58 |
stackitem *head; /* Head of the stack */ |
stackitem *head; /* Head of the stack */ |
59 |
hashtbl symbols; /* Hash table of all variable bindings */ |
hashtbl symbols; /* Hash table of all variable bindings */ |
60 |
int err; /* Error flag */ |
int err; /* Error flag */ |
|
int non_eval_flag; |
|
61 |
char *in_string; /* Input pending to be read */ |
char *in_string; /* Input pending to be read */ |
62 |
|
char *free_string; /* Free this string when all input is |
63 |
|
read from in_string */ |
64 |
} environment; |
} environment; |
65 |
|
|
66 |
/* A type for pointers to external functions */ |
/* A type for pointers to external functions */ |
74 |
|
|
75 |
env->in_string= NULL; |
env->in_string= NULL; |
76 |
env->err= 0; |
env->err= 0; |
|
env->non_eval_flag= 0; |
|
77 |
for(i= 0; i<HASHTBLSIZE; i++) |
for(i= 0; i<HASHTBLSIZE; i++) |
78 |
env->symbols[i]= NULL; |
env->symbols[i]= NULL; |
79 |
} |
} |
100 |
free(item); /* free the stackitem */ |
free(item); /* free the stackitem */ |
101 |
item=temp; /* go to next stackitem */ |
item=temp; /* go to next stackitem */ |
102 |
} |
} |
|
free(val); /* Free the actual list value */ |
|
103 |
break; |
break; |
104 |
case integer: |
case integer: |
105 |
case func: |
case func: |
106 |
case symb: |
case symb: |
107 |
break; |
break; |
108 |
} |
} |
109 |
|
if(val->id!=NULL) |
110 |
|
free(val->id); |
111 |
|
free(val); /* Free the actual list value */ |
112 |
} |
} |
113 |
} |
} |
114 |
|
|
174 |
|
|
175 |
new_value->content.val= in_val; |
new_value->content.val= in_val; |
176 |
new_value->type= integer; |
new_value->type= integer; |
177 |
new_value->refcount=1; |
new_value->refcount= 1; |
178 |
|
new_value->id= NULL; |
179 |
|
|
180 |
push_val(env, new_value); |
push_val(env, new_value); |
181 |
} |
} |
188 |
new_value->content.ptr= malloc(strlen(in_string)+1); |
new_value->content.ptr= malloc(strlen(in_string)+1); |
189 |
strcpy(new_value->content.ptr, in_string); |
strcpy(new_value->content.ptr, in_string); |
190 |
new_value->type= string; |
new_value->type= string; |
191 |
new_value->refcount=1; |
new_value->refcount= 1; |
192 |
|
new_value->id= NULL; |
193 |
|
|
194 |
push_val(env, new_value); |
push_val(env, new_value); |
195 |
} |
} |
215 |
} |
} |
216 |
|
|
217 |
extern void mangle(environment *env){ |
extern void mangle(environment *env){ |
|
value *new_value; |
|
218 |
char *new_string; |
char *new_string; |
219 |
|
|
220 |
if((env->head)==NULL) { |
if((env->head)==NULL) { |
234 |
toss(env); |
toss(env); |
235 |
if(env->err) return; |
if(env->err) return; |
236 |
|
|
237 |
new_value= malloc(sizeof(value)); |
push_cstring(env, new_string); |
|
new_value->content.ptr= new_string; |
|
|
new_value->type= string; |
|
|
new_value->refcount=1; |
|
|
|
|
|
push_val(env, new_value); |
|
238 |
} |
} |
239 |
|
|
240 |
/* Push a symbol onto the stack. */ |
/* Push a symbol onto the stack. */ |
336 |
} |
} |
337 |
|
|
338 |
/* Prints the top element of the stack. */ |
/* Prints the top element of the stack. */ |
339 |
void print_h(stackitem *stack_head) |
void print_h(stackitem *stack_head, int noquote) |
340 |
{ |
{ |
341 |
switch(stack_head->item->type) { |
switch(stack_head->item->type) { |
342 |
case integer: |
case integer: |
343 |
