DWARF_ADD_LINE_ENTRY(3) | Library Functions Manual | DWARF_ADD_LINE_ENTRY(3)

# 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.

# 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.

# EXAMPLE

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));

# SEE ALSO

dwarf(3), dwarf_add_directory_decl(3), dwarf_add_file_decl(3), dwarf_lne_end_sequence(3), dwarf_lne_set_address(3), dwarf_producer_init(3), dwarf_producer_init_b(3)

June 30, 2013 | NetBSD 9.3