forked from osmocom/wireshark
![Gerald Combs](/assets/img/avatar_default.png)
Convert links, source code blocks, and admonitions. Change-Id: I50c8daa19a115c23f7501b91dbfd904779a609c9 Reviewed-on: https://code.wireshark.org/review/25720 Petri-Dish: Gerald Combs <gerald@wireshark.org> Tested-by: Petri Dish Buildbot Reviewed-by: Gerald Combs <gerald@wireshark.org>
688 lines
24 KiB
C
688 lines
24 KiB
C
/******************************************************************************
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* Copyright (C) 2010-2012 Lua.org, PUC-Rio. All rights reserved.
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*
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* Permission is hereby granted, free of charge, to any person obtaining
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* a copy of this software and associated documentation files (the
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* "Software"), to deal in the Software without restriction, including
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* without limitation the rights to use, copy, modify, merge, publish,
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* distribute, sublicense, and/or sell copies of the Software, and to
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* permit persons to whom the Software is furnished to do so, subject to
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* the following conditions:
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*
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* The above copyright notice and this permission notice shall be
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* included in all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
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* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
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* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
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* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
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* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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******************************************************************************/
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/*
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** {======================================================
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** Library for packing/unpacking structures.
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** See Copyright Notice above.
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**
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** Small changes were made by Hadriel Kaplan - those changes
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** are in the Public Domain.
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**
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** Some changes are based on a patch to struct.h from
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** Flemming Madsen, from here:
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** http://lua-users.org/lists/lua-l/2009-10/msg00572.html
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** In particular, these changes from him:
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** -Can handle 'long long' integers (i8 / I8); though they're converted to doubles
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** -Can insert/specify padding anywhere in a struct. ('X' eg. when a string is following a union)
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** -Can report current offset in both pack and unpack ('=')
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** -Can mask out return values when you only want to calculate sizes or unmarshal pascal-style strings. '(' & ')'
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**
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** Changes I made:
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** -Added support for Int64/UInt64 being packed/unpacked, using 'e'/'E'
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** -Made it follow Wireshark's conventions so we could get API docs
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** =======================================================
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*/
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/*
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** Valid formats:
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** > - big endian
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** < - little endian
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** ![num] - alignment
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** x[num] - pad num bytes, default 1
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** X[num] - pad to num align, default MAXALIGN
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**
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** Following are system-dependent sizes:
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** i/I - signed/unsigned int
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** l/L - signed/unsigned long
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** f - float
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** T - size_t
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**
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** Following are system-independent sizes:
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** b/B - signed/unsigned byte
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** h/H - signed/unsigned short
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** in/In - signed/unsigned integer of size `n' bytes
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Note: Unpack of i/I is done to a Lua_number, typically a double,
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so unpacking a 64-bit field (i8/I8) will lose precision.
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Use e/E to unpack into a Wireshark Int64/UInt64 object/userdata instead.
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** e/E - signed/unsigned eight-byte Integer (64bits, long long), to/from Int64/UInt64 object
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** d - double
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** cn - sequence of `n' chars (from/to a string); when packing, n==0 means
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the whole string; when unpacking, n==0 means use the previous
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read number as the string length
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** s - zero-terminated string
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** ' ' - ignored
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** '(' ')' - stop assigning items. ')' start assigning (padding when packing)
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** '=' - return current position / offset
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*/
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#include "config.h"
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#include <assert.h>
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#include <limits.h>
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#include <stddef.h>
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#include <string.h>
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#include <stdio.h>
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#include "wslua.h"
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/* WSLUA_MODULE Struct Binary encode/decode support
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The Struct class offers basic facilities to convert Lua values to and from C-style structs
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in binary Lua strings. This is based on Roberto Ierusalimschy's Lua struct library found
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in http://www.inf.puc-rio.br/~roberto/struct/, with some minor modifications as follows:
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* Added support for `Int64`/`UInt64` being packed/unpacked, using 'e'/'E'.
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* Can handle 'long long' integers (i8 / I8); though they're converted to doubles.
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* Can insert/specify padding anywhere in a struct. ('X' eg. when a string is following a union).
