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new input filter : nibble_swap (#62)
* input filters: add -Nibble-Swap filter Simply exchanges upper and lower nibbles of each bytes. This should only be a few opcodes per byte on most CPUs; probably faster than a look-up table (e.g. like the bit-reverse filter).
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‎doc/etc/README.man‎

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@@ -316,6 +316,10 @@ minimum
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The \f[I]minimum\fP filter may be used to insert the minimum data address
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into the data.
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.\" ---------- N ---------------------------------------------------------
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.\" nibble swap
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.TP 8n
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\fB\-Nibble_Swap\fP
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This filter may be used to swap upper and lower nibbles of each byte.
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.\" ---------- O ---------------------------------------------------------
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.TP 8n
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offset

‎doc/man1/srec_input.1‎

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The same as the \fB\-MINimum_Big_Endian\fP filter,
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except the value will be written with the least significant byte first.
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.\" ---------- N ---------------------------------------------------------
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.\" nibble swap
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.TP 8n
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\fB\-Nibble_Swap\fP
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This filter may be used to swap upper and lower nibbles of each byte.
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.\" not
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.TP 8n
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\fB\-NOT\fP

‎srecord/arglex/tool.cc‎

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@@ -159,6 +159,7 @@ srecord::arglex_tool::arglex_tool(int argc, char **argv) :
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{ "-MsBin", token_msbin, },
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{ "-MULTiple", token_multiple, },
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{ "-Needham_Hexadecimal", token_needham_hex, },
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{ "-Nibble_Swap", token_nibble_swap, },
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{ "-NOT", token_not, },
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{ "-Not_AUGment", token_crc16_augment_not },
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{ "-Not_CONSTant", token_constant_not, },

‎srecord/arglex/tool.h‎

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@@ -146,6 +146,7 @@ class arglex_tool:
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token_msbin,
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token_multiple,
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token_needham_hex,
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token_nibble_swap,
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token_not,
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token_offset,
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token_ohio_scientific,

‎srecord/arglex/tool/input.cc‎

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#include <srecord/input/filter/message/fletcher16.h>
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#include <srecord/input/filter/message/fletcher32.h>
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#include <srecord/input/filter/message/gcrypt.h>
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#include <srecord/input/filter/nibble_swap.h>
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#include <srecord/input/filter/not.h>
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#include <srecord/input/filter/offset.h>
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#include <srecord/input/filter/or.h>
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}
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break;
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case token_nibble_swap:
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token_next();
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ifp = input_filter_nibble_swap::create(ifp);
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break;
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case token_not:
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token_next();
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ifp = input_filter_not::create(ifp);

‎srecord/input/filter/nibble_swap.cc‎

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//
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// Copyright (c) 2023 fenugrec
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//
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// srecord filter: exchanges upper and lower nibble of each byte,
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// e.g. "0xA6" => "0x6A"
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//
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// This program is free software; you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published by
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// the Free Software Foundation; either version 3 of the License, or (at
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// your option) any later version.
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//
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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// General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with this program. If not, see <http://www.gnu.org/licenses/>.
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//
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#include <srecord/input/filter/nibble_swap.h>
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#include <srecord/record.h>
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srecord::input_filter_nibble_swap::input_filter_nibble_swap(
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const srecord::input::pointer &arg
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) :
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srecord::input_filter(arg)
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{
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}
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srecord::input::pointer
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srecord::input_filter_nibble_swap::create(const input::pointer &a_deeper)
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{
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return pointer(new srecord::input_filter_nibble_swap(a_deeper));
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}
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bool
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srecord::input_filter_nibble_swap::read(srecord::record &record)
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{
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if (!srecord::input_filter::read(record))
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return false;
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if (record.get_type() == srecord::record::type_data)
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{
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for (size_t j = 0; j < record.get_length(); ++j) {
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uint8_t tmp = record.get_data(j);
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record.set_data(j, ((tmp & 0x0F) << 4) | ((tmp & 0xF0) >> 4));
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}
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}
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return true;
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}

‎srecord/input/filter/nibble_swap.h‎

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//
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// Copyright (c) 2023 fenugrec
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//
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// srecord filter: exchanges upper and lower nibble of each byte,
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// e.g. "0xA6" => "0x6A"
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//
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// This program is free software; you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published by
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// the Free Software Foundation; either version 3 of the License, or (at
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// your option) any later version.
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//
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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// General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with this program. If not, see <http://www.gnu.org/licenses/>.
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//
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#ifndef SRECORD_INPUT_FILTER_NIBBLE_SWAP_H
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#define SRECORD_INPUT_FILTER_NIBBLE_SWAP_H
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#include <srecord/input/filter.h>
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namespace srecord {
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/**
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* The srecord::input_filter_nibble_swap class is used to represent the
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* input state of a filter which swaps upper/lower nibbles of each byte.
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*/
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class input_filter_nibble_swap:
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public input_filter
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{
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public:
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/**
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* The destructor.
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*/
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~input_filter_nibble_swap() override = default;
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private:
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/**
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* The constructor.
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*
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* @param deeper
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* The deeper input to be used as a data source.
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*/
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input_filter_nibble_swap(const input::pointer &deeper);
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public:
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/**
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* The create class method is used to create new dynamically
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* allocated instances of this class.
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*
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* @param deeper
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* The incoming data source to be filtered
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*/
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static pointer create(const input::pointer &deeper);
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protected:
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// See base class for documentation.
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bool read(record &record) override;
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public:
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/**
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* The default constructor.
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*/
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input_filter_nibble_swap() = delete;
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/**
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* The copy constructor.
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*/
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input_filter_nibble_swap(const input_filter_nibble_swap &) = delete;
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/**
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* The assignment operator.
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*/
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input_filter_nibble_swap &operator= \
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(const input_filter_nibble_swap &) = delete;
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};
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};
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#endif

‎srecord/srecord.h‎

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#include <srecord/input/filter/message/fletcher16.h>
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#include <srecord/input/filter/message/fletcher32.h>
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#include <srecord/input/filter/message/gcrypt.h>
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#include <srecord/input/filter/nibble_swap.h>
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#include <srecord/input/filter/not.h>
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#include <srecord/input/filter/offset.h>
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#include <srecord/input/filter/or.h>

‎test/02/t0269a.sh‎

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#!/bin/sh
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#
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# srecord - manipulate eprom load files
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# Copyright (C) 2023 fenugrec
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 3 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program. If not, see
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# <http://www.gnu.org/licenses/>.
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#
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TEST_SUBJECT="nibble swap filter"
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. test_prelude.sh
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cat > test.in << 'fubar'
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S00600004844521B
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S1070000F08008552B
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S5030001FB
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fubar
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if test $? -ne 0; then no_result; fi
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cat > test.ok << 'fubar'
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S00600004844521B
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S10700000F0880550C
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S5030001FB
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fubar
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if test $? -ne 0; then no_result; fi
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srec_cat test.in -ns -o test.out
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if test $? -ne 0; then fail; fi
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diff test.ok test.out
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if test $? -ne 0; then fail; fi
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#
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# The things tested here, worked.
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# No other guarantees are made.
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#
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pass

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