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 |
|
break; |
107 |
case symb: |
case symb: |
108 |
|
free(((symbol*)(val->content.ptr))->id); |
109 |
|
if(((symbol*)(val->content.ptr))->val!=NULL) |
110 |
|
free_val(((symbol*)(val->content.ptr))->val); |
111 |
|
free(val->content.ptr); |
112 |
break; |
break; |
113 |
} |
} |
114 |
|
free(val); /* Free the actual list value */ |
115 |
} |
} |
116 |
} |
} |
117 |
|
|
160 |
} |
} |
161 |
} |
} |
162 |
|
|
|
/* Generic push function. */ |
|
|
void push(environment *env, stackitem* in_item) |
|
|
{ |
|
|
in_item->next= env->head; |
|
|
env->head= in_item; |
|
|
} |
|
|
|
|
163 |
/* Push a value onto the stack */ |
/* Push a value onto the stack */ |
164 |
void push_val(environment *env, value *val) |
void push_val(environment *env, value *val) |
165 |
{ |
{ |
166 |
stackitem *new_item= malloc(sizeof(stackitem)); |
stackitem *new_item= malloc(sizeof(stackitem)); |
167 |
new_item->item= val; |
new_item->item= val; |
168 |
val->refcount++; |
val->refcount++; |
169 |
push(env, new_item); |
new_item->next= env->head; |
170 |
|
env->head= new_item; |
171 |
} |
} |
172 |
|
|
173 |
/* Push an integer onto the stack. */ |
/* Push an integer onto the stack. */ |
174 |
void push_int(environment *env, int in_val) |
void push_int(environment *env, int in_val) |
175 |
{ |
{ |
176 |
value *new_value= malloc(sizeof(value)); |
value *new_value= malloc(sizeof(value)); |
|
stackitem *new_item= malloc(sizeof(stackitem)); |
|
|
new_item->item= new_value; |
|
177 |
|
|
178 |
new_value->content.val= in_val; |
new_value->content.val= in_val; |
179 |
new_value->type= integer; |
new_value->type= integer; |
180 |
new_value->refcount=1; |
new_value->refcount= 1; |
181 |
|
|
182 |
push(env, new_item); |
push_val(env, new_value); |
183 |
} |
} |
184 |
|
|
185 |
/* Copy a string onto the stack. */ |
/* Copy a string onto the stack. */ |
186 |
void push_cstring(environment *env, const char *in_string) |
void push_cstring(environment *env, const char *in_string) |
187 |
{ |
{ |
188 |
value *new_value= malloc(sizeof(value)); |
value *new_value= malloc(sizeof(value)); |
|
stackitem *new_item= malloc(sizeof(stackitem)); |
|
|
new_item->item=new_value; |
|
189 |
|
|
190 |
new_value->content.ptr= malloc(strlen(in_string)+1); |
new_value->content.ptr= malloc(strlen(in_string)+1); |
191 |
strcpy(new_value->content.ptr, in_string); |
strcpy(new_value->content.ptr, in_string); |
192 |
new_value->type= string; |
new_value->type= string; |
193 |
new_value->refcount=1; |
new_value->refcount= 1; |
194 |
|
|
195 |
push(env, new_item); |
push_val(env, new_value); |
196 |
} |
} |
197 |
|
|
198 |
/* Mangle a symbol name to a valid C identifier name */ |
/* Mangle a symbol name to a valid C identifier name */ |
216 |
} |
} |
217 |
|
|
218 |
extern void mangle(environment *env){ |
extern void mangle(environment *env){ |
|
value *new_value; |
|
219 |
char *new_string; |
char *new_string; |
220 |
|
|
221 |
if((env->head)==NULL) { |
if((env->head)==NULL) { |
235 |
toss(env); |
toss(env); |
236 |
if(env->err) return; |
if(env->err) return; |
237 |
|
|
238 |
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); |
|
239 |
} |
} |
240 |
|
|
241 |
/* Push a symbol onto the stack. */ |
/* Push a symbol onto the stack. */ |
242 |
void push_sym(environment *env, const char *in_string) |
void push_sym(environment *env, const char *in_string) |
243 |
{ |
{ |
|
stackitem *new_item; /* The new stack item */ |
|
|
