11 |
|
|
12 |
typedef struct stack_item |
typedef struct stack_item |
13 |
{ |
{ |
14 |
enum {value, string, ref, func, symbol, list} type; |
enum { |
15 |
|
value, /* Integer */ |
16 |
|
string, |
17 |
|
ref, /* Reference (to an element in the hash table) */ |
18 |
|
func, /* Function pointer */ |
19 |
|
symbol, |
20 |
|
list |
21 |
|
} type; /* Tells what kind of stack element */ |
22 |
|
|
23 |
union { |
union { |
24 |
void* ptr; |
void* ptr; /* Pointer to the content */ |
25 |
int val; |
int val; /* ...or an integer */ |
26 |
} content; |
} content; /* Stores a pointer or an integer */ |
27 |
|
|
28 |
char* id; |
char* id; /* Symbol name */ |
29 |
struct stack_item* next; |
struct stack_item* next; /* Next element */ |
30 |
} stackitem; |
} stackitem; |
31 |
|
|
32 |
|
|
33 |
typedef stackitem* hashtbl[HASHTBLSIZE]; |
typedef stackitem* hashtbl[HASHTBLSIZE]; /* Hash table declaration */ |
34 |
typedef void (*funcp)(stackitem**); |
typedef void (*funcp)(stackitem**); /* Function pointer declaration */ |
35 |
|
|
36 |
|
|
37 |
|
/* Initiates a newly created hash table. */ |
38 |
void init_hashtbl(hashtbl out_hash) |
void init_hashtbl(hashtbl out_hash) |
39 |
{ |
{ |
40 |
long i; |
long i; |
43 |
out_hash[i]= NULL; |
out_hash[i]= NULL; |
44 |
} |
} |
45 |
|
|
46 |
|
/* Returns a pointer to an element in the hash table. */ |
47 |
stackitem** hash(hashtbl in_hashtbl, const char* in_string) |
stackitem** hash(hashtbl in_hashtbl, const char* in_string) |
48 |
{ |
{ |
49 |
long i= 0; |
long i= 0; |
51 |
char key= 0; |
char key= 0; |
52 |
stackitem** position; |
stackitem** position; |
53 |
|
|
54 |
while(1){ |
while(1){ /* Hash in_string */ |
55 |
key= in_string[i++]; |
key= in_string[i++]; |
56 |
if(key=='\0') |
if(key=='\0') |
57 |
break; |
break; |
61 |
out_hash= out_hash%HASHTBLSIZE; |
out_hash= out_hash%HASHTBLSIZE; |
62 |
position= &(in_hashtbl[out_hash]); |
position= &(in_hashtbl[out_hash]); |
63 |
|
|
64 |
while(1){ |
while(1){ /* Return position if empty */ |
65 |
if(*position==NULL) |
if(*position==NULL) |
66 |
return position; |
return position; |
67 |
|
|
68 |
if(strcmp(in_string, (*position)->id)==0) |
if(strcmp(in_string, (*position)->id)==0) /* Return position if match */ |
69 |
return position; |
return position; |
70 |
|
|
71 |
position= &((*position)->next); |
position= &((*position)->next); /* Try next */ |
72 |
} |
} |
73 |
} |
} |
74 |
|
|
75 |
|
/* Generic push function. */ |
76 |
int push(stackitem** stack_head, stackitem* in_item) |
int push(stackitem** stack_head, stackitem* in_item) |
77 |
{ |
{ |
78 |
in_item->next= *stack_head; |
in_item->next= *stack_head; |
80 |
return 1; |
return 1; |
81 |
} |
} |
82 |
|
|
83 |
|
/* Push a value on the stack. */ |
84 |
int push_val(stackitem** stack_head, int in_val) |
int push_val(stackitem** stack_head, int in_val) |
85 |
{ |
{ |
86 |
stackitem* new_item= malloc(sizeof(stackitem)); |
stackitem* new_item= malloc(sizeof(stackitem)); |
