1 #include "rc.h"
2 #include "exec.h"
3 #include "fns.h"
4 int hash(char *s, int n)
5 {
6 	register int h=0, i=1;
7 	while(*s) h+=*s++*i++;
8 	h%=n;
9 	return h<0?h+n:h;
10 }
11 #define	NKW	30
12 struct kw{
13 	char *name;
14 	int type;
15 	struct kw *next;
16 }*kw[NKW];
17 void kenter(int type, char *name)
18 {
19 	register int h=hash(name, NKW);
20 	register struct kw *p=new(struct kw);
21 	p->type=type;
22 	p->name=name;
23 	p->next=kw[h];
24 	kw[h]=p;
25 }
26 void kinit(void){
27 	kenter(FOR, "for");
28 	kenter(IN, "in");
29 	kenter(WHILE, "while");
30 	kenter(IF, "if");
31 	kenter(NOT, "not");
32 	kenter(TWIDDLE, "~");
33 	kenter(BANG, "!");
34 	kenter(SUBSHELL, "@");
35 	kenter(SWITCH, "switch");
36 	kenter(FN, "fn");
37 }
38 tree *klook(char *name)
39 {
40 	struct kw *p;
41 	tree *t=token(name, WORD);
42 	for(p=kw[hash(name, NKW)];p;p=p->next)
43 		if(strcmp(p->name, name)==0){
44 			t->type=p->type;
45 			t->iskw=1;
46 			break;
47 		}
48 	return t;
49 }
50 var *gvlook(char *name)
51 {
52 	int h=hash(name, NVAR);
53 	var *v;
54 	for(v=gvar[h];v;v=v->next) if(strcmp(v->name, name)==0) return v;
55 	return gvar[h]=newvar(strdup(name), gvar[h]);
56 }
57 var *vlook(char *name)
58 {
59 	var *v;
60 	if(runq)
61 		for(v=runq->local;v;v=v->next)
62 			if(strcmp(v->name, name)==0) return v;
63 	return gvlook(name);
64 }
65 void _setvar(char *name, word *val, int callfn)
66 {
67 	register struct var *v=vlook(name);
68 	freewords(v->val);
69 	v->val=val;
70 	v->changed=1;
71 	if(callfn && v->changefn)
72 		v->changefn(v);
73 }
74 void setvar(char *name, word *val)
75 {
76 	_setvar(name, val, 1);
77 }
78 void bigpath(var *v)
79 {
80 	/* convert $PATH to $path */
81 	char *p, *q;
82 	word **l, *w;
83 
84 	if(v->val == nil){
85 		_setvar("path", nil, 0);
86 		return;
87 	}
88 	p = v->val->word;
89 	w = nil;
90 	l = &w;
91 	/*
92 	 * Doesn't handle escaped colon nonsense.
93 	 */
94 	if(p[0] == 0)
95 		p = nil;
96 	while(p){
97 		q = strchr(p, ':');
98 		if(q)
99 			*q = 0;
100 		*l = newword(p[0] ? p : ".", nil);
101 		l = &(*l)->next;
102 		if(q){
103 			*q = ':';
104 			p = q+1;
105 		}else
106 			p = nil;
107 	}
108 	_setvar("path", w, 0);
109 }
110 void littlepath(var *v)
111 {
112 	/* convert $path to $PATH */
113 	char *p;
114 	word *w;
115 
116 	p = _list2str(v->val, ':');
117 	w = new(word);
118 	w->word = p;
119 	w->next = nil;
120 	_setvar("PATH", w, 1);	/* 1: recompute $path to expose colon problems */
121 }
122 void pathinit(void)
123 {
124 	var *v;
125 
126 	v = gvlook("path");
127 	v->changefn = littlepath;
128 	v = gvlook("PATH");
129 	v->changefn = bigpath;
130 	bigpath(v);
131 }