sprog.c

这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易于我们学习和理解

#include <u.h>
#include <libc.h>
#include <bio.h>
#include <ctype.h>
#include "code.h"

/* fig leaves for possibly signed char quantities */
#define ISUPPER(c)	isupper((c)&0xff)
#define ISLOWER(c)	islower((c)&0xff)
#define	ISALPHA(c)	isalpha((c)&0xff)
#define	ISDIGIT(c)	isdigit((c)&0xff)
#define ISVOWEL(c)	voweltab[(c)&0xff]
#define Tolower(c)	(ISUPPER(c)? (c)-'A'+'a': (c))
#define pair(a,b)	(((a)<<8) | (b))
#define DLEV		2
#define DSIZ		40

typedef	long	Bits;
#define	Set(h, f)	((long)(h) & (f))

Bits 	nop(char*, char*, char*, int, int);
Bits 	strip(char*, char*, char*, int, int);
Bits 	ize(char*, char*, char*, int, int);
Bits 	i_to_y(char*, char*, char*, int, int);
Bits 	ily(char*, char*, char*, int, int);
Bits 	subst(char*, char*, char*, int, int);
Bits 	CCe(char*, char*, char*, int, int);
Bits 	tion(char*, char*, char*, int, int);
Bits 	an(char*, char*, char*, int, int);
Bits 	s(char*, char*, char*, int, int);
Bits 	es(char*, char*, char*, int, int);
Bits 	bility(char*, char*, char*, int, int);
Bits 	y_to_e(char*, char*, char*, int, int);
Bits 	VCe(char*, char*, char*, int, int);

Bits 	trypref(char*, char*, int, int);
Bits	tryword(char*, char*, int, int);
Bits 	trysuff(char*, int, int);
Bits	dict(char*, char*);
void	typeprint(Bits);
void	pcomma(char*);

void	ise(void);
int	ordinal(void);
char*	skipv(char*);
int	inun(char*, Bits);
char*	ztos(char*);
void	readdict(char*);

typedef	struct	Ptab	Ptab;
struct	Ptab
{
	char*	s;
	int	flag;
};

typedef	struct	Suftab	Suftab;
struct	Suftab
{
	char	*suf;
	Bits	(*p1)(char*, char*, char*, int, int);
	int	n1;
	char	*d1;
	char	*a1;
	int	flag;
	int	affixable;
	Bits	(*p2)(char*, char*, char*, int, int);
	int	n2;
	char	*d2;
	char	*a2;
};

Suftab	staba[] = {
	{"aibohp",subst,1,"-e+ia","",NOUN, NOUN},
	0
};