91 |
return 1; |
return 1; |
92 |
} |
} |
93 |
|
|
94 |
|
/* Copy a string onto the stack. */ |
95 |
int push_cstring(stackitem** stack_head, const char* in_string) |
int push_cstring(stackitem** stack_head, const char* in_string) |
96 |
{ |
{ |
97 |
stackitem* new_item= malloc(sizeof(stackitem)); |
stackitem* new_item= malloc(sizeof(stackitem)); |
103 |
return 1; |
return 1; |
104 |
} |
} |
105 |
|
|
106 |
|
/* Create a new hash entry. */ |
107 |
int mk_hashentry(hashtbl in_hashtbl, stackitem* in_item, const char* id) |
int mk_hashentry(hashtbl in_hashtbl, stackitem* in_item, const char* id) |
108 |
{ |
{ |
109 |
in_item->id= malloc(strlen(id)+1); |
in_item->id= malloc(strlen(id)+1); |
114 |
return 1; |
return 1; |
115 |
} |
} |
116 |
|
|
117 |
|
/* Define a function a new function in the hash table. */ |
118 |
void def_func(hashtbl in_hashtbl, funcp in_func, const char* id) |
void def_func(hashtbl in_hashtbl, funcp in_func, const char* id) |
119 |
{ |
{ |
120 |
stackitem* temp= malloc(sizeof(stackitem)); |
stackitem* temp= malloc(sizeof(stackitem)); |
125 |
mk_hashentry(in_hashtbl, temp, id); |
mk_hashentry(in_hashtbl, temp, id); |
126 |
} |
} |
127 |
|
|
128 |
|
/* Define a new symbol in the hash table. */ |
129 |
void def_sym(hashtbl in_hashtbl, const char* id) |
void def_sym(hashtbl in_hashtbl, const char* id) |
130 |
{ |
{ |
131 |
stackitem* temp= malloc(sizeof(stackitem)); |
stackitem* temp= malloc(sizeof(stackitem)); |
132 |
|
|
133 |
temp->type= symbol; |
temp->type= symbol; |
|
|
|
134 |
mk_hashentry(in_hashtbl, temp, id); |
mk_hashentry(in_hashtbl, temp, id); |
135 |
} |
} |
136 |
|
|
137 |
|
/* Push a reference to an entry in the hash table onto the stack. */ |
138 |
int push_ref(stackitem** stack_head, hashtbl in_hash, const char* in_string) |
int push_ref(stackitem** stack_head, hashtbl in_hash, const char* in_string) |
139 |
{ |
{ |
140 |
static void* handle= NULL; |
static void* handle= NULL; |
144 |
new_item->content.ptr= *hash(in_hash, in_string); |
new_item->content.ptr= *hash(in_hash, in_string); |
145 |
new_item->type= ref; |
new_item->type= ref; |
146 |
|
|
147 |
if(handle==NULL) |
if(new_item->content.ptr==NULL) { /* If hash entry empty */ |
148 |
handle= dlopen(NULL, RTLD_LAZY); |
if(handle==NULL) /* If no handle */ |
149 |
|
handle= dlopen(NULL, RTLD_LAZY); |
150 |
if(new_item->content.ptr==NULL) { |
|
151 |
symbol= dlsym(handle, in_string); |
symbol= dlsym(handle, in_string); /* Get function pointer */ |
152 |
if(dlerror()==NULL) |
if(dlerror()==NULL) /* If existing function pointer */ |
153 |
def_func(in_hash, symbol, in_string); |
def_func(in_hash, symbol, in_string); /* Store function pointer */ |
154 |
else |
else |
155 |
def_sym(in_hash, in_string); |
def_sym(in_hash, in_string); /* Make symbol */ |
156 |
|
|
157 |
new_item->content.ptr= *hash(in_hash, in_string); |
new_item->content.ptr= *hash(in_hash, in_string); /* XXX */ |
158 |
new_item->type= ref; |
