ref: b9f2c8f2ae01ab8a0a168fd7136e94c2eb8a7b48
parent: 45242db976cf2b63fff70c98b81861ddbcbf5e21
author: Lennart Augustsson <lennart@augustsson.net>
date: Sun Oct 13 13:26:42 EDT 2024
Remove old junk
--- a/bw.c
+++ /dev/null
@@ -1,194 +1,0 @@
-#include <inttypes.h>
-#include <stdlib.h>
-#include <string.h>
-#include <stdio.h>
-
-typedef uint32_t index_t;
-
-/*
- * |.......................................|
- * ^ ^
- * a b
- * <- n ->
- * <- m ->
- * <- o ->
- */
-static uint8_t *compar_arg;
-static size_t compar_len;
-int compar(const void *pa, const void *pb)
-{- index_t a = *(index_t*)pa;
- index_t b = *(index_t*)pb;
- int r;
- if (a == b)
- return 0;
- if (a < b) {- size_t n = compar_len - b; /* bytes until end of buffer */
- r = memcmp(compar_arg + a, compar_arg + b, n);
- if (r)
- return r;
- size_t m = b - a;
- r = memcmp(compar_arg + a + n, compar_arg, m);
- if (r)
- return r;
- size_t o = a;
- return memcmp(compar_arg, compar_arg + m, o);
- } else {- size_t n = compar_len - a; /* bytes until end of buffer */
- r = memcmp(compar_arg + a, compar_arg + b, n);
- if (r)
- return r;
- size_t m = a - b;
- r = memcmp(compar_arg, compar_arg + b + n, m);
- if (r)
- return r;
- size_t o = a;
- return memcmp(compar_arg + m, compar_arg, o);
-
- }
- return 0;
-}
-
-/* Sort all rotations of buf, and the indices of the sorted strings in res. */
-void
-sort_buffer(uint8_t *buf, size_t buflen, index_t *res)
-{- for(size_t i = 0; i < buflen; i++)
- res[i] = i;
- compar_arg = buf;
- compar_len = buflen;
- qsort(res, buflen, sizeof(index_t), compar);
-}
-
-void
-put_rep(FILE *out, size_t n)
-{- if (n > 127)
- put_rep(out, n / 128);
- fputc(n % 128 + 128, out);
-}
-
-#define MINRLE 3
-
-void
-rle(FILE *out, uint8_t *data, size_t len)
-{- for(size_t i = 0; i < len; ) {- uint8_t c = data[i++];
- size_t n;
- for(n = 1; i < len && data[i] == c; i++, n++)
- ;
- if (n >= MINRLE) {- put_rep(out, n - 1);
- fputc(c, out);
- } else {- while(n-- > 0)
- fputc(c, out);
- }
- }
-}
-
-size_t
-get_rep(FILE *in)
-{- size_t n = 0;
- for(;;) {- int c = fgetc(in);
- //fprintf(stderr,"get_rep %02x\n", c);
- if (c < 0) abort();
- if (c < 128) {- ungetc(c, in);
- return n;
- }
- n = n * 128 + c - 128;
- }
-}
-
-void
-unrle(FILE *in, uint8_t *data, size_t len)
-{- for(size_t i = 0; i < len; ) {- size_t n = get_rep(in);
- int c = fgetc(stdin);
- //fprintf(stderr,"unrle %02x\n", c);
- if (c < 0) abort();
- //fprintf(stderr, "n=%d c='%c'\n", (int)n, c);
- n += 1;
- for(size_t j = 0; j < n; j++) {- data[i++] = c;
- }
- //fprintf(stderr, "i=%d\n", (int)i);
- }
-}
-
-#define MAXSIZE 10000000
-
-int
-main(int argc, char **argv)
-{- int encode = argc == 1;
-
- if (encode) {- fprintf(stderr, "encode\n");
- uint8_t *data = malloc(MAXSIZE);
- size_t len = fread(data, 1, MAXSIZE, stdin);
- index_t *res = malloc(len * sizeof(index_t));
-
- sort_buffer((uint8_t*)data, len, res);
-#if 0
- for(size_t i = 0; i < len; i++) {- index_t offs = res[i];
- //fprintf(stderr, "offs=%d\n", (int)offs);
- fwrite(data + offs, 1, len - offs, stdout);
- fwrite(data,1, offs, stdout);
- fputs("\n", stdout);- }
-#endif
- uint8_t *last = malloc(len + 1);
- index_t zero;
- for(size_t i = 0; i < len; i++) {- index_t offs = res[i];
- last[i] = data[(offs + len - 1) % len];
- if (offs == 0)
- zero = i;
- }
- last[len] = 0;
- fprintf(stderr, "len=%d, zero=%d\n", (int)len, (int)zero);
- // fprintf(stderr, "%s\n", last);
- put_rep(stdout, len); fputc(0, stdout);
- put_rep(stdout, zero); fputc(0, stdout);
- rle(stdout, last, len);
- // fwrite(last, 1, len, stdout);
- } else {- fprintf(stderr, "decode\n");
- size_t len = get_rep(stdin); if (fgetc(stdin) != 0) abort();
- size_t zero = get_rep(stdin); if (fgetc(stdin) != 0) abort();
- fprintf(stderr, "len=%d, zero=%d\n", (int)len, (int)zero);
- uint8_t *data = malloc(len);
- unrle(stdin, data, len);
- // fwrite(data, 1, len, stdout);
-#define MAXCHAR 128
- size_t count[MAXCHAR];
- index_t *pred = malloc(len * sizeof(index_t));
- uint8_t *odata = malloc(len);
- for(size_t i = 0; i < MAXCHAR; i++) {- count[i] = 0;
- }
- for(size_t i = 0; i < len; i++) {- pred[i] = count[data[i]]++;
- }
- size_t sum = 0;
- for(size_t i = 0; i < MAXCHAR; i++) {- size_t s = count[i];
- count[i] = sum;
- sum += s;
- }
- size_t i = zero;
- for(size_t j = len; j > 0; j--) {- odata[j - 1] = data[i];
- i = pred[i] + count[data[i]];
- }
- fwrite(odata, 1, len, stdout);
- }
- exit(0);
-}
--
⑨