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* Can report current offset in both `pack` and `unpack` ('`=`').
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* Can mask out return values when you only want to calculate sizes or unmarshal
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pascal-style strings using '`(`' & '`)`'.
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All but the first of those changes are based on an email from Flemming Madsen, on the lua-users
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mailing list, which can be found http://lua-users.org/lists/lua-l/2009-10/msg00572.html[here].
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The main functions are `Struct.pack`, which packs multiple Lua values into a struct-like
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Lua binary string; and `Struct.unpack`, which unpacks multiple Lua values from a given
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struct-like Lua binary string. There are some additional helper functions available as well.
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All functions in the Struct library are called as static member functions, not object methods,
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so they are invoked as "Struct.pack(...)" instead of "object:pack(...)".
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The fist argument to several of the `Struct` functions is a format string, which describes
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the layout of the structure. The format string is a sequence of conversion elements, which
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respect the current endianness and the current alignment requirements. Initially, the
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current endianness is the machine's native endianness and the current alignment requirement
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is 1 (meaning no alignment at all). You can change these settings with appropriate directives
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in the format string.
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The supported elements in the format string are as follows:
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* `$$ $$' (empty space) ignored.
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* `++!++__n__' flag to set the current alignment requirement to 'n' (necessarily a power of 2);
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an absent 'n' means the machine's native alignment.
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* `++>++' flag to set mode to big endian (i.e., network-order).
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* `++<++' flag to set mode to little endian.
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* `++x++' a padding zero byte with no corresponding Lua value.
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* `++b++' a signed char.
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* `++B++' an unsigned char.
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* `++h++' a signed short (native size).
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* `++H++' an unsigned short (native size).
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* `++l++' a signed long (native size).
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* `++L++' an unsigned long (native size).
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* `++T++' a size_t (native size).
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* `++i++__n__' a signed integer with 'n' bytes. An absent 'n' means the native size of an int.
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* `++I++__n__' like `++i++__n__' but unsigned.
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* `++e++' signed 8-byte Integer (64-bits, long long), to/from a +Int64+ object.
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* `++E++' unsigned 8-byte Integer (64-bits, long long), to/from a +UInt64+ object.
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* `++f++' a float (native size).
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* `++d++' a double (native size).
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* `++s++' a zero-terminated string.
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* `++c++__n__' a sequence of exactly 'n' chars corresponding to a single Lua string. An absent 'n'
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means 1. When packing, the given string must have at least 'n' characters (extra
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characters are discarded).
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* `++c0++' this is like `++c++__n__', except that the 'n' is given by other means: When packing, 'n' is
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the length of the given string; when unpacking, 'n' is the value of the previous unpacked
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value (which must be a number). In that case, this previous value is not returned.
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* `++x++__n__' pad to 'n' number of bytes, default 1.
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* `++X++__n__' pad to 'n' alignment, default MAXALIGN.
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* `++(++' to stop assigning items, and `++)++' start assigning (padding when packing).
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* `++=++' to return the current position / offset.
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[NOTE]
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====
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Using `i`, `I`, `h`, `H`, `l`, `L`, `f`, and `T` is strongly discouraged, as those sizes
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are system-dependent. Use the explicitly sized variants instead, such as `i4` or `E`.
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Unpacking of `i`/`I` is done to a Lua number, a double-precision floating point,
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so unpacking a 64-bit field (`i8`/`I8`) will lose precision.
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Use `e`/`E` to unpack into a Wireshark `Int64`/`UInt64` object instead.
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====
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@since 1.11.3
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*/
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/* The following line is here so that make-reg.pl does the right thing. This 'Struct' class
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isn't really a class, so it doesn't have the checkStruct/pushStruct/etc. functions
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the following macro would generate; but it does need to be registered and such, so...
