stew

a monorepo of some sort
git clone git://git.nsmpr.xyz/stew.git
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proquint.c (2057B)

      1 #include <u.h>
      2 #include <libc.h>
      3 #include "proquint.h"
      4 
      5 /* Map uints to consonants. */
      6 static char uint2consonant[] = {
      7 	'b', 'd', 'f', 'g',
      8 	'h', 'j', 'k', 'l',
      9 	'm', 'n', 'p', 'r',
     10 	's', 't', 'v', 'z'
     11 };
     12 
     13 /* Map uints to vowels. */
     14 static char uint2vowel[] = {
     15 	'a', 'i', 'o', 'u'
     16 };
     17 
     18 void
     19 uint2quint(char *quint /*output*/, u32int i, int sepChar) {
     20 	/* K&R section 2.9: "Right shifting an unsigned quantity always
     21 	   fills vacated it with zero." */
     22 	u32int j;
     23 
     24 # define APPEND(X) *quint = (X); ++quint
     25 # define MASK_FIRST4 0xF0000000
     26 # define MASK_FIRST2 0xC0000000
     27 # define HANDLE_CONSONANT \
     28 	j = i & MASK_FIRST4; \
     29 	i <<= 4; j >>= 28; \
     30 	APPEND(uint2consonant[j])
     31 
     32 # define HANDLE_VOWEL \
     33 	j = i & MASK_FIRST2; \
     34 	i <<= 2; j >>= 30; \
     35 	APPEND(uint2vowel[j])
     36 
     37 	HANDLE_CONSONANT;
     38 	HANDLE_VOWEL;
     39 	HANDLE_CONSONANT;
     40 	HANDLE_VOWEL;
     41 	HANDLE_CONSONANT;
     42 
     43 	if (sepChar) {
     44 		APPEND(((char) sepChar));
     45 	}
     46 
     47 	HANDLE_CONSONANT;
     48 	HANDLE_VOWEL;
     49 	HANDLE_CONSONANT;
     50 	HANDLE_VOWEL;
     51 	HANDLE_CONSONANT;
     52 
     53 # undef HANDLE_VOWEL
     54 # undef HANDLE_CONSONANT
     55 # undef APPEND
     56 # undef MASK_FIRST2
     57 # undef MASK_FIRST4
     58 }
     59 
     60 u32int
     61 quint2uint(char *quint) {
     62 	u32int res = 0;
     63 	char c;
     64 	for(; (c=*quint); ++quint) {
     65 		switch(c) {
     66 		case 'b': res <<= 4; res +=  0; break;
     67 		case 'd': res <<= 4; res +=  1; break;
     68 		case 'f': res <<= 4; res +=  2; break;
     69 		case 'g': res <<= 4; res +=  3; break;
     70 		case 'h': res <<= 4; res +=  4; break;
     71 		case 'j': res <<= 4; res +=  5; break;
     72 		case 'k': res <<= 4; res +=  6; break;
     73 		case 'l': res <<= 4; res +=  7; break;
     74 		case 'm': res <<= 4; res +=  8; break;
     75 		case 'n': res <<= 4; res +=  9; break;
     76 		case 'p': res <<= 4; res += 10; break;
     77 		case 'r': res <<= 4; res += 11; break;
     78 		case 's': res <<= 4; res += 12; break;
     79 		case 't': res <<= 4; res += 13; break;
     80 		case 'v': res <<= 4; res += 14; break;
     81 		case 'z': res <<= 4; res += 15; break;
     82 		case 'a': res <<= 2; res +=  0; break;
     83 		case 'i': res <<= 2; res +=  1; break;
     84 		case 'o': res <<= 2; res +=  2; break;
     85 		case 'u': res <<= 2; res +=  3; break;
     86 		default: break;
     87 		}
     88 	}
     89 	return res;
     90 }