printf("%d", stack_head->item->content.val); |
printf("%d", stack_head->item->content.val); |
344 |
break; |
break; |
345 |
case string: |
case string: |
346 |
printf("%s", (char*)stack_head->item->content.ptr); |
if(noquote) |
347 |
|
printf("%s", (char*)stack_head->item->content.ptr); |
348 |
|
else |
349 |
|
printf("\"%s\"", (char*)stack_head->item->content.ptr); |
350 |
break; |
break; |
351 |
case symb: |
case symb: |
352 |
printf("%s", ((symbol *)(stack_head->item->content.ptr))->id); |
printf("%s", ((symbol *)(stack_head->item->content.ptr))->id); |
359 |
stack_head=(stackitem *)(stack_head->item->content.ptr); |
stack_head=(stackitem *)(stack_head->item->content.ptr); |
360 |
printf("[ "); |
printf("[ "); |
361 |
while(stack_head != NULL) { |
while(stack_head != NULL) { |
362 |
print_h(stack_head); |
print_h(stack_head, noquote); |
363 |
printf(" "); |
printf(" "); |
364 |
stack_head=stack_head->next; |
stack_head=stack_head->next; |
365 |
} |
} |
374 |
env->err=1; |
env->err=1; |
375 |
return; |
return; |
376 |
} |
} |
377 |
print_h(env->head); |
print_h(env->head, 0); |
378 |
|
nl(); |
379 |
} |
} |
380 |
|
|
381 |
/* Prints the top element of the stack and then discards it. */ |
/* Prints the top element of the stack and then discards it. */ |
386 |
toss(env); |
toss(env); |
387 |
} |
} |
388 |
|
|
389 |
|
extern void princ_(environment *env) { |
390 |
|
if(env->head==NULL) { |
391 |
|
printerr("Too Few Arguments"); |
392 |
|
env->err=1; |
393 |
|
return; |
394 |
|
} |
395 |
|
print_h(env->head, 1); |
396 |
|
} |
397 |
|
|
398 |
|
/* Prints the top element of the stack and then discards it. */ |
399 |
|
extern void princ(environment *env) |
400 |
|
{ |
401 |
|
princ_(env); |
402 |
|
if(env->err) return; |
403 |
|
toss(env); |
404 |
|
} |
405 |
|
|
406 |
/* Only to be called by function printstack. */ |
/* Only to be called by function printstack. */ |
407 |
void print_st(stackitem *stack_head, long counter) |
void print_st(stackitem *stack_head, long counter) |
408 |
{ |
{ |
409 |
if(stack_head->next != NULL) |
if(stack_head->next != NULL) |
410 |
print_st(stack_head->next, counter+1); |
print_st(stack_head->next, counter+1); |
411 |
printf("%ld: ", counter); |
printf("%ld: ", counter); |
412 |
print_h(stack_head); |
print_h(stack_head, 0); |
413 |
nl(); |
nl(); |
414 |
} |
} |
415 |
|
|
417 |
extern void printstack(environment *env) |
extern void printstack(environment *env) |
418 |
{ |
{ |
419 |
if(env->head == NULL) { |
if(env->head == NULL) { |
420 |
|
printf("Stack Empty\n"); |
421 |
return; |
return; |
422 |
} |
} |
423 |
print_st(env->head, 1); |
print_st(env->head, 1); |
|
nl(); |
|
424 |
} |
} |
425 |
|
|
426 |
/* Swap the two top elements on the stack. */ |
/* Swap the two top elements on the stack. */ |
493 |
value* temp_val; |
value* temp_val; |
494 |
stackitem* iterator; |
stackitem* iterator; |
495 |
|
|
496 |
|
eval_start: |
497 |
|
|
498 |
if(env->head==NULL) { |
if(env->head==NULL) { |
499 |
printerr("Too Few Arguments"); |
printerr("Too Few Arguments"); |
500 |
env->err=1; |
env->err=1; |
501 |
return; |
return; |
502 |
} |
} |
503 |
|
|
|
eval_start: |
|
|
|
|
504 |
switch(env->head->item->type) { |
switch(env->head->item->type) { |
505 |
/* if it's a symbol */ |
/* if it's a symbol */ |
