dwarf_def_macro(3) [freebsd man page]

DWARF_DEF_MACRO(3)					   BSD Library Functions Manual 					DWARF_DEF_MACRO(3)

NAME

     dwarf_def_macro -- add a macro definition to a DWARF producer instance

LIBRARY

     DWARF Access Library (libdwarf, -ldwarf)

SYNOPSIS

     #include <libdwarf.h>

     int
     dwarf_def_macro(Dwarf_P_Debug dbg, Dwarf_Unsigned lineno, char *name, char *value, Dwarf_Error *err);

DESCRIPTION

     Function dwarf_def_macro() adds a macro definition to a DWARF producer instance.

     Argument dbg should reference a DWARF producer instance allocated using dwarf_producer_init(3) or dwarf_producer_init_b(3).

     Argument lineno specifies the line number of the source line where the macro is defined.  A line number of zero is used for macros that are
     defined before any source file is read.

     Argument name should point to a NUL-terminated string containing the name of the macro.  For function-like macros this parameter should also
     include parentheses and parameter names if any.

     Argument value should point to a NUL-terminated string containing the value of the macro.	If the macro doesn't have a value, argument value
     should be set to NULL.

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

RETURN VALUES

     On success, function dwarf_def_macro() returns DW_DLV_OK.	In case of an error, function dwarf_def_macro() returns DW_DLV_ERROR and sets the
     argument err.

EXAMPLE

     To record the fact that a macro named _STDIO_H_ was defined at line 20 of the current macro file, use:

	   Dwarf_P_Debug dbg;
	   Dwarf_Error de;

	   /* ... Assume 'dbg' refers to a DWARF producer instance... */
	   if (dwarf_def_macro(dbg, 20, "_STDIO_H_", NULL, &de) != DW_DLV_OK)
		   errx(EXIT_FAILURE, "dwarf_def_macro failed: %s",
		       dwarf_errmsg(-1));

ERRORS

     Function dwarf_def_macro() can fail with:

     [DW_DLE_ARGUMENT]	Either arguments dbg or name was NULL.

     [DW_DLE_MEMORY]	An out of memory condition was encountered during the execution of the function.

SEE ALSO

     dwarf(3), dwarf_end_macro_file(3), dwarf_producer_init(3), dwarf_producer_init_b(3), dwarf_start_macro_file(3), dwarf_undef_macro(3),
     dwarf_vendor_ext(3)

BSD
								 November 9, 2011							       BSD

DWARF_NEW_EXPR(3)					   BSD Library Functions Manual 					 DWARF_NEW_EXPR(3)

NAME

     dwarf_new_expr -- create a location expression descriptor

LIBRARY

     DWARF Access Library (libdwarf, -ldwarf)

SYNOPSIS

     #include <libdwarf.h>

     Dwarf_P_Expr
     dwarf_new_expr(Dwarf_P_Debug dbg, Dwarf_Error *err);

DESCRIPTION

     Function dwarf_new_expr() allocates a DWARF location expression descriptor used to build up a location expression stream.

     The application can use the functions dwarf_add_expr_gen(3) and dwarf_add_expr_addr_b(3) to add location expression operators to the created
     descriptor.  When done, the application can call the function dwarf_expr_into_block(3) to retrieve the generated byte stream for the location
     expression, or call the function dwarf_add_AT_location_expr(3) to create an attribute with the location expression stream as its value.

     Argument dbg should reference a DWARF producer instance allocated using dwarf_producer_init(3) or dwarf_producer_init_b(3).

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

RETURN VALUES

     On success, function dwarf_new_expr() returns the created location expression descriptor.	In case of an error, function dwarf_new_expr()
     returns DW_DLV_BADADDR and sets the argument err.

ERRORS

     Function dwarf_new_expr() can fail with:

     [DW_DLE_ARGUMENT]	Argument dbg was NULL.

     [DW_DLE_MEMORY]	An out of memory condition was encountered during the execution of the function.

EXAMPLES

     To create a location expression descriptor, add location expression operators to it and to retrieve the generated byte stream, use:

	   Dwarf_P_Debug dbg;
	   Dwarf_Error de;
	   Dwarf_P_Expr pe;
	   Dwarf_Addr buf;
	   Dwarf_Unsigned len;

	   /* ...Assume that `dbg' refers to a DWARF producer instance... */

	   if ((pe = dwarf_new_expr(dbg, &de)) == DW_DLV_BADADDR) {
		   warnx("dwarf_new_expr failed: %s", dwarf_errmsg(-1));
		   return;
	   }

	   if (dwarf_add_expr_gen(pe, DW_OP_regx, 55, 0, &de) ==
	       DW_DLV_NOCOUNT) {
		   warnx("dwarf_add_expr_gen failed: %s", dwarf_errmsg(-1));
		   return;
	   }

	   if ((buf = dwarf_expr_into_block(pe, &len, &de)) ==
	       DW_DLV_BADADDR) {
		   warnx("dwarf_expr_into_block failed: %s",
		       dwarf_errmsg(-1));
		   return;
	   }

SEE ALSO

     dwarf(3), dwarf_add_AT_location_expr(3), dwarf_add_expr_gen(3), dwarf_add_expr_addr(3), dwarf_add_expr_addr_b(3),
     dwarf_expr_current_offset(3), dwarf_expr_into_block(3), dwarf_producer_init(3), dwarf_producer_init_b(3)

BSD
								 September 8, 2011							       BSD