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#include "rc.h"
#include "exec.h"
#include "fns.h"
Var *gvar[NVAR] = { 0 }; /* hash for globals */
int
hash(char *s, int n)
{
int h = 0, i = 1;
while(*s) h+=*s++*i++;
h%=n;
return h<0?h+n:h;
}
#define NKW 30
struct kw{
char *name;
int type;
struct kw *next;
}*kw[NKW];
void
kenter(int type, char *name)
{
int h = hash(name, NKW);
struct kw *p = new(struct kw);
p->type = type;
p->name = name;
p->next = kw[h];
kw[h] = p;
}
void
kinit(void)
{
kenter(FOR, "for");
kenter(IN, "in");
kenter(WHILE, "while");
kenter(IF, "if");
kenter(NOT, "not");
kenter(TWIDDLE, "~");
kenter(BANG, "!");
kenter(SUBSHELL, "@");
kenter(SWITCH, "switch");
kenter(FN, "fn");
}
Tree*
klook(char *name)
{
struct kw *p;
Tree *t = token(name, WORD);
for(p = kw[hash(name, NKW)];p;p = p->next)
if(strcmp(p->name, name)==0){
t->type = p->type;
t->iskw = 1;
break;
}
return t;
}
Var*
gvlook(char *name)
{
int h = hash(name, NVAR);
Var *v;
for(v = gvar[h];v;v = v->next) if(strcmp(v->name, name)==0) return v;
return gvar[h] = newvar(strdup(name), gvar[h]);
}
Var*
vlook(char *name)
{
Var *v;
if(runq)
for(v = runq->local;v;v = v->next)
if(strcmp(v->name, name)==0) return v;
return gvlook(name);
}
void
_setvar(char *name, Word *val, int callfn)
{
struct Var *v = vlook(name);
freewords(v->val);
v->val=val;
v->changed=1;
if(callfn && v->changefn)
v->changefn(v);
}
void
setvar(char *name, Word *val)
{
_setvar(name, val, 1);
}
void
bigpath(Var *v)
{
/* convert $PATH to $path */
char *p, *q;
Word **l, *w;
if(v->val == nil){
_setvar("path", nil, 0);
return;
}
p = v->val->word;
w = nil;
l = &w;
/*
* Doesn't handle escaped colon nonsense.
*/
if(p[0] == 0)
p = nil;
while(p){
q = strchr(p, ':');
if(q)
*q = 0;
*l = newword(p[0] ? p : ".", nil);
l = &(*l)->next;
if(q){
*q = ':';
p = q+1;
}else
p = nil;
}
_setvar("path", w, 0);
}
char*
list2strcolon(Word *words)
{
char *value, *s, *t;
int len = 0;
Word *ap;
for(ap = words;ap;ap = ap->next)
len+=1+strlen(ap->word);
value = emalloc(len+1);
s = value;
for(ap = words;ap;ap = ap->next){
for(t = ap->word;*t;) *s++=*t++;
*s++=':';
}
if(s==value)
*s='\0';
else s[-1]='\0';
return value;
}
void
littlepath(Var *v)
{
/* convert $path to $PATH */
char *p;
Word *w;
p = list2strcolon(v->val);
w = new(Word);
w->word = p;
w->next = nil;
_setvar("PATH", w, 1); /* 1: recompute $path to expose colon problems */
}
void
pathinit(void)
{
Var *v;
v = gvlook("path");
v->changefn = littlepath;
v = gvlook("PATH");
v->changefn = bigpath;
bigpath(v);
}
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