DWARF_GET_ARANGES(3)

DWARF_GET_ARANGES(3) | Library Functions Manual | DWARF_GET_ARANGES(3)

# NAME

`dwarf_get_aranges` — retrieve program address space mappings

# LIBRARY

DWARF Access Library (libdwarf, -ldwarf)

# SYNOPSIS

`#include <libdwarf.h>`

int
`dwarf_get_aranges`(Dwarf_Debug dbg, Dwarf_Arange **ar_list, Dwarf_Signed *ar_cnt, Dwarf_Error *err);

# DESCRIPTION

The function `dwarf_get_aranges`() retrieves address range information from the “.debug_aranges” DWARF section. Information about address ranges is returned using opaque descriptors of type Dwarf_Arange,

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

Argument ar_list should point to a location which will be set to a pointer to an array of Dwarf_Arange descriptors.

Argument ar_cnt should point to a location which will be set to the number of descriptors returned.

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

## Memory Management

The memory area used for the array returned in argument ar_list is owned by DWARF Access Library (libdwarf, -ldwarf). Application code should not attempt to directly free this area. Portable applications should instead use dwarf_dealloc(3) to indicate that the memory area may be freed.

# RETURN VALUES

Function `dwarf_get_aranges`() returns `DW_DLV_OK` when it succeeds. It returns `DW_DLV_NO_ENTRY` if there is no “.debug_aranges” section associated with the specified debugging context. In case of an error, it returns `DW_DLV_ERROR` and sets the argument err.

# EXAMPLES

To loop through all the address lookup table entries, use:

    Dwarf_Debug dbg;
    Dwarf_Addr start;
    Dwarf_Arange *aranges;
    Dwarf_Off die_off;
    Dwarf_Signed i, cnt;
    Dwarf_Unsigned length;
    Dwarf_Error de;

    if (dwarf_get_aranges(dbg, &aranges, &cnt, &de) != DW_DLV_OK)
    	errx(EXIT_FAILURE, "dwarf_get_aranges: %s",
    	    dwarf_errmsg(de));

    for (i = 0; i < cnt; i++) {
    	if (dwarf_get_arange_info(aranges[i], &start, &length,
    	    &die_off, &de) != DW_DLV_OK) {
    		warnx("dwarf_get_arange_info: %s",
    		    dwarf_errmsg(de));
    		continue;
    	}
    	/* Do something with the returned information. */
    }

# ERRORS

Function `dwarf_get_aranges`() can fail with:

[`DW_DLE_ARGUMENT`]
  One of the arguments dbg, ar_list or ar_cnt was `NULL`.
[`DW_DLE_NO_ENTRY`]
  The debugging context dbg did not contain a “.debug_aranges” string section.

# SEE ALSO

dwarf(3), dwarf_get_arange(3), dwarf_get_arange_cu_header_offset(3), dwarf_get_arange_info(3), dwarf_get_cu_die_offset(3)

November 9, 2011 | NetBSD 11.0