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WSLUA_CLASS_DEFINE_BASE(Struct,NOP,0);
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*/
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/* basic integer type - yes this is system-specific size - it's meant to be */
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#if !defined(STRUCT_INT)
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#define STRUCT_INT long
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#endif
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typedef STRUCT_INT Inttype;
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/* corresponding unsigned version */
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typedef unsigned STRUCT_INT Uinttype;
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/* maximum size (in bytes) for integral types */
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#define MAXINTSIZE 32
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/* is 'x' a power of 2? */
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#define isp2(x) ((x) > 0 && ((x) & ((x) - 1)) == 0)
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/* dummy structure to get padding/alignment requirements */
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struct cD {
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gchar c;
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gdouble d;
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};
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#define PADDING (sizeof(struct cD) - sizeof(gdouble))
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#define MAXALIGN (PADDING > sizeof(int) ? PADDING : sizeof(int))
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/* endian options */
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#define BIG 0
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#define LITTLE 1
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/* trick to determine native endianness of system */
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static union {
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int dummy;
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gchar endian;
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} const native = {1};
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/* settings info */
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typedef struct Header {
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int endian;
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int align;
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gboolean noassign;
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} Header;
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/* For options that take a number argument, gets the number */
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static int getnum (const gchar **fmt, int df) {
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if (!g_ascii_isdigit(**fmt)) /* no number? */
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return df; /* return default value */
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else {
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int a = 0;
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do {
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a = a*10 + *((*fmt)++) - '0';
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} while (g_ascii_isdigit(**fmt));
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return a;
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}
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}
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#define defaultoptions(h) ((h)->endian = native.endian, (h)->align = 1, (h)->noassign = FALSE)
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/* gets size (number of bytes) for a given type */
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static size_t optsize (lua_State *L, gchar opt, const gchar **fmt) {
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switch (opt) {
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case 'B': case 'b': return sizeof(gchar);
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case 'H': case 'h': return sizeof(gshort);
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case 'L': case 'l': return sizeof(glong);
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case 'E': case 'e': return sizeof(gint64);
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case 'T': return sizeof(size_t);
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case 'f': return sizeof(gfloat);
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case 'd': return sizeof(gdouble);
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case 'x': return getnum(fmt, 1);
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case 'X': return getnum(fmt, MAXALIGN);
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case 'c': return getnum(fmt, 1);
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case 'i': case 'I': {
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int sz = getnum(fmt, sizeof(int));
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if (sz > MAXINTSIZE)
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luaL_error(L, "integral size %d is larger than limit of %d",
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sz, MAXINTSIZE);
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return sz;
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}
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case 's': case ' ':
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case '<': case '>':
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case '(': case ')':
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case '!': case '=':
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return 0; /* these cases do not have a size */
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default: {
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const gchar *msg = lua_pushfstring(L, "invalid format option [%c]", opt);
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return luaL_argerror(L, 1, msg);
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}
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}
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}
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/*
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** return number of bytes needed to align an element of size 'size'
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** at current position 'len'
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*/
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static int gettoalign (size_t len, Header *h, int opt, size_t size) {
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if (size == 0 || opt == 'c' || opt == 's') return 0;
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if (size > (size_t)h->align)
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size = h->align; /* respect max. alignment */
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return (int)((size - (len & (size - 1))) & (size - 1));
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}
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/*
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** options to control endianness and alignment settings
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*/
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static void controloptions (lua_State *L, int opt, const gchar **fmt,
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Header *h) {
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switch (opt) {
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case ' ': return; /* ignore white spaces */
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case '>': h->endian = BIG; return;
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case '<': h->endian = LITTLE; return;
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case '(': h->noassign = TRUE; return;
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case ')': h->noassign = FALSE; return;
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case '!': {
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int a = getnum(fmt, MAXALIGN);
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if (!isp2(a))
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luaL_error(L, "alignment %d is not a power of 2", a);
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h->align = a;
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return;
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}
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default: {
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const char *msg = lua_pushfstring(L, "invalid format option '%c'", opt);
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luaL_argerror(L, 1, msg);
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}
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}
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}
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/* Encodes a Lua number as an integer of given size and endianness into a string struct */
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static void putinteger (lua_State *L, luaL_Buffer *b, int arg, int endian,
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int size) {
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lua_Number n = luaL_checknumber(L, arg);
