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DWARF_GET_SECTION_BYTES(3) FreeBSD Library Functions Manual
NAME
dwarf_get_section_bytes - retrieve ELF section byte streams
LIBRARY
DWARF Access Library (libdwarf, -ldwarf)
SYNOPSIS
#include <libdwarf.h>
Dwarf_Ptr
dwarf_get_section_bytes(Dwarf_P_Debug dbg, Dwarf_Signed dwarf_section,
Dwarf_Signed *elf_section_index, Dwarf_Unsigned *length,
Dwarf_Error *err);
DESCRIPTION
Function dwarf_get_section_bytes() returns the ELF section byte streams
generated by a prior call to function dwarf_transform_to_disk_form(3).
Each call to function dwarf_get_section_bytes() will return the byte
stream for one ELF section. The first call to this function will always
return the first ELF section, and the subsequent calls will return the
rest of sections in the order when they were generated, until the last
one. The total number of sections generated is returned by the function
dwarf_transform_to_disk_form(3).
Argument dbg should reference a DWARF producer instance allocated using
the functions dwarf_producer_init(3) or dwarf_producer_init_b(3).
Argument dwarf_section is currently ignored.
Argument elf_section_index should point to a location which will be set
to the section index value of the returned ELF section.
Argument length should point to a location which will hold the length in
bytes of the returned ELF section.
If argument err is not NULL, it will be used to store error information
in case of an error.
Memory Management
The memory areas used for the returned ELF section byte streams should be
freed using the function dwarf_producer_finish().
RETURN VALUES
On success, function dwarf_get_section_bytes() returns a pointer to a ELF
section byte stream. In case of an error, function
dwarf_get_section_bytes() will return NULL and set the argument err.
EXAMPLES
To generate and retrieve ELF section byte streams, use:
Dwarf_P_Debug dbg;
Dwarf_Signed count, i, sec_index;
Dwarf_Unsigned len;
Dwarf_Ptr bytes;
Dwarf_Error de;
dwarf_errmsg(-1));
return;
}
/* Retrieve section data. */
for (i = 0; i < count; i++) {
bytes = dwarf_get_section_bytes(dbg, i, &sec_index, &len,
&de);
if (bytes == NULL) {
warnx("dwarf_get_section_bytes failed: %s",
dwarf_errmsg(-1));
continue;
}
/* ... use the returned byte stream ... */
}
/* Release resources. */
dwarf_producer_finish(dbg, &de);
ERRORS
Function dwarf_get_section_bytes() can fail with:
[DW_DLE_ARGUMENT] One of the arguments dbg, elf_section_index, or
length was NULL.
[DW_DLE_NO_ENTRY] There were no more ELF sections to retrieve, or the
function was called before a call to
dwarf_transform_to_disk_form(3).
SEE ALSO
dwarf(3), dwarf_producer_finish(3), dwarf_producer_init(3),
dwarf_producer_init_b(3), dwarf_reset_section_bytes(3),
dwarf_transform_to_disk_form(3)
FreeBSD 14.0-RELEASE-p11 August 26, 2011 FreeBSD 14.0-RELEASE-p11