}; 这个就是新定义结构体,跟原来稍微有点变化只是把64改为1,有些同学可能见多很多这样的写法,这种写法我也在一些项目使用了。这种写法可以fd_array动态变化。 win_fd_set * Set = (win_fd_set*)malloc(sizeof(win_fd_set) + sizoef(SCOEKT) * 10); Set->fd_array 可以放11 个 SOCKET,因为我的内存大小足够放11个SOCKET。 请记住内存是没有数据格式,只要足够大小,随便你怎么放。数据格式只是方便我们管理和处理数据而已。 这样就解决64个大小限制。。我其实一直很好奇为什么中国书籍都是一样的,libevent已经出来好久了,但也没有看到有人说这一点,可能是高手们都不屑。 现在渐渐喜欢看开源的代码,不喜欢看书籍了,喜欢在代码中学习他们是怎么组织一个好项目。 有时候感慨:高手用c 写着漂亮的c++代码,而我等菜鸟却用c++ 写丑陋的c代码。。 我顺便把他整个定义结构和函数给大家贴出来,免大家还要自己去下libevent,不过推荐没有看过libevent同学,可以稍微看一下。
1 volatile double SIGFPE_REQ = 0.0f; 2 3 struct idx_info { 4 int read_pos_plus1; 5 int write_pos_plus1; 6 }; 7 8 struct win32op { 9 unsigned num_fds_in_fd_sets; 10 int resize_out_sets; 11 struct win_fd_set *readset_in; 12 struct win_fd_set *writeset_in; 13 struct win_fd_set *readset_out; 14 struct win_fd_set *writeset_out; 15 struct win_fd_set *exset_out; 16 unsigned signals_are_broken : 1; 17 }; 18 19 static void *win32_init(struct event_base *); 20 static int win32_add(struct event_base *, evutil_socket_t, short old, short events, void *_idx); 21 static int win32_del(struct event_base *, evutil_socket_t, short old, short events, void *_idx); 22 static int win32_dispatch(struct event_base *base, struct timeval *); 23 static void win32_dealloc(struct event_base *); 24 25 struct eventop win32ops = { 26 "win32", 27 win32_init, 28 win32_add, 29 win32_del, 30 win32_dispatch, 31 win32_dealloc, 32 0, /* doesn't need reinit */ 33 0, /* No features supported. */ 34 sizeof(struct idx_info), 35 }; 36 37 #define FD_SET_ALLOC_SIZE(n) ((sizeof(struct win_fd_set) + ((n)-1)*sizeof(SOCKET))) 38 39 static int 40 grow_fd_sets(struct win32op *op, unsigned new_num_fds) 41 { 42 size_t size; 43 44 EVUTIL_ASSERT(new_num_fds >= op->readset_in->fd_count && 45 new_num_fds >= op->writeset_in->fd_count); 46 EVUTIL_ASSERT(new_num_fds >= 1); 47 48 size = FD_SET_ALLOC_SIZE(new_num_fds); 49 if (!(op->readset_in = mm_realloc(op->readset_in, size))) 50 return (-1); 51 if (!(op->writeset_in = mm_realloc(op->writeset_in, size))) 52 return (-1); 53 op->resize_out_sets = 1; 54 op->num_fds_in_fd_sets = new_num_fds; 55 return (0); 56 } 57 58 static int 59 do_fd_set(struct win32op *op, struct idx_info *ent, evutil_socket_t s, int read) 60 { 61 struct win_fd_set *set = read ? op->readset_in : op->writeset_in; 62 if (read) { 63 if (ent->read_pos_plus1 > 0) 64 return (0); 65 } else { 66 if (ent->write_pos_plus1 > 0) 67 return (0); 68 } 69 if (set->fd_count == op->num_fds_in_fd_sets) { 70 if (grow_fd_sets(op, op->num_fds_in_fd_sets*2)) 71 return (-1); 72 /* set pointer will have changed and needs reiniting! */ 73 set = read ? op->readset_in : op->writeset_in; 74 } 75 set->fd_array[set->fd_count] = s; 76 if (read) 77 ent->read_pos_plus1 = set->fd_count+1; 78 else 79 ent->write_pos_plus1 = set->fd_count+1; 80 return (set->fd_count++); 81 } 82 83 static int 84 do_fd_clear(struct event_base *base, 85 struct win32op *op, struct idx_info *ent, int read) 86 { 87 int i; 88 struct win_fd_set *set = read ? op->readset_in : op->writeset_in; 89 if (read) { 90 i = ent->read_pos_plus1 - 1; 