/* ...which will contain... */ |
|
244 |
value *new_value; /* A new symbol value */ |
value *new_value; /* A new symbol value */ |
245 |
/* ...which might point to... */ |
/* ...which might point to... */ |
246 |
symbol **new_symbol; /* (if needed) A new actual symbol */ |
symbol **new_symbol; /* (if needed) A new actual symbol */ |
253 |
const char *dlerr; /* Dynamic linker error */ |
const char *dlerr; /* Dynamic linker error */ |
254 |
char *mangled; /* Mangled function name */ |
char *mangled; /* Mangled function name */ |
255 |
|
|
|
/* Create a new stack item containing a new value */ |
|
|
new_item= malloc(sizeof(stackitem)); |
|
256 |
new_value= malloc(sizeof(value)); |
new_value= malloc(sizeof(value)); |
|
new_item->item=new_value; |
|
257 |
|
|
258 |
/* The new value is a symbol */ |
/* The new value is a symbol */ |
259 |
new_value->type= symb; |
new_value->type= symb; |
297 |
new_fvalue->refcount= 1; |
new_fvalue->refcount= 1; |
298 |
} |
} |
299 |
} |
} |
300 |
push(env, new_item); |
push_val(env, new_value); |
301 |
} |
} |
302 |
|
|
303 |
/* Print newline. */ |
/* Print newline. */ |
337 |
} |
} |
338 |
|
|
339 |
/* Prints the top element of the stack. */ |
/* Prints the top element of the stack. */ |
340 |
void print_h(stackitem *stack_head) |
void print_h(stackitem *stack_head, int noquote) |
341 |
{ |
{ |
342 |
switch(stack_head->item->type) { |
switch(stack_head->item->type) { |
343 |
case integer: |
case integer: |
344 |
printf("%d", stack_head->item->content.val); |
printf("%d", stack_head->item->content.val); |
345 |
break; |
break; |
346 |
case string: |
case string: |
347 |
printf("%s", (char*)stack_head->item->content.ptr); |
if(noquote) |
348 |
|
printf("%s", (char*)stack_head->item->content.ptr); |
349 |
|
else |
350 |
|
printf("\"%s\"", (char*)stack_head->item->content.ptr); |
351 |
break; |
break; |
352 |
case symb: |
case symb: |
353 |
printf("%s", ((symbol *)(stack_head->item->content.ptr))->id); |
printf("%s", ((symbol *)(stack_head->item->content.ptr))->id); |
360 |
stack_head=(stackitem *)(stack_head->item->content.ptr); |
stack_head=(stackitem *)(stack_head->item->content.ptr); |
361 |
printf("[ "); |
printf("[ "); |
362 |
while(stack_head != NULL) { |
while(stack_head != NULL) { |
363 |
print_h(stack_head); |
print_h(stack_head, noquote); |
364 |
printf(" "); |
printf(" "); |
365 |
stack_head=stack_head->next; |
stack_head=stack_head->next; |
366 |
} |
} |
375 |
env->err=1; |
env->err=1; |
376 |
return; |
return; |
377 |
} |
} |
378 |
print_h(env->head); |
print_h(env->head, 0); |
379 |
|
nl(); |
380 |
} |
} |
381 |
|
|
382 |
/* Prints the top element of the stack and then discards it. */ |
/* Prints the top element of the stack and then discards it. */ |
387 |
toss(env); |
toss(env); |
388 |
} |
} |
389 |
|
|
390 |
|
extern void princ_(environment *env) { |
391 |
|
if(env->head==NULL) { |
392 |
|
printerr("Too Few Arguments"); |
393 |
|
env->err=1; |
394 |
|
return; |
395 |
|
} |
396 |
|
print_h(env->head, 1); |
397 |
|
} |
398 |
|
|
399 |
|
/* Prints the top element of the stack and then discards it. */ |
400 |
|
extern void princ(environment *env) |
401 |
|
{ |
402 |
|
princ_(env); |
403 |
|
if(env->err) return; |
404 |
|
toss(env); |
405 |
|
} |
406 |
|
|
407 |
/* Only to be called by function printstack. */ |
/* Only to be called by function printstack. */ |
408 |
void print_st(stackitem *stack_head, long counter) |
void print_st(stackitem *stack_head, long counter) |
409 |
{ |