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/* this one's not system dependent size - it's a long long */
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gint64 value;
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gchar buff[MAXINTSIZE];
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if (n < 0)
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value = (guint64)(gint64)n;
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else
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value = (guint64)n;
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if (endian == LITTLE) {
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int i;
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for (i = 0; i < size; i++) {
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buff[i] = (value & 0xff);
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value >>= 8;
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}
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}
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else {
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int i;
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for (i = size - 1; i >= 0; i--) {
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buff[i] = (value & 0xff);
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value >>= 8;
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}
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}
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luaL_addlstring(b, buff, size);
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}
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/* corrects endianness - usually done by other functions themselves, but is
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* used for float/doubles, since on some platforms they're endian'ed as well
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*/
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static void correctbytes (gchar *b, int size, int endian) {
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if (endian != native.endian) {
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int i = 0;
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while (i < --size) {
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gchar temp = b[i];
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b[i++] = b[size];
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b[size] = temp;
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}
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}
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}
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WSLUA_CONSTRUCTOR Struct_pack (lua_State *L) {
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/* Returns a string containing the values arg1, arg2, etc. packed/encoded according to the format string. */
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#define WSLUA_ARG_Struct_pack_FORMAT 1 /* The format string */
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#define WSLUA_ARG_Struct_pack_VALUE 2 /* One or more Lua value(s) to encode, based on the given format. */
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luaL_Buffer b;
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const char *fmt = wslua_checkstring_only(L, WSLUA_ARG_Struct_pack_FORMAT);
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Header h;
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int poscnt = 0;
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int posBuf[10];
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int arg = 2;
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size_t totalsize = 0;
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defaultoptions(&h);
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lua_pushnil(L); /* mark to separate arguments from string buffer */
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luaL_buffinit(L, &b);
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while (*fmt != '\0') {
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int opt = *fmt++;
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size_t size = optsize(L, opt, &fmt);
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int toalign = gettoalign(totalsize, &h, opt, size);
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totalsize += toalign;
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while (toalign-- > 0) luaL_addchar(&b, '\0');
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if (opt == 'X') size = 0; /* 'X' is about alignment, not size */
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if (h.noassign && size) opt = 'x'; /* for pack, "(i4)" is the same as "x4" */
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switch (opt) {
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case 'b': case 'B': case 'h': case 'H':
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case 'l': case 'L': case 'T': case 'i': case 'I': { /* integer types */
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putinteger(L, &b, arg++, h.endian, (int)size);
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break;
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}
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case 'e': {
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Int64_pack(L, &b, arg++, h.endian == LITTLE);
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break;
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}
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case 'E': {
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UInt64_pack(L, &b, arg++, h.endian == LITTLE);
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break;
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}
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case 'x': case 'X': {
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size_t len = size;
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while (len-- > 0)
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luaL_addchar(&b, '\0');
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break;
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}
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case 'f': {
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gfloat f = (gfloat)luaL_checknumber(L, arg++);
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correctbytes((gchar *)&f, (int)size, h.endian);
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luaL_addlstring(&b, (gchar *)&f, size);
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break;
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}
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case 'd': {
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gdouble d = luaL_checknumber(L, arg++);
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correctbytes((gchar *)&d, (int)size, h.endian);
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luaL_addlstring(&b, (gchar *)&d, size);
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break;
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}
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case 'c': case 's': {
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size_t l;
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const gchar *s = luaL_checklstring(L, arg++, &l);
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if (size == 0) size = l;
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luaL_argcheck(L, l >= (size_t)size, arg, "string too short");
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luaL_addlstring(&b, s, size);
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if (opt == 's') {
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luaL_addchar(&b, '\0'); /* add zero at the end */
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size++;
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}
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break;
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}
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case '=': {
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if (poscnt < (int)(sizeof(posBuf)/sizeof(posBuf[0])))
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posBuf[poscnt++] = (int)totalsize + 1;
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break;
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}
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default: controloptions(L, opt, &fmt, &h);
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}
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totalsize += size;
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}
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luaL_pushresult(&b);
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for (arg = 0; arg < poscnt; arg++)
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lua_pushinteger(L, posBuf[arg]);
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WSLUA_RETURN(poscnt + 1); /* The packed binary Lua string, plus any positions due to '=' being used in format. */
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}
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/* Decodes an integer from a string struct into a Lua number, based on
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* given endianness and size. If the integer type is signed, this makes
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* the Lua number be +/- correctly as well.
