx->load_offset + low_pc.u.uvalue - subpgm->func->address,
                                  high_pc.u.uvalue - low_pc.u.uvalue);
 
     if (di->abbrev->have_child) /** any interest to not have child ? */
@@ -1547,7 +1548,7 @@ static struct symt* dwarf2_parse_subprogram(dwarf2_parse_context_t* ctx,
      * (not the case for stabs), we just drop Wine's thunks here...
      * Actual thunks will be created in elf_module from the symbol table
      */
-    if (elf_is_in_thunk_area(ctx->module->module.BaseOfImage + low_pc.u.uvalue,
+    if (elf_is_in_thunk_area(ctx->load_offset + low_pc.u.uvalue,
                              ctx->thunks) >= 0)
         return NULL;
     if (!dwarf2_find_attribute(ctx, di, DW_AT_declaration, &is_decl))
@@ -1561,7 +1562,7 @@ static struct symt* dwarf2_parse_subprogram(dwarf2_parse_context_t* ctx,
     if (!is_decl.u.uvalue)
     {
         subpgm.func = symt_new_function(ctx->module, compiland, name.u.string,
-                                        ctx->module->module.BaseOfImage + low_pc.u.uvalue,
+                                        ctx->load_offset + low_pc.u.uvalue,
                                         high_pc.u.uvalue - low_pc.u.uvalue,
                                         &sig_type->symt);
         di->symt = &subpgm.func->symt;
@@ -1908,7 +1909,7 @@ static BOOL dwarf2_parse_line_numbers(const dwarf2_section_t* sections,
                         end_sequence = TRUE;
                         break;
                     case DW_LNE_set_address:
-                        address = ctx->module->module.BaseOfImage + dwarf2_parse_addr(&traverse);
+                        address = ctx->load_offset + dwarf2_parse_addr(&traverse);
                         break;
                     case DW_LNE_define_file:
                         FIXME("not handled %s\n", traverse.data);
@@ -1938,7 +1939,8 @@ static BOOL dwarf2_parse_compilation_unit(const dwarf2_section_t* sections,
                                           const dwarf2_comp_unit_t* comp_unit,
                                           struct module* module,
                                           const struct elf_thunk_area* thunks,
-                                          const unsigned char* comp_unit_cursor)
+                                          const unsigned char* comp_unit_cursor,
+                                          unsigned long load_offset)
 {
     dwarf2_parse_context_t ctx;
     dwarf2_traverse_context_t traverse;
@@ -1966,6 +1968,7 @@ static BOOL dwarf2_parse_compilation_unit(const dwarf2_section_t* sections,
     ctx.module = module;
     ctx.word_size = comp_unit->word_size;
     ctx.thunks = thunks;
+    ctx.load_offset = load_offset;
     ctx.ref_offset = comp_unit_cursor - sections[section_debug].address;
 
     traverse.start_data = comp_unit_cursor + sizeof(dwarf2_comp_unit_stream_t);
@@ -1999,7 +2002,7 @@ static BOOL dwarf2_parse_compilation_unit(const dwarf2_section_t* sections,
         if (!dwarf2_find_attribute(&ctx, di, DW_AT_low_pc, &low_pc))
             low_pc.u.uvalue = 0;
         di->symt = &symt_new_compiland(module, 
-                                       module->module.BaseOfImage + low_pc.u.uvalue,
+                                       ctx.load_offset + low_pc.u.uvalue,
                                        source_new(module, comp_dir.u.string, name.u.string))->symt;
 
         if (di->abbrev->have_child)
@@ -2208,7 +2211,7 @@ BOOL dwarf2_parse(struct module* module, unsigned long load_offset,
         comp_unit.word_size = *(unsigned char*) comp_unit_stream->word_size;
 
         dwarf2_parse_compilation_unit(section, &comp_unit, module,
-                                      thunks, comp_unit_cursor);
+                                      thunks, comp_unit_cursor, load_offset);
         comp_unit_cursor += comp_unit.length + sizeof(unsigned);
     }
     module->module.SymType = SymDia;
-- 
1.5.0.3