91 ent->read_pos_plus1 = 0; 92 } else { 93 i = ent->write_pos_plus1 - 1; 94 ent->write_pos_plus1 = 0; 95 } 96 if (i < 0) 97 return (0); 98 if (--set->fd_count != (unsigned)i) { 99 struct idx_info *ent2; 100 SOCKET s2; 101 s2 = set->fd_array[i] = set->fd_array[set->fd_count]; 102 103 ent2 = evmap_io_get_fdinfo(&base->io, s2); 104 105 if (!ent2) /* This indicates a bug. */ 106 return (0); 107 if (read) 108 ent2->read_pos_plus1 = i+1; 109 else 110 ent2->write_pos_plus1 = i+1; 111 } 112 return (0); 113 } 114 115 #define NEVENT 32 116 void * 117 win32_init(struct event_base *_base) 118 { 119 struct win32op *winop; 120 size_t size; 121 if (!(winop = mm_calloc(1, sizeof(struct win32op)))) 122 return NULL; 123 winop->num_fds_in_fd_sets = NEVENT; 124 size = FD_SET_ALLOC_SIZE(NEVENT); 125 if (!(winop->readset_in = mm_malloc(size))) 126 goto err; 127 if (!(winop->writeset_in = mm_malloc(size))) 128 goto err; 129 if (!(winop->readset_out = mm_malloc(size))) 130 goto err; 131 if (!(winop->writeset_out = mm_malloc(size))) 132 goto err; 133 if (!(winop->exset_out = mm_malloc(size))) 134 goto err; 135 winop->readset_in->fd_count = winop->writeset_in->fd_count = 0; 136 winop->readset_out->fd_count = winop->writeset_out->fd_count 137 = winop->exset_out->fd_count = 0; 138 139 if (evsig_init(_base) < 0) 140 winop->signals_are_broken = 1; 141 142 return (winop); 143 err: 144 XFREE(winop->readset_in); 145 XFREE(winop->writeset_in); 146 XFREE(winop->readset_out); 147 XFREE(winop->writeset_out); 148 XFREE(winop->exset_out); 149 XFREE(winop); 150 return (NULL); 151 } 152 153 int 154 win32_add(struct event_base *base, evutil_socket_t fd, 155 short old, short events, void *_idx) 156 { 157 struct win32op *win32op = base->evbase; 158 struct idx_info *idx = _idx; 159 160 if ((events & EV_SIGNAL) && win32op->signals_are_broken) 161 return (-1); 162 163 if (!(events & (EV_READ|EV_WRITE))) 164 return (0); 165 166 event_debug(("%s: adding event for %d", __func__, (int)fd)); 167 if (events & EV_READ) { 168 if (do_fd_set(win32op, idx, fd, 1)<0) 169 return (-1); 170 } 171 if (events & EV_WRITE) { 172 if (do_fd_set(win32op, idx, fd, 0)<0) 173 return (-1); 174 } 175 return (0); 176 } 177 178 int 179 win32_del(struct event_base *base, evutil_socket_t fd, short old, short events, 180 void *_idx) 181 { 182 struct win32op *win32op = base->evbase; 183 struct idx_info *idx = _idx; 184 185 event_debug(("%s: Removing event for "EV_SOCK_FMT, 186 __func__, EV_SOCK_ARG(fd))); 187 if (events & EV_READ) 188 do_fd_clear(base, win32op, idx, 1); 189 if (events & EV_WRITE) 190 do_fd_clear(base, win32op, idx, 0); 191 192 return 0; 193 } 194 195 static void 196 fd_set_copy(struct win_fd_set *out, const struct win_fd_set *in) 197 { 198 out->fd_count = in->fd_count; 199 memcpy(out->fd_array, in->fd_array, in->fd_count * (sizeof(SOCKET))); 200 } 201 202 /* 203 static void dump_fd_set(struct win_fd_set *s) 204 { 205 unsigned int i; 206 printf("[ "); 207 for(i=0;i<s->fd_count;++i) 208 printf("%d ",(int)s->fd_array[i]); 209 printf("]\n"); 210 } 211 */ 212 213 int 214 win32_dispatch(struct event_base *base, struct timeval *tv) 215 { 216 struct win32op *win32op = base->evbase; 217 int res = 0; 218 unsigned j, i; 219 int fd_count; 220 SOCKET s; 221 222 if (win32op->resize_out_sets) { 223 size_t size = FD_SET_ALLOC_SIZE(win32op->num_fds_in_fd_sets); 224 if (!