Copyright (c) 2011 Kai Wang
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
Id: dwarf_get_weaks.3 3963 2022-03-12 16:07:32Z jkoshy
.Dd April 10, 2011 .Dt DWARF_GET_WEAKS 3 .Os .Sh NAME .Nm dwarf_get_weaks , .Nm dwarf_weak_cu_offset , .Nm dwarf_weak_die_offset , .Nm dwarf_weak_name_offsets , .Nm dwarf_weakname .Nd retrieve information about weak symbols .Sh LIBRARY .Lb libdwarf .Sh SYNOPSIS n libdwarf.h .Ft int .Fo dwarf_get_weaks .Fa "Dwarf_Debug dbg" .Fa "Dwarf_Weak **weaks" .Fa "Dwarf_Signed *nweaks" .Fa "Dwarf_Error *err" .Fc .Ft int .Fo dwarf_weak_cu_offset .Fa "Dwarf_Weak weak" .Fa "Dwarf_Off *cu_offset" .Fa "Dwarf_Error *err" .Fc .Ft int .Fo dwarf_weak_die_offset .Fa "Dwarf_Weak weak" .Fa "Dwarf_Off *die_offset" .Fa "Dwarf_Error *err" .Fc .Ft int .Fo dwarf_weak_name_offsets .Fa "Dwarf_Weak weak" .Fa "char **name" .Fa "Dwarf_Off *die_offset" .Fa "Dwarf_Off *cu_die_offset" .Fa "Dwarf_Error *err" .Fc .Ft int .Fo dwarf_weakname .Fa "Dwarf_Weak weak" .Fa "char **name" .Fa "Dwarf_Error *err" .Fc .Sh DESCRIPTION These functions retrieve information about weak symbols from the lookup tables in the (SGI-specific) .Dq ".debug_weaknames" section. Information about weak symbols is returned using opaque descriptors of type .Vt Dwarf_Weak . Applications need to use the functions described below to retrieve the name and offset information contained in these descriptors.
p Function .Fn dwarf_get_weaks retrieves descriptors for all the weak symbols associated with the DWARF debug context specified by argument .Fa dbg . The argument .Fa weaks should point to a location that will be set to a pointer to an array of .Vt Dwarf_Weak descriptors. The argument .Fa nweaks should point to a location that will be set to the number of descriptors returned.
p Function .Fn dwarf_weak_cu_offset returns the offset, relative to the .Dq ".debug_info" section, of the compilation unit that contains the debugging information entry associated with the argument .Fa weak . Argument .Fa cu_offset should point to a location that will hold the returned offset.
p Function .Fn dwarf_weak_die_offset retrieves the offset, relative to the .Dq ".debug_info" section, of the debugging information entry associated with the argument .Fa weak , and stores it into the location pointed to by the argument .Fa die_offset .
p Function .Fn dwarf_weak_name_offsets retrieves the name and offsets for the debugging information entry for argument .Fa weak . Argument .Fa name should point to a location which will be set to a pointer to a NUL-terminated string containing the name of the associated debugging information entry. Argument .Fa die_offset should point to a location which will be set to the offset, relative to the .Dq ".debug_info" section, of the associated debugging information entry. Argument .Fa cu_die_offset should point to a location which will be set to the offset, relative to the .Dq ".debug_info" section, of the first debugging information entry in the compilation unit associated with argument .Fa weak .
p Function .Fn dwarf_weakname sets the location pointed to by argument .Fa name to a pointer to a NUL-terminated string holding the name of the debugging information entry associated with the argument .Fa weak . .Ss Memory Management The memory area used for the array of .Vt Dwarf_Weak descriptors returned in argument .Fa weaks by function .Fn dwarf_get_weaks is owned by the .Lb libdwarf . Application code should not attempt to directly free this pointer. Portable code should instead use the function .Xr dwarf_weaks_dealloc 3 to indicate that the memory area may be freed.
p The memory area used for the string returned in the .Fa name argument to functions .Fn dwarf_weak_name_offsets and .Fn dwarf_weakname is owned by the .Lb libdwarf . Portable code should indicate that the memory area can be freed using the .Xr dwarf_dealloc 3 function. .Ss Error Returns If argument .Fa err is not .Dv NULL , these functions will use it to store error information, in case of an error. .Sh RETURN VALUES On success, these functions returns .Dv DW_DLV_OK . In case of an error, they return .Dv DW_DLV_ERROR and set the argument .Fa err . .Sh ERRORS These functions may fail with the following errors: l -tag -width ".Bq Er DW_DLE_ARGUMENT" t Bq Er DW_DLE_ARGUMENT One of the arguments .Va cu_die_offset , .Va cu_offset , .Va dbg , .Va die_offset , .Va weak , .Va weaks , .Va name , or .Va nweaks was .Dv NULL . t Bq Er DW_DLE_NO_ENTRY The DWARF debugging context referenced by argument .Fa dbg did not contain information about weak symbols. .El .Sh SEE ALSO .Xr dwarf 3 , .Xr dwarf_get_cu_die_offset_given_cu_header_offset 3 , .Xr dwarf_weaks_dealloc 3
Indexes created Tue Jun 23 00:25:03 UTC 2026