Suftab	stabc[] =
{
	{"cai",strip,1,"","+c",N_AFFIX, ADJ|NOUN},
	{"citsi",strip,2,"","+ic",N_AFFIX, ADJ | N_AFFIX | NOUN},
	{"citi",ize,1,"-e+ic","",N_AFFIX, ADJ },
	{"cihparg",i_to_y,1,"-y+ic","",NOUN, ADJ|NOUN },
	{"cipocs",ize,1,"-e+ic","",NOUN, ADJ },
	{"cirtem",i_to_y,1,"-y+ic","",NOUN, ADJ },
	{"cigol",i_to_y,1,"-y+ic","",NOUN, ADJ },
	{"cimono",i_to_y,1,"-y+ic","",NOUN, ADJ },
	{"cibohp",subst,1,"-e+ic","",NOUN, ADJ },
	0
};
Suftab	stabd[] =
{
	{"de",strip,1,"","+d",ED,ADJ |COMP,i_to_y,2,"-y+ied","+ed"},
	{"dooh",ily,4,"-y+ihood","+hood",NOUN | ADV, NOUN},
	0
};
Suftab	stabe[] =
{
	/*
	 * V_affix for comment ->commence->commentment??
	 */
	{"ecna",subst,1,"-t+ce","",ADJ,N_AFFIX|_Y|NOUN|VERB|ACTOR|V_AFFIX},
	{"ecne",subst,1,"-t+ce","",ADJ,N_AFFIX|_Y|NOUN|VERB|ACTOR|V_AFFIX},
	{"elbaif",i_to_y,4,"-y+iable","",V_IRREG,ADJ},
	{"elba",CCe,4,"-e+able","+able",V_AFFIX,ADJ},
	{"evi",subst,0,"-ion+ive","",N_AFFIX | V_AFFIX,NOUN | N_AFFIX| ADJ},
	{"ezi",CCe,3,"-e+ize","+ize",N_AFFIX|ADJ ,V_AFFIX | VERB |ION | COMP},
	{"ekil",strip,4,"","+like",N_AFFIX ,ADJ},
	0
};
Suftab	stabg[] =
{
	{"gniee",strip,3,"","+ing",V_IRREG ,ADJ|NOUN},
	{"gnikam",strip,6,"","+making",NOUN,NOUN},
	{"gnipeek",strip,7,"","+keeping",NOUN,NOUN},
	{"gni",CCe,3,"-e+ing","+ing",V_IRREG ,ADJ|ED|NOUN},
	0
};
Suftab	stabl[] =
{
	{"ladio",strip,2,"","+al",NOUN |ADJ,ADJ},
	{"laci",strip,2,"","+al",NOUN |ADJ,ADJ |NOUN|N_AFFIX},
	{"latnem",strip,2,"","+al",N_AFFIX,ADJ},
	{"lanoi",strip,2,"","+al",N_AFFIX,ADJ|NOUN},
	{"luf",ily,3,"-y+iful","+ful",N_AFFIX,ADJ | NOUN},
	0
};
Suftab	stabm[] =
{
		/* congregational + ism */
	{"msi",CCe,3,"-e+ism","ism",N_AFFIX|ADJ,NOUN},
	{"margo",subst,-1,"-ph+m","",NOUN,NOUN},
	0
};
Suftab	stabn[] =
{
	{"noitacifi",i_to_y,6,"-y+ication","",ION,NOUN | N_AFFIX},
	{"noitazi",ize,4,"-e+ation","",ION,NOUN| N_AFFIX},
	{"noit",tion,3,"-e+ion","+ion",ION,NOUN| N_AFFIX | V_AFFIX |VERB|ACTOR},
	{"naino",an,3,"","+ian",NOUN|PROP_COLLECT,NOUN| N_AFFIX},
	{"namow",strip,5,"","+woman",MAN,PROP_COLLECT|N_AFFIX},
	{"nam",strip,3,"","+man",MAN,PROP_COLLECT | N_AFFIX | VERB},
	{"na",an,1,"","+n",NOUN|PROP_COLLECT,NOUN | N_AFFIX},
	{"nemow",strip,5,"","+women",MAN,PROP_COLLECT},
	{"nem",strip,3,"","+man",MAN,PROP_COLLECT},
	{"nosrep",strip,6,"","+person",MAN,PROP_COLLECT},
	0
};
Suftab	stabp[] =
{
	{"pihs",strip,4,"","+ship",NOUN|PROP_COLLECT,NOUN| N_AFFIX},
	0
};
Suftab	stabr[] =
{
	{"rehparg",subst,1,"-y+er","",ACTOR,NOUN,strip,2,"","+er"},
	{"reyhparg",nop,0,"","",0,NOUN},
	{"reyl",nop,0,"","",0,NOUN},
	{"rekam",strip,5,"","+maker",NOUN,NOUN},
	{"repeek",strip,6,"","+keeper",NOUN,NOUN},
	{"re",strip,1,"","+r",ACTOR,NOUN | N_AFFIX|VERB|ADJ,	i_to_y,2,"-y+ier","+er"},
	{"rota",tion,2,"-e+or","",ION,NOUN| N_AFFIX|_Y},
	{"rotc",tion,2,"","+or",ION,NOUN| N_AFFIX},
	{"rotp",tion,2,"","+or",ION,NOUN| N_AFFIX},
	0
};
Suftab	stabs[] =
{
	{"ssen",ily,4,"-y+iness","+ness",ADJ|ADV,NOUN| N_AFFIX},
	{"ssel",ily,4,"-y+iless","+less",NOUN | PROP_COLLECT,ADJ },
	{"se",s,1,"","+s",NOUN | V_IRREG,DONT_TOUCH ,	es,2,"-y+ies","+es"},
	{"s'",s,2,"","+'s",PROP_COLLECT | NOUN,DONT_TOUCH },
	{"s",s,1,"","+s",NOUN | V_IRREG,DONT_TOUCH  },
	0
};
Suftab	stabt[] =
{
	{"tnem",strip,4,"","+ment",V_AFFIX,NOUN | N_AFFIX | ADJ|VERB},
	{"tse",strip,2,"","+st",EST,DONT_TOUCH,	i_to_y,3,"-y+iest","+est" },
	{"tsigol",i_to_y,2,"-y+ist","",N_AFFIX,NOUN | N_AFFIX},
	{"tsi",CCe,3,"-e+ist","+ist",N_AFFIX|ADJ,NOUN | N_AFFIX|COMP},
	0
};
Suftab	staby[] =
{
	{"ycna",subst,1,"-t+cy","",ADJ | N_AFFIX,NOUN | N_AFFIX},
	{"ycne",subst,1,"-t+cy","",ADJ | N_AFFIX,NOUN | N_AFFIX},
	{"ytilib",bility,5,"-le+ility","",ADJ | V_AFFIX,NOUN | N_AFFIX},
	{"ytisuo",nop,0,"","",NOUN},
	{"ytilb",nop,0,"","",0,NOUN},
	{"yti",CCe,3,"-e+ity","+ity",ADJ ,NOUN | N_AFFIX },
	{"ylb",y_to_e,1,"-e+y","",ADJ,ADV},
	{"ylc",nop,0,"","",0},
	{"ylelb",nop,0,"","",0},
	{"ylelp",nop,0,"","",0},
	{"yl",ily,2,"-y+ily","+ly",ADJ,ADV|COMP},
	{"yrtem",subst,0,"-er+ry","",NOUN,NOUN | N_AFFIX},
	{"y",CCe,1,"-e+y","+y",_Y,ADJ|COMP},
	0
};
Suftab	stabz[] =
{
	0
};
Suftab*	suftab[] =
{
	staba,
	stabz,
	stabc,
	stabd,
	stabe,
	stabz,
	stabg,
	stabz,
	stabz,
	stabz,
	stabz,
	stabl,
	stabm,
	stabn,
	stabz,
	stabp,
	stabz,
	stabr,
	stabs,
	stabt,
	stabz,
	stabz,
	stabz,
	stabz,
	staby,
	stabz,
};

