11 |
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|
12 |
typedef struct stack_item |
typedef struct stack_item |
13 |
{ |
{ |
14 |
enum {value, string, ref, func} type; |
enum { |
15 |
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value, /* Integer */ |
16 |
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string, |
17 |
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ref, /* Reference (to an element in the hash table) */ |
18 |
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func, /* Function pointer */ |
19 |
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symbol, |
20 |
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list |
21 |
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} type; /* Tells what kind of stack element */ |
22 |
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|
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 |
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|
28 |
char* id; |
char* id; /* Symbol name */ |
29 |
struct stack_item* next; |
struct stack_item* next; /* Next element */ |
30 |
} stackitem; |
} stackitem; |
31 |
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32 |
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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 |
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36 |
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37 |
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/* 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 |
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|
46 |
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/* 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 |
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|
64 |
while(1){ |
while(1){ /* Return position if empty */ |
65 |
if(*position==NULL) |
if(*position==NULL) |
66 |
return position; |
return position; |
67 |
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|
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 |
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|
71 |
position= &((*position)->next); |
position= &((*position)->next); /* Try next */ |
72 |
} |
} |
73 |
} |
} |
74 |
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|
75 |
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/* 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 |
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|
83 |
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/* 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 |
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|
94 |
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/* 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 |
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|
106 |
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/* 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 |
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|
117 |
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/* 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 |
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|
128 |
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/* Define a new symbol in the hash table. */ |
129 |
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void def_sym(hashtbl in_hashtbl, const char* id) |
130 |
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{ |
131 |
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stackitem* temp= malloc(sizeof(stackitem)); |
132 |
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133 |
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temp->type= symbol; |
134 |
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mk_hashentry(in_hashtbl, temp, id); |
135 |
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} |
136 |
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137 |
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/* 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 |