new_item->type= ref; |
159 |
} |
} |
160 |
|
|
162 |
return 1; |
return 1; |
163 |
} |
} |
164 |
|
|
165 |
|
void printerr(const char* in_string) { |
166 |
|
fprintf(stderr, "Err: %s\n", in_string); |
167 |
|
} |
168 |
|
|
169 |
|
/* Discard the top element of the stack. */ |
170 |
extern void toss(stackitem** stack_head) |
extern void toss(stackitem** stack_head) |
171 |
{ |
{ |
172 |
stackitem* temp= *stack_head; |
stackitem* temp= *stack_head; |
173 |
|
|
174 |
if((*stack_head)==NULL) |
if((*stack_head)==NULL) { |
175 |
|
printerr("Stack empty"); |
176 |
return; |
return; |
177 |
|
} |
178 |
|
|
179 |
if((*stack_head)->type==string) |
if((*stack_head)->type==string) |
180 |
free((*stack_head)->content.ptr); |
free((*stack_head)->content.ptr); |
183 |
free(temp); |
free(temp); |
184 |
} |
} |
185 |
|
|
186 |
|
/* Print newline. */ |
187 |
|
extern void nl() |
188 |
|
{ |
189 |
|
printf("\n"); |
190 |
|
} |
191 |
|
|
192 |
/* print_stack(stack); */ |
/* Prints the top element of the stack. */ |
193 |
void print_st(stackitem* stack_head, long counter) |
void print_(stackitem** stack_head) |
194 |
{ |
{ |
195 |
if(stack_head->next != NULL) |
if((*stack_head)==NULL) { |
196 |
print_st(stack_head->next, counter+1); |
printerr("Stack empty"); |
197 |
|
return; |
198 |
|
} |
199 |
|
|
200 |
switch(stack_head->type){ |
switch((*stack_head)->type) { |
201 |
case value: |
case value: |
202 |
printf("%ld: %d\n", counter, (int)stack_head->content.val); |
printf("%d", (*stack_head)->content.val); |
203 |
break; |
break; |
204 |
case string: |
case string: |
205 |
printf("%ld: \"%s\"\n", counter, (char*)stack_head->content.ptr); |
printf("%s", (char*)(*stack_head)->content.ptr); |
206 |
break; |
break; |
207 |
case ref: |
case ref: |
208 |
printf("%ld: %s\n", counter, ((stackitem*)stack_head->content.ptr)->id); |
printf("%s", ((stackitem*)(*stack_head)->content.ptr)->id); |
209 |
break; |
break; |
|
case func: |
|
210 |
case symbol: |
case symbol: |
211 |
default: |
default: |
212 |
printf("%ld: %p\n", counter, stack_head->content.ptr); |
printf("%p", (*stack_head)->content.ptr); |
213 |
break; |
break; |
214 |
} |
} |
215 |
} |
} |
216 |
|
|
217 |
|
/* Prints the top element of the stack and then discards it. */ |
218 |
|
extern void print(stackitem** stack_head) |
219 |
|
{ |
220 |
|
print_(stack_head); |
221 |
|
toss(stack_head); |
222 |
|
} |
223 |
|
|
224 |
|
/* Only to be called by function printstack. */ |
225 |
|
void print_st(stackitem* stack_head, long counter) |
226 |
|
{ |
227 |
|
if(stack_head->next != NULL) |
228 |
|
print_st(stack_head->next, counter+1); |
229 |
|
|
230 |
|
printf("%ld: ", counter); |
231 |
|
print_(&stack_head); |
232 |
|
nl(); |
233 |
|
} |
234 |
|
|
235 |
|
/* Prints the stack. */ |
236 |
extern void printstack(stackitem** stack_head) |
extern void printstack(stackitem** stack_head) |
237 |
{ |
{ |
238 |
if(*stack_head != NULL) { |
if(*stack_head != NULL) { |