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*/
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static lua_Number getinteger (const gchar *buff, int endian,
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int issigned, int size) {
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Uinttype l = 0;
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int i;
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if (endian == BIG) {
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for (i = 0; i < size; i++) {
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l <<= 8;
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l |= (Uinttype)(guchar)buff[i];
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}
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}
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else {
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for (i = size - 1; i >= 0; i--) {
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l <<= 8;
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l |= (Uinttype)(guchar)buff[i];
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}
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}
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if (!issigned)
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return (lua_Number)l;
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else { /* signed format */
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Uinttype mask = (Uinttype)(~((Uinttype)0)) << (size*8 - 1);
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if (l & mask) /* negative value? */
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l |= mask; /* signal extension */
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return (lua_Number)(Inttype)l;
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}
|
|
}
|
|
|
|
#define b_pushnumber(n) { if (!h.noassign) lua_pushnumber(L, (lua_Number)(n)); }
|
|
|
|
WSLUA_CONSTRUCTOR Struct_unpack (lua_State *L) {
|
|
/* Unpacks/decodes multiple Lua values from a given struct-like binary Lua string.
|
|
The number of returned values depends on the format given, plus an additional value of the position where it stopped reading is returned. */
|
|
#define WSLUA_ARG_Struct_unpack_FORMAT 1 /* The format string */
|
|
#define WSLUA_ARG_Struct_unpack_STRUCT 2 /* The binary Lua string to unpack */
|
|
#define WSLUA_OPTARG_Struct_unpack_BEGIN 3 /* The position to begin reading from (default=1) */
|
|
Header h;
|
|
const char *fmt = wslua_checkstring_only(L, WSLUA_ARG_Struct_unpack_FORMAT);
|
|
size_t ld;
|
|
const char *data = wslua_checklstring_only(L, WSLUA_ARG_Struct_unpack_STRUCT, &ld);
|
|
size_t pos = luaL_optinteger(L, WSLUA_OPTARG_Struct_unpack_BEGIN, 1) - 1;
|
|
defaultoptions(&h);
|
|
lua_settop(L, 2);
|
|
while (*fmt) {
|
|
int opt = *fmt++;
|
|
size_t size = optsize(L, opt, &fmt);
|
|
pos += gettoalign(pos, &h, opt, size);
|
|
luaL_argcheck(L, pos+size <= ld, 2, "data string too short");
|
|
|
|
if (opt == 'X') size = 0;
|
|
if (h.noassign && size > 0) {
|
|
/* if we're not assigning, and the opt type has a size, then loop again */
|
|
/* this will not be the case for control options, 'c0', 's', and '=' */
|
|
pos += size;
|
|
continue;
|
|
}
|
|
|
|
luaL_checkstack(L, 1, "too many results");
|
|
switch (opt) {
|
|
