diff options
Diffstat (limited to 'utils/rcsh/var.c')
| -rw-r--r-- | utils/rcsh/var.c | 240 |
1 files changed, 240 insertions, 0 deletions
diff --git a/utils/rcsh/var.c b/utils/rcsh/var.c new file mode 100644 index 00000000..cee8adf5 --- /dev/null +++ b/utils/rcsh/var.c @@ -0,0 +1,240 @@ +#include "rc.h" +#include "y.tab.h" + +extern char **_environ; + +typedef struct Kw Kw; + +#define NKW 30 +#define NVAR 521 + +struct Kw{ + char *name; + int type; + Kw *next; +}; + +void updenvlocal(Var *v); +void addenv(Var *v); + +Kw *kw[NKW]; +Var *gvar[NVAR]; + +int +hash(char *s, int n) +{ + int h=0, i=1; + + while(*s) + h+=*s++*i++; + h%=n; + return h<0?h+n:h; +} + +void +kenter(int type, char *name) +{ + int h=hash(name, NKW); + Kw *p=new(Kw); + p->type=type; + p->name=name; + p->next=kw[h]; + kw[h]=p; +} + +void +vinit(void) +{ + char **env, *name, *val, *p; + int i; + Word *w; + Io *f; + int n; + Var *v; + + env = _environ; + for(i=0; env[i]; free(name), i++) { + name = strdup(env[i]); + p = strchr(name, '='); + if(p == 0 || p == name) + continue; + *p = 0; + val = p+1; + n = strlen(val); + if(n == 0) + continue; + + if(strncmp(name, "fn#", 3)!=0) { + /* variable */ + w = 0; + p = val+n-1; + while(*p) { + if(*p == IWS) + *p-- = 0; + for(; *p && *p != IWS; p--) + ; + w=newword(p+1, w); + } + setvar(name, w); + vlook(name)->changed=0; + } else { + /* function */ + f = opencore(val, n); + execcmds(f); + } + } + v = vlook("path"); + p = getenv("path"); + if(v->val == 0 && p) + v->val = newword(p, 0); +} + + +Tree * +klook(char *name) +{ + 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) +{ + Var *v=vlook(name); + freewords(v->val); + v->val=val; + v->changed=1; +} + +Var * +newvar(char *name, Var *next) +{ + Var *v=new(Var); + v->name=name; + v->val=0; + v->fn=0; + v->changed=0; + v->fnchanged=0; + v->next=next; + return v; +} + + +void +execfinit(void) +{ +} + +void +updenv(void) +{ + Var *v, **h; + + for(h=gvar;h!=&gvar[NVAR];h++) + for(v=*h;v;v=v->next) + addenv(v); + + if(runq) + updenvlocal(runq->local); +} + +static void +envput(char *var, char *val) +{ + int i, n; + char *e; + char buf[256]; + + snprint(buf, sizeof(buf), "%s=%s", var, val); + n = strlen(var); + for(i = 0;;i++){ + e = environ[i]; + if(e == 0) + break; + if(strncmp(e, var, n) == 0){ + free(e); + environ[i] = strdup(buf); + return; + } + } + environ = realloc(environ, (i+2)*sizeof(char*)); + environ[i++] = strdup(buf); + environ[i] = 0; +} + +void +addenv(Var *v) +{ + char buf[100], *p; + Io *f; + Word *w; + int i, n; + + if(v->changed){ + v->changed=0; + p = 0; + n = 0; + if(v->val) { + for(w=v->val; w; w=w->next) { + i = strlen(w->word); + p = realloc(p, n+i+1); + memmove(p+n, w->word, i); + n+=i; + p[n++] = IWS; + } + p[n-1] = 0; + envput(v->name, p); + } else + envput(v->name, ""); + free(p); + } + + if(v->fnchanged){ + v->fnchanged=0; + snprint(buf, sizeof(buf), "fn#%s", v->name); + f = openstr(); + pfmt(f, "fn %s %s\n", v->name, v->fn[v->pc-1].s); + envput(buf, f->strp); + closeio(f); + } +} + +void +updenvlocal(Var *v) +{ + if(v){ + updenvlocal(v->next); + addenv(v); + } +} |