Create a function pointer which takes a function pointer as an argument
I'm trying to create a function pointer that takes a function pointer as an argument, but am not sure how to go about it... I was advised to try typedef-ing one of my function pointers, but get the same error. Could someone help me with the correct syntax?
int
186 main(int argc, char **argv)
187 {
188 int i;
194 typedef int (*search_alg) (int *, int, int);
195 typedef int (*search) (search_alg);
196 set_t (*intersect_alg) (list_t *, (search));
197
198 clo_t *iopts = parse_args(argc, argv);
199
200 /* select interstion algorithm */
201 switch (iopts->imode) {
202 case SVS:
203 fprintf(stdout, "ALGORITHM : SvS\n");
204 intersect_alg = svs;
205 break;
206 case SEQ:
207 fprintf(stdout, "ALGORITHM : Sequential\n");
208 intersect_alg = sequential;
209 break;
210 case ADP:
211 fprintf(stdout, "ALGORITHM : Adaptive\n");
212 intersect_alg = adaptive;
213 break;
214 default:
215 fprintf(stdout, "ALGORITHM : Unknown\n");
216 return (EXIT_FAILURE);
217 }
218
219 /* select fsearch algorithm */
220 switch (iopts->mode) {
221 case LIN:
222 fprintf(stdout, "F-SEARCH : Linear\n");
223 search = linear_fsearch;
224 break;
225 case BIN:
226 fprintf(stdout, "F-SEARCH : Binary\n");
227 search = binary_fsearch;
228 break;
229 case INP:
230 fprintf(stdout, "F-SEARCH : Interpolation\n");
231 开发者_运维百科 search = interpolation_fsearch;
232 break;
233 case EXP:
234 fprintf(stdout, "F-SEARCH : Exponential\n");
235 search = exponential_fsearch;
236 break;
237 default:
238 fprintf(stdout, "F-SEARCH : Unknown\n");
239 return (EXIT_FAILURE);
240 }
241
244
245 /* perform intersection and run timings */
246 for (i = 0; i < iopts->runs; i++) {
248 /* perform intersect search */
249 intersect_alg (iopts->data_files, search);
252 }
The line I'm trying to make work is 249, I originally tried
int (*search_alg) (int *, int, int);
set_t (*intersect_alg) (list_t *, (*) (int *, int, int);
and would probably prefer to do it that way if possible. The error I'm getting is:
main.c:204: warning: assignment from incompatible pointer type
main.c:208: warning: assignment from incompatible pointer type
main.c:212: warning: assignment from incompatible pointer type
And the functions I'm pointing to are:
22 /** Finger Search Operations for array sets **/
23 int linear_fsearch(int *set, int len, int key);
24 int binary_fsearch(int *set, int len, int key);
25 int interpolation_fsearch(int *set, int len, int key);
26 int exponential_fsearch(int *set, int len, int key);
27
28 /** Intersect Algorithms **/
29 set_t *svs(list_t * list, int (*srch_alg) (int *, int, int));
30 set_t *sequential(list_t * list, int (*srch_alg) (int *, int, int ));
31 set_t *adaptive(list_t * list, int (*srch_alg) (int *, int, int));
Can anyone see what I'm doing wrong? I can't figure it out. Thanks!
Rhys.
The declaration you need for intersect_alg
is
set_t *(*intersect_alg)(list_t *, int (*)(int *, int, int));
精彩评论