Ptab	ptaba[] =
{
	"anti", 0,
	"auto", 0,
	0
};
Ptab	ptabb[] =
{
	"bio", 0,
	0
};
Ptab	ptabc[] =
{
	"counter", 0,
	0
};
Ptab	ptabd[] =
{
	"dis", 0,
	0
};
Ptab	ptabe[] =
{
	"electro", 0,
	0
};
Ptab	ptabf[] =
{
	"femto", 0,
	0
};
Ptab	ptabg[] =
{
	"geo", 0,
	"giga", 0,
	0
};
Ptab	ptabh[] =
{
	"hyper", 0,
	0
};
Ptab	ptabi[] =
{
	"immuno", 0,
	"im", IN,
	"intra", 0,
	"inter", 0,
	"in", IN,
	"ir", IN,
	"iso", 0,
	0
};
Ptab	ptabj[] =
{
	0
};
Ptab	ptabk[] =
{
	"kilo", 0,
	0
};
Ptab	ptabl[] =
{
	0
};
Ptab	ptabm[] =
{
	"magneto", 0,
	"mega", 0,
	"meta", 0,
	"micro", 0,
	"mid", 0,
	"milli", 0,
	"mini", 0,
	"mis", 0,
	"mono", 0,
	"multi", 0,
	0
};
Ptab	ptabn[] =
{
	"nano", 0,
	"neuro", 0,
	"non", 0,
	0
};
Ptab	ptabo[] =
{
	"out", 0,
	"over", 0,
	0
};
Ptab	ptabp[] =
{
	"para", 0,
	"photo", 0,
	"pico", 0,
	"poly", 0,
	"pre", 0,
	"pseudo", 0,
	"psycho", 0,
	0
};
Ptab	ptabq[] =
{
	"quasi", 0,
	0
};
Ptab	ptabr[] =
{
	"radio", 0,
	"re", 0,
	0
};
Ptab	ptabs[] =
{
	"semi", 0,
	"stereo", 0,
	"sub", 0,
	"super", 0,
	0
};
Ptab	ptabt[] =
{
	"tele", 0,
	"tera", 0,
	"thermo", 0,
	0
};
Ptab	ptabu[] =
{
	"ultra", 0,
	"under", 0,	/*must precede un*/
	"un", IN,
	0
};
Ptab	ptabv[] =
{
	0
};
Ptab	ptabw[] =
{
	0
};
Ptab	ptabx[] =
{
	0
};
Ptab	ptaby[] =
{
	0
};
Ptab	ptabz[] =
{
	0
};