void* handle; |
static void* handle= NULL; |
141 |
void* symbol; |
void* symbol; |
142 |
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|
143 |
stackitem* new_item= malloc(sizeof(stackitem)); |
stackitem* new_item= malloc(sizeof(stackitem)); |
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 |
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|
147 |
if(new_item->content.ptr==NULL) { |
if(new_item->content.ptr==NULL) { /* If hash entry empty */ |
148 |
handle= dlopen(NULL, RTLD_LAZY); |
if(handle==NULL) /* If no handle */ |
149 |
symbol= dlsym(handle, in_string); |
handle= dlopen(NULL, RTLD_LAZY); |
150 |
if(dlerror()==NULL) { |
|
151 |
def_func(in_hash, symbol, in_string); |
symbol= dlsym(handle, in_string); /* Get function pointer */ |
152 |
new_item->content.ptr= *hash(in_hash, in_string); |
if(dlerror()==NULL) /* If existing function pointer */ |
153 |
new_item->type= ref; |
def_func(in_hash, symbol, in_string); /* Store function pointer */ |
154 |
} |
else |
155 |
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def_sym(in_hash, in_string); /* Make symbol */ |
156 |
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|
157 |
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new_item->content.ptr= *hash(in_hash, in_string); /* XXX */ |
158 |
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new_item->type= ref; |
159 |
} |
} |
160 |
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|
161 |
push(stack_head, new_item); |
push(stack_head, new_item); |
162 |
return 1; |
return 1; |
163 |
} |
} |
164 |
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|
165 |
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/* Discard the top element of the stack. */ |
166 |
extern void toss(stackitem** stack_head) |
extern void toss(stackitem** stack_head) |
167 |
{ |
{ |
168 |
stackitem* temp= *stack_head; |
stackitem* temp= *stack_head; |
169 |
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|
170 |
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if((*stack_head)==NULL) |
171 |
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return; |
172 |
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|
173 |
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if((*stack_head)->type==string) |
174 |
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free((*stack_head)->content.ptr); |
175 |
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|
176 |
*stack_head= (*stack_head)->next; |
*stack_head= (*stack_head)->next; |
177 |
free(temp); |
free(temp); |
178 |
} |
} |
179 |
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|
180 |
|
/* Print newline. */ |
181 |
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extern void nl() |
182 |
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{ |
183 |
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printf("\n"); |
184 |
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} |
185 |
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|
186 |
/* print_stack(stack); */ |
/* Prints the top element of the stack. */ |
187 |
void print_st(stackitem* stack_head, long counter) |
void print_(stackitem** stack_head) |
188 |
{ |
{ |
189 |
if(stack_head->next != NULL) |
if((*stack_head)==NULL) |
190 |
print_st(stack_head->next, counter+1); |
return; |
191 |
|
|
192 |
switch(stack_head->type){ |
switch((*stack_head)->type) { |
193 |
case value: |
case value: |
194 |
printf("%ld: %d\n", counter, (int)stack_head->content.val); |
printf("%d", (*stack_head)->content.val); |
195 |
break; |
break; |
196 |
case string: |
case string: |
197 |
printf("%ld: \"%s\"\n", counter, (char*)stack_head->content.ptr); |
printf("%s", (char*)(*stack_head)->content.ptr); |
198 |
break; |
break; |
199 |
case ref: |
case ref: |
200 |
case func: |
printf("%s", ((stackitem*)(*stack_head)->content.ptr)->id); |
201 |
printf("%ld: %p\n", counter, stack_head->content.ptr); |
break; |
202 |
|
case symbol: |
203 |
