NAME

dwarf_add_line_entry — add a line number information entry to a producer instance

LIBRARY

DWARF Access Library (libdwarf, -ldwarf)

SYNOPSIS

#include <libdwarf.h>

Dwarf_Unsigned
dwarf_add_line_entry(Dwarf_P_Debug dbg, Dwarf_Unsigned filendx, Dwarf_Addr off, Dwarf_Unsigned lineno, Dwarf_Signed column, Dwarf_Bool is_stmt, Dwarf_Bool basic_block, Dwarf_Error *err);

DESCRIPTION

Function dwarf_add_line_entry() adds a line number information entry 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 filendx specifies the index of the source file that contains the source line in question. Valid source file indices are those returned by the function dwarf_add_file_decl(3).

Argument off specifies a relocatable program address. The ELF symbol to be used for relocation is set by a prior call to the function dwarf_lne_set_address(3).

Argument lineno specifies the line number of the source line.

Argument column specifies the column number within the source line.

If the argument is_stmt is set to true, it indicates that the instruction at the address specified by argument off is a recommended breakpoint location, i.e., the first instruction in the instruction sequence generated by the source line.

If the argument basic_block is set to true, it indicates that the instruction at the address specified by argument off is the first instruction of a basic block.

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_add_line_entry() returns DW_DLV_OK. In case of an error, function dwarf_add_line_entry() returns DW_DLV_NOCOUNT and sets the argument err.

EXAMPLES

To add line number information to the producer instance, use:

Dwarf_P_Debug dbg;
Dwarf_Error de;
Dwarf_Unsigned dir, filendx;

/* ... assume dbg refers to a DWARF producer instance ... */

dir = dwarf_add_directory_decl(dbg, "/home/foo", &de);
if (dir == DW_DLV_NOCOUNT)
	errx(EXIT_FAILURE, "dwarf_add_directory_decl failed: %s",
	    dwarf_errmsg(-1));

filendx = dwarf_add_file_decl(dbg, "bar.c", dir, 0, 1234, &de);
if (filendx == DW_DLV_NOCOUNT)
	errx(EXIT_FAILURE, "dwarf_add_file_decl failed: %s",
	    dwarf_errmsg(-1));

if (dwarf_lne_set_address(dbg, 0x4012b0, 12, &de) != DW_DLV_OK)
	errx(EXIT_FAILURE, "dwarf_lne_set_address failed: %s",
	    dwarf_errmsg(-1));

if (dwarf_add_line_entry(dbg, filendx, 10, 258, 0, 1, 1, &de) !=
    DW_DLV_OK)
	errx(EXIT_FAILURE, "dwarf_add_line_entry failed: %s",
	    dwarf_errmsg(-1));

ERRORS

Function dwarf_add_line_entry() can fail with:

[DW_DLE_ARGUMENT]: Argument dbg was NULL.
[DW_DLE_ARGUMENT]: The function dwarf_lne_set_address(3) was not called before calling this function.
[DW_DLE_MEMORY]: An out of memory condition was encountered during the execution of the function.