mirror of
https://git.code.sf.net/p/fldigi/flmsg
synced 2026-08-13 17:30:58 -04:00
d0cd678b40
* Added escape encoding for all file types
- Allows compressed files to transferred using either
base64, base128 or base256 with escaped control bytes.
* Added ability to transmit generic files including:
- jpeg image
- png images
- xls, doc and other office documents
* Transfer time computed for various levels of compression /
base encoding
67 lines
1.5 KiB
C++
67 lines
1.5 KiB
C++
// =====================================================================
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//
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// crc16.h ... crc16 checksum
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//
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// Author: Dave Freese, W1HKJ
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// Copyright: 2010
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//
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// This software 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. It is
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// copyright under the GNU General Public License.
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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 the program; if not, write to the Free Software
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// Foundation, Inc.
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// 59 Temple Place, Suite 330
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// Boston, MA 02111-1307 USA
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//
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// =====================================================================
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#ifndef _CCRC16_
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#define _CCRC16_
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#include <string>
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#include "debug.h"
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using namespace std;
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class Ccrc16 {
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private:
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unsigned int crcval;
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char ss[5];
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public:
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Ccrc16() { crcval = 0xFFFF; }
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~Ccrc16() {};
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void reset() { crcval = 0xFFFF;}
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unsigned int val() {return crcval;}
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string sval() {
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sprintf(ss,"%04X", crcval);
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return ss;
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}
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void update(char c) {
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crcval ^= c;
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for (int i = 0; i < 8; ++i) {
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if (crcval & 1)
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crcval = (crcval >> 1) ^ 0xA001;
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else
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crcval = (crcval >> 1);
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}
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}
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unsigned int crc16(char c) {
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update(c);
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return crcval;
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}
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unsigned int crc16(string s) {
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reset();
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for (size_t i = 0; i < s.length(); i++)
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update((char)(s[i] & 0xFF)); // only use lower half of unicode
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return crcval;
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}
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string scrc16(string s) {
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crc16(s);
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return sval();
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}
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};
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#endif
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