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Diffstat (limited to 'src/cmd/pic/symtab.c')
-rw-r--r--src/cmd/pic/symtab.c104
1 files changed, 104 insertions, 0 deletions
diff --git a/src/cmd/pic/symtab.c b/src/cmd/pic/symtab.c
new file mode 100644
index 00000000..879075c6
--- /dev/null
+++ b/src/cmd/pic/symtab.c
@@ -0,0 +1,104 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <string.h>
+#include "pic.h"
+#include "y.tab.h"
+
+YYSTYPE getvar(char *s) /* return value of variable s (usually pointer) */
+{
+ struct symtab *p;
+ static YYSTYPE bug;
+
+ p = lookup(s);
+ if (p == NULL) {
+ if (islower(s[0]))
+ ERROR "no such variable as %s", s WARNING;
+ else
+ ERROR "no such place as %s", s WARNING;
+ return(bug);
+ }
+ return(p->s_val);
+}
+
+double getfval(char *s) /* return float value of variable s */
+{
+ YYSTYPE y;
+
+ y = getvar(s);
+ return y.f;
+}
+
+void setfval(char *s, double f) /* set variable s to f */
+{
+ struct symtab *p;
+
+ if ((p = lookup(s)) != NULL)
+ p->s_val.f = f;
+}
+
+struct symtab *makevar(char *s, int t, YYSTYPE v) /* make variable named s in table */
+ /* assumes s is static or from tostring */
+{
+ struct symtab *p;
+
+ for (p = stack[nstack].p_symtab; p != NULL; p = p->s_next)
+ if (strcmp(s, p->s_name) == 0)
+ break;
+ if (p == NULL) { /* it's a new one */
+ p = (struct symtab *) malloc(sizeof(struct symtab));
+ if (p == NULL)
+ ERROR "out of symtab space with %s", s FATAL;
+ p->s_next = stack[nstack].p_symtab;
+ stack[nstack].p_symtab = p; /* stick it at front */
+ }
+ p->s_name = s;
+ p->s_type = t;
+ p->s_val = v;
+ return(p);
+}
+
+struct symtab *lookup(char *s) /* find s in symtab */
+{
+ int i;
+ struct symtab *p;
+
+ for (i = nstack; i >= 0; i--) /* look in each active symtab */
+ for (p = stack[i].p_symtab; p != NULL; p = p->s_next)
+ if (strcmp(s, p->s_name) == 0)
+ return(p);
+ return(NULL);
+}
+
+void freesymtab(struct symtab *p) /* free space used by symtab at p */
+{
+ struct symtab *q;
+
+ for ( ; p != NULL; p = q) {
+ q = p->s_next;
+ free(p->s_name); /* assumes done with tostring */
+ free((char *)p);
+ }
+}
+
+void freedef(char *s) /* free definition for string s */
+{
+ struct symtab *p, *q, *op;
+
+ for (p = op = q = stack[nstack].p_symtab; p != NULL; p = p->s_next) {
+ if (strcmp(s, p->s_name) == 0) { /* got it */
+ if (p->s_type != DEFNAME)
+ break;
+ if (p == op) /* 1st elem */
+ stack[nstack].p_symtab = p->s_next;
+ else
+ q->s_next = p->s_next;
+ free(p->s_name);
+ free(p->s_val.p);
+ free((char *)p);
+ return;
+ }
+ q = p;
+ }
+ /* ERROR "%s is not defined at this point", s WARNING; */
+}