|
default: |
204 |
|
printf("%p", (*stack_head)->content.ptr); |
205 |
break; |
break; |
206 |
} |
} |
207 |
} |
} |
208 |
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|
209 |
|
/* Prints the top element of the stack and then discards it. */ |
210 |
|
extern void print(stackitem** stack_head) |
211 |
|
{ |
212 |
|
print_(stack_head); |
213 |
|
toss(stack_head); |
214 |
|
} |
215 |
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|
216 |
|
/* Only to be called by function printstack. */ |
217 |
|
void print_st(stackitem* stack_head, long counter) |
218 |
|
{ |
219 |
|
if(stack_head->next != NULL) |
220 |
|
print_st(stack_head->next, counter+1); |
221 |
|
|
222 |
|
printf("%ld: ", counter); |
223 |
|
print_(&stack_head); |
224 |
|
nl(); |
225 |
|
} |
226 |
|
|
227 |
|
/* Prints the stack. */ |
228 |
extern void printstack(stackitem** stack_head) |
extern void printstack(stackitem** stack_head) |
229 |
{ |
{ |
230 |
if(*stack_head != NULL) { |
if(*stack_head != NULL) { |
233 |
} |
} |
234 |
} |
} |
235 |
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|
236 |
|
/* If the top element is a reference, determine if it's a reference to a |
237 |
|
function, and if it is, toss the reference and execute the function. */ |
238 |
extern void eval(stackitem** stack_head) |
extern void eval(stackitem** stack_head) |
239 |
{ |
{ |
240 |
funcp in_func; |
funcp in_func; |
250 |
} |
} |
251 |
} |
} |
252 |
|
|
253 |
|
/* Parse input. */ |
254 |
int stack_read(stackitem** stack_head, hashtbl in_hash, char* in_line) |
int stack_read(stackitem** stack_head, hashtbl in_hash, char* in_line) |
255 |
{ |
{ |
256 |
char *temp, *rest; |
char *temp, *rest; |
261 |
temp= malloc(inlength); |
temp= malloc(inlength); |
262 |
rest= malloc(inlength); |
rest= malloc(inlength); |
263 |
|
|
264 |
if((convert= sscanf(in_line, "\"%[^\"\n\r]\" %[^\n\r]", temp, rest)) >= 1) |
do { |
265 |
push_cstring(stack_head, temp); |
/* If string */ |
266 |
else if((convert= sscanf(in_line, "%d %[^\n\r]", &itemp, rest)) >= 1) |
if((convert= sscanf(in_line, "\"%[^\"\n\r]\" %[^\n\r]", temp, rest))) { |
267 |
push_val(stack_head, itemp); |
push_cstring(stack_head, temp); |
268 |
else if((convert= sscanf(in_line, "%[^ ;\n\r]%[^\n\r]", temp, rest)) >= 1) |
break; |
269 |
push_ref(stack_head, in_hash, temp); |
} |
270 |
else if((convert= sscanf(in_line, "%c%[^\n\r]", temp, rest)) >= 1) |
/* If value */ |
271 |
if(*temp==';') |
if((convert= sscanf(in_line, "%d %[^\n\r]", &itemp, rest))) { |
272 |
eval(stack_head); |
push_val(stack_head, itemp); |
273 |
|
break; |
274 |
|
} |
275 |
|
/* Escape ';' with '\' */ |
276 |
|
if((convert= sscanf(in_line, "\\%c%[^\n\r]", temp, rest))) { |
277 |
|
temp[1]= '\0'; |
278 |
|
push_ref(stack_head, in_hash, temp); |
279 |
|
break; |
280 |
|
} |
281 |
|
/* If symbol */ |
282 |
|
if((convert= sscanf(in_line, "%[^ ;\n\r]%[^\n\r]", temp, rest))) { |
283 |
|
push_ref(stack_head, in_hash, temp); |
284 |
|
break; |
285 |
|
} |
286 |
|
/* If ';' */ |
287 |
|
if((convert= sscanf(in_line, "%c%[^\n\r]", temp, rest)) && *temp==';') { |
288 |
|
eval(stack_head); /* Evaluate top element */ |
289 |
|
break; |
290 |
|
} |
291 |
|
} while(0); |
292 |
|
|
293 |
|
|
294 |
free(temp); |
free(temp); |
295 |
|
|
304 |
return 1; |
return 1; |
305 |
} |
} |
306 |
|
|
307 |
extern void print(stackitem** stack_head) |
/* Make a list. */ |
308 |
|
extern void pack(stackitem** stack_head) |
309 |
{ |
{ |
310 |
if((*stack_head)==NULL) |
void* delimiter; |
311 |
|
stackitem *iterator, *temp, *pack; |
312 |
|
|
313 |
|
if((*stack_head)==NULL) /* No delimiter */ |
314 |
return; |
return; |
315 |
|
|
316 |
if((*stack_head)->type==value) |
delimiter= (*stack_head)->content.ptr; /* Get delimiter */ |
317 |
printf("%d", (*stack_head)->content.val); |
toss(stack_head); |
318 |
else if((*stack_head)->type==string) |
|
319 |
printf("%s", (char*)(*stack_head)->content.ptr); |
iterator= *stack_head; |
320 |
else |
|