506 |
case symb: |
case symb: |
735 |
toss(env); toss(env); |
toss(env); toss(env); |
736 |
} |
} |
737 |
|
|
738 |
|
extern void clear(environment *); |
739 |
|
void forget_sym(symbol **); |
740 |
|
|
741 |
/* Quit stack. */ |
/* Quit stack. */ |
742 |
extern void quit(environment *env) |
extern void quit(environment *env) |
743 |
{ |
{ |
744 |
|
long i; |
745 |
|
|
746 |
|
clear(env); |
747 |
|
if (env->err) return; |
748 |
|
for(i= 0; i<HASHTBLSIZE; i++) { |
749 |
|
while(env->symbols[i]!= NULL) { |
750 |
|
forget_sym(&(env->symbols[i])); |
751 |
|
} |
752 |
|
env->symbols[i]= NULL; |
753 |
|
} |
754 |
exit(EXIT_SUCCESS); |
exit(EXIT_SUCCESS); |
755 |
} |
} |
756 |
|
|
776 |
} |
} |
777 |
} |
} |
778 |
|
|
779 |
|
/* Internal forget function */ |
780 |
|
void forget_sym(symbol **hash_entry) { |
781 |
|
symbol *temp; |
782 |
|
|
783 |
|
temp= *hash_entry; |
784 |
|
*hash_entry= (*hash_entry)->next; |
785 |
|
|
786 |
|
if(temp->val!=NULL) { |
787 |
|
free_val(temp->val); |
788 |
|
} |
789 |
|
free(temp->id); |
790 |
|
free(temp); |
791 |
|
} |
792 |
|
|
793 |
/* Forgets a symbol (remove it from the hash table) */ |
/* Forgets a symbol (remove it from the hash table) */ |
794 |
extern void forget(environment *env) |
extern void forget(environment *env) |
795 |
{ |
{ |
796 |
char* sym_id; |
char* sym_id; |
797 |
stackitem *stack_head= env->head; |
stackitem *stack_head= env->head; |
|
symbol **hash_entry, *temp; |
|
798 |
|
|
799 |
if(stack_head==NULL) { |
if(stack_head==NULL) { |
800 |
printerr("Too Few Arguments"); |
printerr("Too Few Arguments"); |
811 |
sym_id= ((symbol*)(stack_head->item->content.ptr))->id; |
sym_id= ((symbol*)(stack_head->item->content.ptr))->id; |
812 |
toss(env); |
toss(env); |
813 |
|
|
814 |
hash_entry= hash(env->symbols, sym_id); |
return forget_sym(hash(env->symbols, sym_id)); |
|
temp= *hash_entry; |
|
|
*hash_entry= (*hash_entry)->next; |
|
|
|
|
|
if(temp->val!=NULL) { |
|
|
free_val(temp->val); |
|
|
} |
|
|
free(temp->id); |
|
|
free(temp); |
|
815 |
} |
} |
816 |
|
|
817 |
/* Returns the current error number to the stack */ |
/* Returns the current error number to the stack */ |
828 |
init_env(&myenv); |
init_env(&myenv); |
829 |
|
|
830 |
while(1) { |
while(1) { |
831 |
if(myenv.in_string==NULL) |
if(myenv.in_string==NULL) { |
832 |
|
nl(); |
833 |
printstack(&myenv); |
printstack(&myenv); |
834 |
|
printf("> "); |
835 |
|
} |
836 |
read(&myenv); |
read(&myenv); |
837 |
if(myenv.err) { |
if(myenv.err) { |
838 |
printf("(error %d) ", myenv.err); |
printf("(error %d) ", myenv.err); |
1216 |
|
|
1217 |
/* Read a value and place on stack */ |
/* Read a value and place on stack */ |
1218 |
extern void read(environment *env) { |
extern void read(environment *env) { |
1219 |
const char symbform[]= "%[a-zA-Z0-9!$%*+./:<=>?@^_~-]%[\001-\377]"; |
const char symbform[]= "%[a-zA-Z0-9!$%*+./:<=>?@^_~-]%n"; |
1220 |
const char strform[]= "\"%[^\"]\"%[\001-\377]"; |
const char strform[]= "\"%[^\"]\"%n"; |
1221 |
const char intform[]= "%i%[\001-\377]"; |
const char intform[]= "%i%n"; |
1222 |
const char blankform[]= "%*[ \t]%[\001-\377]"; |
const char blankform[]= "%*[ \t]%n"; |
1223 |
const char ebrackform[]= "%*1[]]%[\001-\377]"; |
const char ebrackform[]= "%*1[]]%n"; |
1224 |