239 |
print_st(*stack_head, 1); |
print_st(*stack_head, 1); |
240 |
printf("\n"); |
printf("\n"); |
241 |
|
} else { |
242 |
|
printerr("Stack empty"); |
243 |
} |
} |
244 |
} |
} |
245 |
|
|
246 |
|
/* If the top element is a reference, determine if it's a reference to a |
247 |
|
function, and if it is, toss the reference and execute the function. */ |
248 |
extern void eval(stackitem** stack_head) |
extern void eval(stackitem** stack_head) |
249 |
{ |
{ |
250 |
funcp in_func; |
funcp in_func; |
251 |
|
|
252 |
if((*stack_head)==NULL || (*stack_head)->type!=ref) |
if((*stack_head)==NULL || (*stack_head)->type!=ref) { |
253 |
|
printerr("Stack empty or not a reference"); |
254 |
return; |
return; |
255 |
|
} |
256 |
|
|
257 |
if(((stackitem*)(*stack_head)->content.ptr)->type==func) { |
if(((stackitem*)(*stack_head)->content.ptr)->type==func) { |
258 |
in_func= (funcp)((stackitem*)(*stack_head)->content.ptr)->content.ptr; |
in_func= (funcp)((stackitem*)(*stack_head)->content.ptr)->content.ptr; |
259 |
toss(stack_head); |
toss(stack_head); |
260 |
(*in_func)(stack_head); |
(*in_func)(stack_head); |
261 |
return; |
return; |
262 |
} |
} else |
263 |
|
printerr("Not a function"); |
264 |
} |
} |
265 |
|
|
266 |
|
/* Parse input. */ |
267 |
int stack_read(stackitem** stack_head, hashtbl in_hash, char* in_line) |
int stack_read(stackitem** stack_head, hashtbl in_hash, char* in_line) |
268 |
{ |
{ |
269 |
char *temp, *rest; |
char *temp, *rest; |
274 |
temp= malloc(inlength); |
temp= malloc(inlength); |
275 |
rest= malloc(inlength); |
rest= malloc(inlength); |
276 |
|
|
277 |
if((convert= sscanf(in_line, "\"%[^\"\n\r]\" %[^\n\r]", temp, rest)) >= 1) |
do { |
278 |
push_cstring(stack_head, temp); |
/* If string */ |
279 |
else if((convert= sscanf(in_line, "%d %[^\n\r]", &itemp, rest)) >= 1) |
if((convert= sscanf(in_line, "\"%[^\"\n\r]\" %[^\n\r]", temp, rest))) { |
280 |
push_val(stack_head, itemp); |
push_cstring(stack_head, temp); |
281 |
else if((convert= sscanf(in_line, "%[^ ;\n\r]%[^\n\r]", temp, rest)) >= 1) |
break; |
282 |
push_ref(stack_head, in_hash, temp); |
} |
283 |
else if((convert= sscanf(in_line, "%c%[^\n\r]", temp, rest)) >= 1) |
/* If value */ |
284 |
if(*temp==';') |
if((convert= sscanf(in_line, "%d %[^\n\r]", &itemp, rest))) { |
285 |
eval(stack_head); |
push_val(stack_head, itemp); |
286 |
|
break; |
287 |
|
} |
288 |
|
/* Escape ';' with '\' */ |
289 |
|
if((convert= sscanf(in_line, "\\%c%[^\n\r]", temp, rest))) { |
290 |
|
temp[1]= '\0'; |
291 |
|
push_ref(stack_head, in_hash, temp); |
292 |
|
break; |
293 |
|
} |
294 |
|
/* If symbol */ |
295 |
|
if((convert= sscanf(in_line, "%[^ ;\n\r]%[^\n\r]", temp, rest))) { |
296 |
|
push_ref(stack_head, in_hash, temp); |
297 |
|
break; |
298 |
|
} |
299 |
|
/* If ';' */ |
300 |
|
if((convert= sscanf(in_line, "%c%[^\n\r]", temp, rest)) && *temp==';') { |
301 |
|
eval(stack_head); /* Evaluate top element */ |
302 |
|
break; |
303 |
|