{ |
410 |
if(stack_head->next != NULL) |
if(stack_head->next != NULL) |
411 |
print_st(stack_head->next, counter+1); |
print_st(stack_head->next, counter+1); |
412 |
printf("%ld: ", counter); |
printf("%ld: ", counter); |
413 |
print_h(stack_head); |
print_h(stack_head, 0); |
414 |
nl(); |
nl(); |
415 |
} |
} |
416 |
|
|
418 |
extern void printstack(environment *env) |
extern void printstack(environment *env) |
419 |
{ |
{ |
420 |
if(env->head == NULL) { |
if(env->head == NULL) { |
421 |
|
printf("Stack Empty\n"); |
422 |
return; |
return; |
423 |
} |
} |
424 |
print_st(env->head, 1); |
print_st(env->head, 1); |
|
nl(); |
|
425 |
} |
} |
426 |
|
|
427 |
/* Swap the two top elements on the stack. */ |
/* Swap the two top elements on the stack. */ |
494 |
value* temp_val; |
value* temp_val; |
495 |
stackitem* iterator; |
stackitem* iterator; |
496 |
|
|
497 |
|
eval_start: |
498 |
|
|
499 |
if(env->head==NULL) { |
if(env->head==NULL) { |
500 |
printerr("Too Few Arguments"); |
printerr("Too Few Arguments"); |
501 |
env->err=1; |
env->err=1; |
502 |
return; |
return; |
503 |
} |
} |
504 |
|
|
|
eval_start: |
|
|
|
|
505 |
switch(env->head->item->type) { |
switch(env->head->item->type) { |
506 |
/* if it's a symbol */ |
/* if it's a symbol */ |
507 |
case symb: |
case symb: |
579 |
/* Make a list. */ |
/* Make a list. */ |
580 |
extern void pack(environment *env) |
extern void pack(environment *env) |
581 |
{ |
{ |
|
void* delimiter; |
|
582 |
stackitem *iterator, *temp; |
stackitem *iterator, *temp; |
583 |
value *pack; |
value *pack; |
584 |
|
|
|
delimiter= env->head->item->content.ptr; /* Get delimiter */ |
|
|
toss(env); |
|
|
|
|
585 |
iterator= env->head; |
iterator= env->head; |
586 |
|
|
587 |
if(iterator==NULL || iterator->item->content.ptr==delimiter) { |
if(iterator==NULL |
588 |
|
|| (iterator->item->type==symb |
589 |
|
&& ((symbol*)(iterator->item->content.ptr))->id[0]=='[')) { |
590 |
temp= NULL; |
temp= NULL; |
591 |
toss(env); |
toss(env); |
592 |
} else { |
} else { |
593 |
/* Search for first delimiter */ |
/* Search for first delimiter */ |
594 |
while(iterator->next!=NULL |
while(iterator->next!=NULL |
595 |
&& iterator->next->item->content.ptr!=delimiter) |
&& (iterator->next->item->type!=symb |
596 |
|
|| ((symbol*)(iterator->next->item->content.ptr))->id[0]!='[')) |
597 |
iterator= iterator->next; |
iterator= iterator->next; |
598 |
|
|
599 |
/* Extract list */ |
/* Extract list */ |
611 |
pack->content.ptr= temp; |
pack->content.ptr= temp; |
612 |
pack->refcount= 1; |
pack->refcount= 1; |
613 |
|
|
614 |
temp= malloc(sizeof(stackitem)); |
push_val(env, pack); |
|
temp->item= pack; |
|
|
|
|
|
push(env, temp); |
|
615 |
rev(env); |
rev(env); |
616 |
} |
} |
617 |
|
|
736 |
toss(env); toss(env); |
toss(env); toss(env); |
737 |
} |
} |
738 |
|
|
739 |
|
extern void clear(environment *); |
740 |
|
void forget_sym(symbol **); |
741 |
|
|
742 |
/* Quit stack. */ |
/* Quit stack. */ |
743 |
extern void quit(environment *env) |
extern void quit(environment *env) |
744 |
{ |
{ |
745 |
|
long i; |
746 |
|
|
747 |
|
clear(env); |
748 |
|
if (env->err) return; |
749 |
|
for(i= 0; i<HASHTBLSIZE; i++) { |
750 |
|
while(env->symbols[i]!= NULL) { |
751 |
|
forget_sym(&(env->symbols[i])); |
752 |
|
} |
753 |
|
env->symbols[i]= NULL; |
754 |
|
} |
755 |
exit(EXIT_SUCCESS); |
exit(EXIT_SUCCESS); |
756 |
} |
} |
757 |
|
|
777 |
} |
} |
778 |
} |
} |
779 |
|
|
780 |
|
/* Internal forget function */ |
781 |
|
