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Diffstat (limited to 'rtemstoolkit/elftoolchain/libdwarf/dwarf_expand_frame_instructions.3')
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diff --git a/rtemstoolkit/elftoolchain/libdwarf/dwarf_expand_frame_instructions.3 b/rtemstoolkit/elftoolchain/libdwarf/dwarf_expand_frame_instructions.3 new file mode 100644 index 0000000..7bcd105 --- /dev/null +++ b/rtemstoolkit/elftoolchain/libdwarf/dwarf_expand_frame_instructions.3 @@ -0,0 +1,182 @@ +.\" 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_expand_frame_instructions.3 3181 2015-04-10 13:22:51Z emaste $ +.\" +.Dd November 9, 2011 +.Os +.Dt DWARF_EXPAND_FRAME_INSTRUCTIONS 3 +.Sh NAME +.Nm dwarf_expand_frame_instructions +.Nd expand frame instructions +.Sh LIBRARY +.Lb libdwarf +.Sh SYNOPSIS +.In libdwarf.h +.Ft int +.Fo dwarf_expand_frame_instructions +.Fa "Dwarf_Cie cie" +.Fa "Dwarf_Ptr instructions" +.Fa "Dwarf_Unsigned len" +.Fa "Dwarf_Frame_Op **ret_ops" +.Fa "Dwarf_Signed *ret_opcnt" +.Fa "Dwarf_Error *error" +.Fc +.Sh DESCRIPTION +Function +.Fn dwarf_expand_frame_instructions +translates DWARF frame instruction bytes into an array of +.Vt Dwarf_Frame_Op +descriptors. +.Pp +Argument +.Ar cie +should reference the CIE descriptor associated with the instructions +to be translated. +.Pp +Arugment +.Ar instructions +should point to an array of frame instruction bytes, as +returned by the functions +.Xr dwarf_get_cie_info 3 +or +.Xr dwarf_get_fde_instr_bytes 3 . +.Pp +Argument +.Ar len +should specify the number of the frame instruction bytes to be +translated. +.Pp +Argument +.Ar ret_ops +should point to a location that will be set to a pointer to +an array of translated +.Vt Dwarf_Frame_Op +descriptors. +.Pp +Argument +.Ar ret_opcnt +should point to a location that will hold the total number of the +returned descriptors. +.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 descriptor array returned in argument +.Ar ret_ops +is allocated by +.Lb libdwarf . +Application code should use function +.Xr dwarf_dealloc 3 +with type +.Dv DW_DLA_FRAME_BLOCK +to free the memory area when the descriptor array is no longer needed. +.Sh RETURN VALUES +Function +.Fn dwarf_expand_frame_instructions +returns +.Dv DW_DLV_OK +when it succeeds. +In case of an error, it returns +.Dv DW_DLV_ERROR +and sets the argument +.Ar err . +.Sh ERRORS +Function +.Fn dwarf_expand_frame_instructions +can fail with: +.Bl -tag -width ".Bq Er DW_DLE_ARGUMENT" +.It Bq Er DW_DLE_ARGUMENT +One of the arguments +.Ar cie , +.Ar instructions , +.Ar ret_ops +or +.Ar ret_opcnt +was NULL. +.It Bq Er DW_DLE_ARGUMENT +Argument +.Ar len +was 0. +.It Bq Er DW_DLE_MEMORY +An out of memory condition was encountered during the execution of +this function. +.It Bq Er DW_DLE_FRAME_INSTR_EXEC_ERROR +An unknown instruction was found in the instruction bytes provided +in argument +.Ar instructions . +.El +.Sh EXAMPLE +To retrieve and expand the frame instructions for a given FDE +descriptor, use: +.Bd -literal -offset indent +Dwarf_Dbg dbg; +Dwarf_Cie cie; +Dwarf_Fde fde; +Dwarf_Ptr fde_inst; +Dwarf_Unsigned fde_instlen; +Dwarf_Frame_Op *ops; +Dwarf_Signed opcnt; +Dwarf_Error de; + +/* ... assuming `dbg` references a valid DWARF debugging context, + `fde` references a valid FDE descriptor and `cie` holds the CIE + descriptor associated with the FDE descriptor ... */ + +if (dwarf_get_fde_instr_bytes(fde, &fde_inst, &fde_instlen, + &de) != DW_DLV_OK) + errx(EXIT_FAILURE, "dwarf_get_fde_instr_bytes failed: %s", + dwarf_errmsg(de)); + +if (dwarf_expand_frame_instructions(cie, fde_inst, fde_instlen, + &ops, &opcnt, &de) != DW_DLV_OK) + errx(EXIT_FAILURE, + "dwarf_expand_frame_instructions failed: %s", + dwarf_errmsg(de)); + +for (i = 0; i < opcnt; i++) { + /* ... use ops[i] ... */ +} + +/* Free the memory area when no longer needed. */ +dwarf_dealloc(dbg, ops, DW_DLA_FRAME_BLOCK); +.Ed +.Sh SEE ALSO +.Xr dwarf 3 , +.Xr dwarf_frame_instructions_dealloc 3 , +.Xr dwarf_get_cie_info 3 , +.Xr dwarf_get_cie_index 3 , +.Xr dwarf_get_cie_of_fde , +.Xr dwarf_get_fde_at_pc 3 , +.Xr dwarf_get_fde_info_for_all_regs 3 , +.Xr dwarf_get_fde_info_for_all_regs3 3 , +.Xr dwarf_get_fde_info_for_cfa_reg3 3 , +.Xr dwarf_get_fde_info_for_reg 3 , +.Xr dwarf_get_fde_info_for_reg3 3 , +.Xr dwarf_get_fde_instr_bytes 3 , +.Xr dwarf_get_fde_list 3 , +.Xr dwarf_get_fde_list_eh 3 , +.Xr dwarf_get_fde_n 3 |