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DWARF_GET_ABBREV(3)        Library Functions Manual        DWARF_GET_ABBREV(3)

     dwarf_get_abbrev - retrieve abbreviation information

     DWARF Access Library (libdwarf, -ldwarf)

     #include <libdwarf.h>

     dwarf_get_abbrev(Dwarf_Debug dbg, Dwarf_Unsigned offset,
         Dwarf_Abbrev *ret_abbrev, Dwarf_Unsigned *length,
         Dwarf_Unsigned *attr_count, Dwarf_Error *err);

     Function dwarf_get_abbrev() retrieves information about an abbreviation
     from the DWARF abbreviations section, ".debug_abbrev".  Abbreviation
     information is returned using an opaque descriptor of type Dwarf_Abbrev.
     The returned Dwarf_Abbrev descriptor may then be passed to the other
     abbreviation related APIs in the DWARF(3) API to retrieve specific
     information about the abbreviation.

     Argument dbg should reference a DWARF debug context allocated using

     Argument offset should be an offset, relative to the ".debug_abbrev"
     section, to the start of an abbreviation entry.

     Argument ret_abbrev should point to a location that will hold a pointer
     to the returned Dwarf_Abbrev descriptor.

     Argument length should point to a location that will hold the number of
     bytes used by the abbrevation in the DWARF ".debug_abbrev" section.

     Argument attr_count should point to a location that will hold the number
     of attributes in the abbrevation.

     If argument err is not NULL, it will be used to store error information
     in case of an error.

   Memory Management
     The memory area used for the Dwarf_Abbrev descriptor returned in argument
     ret_abbrev is allocated by the DWARF Access Library (libdwarf, -ldwarf).
     Application code should use function dwarf_dealloc() with the allocation
     type DW_DLA_ABBREV to free the memory area when the Dwarf_Abbrev
     descriptor is no longer needed.

   Application Programming Notes
     The last abbreviation entry in a standard DWARF abbreviation section will
     have a special length value of 1.

     Function dwarf_get_abbrev() returns DW_DLV_OK when it succeeds.  It
     returns DW_DLV_NO_ENTRY if there is no abbreviation information at offset
     offset.  In case of an error, it returns DW_DLV_ERROR and sets the
     argument err.

     To loop through all the abbreviation information associated with a DWARF
     debug context, use:

           Dwarf_Debug dbg;
           Dwarf_Abbrev ab;
           Dwarf_Off aboff;
           Dwarf_Unsigned length, attr_count;
           Dwarf_Half tag;
           Dwarf_Error de;
           int ret;

           while ((ret = dwarf_next_cu_header(dbg, NULL, NULL, &aboff,
               NULL, NULL, &de)) ==  DW_DLV_OK) {
                   while ((ret = dwarf_get_abbrev(re->dbg, aboff, &ab, &length,
                       &attr_count, &de)) == DW_DLV_OK) {
                           if (length == 1)        /* Last entry. */
                           aboff += length;
                           if (dwarf_get_abbrev_tag(ab, &tag, &de) != DW_DLV_OK) {
                                   warnx("dwarf_get_abbrev_tag failed: %s",
                   if (ret != DW_DLV_OK)
                           warnx("dwarf_get_abbrev: %s", dwarf_errmsg(de));
           if (ret == DW_DLV_ERROR)
                   warnx("dwarf_next_cu_header: %s", dwarf_errmsg(de));

     Function dwarf_get_abbrev() can fail with:

     [DW_DLE_ARGUMENT]       One of the arguments dbg, ret_abbrev, length or
                             attr_count was NULL.

     [DW_DLE_NO_ENTRY]       There is no abbreviation information at offset

     dwarf(3), dwarf_dealloc(3), dwarf_get_abbrev_children_flag(3),
     dwarf_get_abbrev_code(3), dwarf_get_abbrev_entry(3),

NetBSD 10.99                    March 27, 2011                    NetBSD 10.99