321 |
printf("%p", (*stack_head)->content.ptr); |
/* Search for first delimiter */ |
322 |
|
while(iterator->next!=NULL && iterator->next->content.ptr!=delimiter) |
323 |
|
iterator= iterator->next; |
324 |
|
|
325 |
|
/* Extract list */ |
326 |
|
temp= *stack_head; |
327 |
|
*stack_head= iterator->next; |
328 |
|
iterator->next= NULL; |
329 |
|
|
330 |
|
if(*stack_head!=NULL && (*stack_head)->content.ptr==delimiter) |
331 |
|
toss(stack_head); |
332 |
|
|
333 |
|
/* Push list */ |
334 |
|
pack= malloc(sizeof(stackitem)); |
335 |
|
pack->type= list; |
336 |
|
pack->content.ptr= temp; |
337 |
|
|
338 |
|
push(stack_head, pack); |
339 |
|
} |
340 |
|
|
341 |
|
/* Relocate elements of the list on the stack. */ |
342 |
|
extern void expand(stackitem** stack_head) |
343 |
|
{ |
344 |
|
stackitem *temp, *new_head; |
345 |
|
|
346 |
|
/* Is top element a list? */ |
347 |
|
if((*stack_head)==NULL || (*stack_head)->type!=list) |
348 |
|
return; |
349 |
|
|
350 |
|
/* The first list element is the new stack head */ |
351 |
|
new_head= temp= (*stack_head)->content.ptr; |
352 |
toss(stack_head); |
toss(stack_head); |
353 |
|
|
354 |
|
/* Search the end of the list */ |
355 |
|
while(temp->next!=NULL) |
356 |
|
temp= temp->next; |
357 |
|
|
358 |
|
/* Connect the the tail of the list with the old stack head */ |
359 |
|
temp->next= *stack_head; |
360 |
|
*stack_head= new_head; /* ...and voila! */ |
361 |
} |
} |
362 |
|
|
363 |
extern void nl() |
/* Swap the two top elements on the stack. */ |
364 |
|
extern void swap(stackitem** stack_head) |
365 |
{ |
{ |
366 |
printf("\n"); |
stackitem* temp= (*stack_head); |
367 |
|
|
368 |
|
if((*stack_head)==NULL || (*stack_head)->next==NULL) |
369 |
|
return; |
370 |
|
|
371 |
|
*stack_head= (*stack_head)->next; |
372 |
|
temp->next= (*stack_head)->next; |
373 |
|
(*stack_head)->next= temp; |
374 |
|
} |
375 |
|
|
376 |
|
/* Compares two elements by reference. */ |
377 |
|
extern void eq(stackitem** stack_head) |
378 |
|
{ |
379 |
|
void *left, *right; |
380 |
|
int result; |
381 |
|
|
382 |
|
if((*stack_head)==NULL || (*stack_head)->next==NULL) |
383 |
|
return; |
384 |
|
|
385 |
|
left= (*stack_head)->content.ptr; |
386 |
|
swap(stack_head); |
387 |
|
right= (*stack_head)->content.ptr; |
388 |
|
result= (left==right); |
389 |
|
|
390 |
|
toss(stack_head); toss(stack_head); |
391 |
|
push_val(stack_head, (left==right)); |
392 |
|
} |
393 |
|
|
394 |
|
/* Negates the top element on the stack. */ |
395 |
|
extern void not(stackitem** stack_head) |
396 |
|
{ |
397 |
|
int value; |
398 |
|
|
399 |
|
if((*stack_head)==NULL || (*stack_head)->type!=value) |
400 |
|
return; |
401 |
|
|
402 |
|
value= (*stack_head)->content.val; |
403 |
|
toss(stack_head); |
404 |
|
push_val(stack_head, !value); |
405 |
|
} |
406 |
|
|
407 |
|
/* Compares the two top elements on the stack and return 0 if they're the |
408 |
|
same. */ |
409 |
|
extern void neq(stackitem** stack_head) |
410 |
|
{ |
411 |
|
eq(stack_head); |
412 |
|
not(stack_head); |
413 |
|
} |
414 |
|
|
415 |
|
/* Give a symbol some content. */ |
416 |
|
extern void def(stackitem** stack_head) |
417 |
|
{ |
418 |
|
stackitem *temp, *value; |
419 |
|
|
420 |
|
if(*stack_head==NULL || (*stack_head)->next==NULL |
421 |
|
|| (*stack_head)->type!=ref) |
422 |
|
return; |
423 |
|
|
424 |
|
temp= (*stack_head)->content.ptr; |
425 |
|
value= (*stack_head)->next; |
426 |
|
temp->content= value->content; |
427 |
|
value->content.ptr=NULL; |
428 |
|
temp->type= value->type; |
429 |
|
|
430 |
|
toss(stack_head); toss(stack_head); |
431 |
|
} |
432 |
|
|
433 |
|
/* Quit stack. */ |
434 |
|
extern void quit() |
435 |
|
{ |
436 |
|
exit(EXIT_SUCCESS); |
437 |
} |
} |
438 |
|
|
439 |
int main() |
int main() |
451 |
printf("okidok\n "); |
printf("okidok\n "); |
452 |
} |
} |
453 |
|
|
454 |
|
exit(EXIT_SUCCESS); |
|
return EXIT_SUCCESS; |
|
455 |
} |
} |
456 |
|
|
457 |
/* Local Variables: */ |
/* Local Variables: */ |