DWARF_GET_VARS(3) BSD Library Functions Manual DWARF_GET_VARS(3)
NAME
dwarf_get_vars, dwarf_var_cu_offset, dwarf_var_die_offset, dwarf_var_name_offsets, dwarf_varname -- retrieve information about static vari-
ables
LIBRARY
DWARF Access Library (libdwarf, -ldwarf)
SYNOPSIS
#include <libdwarf.h>
int
dwarf_get_vars(Dwarf_Debug dbg, Dwarf_Var **vars, Dwarf_Signed *nvars, Dwarf_Error *err);
int
dwarf_var_cu_offset(Dwarf_Var var, Dwarf_Off *cu_offset, Dwarf_Error *err);
int
dwarf_var_die_offset(Dwarf_Var var, Dwarf_Off *die_offset, Dwarf_Error *err);
int
dwarf_var_name_offsets(Dwarf_Var var, char **name, Dwarf_Off *die_offset, Dwarf_Off *cu_die_offset, Dwarf_Error *err);
int
dwarf_varname(Dwarf_Var var, char **name, Dwarf_Error *err);
DESCRIPTION
These functions retrieve information about the file scope static variables associated with a DWARF debug context. Information about these
static variables is returned using opaque descriptors of type Dwarf_Var. Applications need to use the functions described below to retrieve
the name and offset information contained in these descriptors.
Function dwarf_get_vars() retrieves descriptors for all the static variables associated with the DWARF debug context specified by argument
dbg. The argument vars should point to a location that will be set to a pointer to an array of Dwarf_Var descriptors. The argument nvars
should point to a location that will be set to the number of descriptors returned.
Function dwarf_var_cu_offset() returns the section-relative offset, relative to the ``.debug_info'' section, of the compilation unit that
contains the debugging information entry associated with the argument var. Argument cu_offset should point to a location that will hold the
returned offset.
Function dwarf_var_die_offset() retrieves the section-relative offset, relative to the ``.debug_info'' section, of the debugging information
entry associated with the argument var, and stores it into the location pointed to by the argument die_offset.
Function dwarf_var_name_offsets() retrieves both the name and the associated offsets for the debugging information entry for argument var.
Argument name should point to a location which will be set to a pointer to a NUL-terminated string containing the name of the associated
debugging information entry. Argument die_offset should point to a location which will be set to a section-relative offset, relative to the
``.debug_info'' section, of the associated debugging information entry. Argument cu_die_offset should point to a location which will be set
to a section-relative offset, relative to the ``.debug_info'' section, of the first debugging information entry in the compilation unit asso-
ciated with argument var.
Function dwarf_varname() sets the location pointed to by argument name to a pointer to a NUL-terminated string holding the name of the debug-
ging information entry associated with the argument var.
Memory Management
The memory area used for the array of Dwarf_Var descriptors returned in argument vars by function dwarf_get_vars() is owned by the DWARF
Access Library (libdwarf, -ldwarf). Application code should not attempt to directly free this pointer. Portable code should instead use the
function dwarf_vars_dealloc(3) to indicate that the memory area may be freed.
The memory area used for the string returned in the name argument to functions dwarf_var_name_offsets() and dwarf_varname() is owned by the
DWARF Access Library (libdwarf, -ldwarf). Portable code should indicate that the memory area can be freed using the dwarf_dealloc(3) func-
tion.
Error Returns
If argument err is not NULL, these functions will use it to store error information, in case of an error.
RETURN VALUES
On success, these functions returns DW_DLV_OK. In case of an error, they return DW_DLV_ERROR and set the argument err.
ERRORS
These functions may fail with the following errors:
[DW_DLE_ARGUMENT] One of the arguments cu_die_offset, cu_offset, dbg, die_offset, var, vars, name, or nvars was NULL.
SEE ALSO
dwarf(3), dwarf_dealloc(3), dwarf_get_cu_die_offset_given_cu_header_offset(3), dwarf_vars_dealloc(3)
BSD
April 2, 2011 BSD