case 'b': case 'B': case 'h': case 'H':
|
|
case 'l': case 'L': case 'T': case 'i': case 'I': { /* integer types */
|
|
int issigned = g_ascii_islower(opt);
|
|
lua_Number res = getinteger(data+pos, h.endian, issigned, (int)size);
|
|
lua_pushnumber(L, res);
|
|
break;
|
|
}
|
|
case 'e': {
|
|
Int64_unpack(L, data+pos, h.endian == LITTLE);
|
|
break;
|
|
}
|
|
case 'E': {
|
|
UInt64_unpack(L, data+pos, h.endian == LITTLE);
|
|
break;
|
|
}
|
|
case 'x': case 'X': {
|
|
break;
|
|
}
|
|
case 'f': {
|
|
gfloat f;
|
|
memcpy(&f, data+pos, size);
|
|
correctbytes((gchar *)&f, sizeof(f), h.endian);
|
|
lua_pushnumber(L, f);
|
|
break;
|
|
}
|
|
case 'd': {
|
|
gdouble d;
|
|
memcpy(&d, data+pos, size);
|
|
correctbytes((gchar *)&d, sizeof(d), h.endian);
|
|
lua_pushnumber(L, d);
|
|
break;
|
|
}
|
|
case 'c': {
|
|
if (size == 0) {
|
|
if (!lua_isnumber(L, -1))
|
|
luaL_error(L, "format `c0' needs a previous size");
|
|
size = wslua_toguint32(L, -1);
|
|
lua_pop(L, 1);
|
|
luaL_argcheck(L, pos+size <= ld, 2, "data string too short");
|
|
}
|
|
if (!h.noassign)
|
|
lua_pushlstring(L, data+pos, size);
|
|
break;
|
|
}
|
|
case 's': {
|
|
const gchar *e = (const char *)memchr(data+pos, '\0', ld - pos);
|
|
if (e == NULL)
|
|
luaL_error(L, "unfinished string in data");
|
|
size = (e - (data+pos)) + 1;
|
|
if (!h.noassign)
|
|
lua_pushlstring(L, data+pos, size - 1);
|
|
break;
|
|
}
|
|
case '=': {
|
|
lua_pushinteger(L, pos + 1);
|
|
break;
|
|
}
|
|
default: controloptions(L, opt, &fmt, &h);
|
|
}
|
|
pos += size;
|
|
}
|
|
lua_pushinteger(L, pos + 1);
|
|
WSLUA_RETURN(lua_gettop(L) - 2); /* One or more values based on format, plus the position it stopped unpacking. */
|
|
}
|
|
|
|
|
|
WSLUA_CONSTRUCTOR Struct_size (lua_State *L) {
|
|
/* Returns the length of a binary string that would be consumed/handled by the given format string. */
|
|
#define WSLUA_ARG_Struct_size_FORMAT 1 /* The format string */
|
|
Header h;
|
|
const gchar *fmt = wslua_checkstring_only(L, WSLUA_ARG_Struct_size_FORMAT);
|
|
size_t pos = 0;
|
|
defaultoptions(&h);
|
|
while (*fmt) {
|
|
int opt = *fmt++;
|
|
size_t size = optsize(L, opt, &fmt);
|
|
pos += gettoalign(pos, &h, opt, size);
|
|
if (opt == 's')
|
|
luaL_argerror(L, 1, "option 's' has no fixed size");
|
|
else if (opt == 'c' && size == 0)
|
|
luaL_argerror(L, 1, "option 'c0' has no fixed size");
|
|
if (!g_ascii_isalnum(opt))
|
|
controloptions(L, opt, &fmt, &h);
|
|
pos += size;
|
|
}
|
|
lua_pushinteger(L, pos);
|
|
WSLUA_RETURN(1); /* The size number */
|
|
}
|
|
|
|
WSLUA_CONSTRUCTOR Struct_values (lua_State *L) {
|
|
/* Returns the number of Lua values contained in the given format string.
|
|
This will be the number of returned values from a call to Struct.unpack()
|
|
not including the extra return value of offset position. (i.e., Struct.values()
|
|
does not count that extra return value) This will also be the number of
|
|
arguments Struct.pack() expects, not including the format string argument. */
|
|
#define WSLUA_ARG_Struct_values_FORMAT 1 /* The format string */
|
|
Header h;
|
|
const gchar *fmt = wslua_checkstring_only(L, WSLUA_ARG_Struct_values_FORMAT);
|
|
size_t vals = 0;
|
|
defaultoptions(&h);
|
|
while (*fmt) {
|
|
int opt = *fmt++;
|
|
/* we use a size != 0 to mean it is a value */
|
|
size_t size = optsize(L, opt, &fmt);
|
|