Ptab*	preftab[] =
{
	ptaba,
	ptabb,
	ptabc,
	ptabd,
	ptabe,
	ptabf,
	ptabg,
	ptabh,
	ptabi,
	ptabj,
	ptabk,
	ptabl,
	ptabm,
	ptabn,
	ptabo,
	ptabp,
	ptabq,
	ptabr,
	ptabs,
	ptabt,
	ptabu,
	ptabv,
	ptabw,
	ptabx,
	ptaby,
	ptabz,
};

typedef struct {
	char *mesg;
	enum { NONE, SUFF, PREF} type;
} Deriv;

int	aflag;
int	cflag;
int	fflag;
int	vflag;
int	xflag;
int 	nflag;
char	word[500];
char*	original;
Deriv	emptyderiv;
Deriv	deriv[DSIZ+3];
char	affix[DSIZ*10];	/* 10 is longest affix message */
int	prefcount;
int 	suffcount;
char*	acmeid;
char	space[300000];	/* must be as large as "words"+"space" in pcode run */
Bits	encode[2048];	/* must be as long as "codes" in pcode run */
int	nencode;
char	voweltab[256];
char*	spacep[128*128+1];	/* pointer to words starting with 'xx' */
Biobuf	bin;
Biobuf	bout;

char*	codefile = "/sys/lib/amspell";
char*	brfile = "/sys/lib/brspell";
char*	Usage = "usage";

void
main(int argc, char *argv[])
{
	char *ep, *cp;
	char *dp;
	int j, i, c;
	int low;
	Bits h;

	Binit(&bin, 0, OREAD);
	Binit(&bout, 1, OWRITE);
	for(i=0; c = "aeiouyAEIOUY"[i]; i++)
		voweltab[c] = 1;
	while(argc > 1) {
		if(argv[1][0] != '-')
			break;
		for(i=1; c = argv[1][i]; i++)
		switch(c) {
		default:
			fprint(2, "usage: spell [-bcCvx] [-f file]\n");
			exits(Usage);

		case 'a':
			aflag++;
			continue;

		case 'b':
			ise();
			if(!fflag)
				codefile = brfile;
			continue;

		case 'C':		/* for "correct" */
			vflag++;
		case 'c':		/* for ocr */
			cflag++;
			continue;

		case 'v':
			vflag++;
			continue;

		case 'x':
			xflag++;
			continue;

		case 'f':
			if(argc <= 2) {
				fprint(2, "spell: -f requires another argument\n");
				exits(Usage);
			}
			argv++;
			argc--;
			codefile = argv[1];
			fflag++;
			goto brk;
		}
	brk:
		argv++;
		argc--;
	}
	readdict(codefile);
	if(argc > 1) {
		fprint(2, "usage: spell [-bcCvx] [-f file]\n");
		exits(Usage);
	}
	if(aflag)
		cflag = vflag = 0;

	for(;;) {
		affix[0] = 0;
		original = Brdline(&bin, '\n');
		if(original == 0)
			exits(0);
		original[Blinelen(&bin)-1] = 0;
		low = 0;

		if(aflag) {
			acmeid = original;
			while(*original != ':')
				if(*original++ == 0)
					exits(0);
			while(*++original != ':')
				if(*original == 0)
					exits(0);
			*original++ = 0;
		}
		for(ep=word,dp=original; j = *dp; ep++,dp++) {
			if(ISLOWER(j))
				low++;
			if(ep >= word+sizeof(word)-1)
				break;
			*ep = j;
		}
		*ep = 0;