} |
304 |
|
} while(0); |
305 |
|
|
306 |
|
|
307 |
free(temp); |
free(temp); |
308 |
|
|
317 |
return 1; |
return 1; |
318 |
} |
} |
319 |
|
|
320 |
extern void print(stackitem** stack_head) |
/* Make a list. */ |
|
{ |
|
|
if((*stack_head)==NULL) |
|
|
return; |
|
|
|
|
|
switch((*stack_head)->type){ |
|
|
case value: |
|
|
printf("%d", (*stack_head)->content.val); |
|
|
break; |
|
|
case string: |
|
|
printf("%s", (char*)(*stack_head)->content.ptr); |
|
|
break; |
|
|
case ref: |
|
|
printf("%s", ((stackitem*)(*stack_head)->content.ptr)->id); |
|
|
break; |
|
|
case symbol: |
|
|
default: |
|
|
printf("%p", (*stack_head)->content.ptr); |
|
|
break; |
|
|
} |
|
|
|
|
|
toss(stack_head); |
|
|
} |
|
|
|
|
321 |
extern void pack(stackitem** stack_head) |
extern void pack(stackitem** stack_head) |
322 |
{ |
{ |
323 |
void* delimiter; |
void* delimiter; |
324 |
stackitem *iterator, *temp, *pack; |
stackitem *iterator, *temp, *pack; |
325 |
|
|
326 |
if((*stack_head)==NULL) |
if((*stack_head)==NULL) { |
327 |
|
printerr("Stack empty"); |
328 |
return; |
return; |
329 |
|
} |
330 |
|
|
331 |
delimiter= (*stack_head)->content.ptr; |
delimiter= (*stack_head)->content.ptr; /* Get delimiter */ |
332 |
toss(stack_head); |
toss(stack_head); |
333 |
|
|
334 |
iterator= *stack_head; |
iterator= *stack_head; |
335 |
|
|
336 |
|
/* Search for first delimiter */ |
337 |
while(iterator->next!=NULL && iterator->next->content.ptr!=delimiter) |
while(iterator->next!=NULL && iterator->next->content.ptr!=delimiter) |
338 |
iterator= iterator->next; |
iterator= iterator->next; |
339 |
|
|
340 |
|
/* Extract list */ |
341 |
temp= *stack_head; |
temp= *stack_head; |
342 |
*stack_head= iterator->next; |
*stack_head= iterator->next; |
343 |
iterator->next= NULL; |
iterator->next= NULL; |
345 |
if(*stack_head!=NULL && (*stack_head)->content.ptr==delimiter) |
if(*stack_head!=NULL && (*stack_head)->content.ptr==delimiter) |
346 |
toss(stack_head); |
toss(stack_head); |
347 |
|
|
348 |
|
/* Push list */ |
349 |
pack= malloc(sizeof(stackitem)); |
pack= malloc(sizeof(stackitem)); |
350 |
pack->type= list; |
pack->type= list; |
351 |
pack->content.ptr= temp; |
pack->content.ptr= temp; |
352 |
|
|
353 |
push(stack_head, pack); |
push(stack_head, pack); |
354 |
} |
} |
355 |
|
|
356 |
|
/* Relocate elements of the list on the stack. */ |
357 |
|
extern void expand(stackitem** stack_head) |
358 |
|
{ |
359 |
|
stackitem *temp, *new_head; |
360 |
|
|
361 |
|
/* Is top element a list? */ |
362 |
|
if((*stack_head)==NULL || (*stack_head)->type!=list) { |
363 |
|
printerr("Stack empty or not a list"); |
364 |
|
return; |
365 |
|
} |
366 |
|
|
367 |
|
/* The first list element is the new stack head */ |
368 |
|
new_head= temp= (*stack_head)->content.ptr; |
369 |
|
toss(stack_head); |
370 |
|
|
371 |
|
/* Search the end of the list */ |
372 |
|
while(temp->next!=NULL) |
373 |
|
temp= temp->next; |
374 |
|
|
375 |
|