void forget_sym(symbol **hash_entry) { |
782 |
|
symbol *temp; |
783 |
|
|
784 |
|
temp= *hash_entry; |
785 |
|
*hash_entry= (*hash_entry)->next; |
786 |
|
|
787 |
|
if(temp->val!=NULL) { |
788 |
|
free_val(temp->val); |
789 |
|
} |
790 |
|
free(temp->id); |
791 |
|
free(temp); |
792 |
|
} |
793 |
|
|
794 |
/* Forgets a symbol (remove it from the hash table) */ |
/* Forgets a symbol (remove it from the hash table) */ |
795 |
extern void forget(environment *env) |
extern void forget(environment *env) |
796 |
{ |
{ |
797 |
char* sym_id; |
char* sym_id; |
798 |
stackitem *stack_head= env->head; |
stackitem *stack_head= env->head; |
|
symbol **hash_entry, *temp; |
|
799 |
|
|
800 |
if(stack_head==NULL) { |
if(stack_head==NULL) { |
801 |
printerr("Too Few Arguments"); |
printerr("Too Few Arguments"); |
812 |
sym_id= ((symbol*)(stack_head->item->content.ptr))->id; |
sym_id= ((symbol*)(stack_head->item->content.ptr))->id; |
813 |
toss(env); |
toss(env); |
814 |
|
|
815 |
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); |
|
816 |
} |
} |
817 |
|
|
818 |
/* Returns the current error number to the stack */ |
/* Returns the current error number to the stack */ |
829 |
init_env(&myenv); |
init_env(&myenv); |
830 |
|
|
831 |
while(1) { |
while(1) { |
832 |
if(myenv.in_string==NULL) |
if(myenv.in_string==NULL) { |
833 |
|
nl(); |
834 |
printstack(&myenv); |
printstack(&myenv); |
835 |
|
printf("> "); |
836 |
|
} |
837 |
read(&myenv); |
read(&myenv); |
838 |
if(myenv.err) { |
if(myenv.err) { |
839 |
printf("(error %d) ", myenv.err); |
printf("(error %d) ", myenv.err); |
1167 |
/* 'to' */ |
/* 'to' */ |
1168 |
extern void to(environment *env) { |
extern void to(environment *env) { |
1169 |
int i, start, ending; |
int i, start, ending; |
1170 |
|
stackitem *temp_head; |
1171 |
|
value *temp_val; |
1172 |
|
|
1173 |
if((env->head)==NULL || env->head->next==NULL) { |
if((env->head)==NULL || env->head->next==NULL) { |
1174 |
printerr("Too Few Arguments"); |
printerr("Too Few Arguments"); |
1188 |
start= env->head->item->content.val; |
start= env->head->item->content.val; |
1189 |
toss(env); if(env->err) return; |
toss(env); if(env->err) return; |
1190 |
|
|
1191 |
push_sym(env, "["); |
temp_head= env->head; |
1192 |
|
env->head= NULL; |
1193 |
|
|
1194 |
if(ending>=start) { |
if(ending>=start) { |
1195 |
for(i= start; i<=ending; i++) |
for(i= ending; i>=start; i--) |
1196 |
push_int(env, i); |
push_int(env, i); |
1197 |
} else { |
} else { |
1198 |
for(i= start; i>=ending; i--) |
for(i= ending; i<=start; i++) |
1199 |
push_int(env, i); |
push_int(env, i); |
1200 |
} |
} |
1201 |
|
|
1202 |
push_sym(env, "["); |
temp_val= malloc(sizeof(value)); |
1203 |
pack(env); if(env->err) return; |
temp_val->content.ptr= env->head; |
1204 |
|
temp_val->refcount= 1; |
1205 |
|
temp_val->type= list; |
1206 |
|
env->head= temp_head; |
1207 |
|
push_val(env, temp_val); |
1208 |
} |
} |
1209 |
|
|
1210 |
/* Read a string */ |
/* Read a string */ |
1217 |
|
|
1218 |
/* Read a value and place on stack */ |
/* Read a value and place on stack */ |
1219 |
extern void read(environment *env) { |
extern void read(environment *env) { |
1220 |
const char symbform[]= "%[a-zA-Z0-9!$%*+./:<=>?@^_~-]%[\001-\377]"; |
const char symbform[]= "%[a-zA-Z0-9!$%*+./:<=>?@^_~-]%n"; |
1221 |
const char strform[]= "\"%[^\"]\"%[\001-\377]"; |
const char strform[]= "\"%[^\"]\"%n"; |
1222 |
const char intform[]= "%i%[\001-\377]"; |
const char intform[]= "%i%n"; |
1223 |
