91 lines
1.4 KiB
C
91 lines
1.4 KiB
C
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#include <stdio.h>
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#include <stdlib.h>
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void encode();
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void decode();
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int count = 0;
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void usage(const char* prg) {
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printf("USAGE: %s [-e | -d] < src_file > target_file\n", prg);
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exit(0);
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}
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int main(int argc, char* argv[]) {
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int mode = 0;
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if (argc == 2) {
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if (argv[1][1] == 'd')
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mode = 1;
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if (argv[1][1] == 'e')
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mode = 2;
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}
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else
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usage(argv[0]);
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switch (mode) {
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case 1:
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decode();
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break;
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case 2:
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encode();
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break;
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default:
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usage(argv[0]);
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break;
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}
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}
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void decode() {
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int c;
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int addVal = 0;
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while ((c = getchar()) != EOF) {
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c--;
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if (count <= 7)
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c -= (0x63 << count);
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if (c == 195) {
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addVal = 64;
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// fprintf(stderr, "addval after %i bytes\n", count);
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}
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else {
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c += addVal;
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/* if (addVal)
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fprintf(stderr, "decoding-addval %i %i\n", c, c - addVal);
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else
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fprintf(stderr, "decoding: %i\n", (unsigned char)c);
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*/
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addVal = 0;
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if (c == 0)
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c = '\n';
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putchar(c);
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}
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count++;
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}
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}
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void encode_out(int v) {
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if (count <= 7)
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v += (0x63 << count);
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v++;
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putchar(v);
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}
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void encode() {
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int c;
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count = 0;
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while ((c = getchar()) != EOF) {
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if (c == '\n') {
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c = 0;
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}
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if (c >= 192) {
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int _c = 195;
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encode_out(_c);
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c -= 64;
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encode_out(c);
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}
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else {
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encode_out(c);
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}
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count++;
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}
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}
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