/* but some will be zero and not be a value, or vice-versa */
|
|
switch (opt) {
|
|
case 's': case 'c':
|
|
/* these are values */
|
|
size = 1;
|
|
break;
|
|
case 'x': case 'X':
|
|
/* these are not */
|
|
size = 0;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
if (!g_ascii_isalnum(opt))
|
|
controloptions(L, opt, &fmt, &h);
|
|
else if (size && !h.noassign)
|
|
vals++;
|
|
}
|
|
lua_pushinteger(L, vals);
|
|
WSLUA_RETURN(1); /* The number of values */
|
|
}
|
|
|
|
WSLUA_CONSTRUCTOR Struct_tohex (lua_State *L) {
|
|
/* Converts the passed-in binary string to a hex-ascii string. */
|
|
#define WSLUA_ARG_Struct_tohex_BYTESTRING 1 /* A Lua string consisting of binary bytes */
|
|
#define WSLUA_OPTARG_Struct_tohex_LOWERCASE 2 /* True to use lower-case hex characters (default=false). */
|
|
#define WSLUA_OPTARG_Struct_tohex_SEPARATOR 3 /* A string separator to insert between hex bytes (default=nil). */
|
|
const gchar* s = NULL;
|
|
size_t len = 0;
|
|
gboolean lowercase = FALSE;
|
|
const gchar* sep = NULL;
|
|
|
|
/* luaL_checklstring coerces the argument to a string, and that's ok for tohex,
|
|
just not fromhex. In fact, we should accept/coerce a Int64/UInt64 here too someday. */
|
|
s = luaL_checklstring(L, WSLUA_ARG_Struct_tohex_BYTESTRING, &len);
|
|
|
|
lowercase = wslua_optbool(L,WSLUA_OPTARG_Struct_tohex_LOWERCASE,FALSE);
|
|
sep = luaL_optstring(L,WSLUA_OPTARG_Struct_tohex_SEPARATOR,NULL);
|
|
|
|
wslua_bin2hex(L, s, (guint)len, lowercase, sep);
|
|
WSLUA_RETURN(1); /* The Lua hex-ascii string */
|
|
}
|
|
|
|
WSLUA_CONSTRUCTOR Struct_fromhex (lua_State *L) {
|
|
/* Converts the passed-in hex-ascii string to a binary string. */
|
|
#define WSLUA_ARG_Struct_fromhex_HEXBYTES 1 /* A string consisting of hexadecimal bytes like "00 B1 A2" or "1a2b3c4d" */
|
|
#define WSLUA_OPTARG_Struct_fromhex_SEPARATOR 2 /* A string separator between hex bytes/words (default none). */
|
|
const gchar* s = NULL;
|
|
size_t len = 0;
|
|
const gchar* sep = NULL;
|
|
|
|
/* luaL_checklstring coerces the argument to a string, and we don't want to do that */
|
|
s = wslua_checklstring_only(L, WSLUA_ARG_Struct_fromhex_HEXBYTES, &len);
|
|
|
|
sep = luaL_optstring(L,WSLUA_OPTARG_Struct_fromhex_SEPARATOR,NULL);
|
|
|
|
wslua_hex2bin(L, s, (guint)len, sep);
|
|
WSLUA_RETURN(1); /* The Lua binary string */
|
|
}
|
|
|
|
/* }====================================================== */
|
|
|
|
/* Gets registered as metamethod automatically by WSLUA_REGISTER_CLASS/META */
|
|
static int Struct__gc(lua_State* L _U_) {
|
|
return 0;
|
|
}
|
|
|
|
WSLUA_METHODS Struct_methods[] = {
|
|
WSLUA_CLASS_FNREG(Struct,pack),
|
|
WSLUA_CLASS_FNREG(Struct,unpack),
|
|
WSLUA_CLASS_FNREG(Struct,size),
|
|
WSLUA_CLASS_FNREG(Struct,values),
|
|
WSLUA_CLASS_FNREG(Struct,tohex),
|
|
WSLUA_CLASS_FNREG(Struct,fromhex),
|
|
{ NULL, NULL }
|
|
};
|
|
|
|
WSLUA_META Struct_meta[] = {
|
|
{ NULL, NULL }
|
|
};
|
|
|
|
LUALIB_API int Struct_register(lua_State* L) {
|
|
WSLUA_REGISTER_CLASS(Struct);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Editor modelines - http://www.wireshark.org/tools/modelines.html
|
|
*
|
|
* Local Variables:
|
|
* c-basic-offset: 2
|
|
* tab-width: 8
|
|
* indent-tabs-mode: nil
|
|
* End:
|
|
*
|
|
* vi: set shiftwidth=2 tabstop=8 expandtab:
|
|
* :indentSize=2:tabSize=8:noTabs=true:
|
|
*/
|