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Diffstat (limited to 'rtemstoolkit/elftoolchain/libdwarf/dwarf_get_abbrev.3')
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diff --git a/rtemstoolkit/elftoolchain/libdwarf/dwarf_get_abbrev.3 b/rtemstoolkit/elftoolchain/libdwarf/dwarf_get_abbrev.3 new file mode 100644 index 0000000..afb5468 --- /dev/null +++ b/rtemstoolkit/elftoolchain/libdwarf/dwarf_get_abbrev.3 @@ -0,0 +1,179 @@ +.\" 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_abbrev.3 2071 2011-10-27 03:20:00Z jkoshy $ +.\" +.Dd March 27, 2011 +.Os +.Dt DWARF_GET_ABBREV 3 +.Sh NAME +.Nm dwarf_get_abbrev +.Nd retrieve abbreviation information +.Sh LIBRARY +.Lb libdwarf +.Sh SYNOPSIS +.In libdwarf.h +.Ft int +.Fo dwarf_get_abbrev +.Fa "Dwarf_Debug dbg" +.Fa "Dwarf_Unsigned offset" +.Fa "Dwarf_Abbrev *ret_abbrev" +.Fa "Dwarf_Unsigned *length" +.Fa "Dwarf_Unsigned *attr_count" +.Fa "Dwarf_Error *err" +.Fc +.Sh DESCRIPTION +Function +.Fn dwarf_get_abbrev +retrieves information about an abbreviation from the DWARF abbreviations +section, +.Dq ".debug_abbrev" . +Abbreviation information is returned using an opaque descriptor +of type +.Vt Dwarf_Abbrev . +The returned +.Vt Dwarf_Abbrev +descriptor may then be passed to the other abbreviation related APIs +in the DWARF(3) API to retrieve specific information about the +abbreviation. +.Pp +Argument +.Ar dbg +should reference a DWARF debug context allocated using +.Xr dwarf_init 3 . +.Pp +Argument +.Ar offset +should be an offset, relative to the +.Dq ".debug_abbrev" +section, to the start of an abbreviation entry. +.Pp +Argument +.Ar ret_abbrev +should point to a location that will hold a pointer to the +returned +.Vt Dwarf_Abbrev +descriptor. +.Pp +Argument +.Ar length +should point to a location that will hold the number of bytes used +by the abbrevation in the DWARF +.Dq ".debug_abbrev" +section. +.Pp +Argument +.Ar attr_count +should point to a location that will hold the number of +attributes in the abbrevation. +.Pp +If argument +.Ar err +is not NULL, it will be used to store error information in case of an +error. +.Ss Memory Management +The memory area used for the +.Vt Dwarf_Abbrev +descriptor returned in argument +.Ar ret_abbrev +is allocated by the +.Lb libdwarf . +Application code should use function +.Fn dwarf_dealloc +with the allocation type +.Dv DW_DLA_ABBREV +to free the memory area when the +.Vt Dwarf_Abbrev +descriptor is no longer needed. +.Ss Application Programming Notes +The last abbreviation entry in a standard DWARF abbreviation section +will have a special length value of 1. +.Sh RETURN VALUES +Function +.Fn dwarf_get_abbrev +returns +.Dv DW_DLV_OK +when it succeeds. +It returns +.Dv DW_DLV_NO_ENTRY +if there is no abbreviation information at offset +.Ar offset . +In case of an error, it returns +.Dv DW_DLV_ERROR +and sets the argument +.Ar err . +.Sh ERRORS +Function +.Fn dwarf_get_abbrev +can fail with: +.Bl -tag -width ".Bq Er DW_DLE_NO_ENTRY" +.It Bq Er DW_DLE_ARGUMENT +One of the arguments +.Ar dbg , +.Ar ret_abbrev , +.Ar length +or +.Ar attr_count +was NULL. +.It Bq Er DW_DLE_NO_ENTRY +There is no abbreviation information at offset +.Ar offset . +.El +.Sh EXAMPLE +To loop through all the abbreviation information associated with +a DWARF debug context, use: +.Bd -literal -offset indent +Dwarf_Debug dbg; +Dwarf_Abbrev ab; +Dwarf_Off aboff; +Dwarf_Unsigned length, attr_count; +Dwarf_Half tag; +Dwarf_Error de; +int ret; + +while ((ret = dwarf_next_cu_header(dbg, NULL, NULL, &aboff, + NULL, NULL, &de)) == DW_DLV_OK) { + while ((ret = dwarf_get_abbrev(re->dbg, aboff, &ab, &length, + &attr_count, &de)) == DW_DLV_OK) { + if (length == 1) /* Last entry. */ + break; + aboff += length; + if (dwarf_get_abbrev_tag(ab, &tag, &de) != DW_DLV_OK) { + warnx("dwarf_get_abbrev_tag failed: %s", + dwarf_errmsg(de)); + continue; + } + if (ret != DW_DLV_OK) + warnx("dwarf_get_abbrev: %s", dwarf_errmsg(de)); +} +if (ret == DW_DLV_ERROR) + warnx("dwarf_next_cu_header: %s", dwarf_errmsg(de)); +.Ed +.Sh SEE ALSO +.Xr dwarf 3 , +.Xr dwarf_dealloc 3 , +.Xr dwarf_get_abbrev_tag 3 , +.Xr dwarf_get_abbrev_code 3 , +.Xr dwarf_get_abbrev_children_flag 3 , +.Xr dwarf_get_abbrev_entry 3 |