dwarf_get_str(3) [freebsd man page]

DWARF_GET_STR(3)					   BSD Library Functions Manual 					  DWARF_GET_STR(3)

NAME

     dwarf_get_str -- retrieve a string from the DWARF string section

LIBRARY

     DWARF Access Library (libdwarf, -ldwarf)

SYNOPSIS

     #include <libdwarf.h>

     int
     dwarf_get_str(Dwarf_Debug dbg, Dwarf_Off offset, char **string, Dwarf_Signed *len, Dwarf_Error *err);

DESCRIPTION

     Function dwarf_get_str() retrieves a NUL-terminated string from the DWARF string section ``.debug_str''.

     Argument dbg should reference a DWARF debug context allocated using dwarf_init(3).

     Argument offset should be an offset, relative to the ``.debug_str'' section, specifying the start of the desired string.

     Argument string should point to a location which will hold a returned pointer to a NUL-terminated string.

     Argument len should point to a location which will hold the length of the returned string.  The returned length does not include the space
     needed for the NUL-terminator.

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

RETURN VALUES

     Function dwarf_get_str() returns DW_DLV_OK when it succeeds.  It returns DW_DLV_NO_ENTRY if there is no ``.debug_str'' section associated
     with the specified debugging context, or if the provided offset offset is at the very end of ``.debug_str'' section.  In case of an error, it
     returns DW_DLV_ERROR and sets the argument err.

ERRORS

     Function dwarf_get_str() can fail with:

     [DW_DLE_ARGUMENT]	One of the arguments dbg, string or len was NULL.

     [DW_DLE_ARGUMENT]	Argument offset was out of range.

     [DW_DLE_NO_ENTRY]	The debugging context dbg did not contain a ``.debug_str'' string section.

     [DW_DLE_NO_ENTRY]	Argument offset was at the very end of the ``.debug_str'' section.

EXAMPLE

     To retrieve all the strings in the DWARF string section, use:

	   Dwarf_Debug dbg;
	   Dwarf_Off offset;
	   Dwarf_Signed len;
	   Dwarf_Error de;
	   char *str;
	   int ret

	   offset = 0;
	   while ((ret = dwarf_get_str(dbg, offset, &str, &len, &de)) ==
		   DW_DLV_OK) {
		   /* .. Use the retrieved string. .. */
		   offset += len + 1; /* Account for the terminating NUL. */
	   }

	   if (ret == DW_DLV_ERROR)
		   warnx("dwarf_get_str: %s", dwarf_errmsg(de));

SEE ALSO

     dwarf(3), dwarf_init(3)

BSD
								   April 3, 2011							       BSD

DWARF_GET_ABBREV_ENTRY(3)				   BSD Library Functions Manual 				 DWARF_GET_ABBREV_ENTRY(3)

NAME

     dwarf_get_abbrev_entry -- retrieve attribute information from an abbreviation descriptor

LIBRARY

     DWARF Access Library (libdwarf, -ldwarf)

SYNOPSIS

     #include <libdwarf.h>

     int
     dwarf_get_abbrev_entry(Dwarf_Abbrev abbrev, Dwarf_Signed ndx, Dwarf_Half *code, Dwarf_Signed *form, Dwarf_Off *offset, Dwarf_Error *err);

DESCRIPTION

     Function dwarf_get_abbrev_entry() retrieves attribute information from a DWARF abbreviation descriptor.

     Argument abbrev should be a valid abbreviation descriptor, as returned by function dwarf_get_abbrev(3).

     Argument ndx specifies the 0-based index of the attribute.  The total count of the attributes contained in the abbreviation entry can be
     retrieved using the function dwarf_get_abbrev(3).

     Argument code should point to a location which will hold a returned attribute code.

     Argument form should point to a location which will hold the returned form of the attribute.

     Argument offset should point to a location which will hold a returned offset, relative to the ``.debug_abbrev'' section, for the specified
     attribute.

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

RETURN VALUES

     Function dwarf_get_abbrev_entry() returns DW_DLV_OK when it succeeds.  It returns DW_DLV_NO_ENTRY if the attribute index specified by argu-
     ment ndx is out of range.	In case of an error, it returns DW_DLV_ERROR and sets the argument err.

ERRORS

     Function dwarf_get_abbrev_entry() can fail with:

     [DW_DLE_ARGUMENT]	One of the arguments abbrev, code, form or offset was NULL.

     [DW_DLE_NO_ENTRY]	The attribute index specified by argument ndx was out of range.

EXAMPLE

     To loop through all the attribute entries contained in the abbreviation section, use:

	   Dwarf_Debug dbg;
	   Dwarf_Abbrev ab;
	   Dwarf_Off aboff, atoff;
	   Dwarf_Signed form;
	   Dwarf_Half attr;
	   Dwarf_Unsigned length, attr_count;
	   Dwarf_Error de;
	   int i, ret;

	   /* ...allocate 'dbg' using dwarf_init(3) ... */

	   while ((ret = dwarf_next_cu_header(dbg, NULL, NULL, &aboff,
	       NULL, NULL, &de)) ==  DW_DLV_OK) {
		   while ((ret = dwarf_get_abbrev(dbg, aboff, &ab, &length,
		       &attr_count, &de)) == DW_DLV_OK) {
			   if (length == 1)	   /* Last entry. */
				   break;
			   aboff += length;
			   for (i = 0; (Dwarf_Unsigned) i < attr_count; i++) {
				   if (dwarf_get_abbrev_entry(ab, i,
				       &attr, &form, &atoff, &de) != DW_DLV_OK) {
					   warnx("dwarf_get_abbrev_entry failed:"
					       " %s", dwarf_errmsg(de));
					   continue;
				   }
				   /* .. use the retrieved information ... */
			   }
		   }

		   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));

SEE ALSO

     dwarf(3), dwarf_get_abbrev(3)

BSD
								  April 02, 2011							       BSD