(win32op->readset_out = mm_realloc(win32op->readset_out, size))) 225 return (-1); 226 if (!(win32op->exset_out = mm_realloc(win32op->exset_out, size))) 227 return (-1); 228 if (!(win32op->writeset_out = mm_realloc(win32op->writeset_out, size))) 229 return (-1); 230 win32op->resize_out_sets = 0; 231 } 232 233 fd_set_copy(win32op->readset_out, win32op->readset_in); 234 fd_set_copy(win32op->exset_out, win32op->writeset_in); 235 fd_set_copy(win32op->writeset_out, win32op->writeset_in); 236 237 fd_count = 238 (win32op->readset_out->fd_count > win32op->writeset_out->fd_count) ? 239 win32op->readset_out->fd_count : win32op->writeset_out->fd_count; 240 241 if (!fd_count) { 242 long msec = tv ? evutil_tv_to_msec(tv) : LONG_MAX; 243 /* Sleep's DWORD argument is unsigned long */ 244 if (msec < 0) 245 msec = LONG_MAX; 246 /* Windows doesn't like you to call select() with no sockets */ 247 Sleep(msec); 248 return (0); 249 } 250 251 EVBASE_RELEASE_LOCK(base, th_base_lock); 252 253 res = select(fd_count, 254 (struct fd_set*)win32op->readset_out, 255 (struct fd_set*)win32op->writeset_out, 256 (struct fd_set*)win32op->exset_out, tv); 257 258 EVBASE_ACQUIRE_LOCK(base, th_base_lock); 259 260 event_debug(("%s: select returned %d", __func__, res)); 261 262 if (res <= 0) { 263 return res; 264 } 265 266 if (win32op->readset_out->fd_count) { 267 i = rand() % win32op->readset_out->fd_count; 268 for (j=0; j<win32op->readset_out->fd_count; ++j) { 269 if (++i >= win32op->readset_out->fd_count) 270 i = 0; 271 s = win32op->readset_out->fd_array[i]; 272 evmap_io_active(base, s, EV_READ); 273 } 274 } 275 if (win32op->exset_out->fd_count) { 276 i = rand() % win32op->exset_out->fd_count; 277 for (j=0; j<win32op->exset_out->fd_count; ++j) { 278 if (++i >= win32op->exset_out->fd_count) 279 i = 0; 280 s = win32op->exset_out->fd_array[i]; 281 evmap_io_active(base, s, EV_WRITE); 282 } 283 } 284 if (win32op->writeset_out->fd_count) { 285 SOCKET s; 286 i = rand() % win32op->writeset_out->fd_count; 287 for (j=0; j<win32op->writeset_out->fd_count; ++j) { 288 if (++i >= win32op->writeset_out->fd_count) 289 i = 0; 290 s = win32op->writeset_out->fd_array[i]; 291 evmap_io_active(base, s, EV_WRITE); 292 } 293 } 294 return (0); 295 } 296 297 void 298 win32_dealloc(struct event_base *_base) 299 { 300 struct win32op *win32op = _base->evbase; 301 302 evsig_dealloc(_base); 303 if (win32op->readset_in) 304 mm_free(win32op->readset_in); 305 if (win32op->writeset_in) 306 mm_free(win32op->writeset_in); 307 if (win32op->readset_out) 308 mm_free(win32op->readset_out); 309 if (win32op->writeset_out) 310 mm_free(win32op->writeset_out); 311 if (win32op->exset_out) 312 mm_free(win32op->exset_out); 313 /* XXXXX free the tree. */ 314 315 memset(win32op, 0, sizeof(win32op)); 316 mm_free(win32op); 317 }