const char blankform[]= "%*[ \t]%[\001-\377]"; |
const char blankform[]= "%*[ \t]%n"; |
1224 |
const char ebrackform[]= "%*1[]]%[\001-\377]"; |
const char ebrackform[]= "%*1[]]%n"; |
1225 |
const char semicform[]= "%*1[;]%[\001-\377]"; |
const char semicform[]= "%*1[;]%n"; |
1226 |
const char bbrackform[]= "%*1[[]%[\001-\377]"; |
const char bbrackform[]= "%*1[[]%n"; |
1227 |
|
|
1228 |
int itemp; |
int itemp, readlength= -1; |
1229 |
static int depth= 0; |
static int depth= 0; |
1230 |
char *rest, *match; |
char *rest, *match; |
1231 |
size_t inlength; |
size_t inlength; |
1232 |
|
|
1233 |
if(env->in_string==NULL) { |
if(env->in_string==NULL) { |
1234 |
|
if(depth > 0) { |
1235 |
|
printf("]> "); |
1236 |
|
} |
1237 |
readline(env); if(env->err) return; |
readline(env); if(env->err) return; |
1238 |
|
|
1239 |
env->in_string= malloc(strlen(env->head->item->content.ptr)+1); |
env->in_string= malloc(strlen(env->head->item->content.ptr)+1); |
1240 |
|
env->free_string= env->in_string; /* Save the original pointer */ |
1241 |
strcpy(env->in_string, env->head->item->content.ptr); |
strcpy(env->in_string, env->head->item->content.ptr); |
1242 |
toss(env); if(env->err) return; |
toss(env); if(env->err) return; |
1243 |
} |
} |
1246 |
match= malloc(inlength); |
match= malloc(inlength); |
1247 |
rest= malloc(inlength); |
rest= malloc(inlength); |
1248 |
|
|
1249 |
if(sscanf(env->in_string, blankform, rest)) { |
if(sscanf(env->in_string, blankform, &readlength)!=EOF |
1250 |
|
&& readlength != -1) { |
1251 |
; |
; |
1252 |
} else if(sscanf(env->in_string, intform, &itemp, rest) > 0) { |
} else if(sscanf(env->in_string, intform, &itemp, &readlength) != EOF |
1253 |
|
&& readlength != -1) { |
1254 |
push_int(env, itemp); |
push_int(env, itemp); |
1255 |
} else if(sscanf(env->in_string, strform, match, rest) > 0) { |
} else if(sscanf(env->in_string, strform, match, &readlength) != EOF |
1256 |
|
&& readlength != -1) { |
1257 |
push_cstring(env, match); |
push_cstring(env, match); |
1258 |
} else if(sscanf(env->in_string, symbform, match, rest) > 0) { |
} else if(sscanf(env->in_string, symbform, match, &readlength) != EOF |
1259 |
|
&& readlength != -1) { |
1260 |
push_sym(env, match); |
push_sym(env, match); |
1261 |
} else if(sscanf(env->in_string, ebrackform, rest) > 0) { |
} else if(sscanf(env->in_string, ebrackform, &readlength) != EOF |
1262 |
push_sym(env, "["); |
&& readlength != -1) { |
1263 |
pack(env); if(env->err) return; |
pack(env); if(env->err) return; |
1264 |
if(depth!=0) depth--; |
if(depth != 0) depth--; |
1265 |
} else if(sscanf(env->in_string, semicform, rest) > 0) { |
} else if(sscanf(env->in_string, semicform, &readlength) != EOF |
1266 |
|
&& readlength != -1) { |
1267 |
push_sym(env, ";"); |
push_sym(env, ";"); |
1268 |
} else if(sscanf(env->in_string, bbrackform, rest) > 0) { |
} else if(sscanf(env->in_string, bbrackform, &readlength) != EOF |
1269 |
|
&& readlength != -1) { |
1270 |
push_sym(env, "["); |
push_sym(env, "["); |
1271 |
depth++; |
depth++; |
1272 |
} else { |
} else { |
1273 |
free(rest); |
free(env->free_string); |
1274 |
rest= NULL; |
env->in_string = env->free_string = NULL; |
1275 |
|
free(match); |
1276 |
|
} |
1277 |
|
if ( env->in_string != NULL) { |
1278 |
|
env->in_string += readlength; |
1279 |
} |
} |
|
|
|
|
free(env->in_string); |
|
|
free(match); |
|
|
|
|
|
env->in_string= rest; |
|
1280 |
|
|
1281 |
if(depth) |
if(depth) |
1282 |
return read(env); |
return read(env); |