const char semicform[]= "%*1[;]%[\001-\377]"; |
const char semicform[]= "%*1[;]%n"; |
1225 |
const char bbrackform[]= "%*1[[]%[\001-\377]"; |
const char bbrackform[]= "%*1[[]%n"; |
1226 |
|
|
1227 |
int itemp; |
int itemp, readlength= -1; |
1228 |
static int depth= 0; |
static int depth= 0; |
1229 |
char *rest, *match; |
char *rest, *match; |
1230 |
size_t inlength; |
size_t inlength; |
1231 |
|
|
1232 |
if(env->in_string==NULL) { |
if(env->in_string==NULL) { |
1233 |
|
if(depth > 0) { |
1234 |
|
printf("]> "); |
1235 |
|
} |
1236 |
readline(env); if(env->err) return; |
readline(env); if(env->err) return; |
1237 |
|
|
1238 |
env->in_string= malloc(strlen(env->head->item->content.ptr)+1); |
env->in_string= malloc(strlen(env->head->item->content.ptr)+1); |
1239 |
|
env->free_string= env->in_string; /* Save the original pointer */ |
1240 |
strcpy(env->in_string, env->head->item->content.ptr); |
strcpy(env->in_string, env->head->item->content.ptr); |
1241 |
toss(env); if(env->err) return; |
toss(env); if(env->err) return; |
1242 |
} |
} |
1245 |
match= malloc(inlength); |
match= malloc(inlength); |
1246 |
rest= malloc(inlength); |
rest= malloc(inlength); |
1247 |
|
|
1248 |
if(sscanf(env->in_string, blankform, rest)) { |
if(sscanf(env->in_string, blankform, &readlength)!=EOF |
1249 |
|
&& readlength != -1) { |
1250 |
; |
; |
1251 |
} else if(sscanf(env->in_string, intform, &itemp, rest) > 0) { |
} else if(sscanf(env->in_string, intform, &itemp, &readlength) != EOF |
1252 |
|
&& readlength != -1) { |
1253 |
push_int(env, itemp); |
push_int(env, itemp); |
1254 |
} else if(sscanf(env->in_string, strform, match, rest) > 0) { |
} else if(sscanf(env->in_string, strform, match, &readlength) != EOF |
1255 |
|
&& readlength != -1) { |
1256 |
push_cstring(env, match); |
push_cstring(env, match); |
1257 |
} else if(sscanf(env->in_string, symbform, match, rest) > 0) { |
} else if(sscanf(env->in_string, symbform, match, &readlength) != EOF |
1258 |
|
&& readlength != -1) { |
1259 |
push_sym(env, match); |
push_sym(env, match); |
1260 |
} else if(sscanf(env->in_string, ebrackform, rest) > 0) { |
} else if(sscanf(env->in_string, ebrackform, &readlength) != EOF |
1261 |
|
&& readlength != -1) { |
1262 |
pack(env); if(env->err) return; |
pack(env); if(env->err) return; |
1263 |
if(depth!=0) depth--; |
if(depth != 0) depth--; |
1264 |
} else if(sscanf(env->in_string, semicform, rest) > 0) { |
} else if(sscanf(env->in_string, semicform, &readlength) != EOF |
1265 |
|
&& readlength != -1) { |
1266 |
push_sym(env, ";"); |
push_sym(env, ";"); |
1267 |
} else if(sscanf(env->in_string, bbrackform, rest) > 0) { |
} else if(sscanf(env->in_string, bbrackform, &readlength) != EOF |
1268 |
|
&& readlength != -1) { |
1269 |
push_sym(env, "["); |
push_sym(env, "["); |
1270 |
depth++; |
depth++; |
1271 |
} else { |
} else { |
1272 |
free(rest); |
free(env->free_string); |
1273 |
rest= NULL; |
env->in_string = env->free_string = NULL; |
1274 |
|
free(match); |
1275 |
|
} |
1276 |
|
if ( env->in_string != NULL) { |
1277 |
|
env->in_string += readlength; |
1278 |
} |
} |
|
|
|
|
free(env->in_string); |
|
|
free(match); |
|
|
|
|
|
env->in_string= rest; |
|
1279 |
|
|
1280 |
if(depth) |
if(depth) |
1281 |
return read(env); |
return read(env); |