/* Connect the the tail of the list with the old stack head */ |
376 |
|
temp->next= *stack_head; |
377 |
|
*stack_head= new_head; /* ...and voila! */ |
378 |
|
} |
379 |
|
|
380 |
|
/* Swap the two top elements on the stack. */ |
381 |
|
extern void swap(stackitem** stack_head) |
382 |
|
{ |
383 |
|
stackitem* temp= (*stack_head); |
384 |
|
|
385 |
|
if((*stack_head)==NULL) { |
386 |
|
printerr("Stack empty"); |
387 |
|
return; |
388 |
|
} |
389 |
|
|
390 |
extern void nl() |
if((*stack_head)->next==NULL) |
391 |
|
return; |
392 |
|
|
393 |
|
*stack_head= (*stack_head)->next; |
394 |
|
temp->next= (*stack_head)->next; |
395 |
|
(*stack_head)->next= temp; |
396 |
|
} |
397 |
|
|
398 |
|
/* Compares two elements by reference. */ |
399 |
|
extern void eq(stackitem** stack_head) |
400 |
{ |
{ |
401 |
printf("\n"); |
void *left, *right; |
402 |
|
int result; |
403 |
|
|
404 |
|
if((*stack_head)==NULL || (*stack_head)->next==NULL) { |
405 |
|
printerr("Not enough elements to compare"); |
406 |
|
return; |
407 |
|
} |
408 |
|
|
409 |
|
left= (*stack_head)->content.ptr; |
410 |
|
swap(stack_head); |
411 |
|
right= (*stack_head)->content.ptr; |
412 |
|
result= (left==right); |
413 |
|
|
414 |
|
toss(stack_head); toss(stack_head); |
415 |
|
push_val(stack_head, (left==right)); |
416 |
} |
} |
417 |
|
|
418 |
|
/* Negates the top element on the stack. */ |
419 |
|
extern void not(stackitem** stack_head) |
420 |
|
{ |
421 |
|
int value; |
422 |
|
|
423 |
|
if((*stack_head)==NULL || (*stack_head)->type!=value) { |
424 |
|
printerr("Stack empty or element is not a value"); |
425 |
|
return; |
426 |
|
} |
427 |
|
|
428 |
|
value= (*stack_head)->content.val; |
429 |
|
toss(stack_head); |
430 |
|
push_val(stack_head, !value); |
431 |
|
} |
432 |
|
|
433 |
|
/* Compares the two top elements on the stack and return 0 if they're the |
434 |
|
same. */ |
435 |
|
extern void neq(stackitem** stack_head) |
436 |
|
{ |
437 |
|
eq(stack_head); |
438 |
|
not(stack_head); |
439 |
|
} |
440 |
|
|
441 |
|
/* Give a symbol some content. */ |
442 |
|
extern void def(stackitem** stack_head) |
443 |
|
{ |
444 |
|
stackitem *temp, *value; |
445 |
|
|
446 |
|
if(*stack_head==NULL || (*stack_head)->next==NULL |
447 |
|
|| (*stack_head)->type!=ref) { |
448 |
|
printerr("Define what?"); |
449 |
|
return; |
450 |
|
} |
451 |
|
|
452 |
|
temp= (*stack_head)->content.ptr; |
453 |
|
value= (*stack_head)->next; |
454 |
|
temp->content= value->content; |
455 |
|
value->content.ptr=NULL; |
456 |
|
temp->type= value->type; |
457 |
|
|
458 |
|
toss(stack_head); toss(stack_head); |
459 |
|
} |
460 |
|
|
461 |
|
/* Quit stack. */ |
462 |
extern void quit() |
extern void quit() |
463 |
{ |
{ |
464 |
exit(EXIT_SUCCESS); |
exit(EXIT_SUCCESS); |
479 |
printf("okidok\n "); |
printf("okidok\n "); |
480 |
} |
} |
481 |
|
|
482 |
|
exit(EXIT_SUCCESS); |
|
return EXIT_SUCCESS; |
|
483 |
} |
} |
484 |
|
|
485 |
/* Local Variables: */ |
/* Local Variables: */ |