From c68b92d9dab2976bcee4e695be459a0a3d0577e1 Mon Sep 17 00:00:00 2001 From: "Eric S. Raymond" Date: Wed, 7 Jun 2017 00:05:03 -0400 Subject: [PATCH] More magic-number elimination, and some information hiding. --- advent.h | 2 +- compile.c | 12 ++++++++---- misc.c | 37 ++++++++++++++++++++----------------- 3 files changed, 29 insertions(+), 22 deletions(-) diff --git a/advent.h b/advent.h index 3e5dc9a..47548b6 100644 --- a/advent.h +++ b/advent.h @@ -10,7 +10,7 @@ typedef struct lcg_state unsigned long a, c, m, x; } lcg_state; -typedef long token_t; /* word token - someday this will be a character array */ +typedef long token_t; /* word token - someday this will be char[TOKLEN+1] */ typedef long vocab_t; /* index into a vocabulary array */ struct game_t { diff --git a/compile.c b/compile.c index f8b1167..b6b038e 100644 --- a/compile.c +++ b/compile.c @@ -8,6 +8,8 @@ #define VRBSIZ 35 #define HNTSIZ 20 #define TRVSIZ 885 +#define TOKLEN 5 +#define HINTLEN 5 #include #include @@ -55,7 +57,7 @@ long ATAB[TABSIZ + 1]; long PLAC[NOBJECTS+1]; long FIXD[NOBJECTS+1]; long ACTSPK[VRBSIZ + 1]; -long HINTS[HNTSIZ + 1][5]; +long HINTS[HNTSIZ + 1][HINTLEN]; bool is_set(long, long); long GETTXT(long, long, long); @@ -73,7 +75,7 @@ void read_hints(FILE*); void read_sound_text(FILE*); void write_0d(FILE*, FILE*, long, char*); void write_1d(FILE*, FILE*, long[], long, char*); -void write_hints(FILE*, FILE*, long[][5], long, long, char*); +void write_hints(FILE*, FILE*, long[][HINTLEN], long, long, char*); void write_files(FILE*, FILE*); bool is_set(long var, long position) @@ -105,7 +107,7 @@ long GETTXT(long SKIP,long ONEWRD, long UPPER) { } TEXT=0; - for (int I=1; I<=5; I++) { + for (int I=1; I<=TOKLEN; I++) { TEXT=TEXT*64; if(LNPOSN > LNLENG || (ONEWRD && INLINE[LNPOSN] == 0)) continue; @@ -527,7 +529,7 @@ void write_1d(FILE* c_file, FILE* header_file, long array[], long dim, char* var fprintf(header_file, "extern long %s[%ld];\n", varname, dim); } -void write_hints(FILE* c_file, FILE* header_file, long matrix[][5], long dim1, long dim2, char* varname) +void write_hints(FILE* c_file, FILE* header_file, long matrix[][HINTLEN], long dim1, long dim2, char* varname) { fprintf(c_file, "long %s[][%ld] = {\n", varname, dim2); for (int i = 0; i < dim1; ++i) @@ -556,6 +558,8 @@ void write_files(FILE* c_file, FILE* header_file) fprintf(header_file, "#define VRBSIZ 35\n"); fprintf(header_file, "#define HNTSIZ 20\n"); fprintf(header_file, "#define TRVSIZ 885\n"); + fprintf(header_file, "#define TOKLEN %d\n", TOKLEN); + fprintf(header_file, "#define HINTLEN %d\n", HINTLEN); fprintf(header_file, "\n"); // include the header in the C file diff --git a/misc.c b/misc.c index 5c71c74..6b61790 100644 --- a/misc.c +++ b/misc.c @@ -245,7 +245,7 @@ long GETTXT(bool SKIP,bool ONEWRD, bool UPPER) { } TEXT=0; - for (int I=1; I<=5; I++) { + for (int I=1; I<=TOKLEN; I++) { TEXT=TEXT*64; if(LNPOSN > LNLENG || (ONEWRD && INLINE[LNPOSN] == 0)) continue; @@ -275,12 +275,13 @@ long GETTXT(bool SKIP,bool ONEWRD, bool UPPER) { token_t MAKEWD(long LETTRS) { long I, L, WORD; -/* Combine five uppercase letters (represented by pairs of decimal digits - * in lettrs) to form a 30-bit value matching the one that GETTXT would - * return given those characters plus trailing blanks. Caution: - * lettrs will overflow 31 bits if 5-letter word starts with V-Z. As a - * kludgey workaround, you can increment a letter by 5 by adding 50 to - * the next pair of digits. */ +/* Combine TOKLEN (currently 5) uppercase letters (represented by + * pairs of decimal digits in lettrs) to form a 30-bit value matching + * the one that GETTXT would return given those characters plus + * trailing blanks. Caution: lettrs will overflow 31 bits if + * 5-letter word starts with V-Z. As a kludgey workaround, you can + * increment a letter by 5 by adding 50 to the next pair of + * digits. */ WORD=0; I=1; @@ -299,15 +300,17 @@ long I, L, WORD; void fPUTTXT(token_t WORD, long *sTATE, long CASE) { long ALPH1, ALPH2, BYTE, DIV, I, W; -/* Unpack the 30-bit value in word to obtain up to 5 integer-encoded chars, - * and store them in inline starting at LNPOSN. If LNLENG>=LNPOSN, shift - * existing characters to the right to make room. STATE will be zero when - * puttxt is called with the first of a sequence of words, but is thereafter - * unchanged by the caller, so PUTTXT can use it to maintain state across - * calls. LNPOSN and LNLENG are incremented by the number of chars stored. - * If CASE=1, all letters are made uppercase; if -1, lowercase; if 0, as is. - * any other value for case is the same as 0 but also causes trailing blanks - * to be included (in anticipation of subsequent additional text). */ +/* Unpack the 30-bit value in word to obtain up to TOKLEN (currently + * 5) integer-encoded chars, and store them in inline starting at + * LNPOSN. If LNLENG>=LNPOSN, shift existing characters to the right + * to make room. STATE will be zero when puttxt is called with the + * first of a sequence of words, but is thereafter unchanged by the + * caller, so PUTTXT can use it to maintain state across calls. + * LNPOSN and LNLENG are incremented by the number of chars stored. + * If CASE=1, all letters are made uppercase; if -1, lowercase; if 0, + * as is. any other value for case is the same as 0 but also causes + * trailing blanks to be included (in anticipation of subsequent + * additional text). */ ALPH1=13*CASE+24; @@ -316,7 +319,7 @@ long ALPH1, ALPH2, BYTE, DIV, I, W; /* ALPH1&2 DEFINE RANGE OF WRONG-CASE CHARS, 11-36 OR 37-62 OR EMPTY. */ DIV=64L*64L*64L*64L; W=WORD; - /* 18 */ for (I=1; I<=5; I++) { + /* 18 */ for (I=1; I<=TOKLEN; I++) { if(W <= 0 && STATE == 0 && labs(CASE) <= 1)return; BYTE=W/DIV; if(STATE != 0 || BYTE != 63) goto L12; -- 2.31.1