libdwarf
Examining Section Group data

Example accessing Section Group data.

With split dwarf your libdwarf calls after than the initial open are done against the base Dwarf_Dbg and libdwarf automatically looks in the open tied dbg when and as appropriate. the tied-dbg can be detached too, see example3 link, though you must call dwarf_finish() on the detached dw_tied_dbg, the library will not do that for you..

Section groups apply to Elf COMDAT groups too.

*/
void examplesecgroup(Dwarf_Debug dbg)
{
int res = 0;
Dwarf_Unsigned section_count = 0;
Dwarf_Unsigned group_count;
Dwarf_Unsigned selected_group = 0;
Dwarf_Unsigned group_map_entry_count = 0;
Dwarf_Unsigned *sec_nums = 0;
Dwarf_Unsigned *group_nums = 0;
const char ** sec_names = 0;
Dwarf_Error error = 0;
res = dwarf_sec_group_sizes(dbg,&section_count,
&group_count,&selected_group, &group_map_entry_count,
&error);
if (res != DW_DLV_OK) {
/* Something is badly wrong*/
return;
}
/* In an object without split-dwarf sections
or COMDAT sections we now have
selected_group == 1. */
sec_nums = calloc(group_map_entry_count,sizeof(Dwarf_Unsigned));
if (!sec_nums) {
/* FAIL. out of memory */
return;
}
group_nums = calloc(group_map_entry_count,sizeof(Dwarf_Unsigned));
if (!group_nums) {
free(group_nums);
/* FAIL. out of memory */
return;
}
sec_names = calloc(group_map_entry_count,sizeof(char*));
if (!sec_names) {
free(group_nums);
free(sec_nums);
/* FAIL. out of memory */
return;
}
res = dwarf_sec_group_map(dbg,group_map_entry_count,
group_nums,sec_nums,sec_names,&error);
if (res != DW_DLV_OK) {
/* FAIL. Something badly wrong. */
free(sec_names);
free(group_nums);
free(sec_nums);
}
for ( i = 0; i < group_map_entry_count; ++i) {
/* Now do something with
group_nums[i],sec_nums[i],sec_names[i] */
}
/* The strings are in Elf data.
Do not free() the strings themselves.*/
free(sec_names);
free(group_nums);
free(sec_nums);
}
struct Dwarf_Debug_s * Dwarf_Debug
Definition: libdwarf.h:586
struct Dwarf_Error_s * Dwarf_Error
Definition: libdwarf.h:580
unsigned long long Dwarf_Unsigned
Definition: libdwarf.h:196
int dwarf_sec_group_sizes(Dwarf_Debug dw_dbg, Dwarf_Unsigned *dw_section_count_out, Dwarf_Unsigned *dw_group_count_out, Dwarf_Unsigned *dw_selected_group_out, Dwarf_Unsigned *dw_map_entry_count_out, Dwarf_Error *dw_error)
Get Section Groups data counts.
int dwarf_sec_group_map(Dwarf_Debug dw_dbg, Dwarf_Unsigned dw_map_entry_count, Dwarf_Unsigned *dw_group_numbers_array, Dwarf_Unsigned *dw_sec_numbers_array, const char **dw_sec_names_array, Dwarf_Error *dw_error)
Return a map between group numbers and section numbers.