ref: 931ae0cfebeb46892406efc7468636e59f8110a9
dir: /sys/src/cmd/rc/var.c/
#include "rc.h" #include "exec.h" #include "fns.h" 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; } #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* newvar(char *name, var *next) { int n = strlen(name)+1; var *v = emalloc(sizeof(var)+n); memmove(v->name, name, n); v->next = next; v->val = 0; v->fn = 0; v->changed = 0; v->fnchanged = 0; return v; } 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(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; } void freevar(var *v) { freewords(v->val); free(v); }