		if(ISDIGIT(word[0]) && ordinal())
			continue;

		h = 0;
		if(!low && !(h = trypref(ep,".",0,ALL|STOP|DONT_TOUCH)))
			for(cp=original+1,dp=word+1; dp<ep; dp++,cp++)
				*dp = Tolower(*cp);
		if(!h)
		for(;;) {	/* at most twice */
			if(h = trypref(ep,".",0,ALL|STOP|DONT_TOUCH))
				break;
			if(h = trysuff(ep,0,ALL|STOP|DONT_TOUCH))
				break;
			if(!ISUPPER(word[0]))
				break;
			cp = original;
			dp = word;
			while(*dp = *cp++) {
					if(!low)
						*dp = Tolower(*dp);
				dp++;
			}
			word[0] = Tolower(word[0]);
		}

		if(cflag) {
			if(!h || Set(h,STOP))
				print("-");
			else if(!vflag)
				print("+");
			else 
				print("%c",'0' + (suffcount>0) +
				   (prefcount>4? 8: 2*prefcount));
		} else if(!h || Set(h,STOP)) {
			if(aflag)
				Bprint(&bout, "%s:%s\n", acmeid, original);
			else
				Bprint(&bout, "%s\n", original);
		} else if(affix[0] != 0 && affix[0] != '.')
			print("%s\t%s\n", affix, original);
	}
	/* not reached */
}

/*	strip exactly one suffix and do
 *	indicated routine(s), which may recursively
 *	strip suffixes
 */
Bits
trysuff(char* ep, int lev, int flag)
{
	Suftab *t;
	char *cp, *sp;
	Bits h = 0;
	int initchar = ep[-1];

	flag &= ~MONO;
	lev += DLEV;
	if(lev < DSIZ) {
		deriv[lev]  = emptyderiv;
		deriv[lev-1] = emptyderiv;
	}
	if(!ISLOWER(initchar))
		return h;
	for(t=suftab[initchar-'a']; sp=t->suf; t++) {
		cp = ep;
		while(*sp)
			if(*--cp != *sp++)
				goto next;
		for(sp=ep-t->n1; --sp >= word && !ISVOWEL(*sp);)
			;
		if(sp < word)
			continue;
		if(!(t->affixable & flag))
			return 0;
		h = (*t->p1)(ep-t->n1, t->d1, t->a1, lev+1, t->flag|STOP);
		if(!h && t->p2!=0) {
			if(lev < DSIZ) {
				deriv[lev] = emptyderiv;
				deriv[lev+1] = emptyderiv;
			}
			h = (*t->p2)(ep-t->n2, t->d2, t->a2, lev, t->flag|STOP);
		}
		break;
	next:;
	}
	return h;
}

Bits
nop(char* ep, char* d, char* a, int lev, int flag)
{
	USED(ep, d, a, lev, flag);
	return 0;
}

Bits
cstrip(char* ep, char* d, char* a, int lev, int flag)
{
	int temp = ep[0];

	if(ISVOWEL(temp) && ISVOWEL(ep[-1])) {
		switch(pair(ep[-1],ep[0])) {
		case pair('a', 'a'):
		case pair('a', 'e'):
		case pair('a', 'i'):
		case pair('e', 'a'):
		case pair('e', 'e'):
		case pair('e', 'i'):
		case pair('i', 'i'):
		case pair('o', 'a'):
			return 0;
		}
	} else
	if(temp==ep[-1]&&temp==ep[-2])
		return 0;
	return strip(ep,d,a,lev,flag);
}

Bits
strip(char* ep, char* d, char* a, int lev, int flag)
{
	Bits h = trypref(ep, a, lev, flag);

	USED(d);
	if(Set(h,MONO) && ISVOWEL(*ep) && ISVOWEL(ep[-2]))
		h = 0;
	if(h)
		return h;
	if(ISVOWEL(*ep) && !ISVOWEL(ep[-1]) && ep[-1]==ep[-2]) {
		h = trypref(ep-1,a,lev,flag|MONO);
		if(h)
			return h;
	}
	return trysuff(ep,lev,flag);
}

Bits
s(char* ep, char* d, char* a, int lev, int flag)
{