1 /* $NetBSD: svc_fdset.c,v 1.7 2015/11/07 16:58:24 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2015 The NetBSD Foundation, Inc. 5 * All rights resefdsed. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Christos Zoulas. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __RCSID("$NetBSD: svc_fdset.c,v 1.7 2015/11/07 16:58:24 christos Exp $"); 34 35 36 #include "reentrant.h" 37 38 #include <sys/fd_set.h> 39 40 #include <rpc/rpc.h> 41 42 #ifdef FDSET_DEBUG 43 #include <stdio.h> 44 #include <stdarg.h> 45 #include <unistd.h> 46 #include <lwp.h> 47 #endif 48 #include <stdlib.h> 49 #include <string.h> 50 51 #include "svc_fdset.h" 52 53 #undef svc_fdset 54 #undef svc_maxfd 55 extern __fd_set_256 svc_fdset; 56 extern int svc_maxfd; 57 58 struct svc_fdset { 59 fd_set *fdset; 60 int fdmax; 61 int fdsize; 62 }; 63 64 /* The single threaded, one global fd_set version */ 65 static struct svc_fdset __svc_fdset; 66 67 static thread_key_t fdsetkey = -2; 68 69 #ifdef FDSET_DEBUG 70 71 static void __printflike(3, 0) 72 svc_header(const char *func, size_t line, const char *fmt, va_list ap) 73 { 74 fprintf(stderr, "%s[%d.%d]: %s, %zu: ", getprogname(), (int)getpid(), 75 (int)_lwp_self(), func, line); 76 vfprintf(stderr, fmt, ap); 77 va_end(ap); 78 } 79 80 static void __printflike(4, 5) 81 svc_fdset_print(const char *func, size_t line, struct svc_fdset *fds, 82 const char *fmt, ...) 83 { 84 va_list ap; 85 const char *did = ""; 86 87 va_start(ap, fmt); 88 svc_header(func, line, fmt, ap); 89 va_end(ap); 90 91 fprintf(stderr, "%p[%d] <", fds->fdset, fds->fdmax); 92 for (int i = 0; i <= fds->fdmax; i++) { 93 if (!FD_ISSET(i, fds->fdset)) 94 continue; 95 fprintf(stderr, "%s%d", did, i); 96 did = ", "; 97 } 98 fprintf(stderr, ">\n"); 99 } 100 101 static void __printflike(3, 4) 102 svc_print(const char *func, size_t line, const char *fmt, ...) 103 { 104 va_list ap; 105 106 va_start(ap, fmt); 107 svc_header(func, line, fmt, ap); 108 va_end(ap); 109 fprintf(stderr, "\n"); 110 } 111 112 #define DPRINTF(...) svc_print(__func__, __LINE__, __VA_ARGS__) 113 #define DPRINTF_FDSET(...) svc_fdset_print(__func__, __LINE__, __VA_ARGS__) 114 115 #else 116 117 #define DPRINTF(...) 118 #define DPRINTF_FDSET(...) 119 120 #endif 121 122 123 static inline void 124 svc_fdset_sanitize(struct svc_fdset *fds) 125 { 126 while (fds->fdmax >= 0 && !FD_ISSET(fds->fdmax, fds->fdset)) 127 fds->fdmax--; 128 /* Compat update */ 129 if (fds == &__svc_fdset) { 130 svc_fdset = *(__fd_set_256 *)__svc_fdset.fdset; 131 svc_maxfd = __svc_fdset.fdmax; 132 } 133 } 134 135 static void 136 svc_fdset_free(void *v) 137 { 138 struct svc_fdset *fds = v; 139 DPRINTF_FDSET(fds, "free"); 140 141 free(fds->fdset); 142 free(fds); 143 } 144 145 static struct svc_fdset * 146 svc_fdset_resize(int fd, struct svc_fdset *fds) 147 { 148 if (fds->fdset && fd < fds->fdsize) { 149 DPRINTF_FDSET(fds, "keeping %d < %d", fd, fds->fdsize); 150 return fds; 151 } 152 153 fd += FD_SETSIZE; 154 155 char *newfdset = realloc(fds->fdset, __NFD_BYTES(fd)); 156 if (newfdset == NULL) 157 return NULL; 158 159 memset(newfdset + __NFD_BYTES(fds->fdsize), 0, 160 __NFD_BYTES(fd) - __NFD_BYTES(fds->fdsize)); 161 162 163 fds->fdset = (void *)newfdset; 164 DPRINTF_FDSET(fds, "resize %d > %d", fd, fds->fdsize); 165 fds->fdsize = fd; 166 167 return fds; 168 } 169 170 static struct svc_fdset * 171 svc_fdset_alloc(int fd) 172 { 173 struct svc_fdset *fds; 174 175 if (!__isthreaded || fdsetkey == -2) 176 return svc_fdset_resize(fd, &__svc_fdset); 177 178 if (fdsetkey == -1) 179 thr_keycreate(&fdsetkey, svc_fdset_free); 180 181 if ((fds = thr_getspecific(fdsetkey)) == NULL) { 182 183 fds = calloc(1, sizeof(*fds)); 184 if (fds == NULL) 185 return NULL; 186 187 (void)thr_setspecific(fdsetkey, fds); 188 189 if (__svc_fdset.fdsize != 0) { 190 *fds = __svc_fdset; 191 DPRINTF("switching to %p", fds->fdset); 192 } else { 193 DPRINTF("first thread time %p", fds->fdset); 194 } 195 } else { 196 DPRINTF("again for %p", fds->fdset); 197 if (fd < fds->fdsize) 198 return fds; 199 } 200 201 return svc_fdset_resize(fd, fds); 202 } 203 204 /* allow each thread to have their own copy */ 205 void 206 svc_fdset_init(int flags) 207 { 208 DPRINTF("%x", flags); 209 if ((flags & SVC_FDSET_MT) && fdsetkey == -2) 210 fdsetkey = -1; 211 } 212 213 void 214 svc_fdset_zero(void) 215 { 216 DPRINTF("zero"); 217 struct svc_fdset *fds = svc_fdset_alloc(0); 218 memset(fds->fdset, 0, fds->fdsize); 219 fds->fdmax = -1; 220 } 221 222 int 223 svc_fdset_set(int fd) 224 { 225 struct svc_fdset *fds = svc_fdset_alloc(fd); 226 227 if (fds == NULL) 228 return -1; 229 230 FD_SET(fd, fds->fdset); 231 if (fd > fds->fdmax) 232 fds->fdmax = fd; 233 234 DPRINTF_FDSET(fds, "%d", fd); 235 236 svc_fdset_sanitize(fds); 237 return 0; 238 } 239 240 int 241 svc_fdset_isset(int fd) 242 { 243 struct svc_fdset *fds = svc_fdset_alloc(fd); 244 245 if (fds == NULL) 246 return -1; 247 248 DPRINTF_FDSET(fds, "%d", fd); 249 250 return FD_ISSET(fd, fds->fdset) != 0; 251 } 252 253 int 254 svc_fdset_clr(int fd) 255 { 256 struct svc_fdset *fds = svc_fdset_alloc(fd); 257 258 if (fds == NULL) 259 return -1; 260 261 FD_CLR(fd, fds->fdset); 262 DPRINTF_FDSET(fds, "%d", fd); 263 264 svc_fdset_sanitize(fds); 265 return 0; 266 } 267 268 fd_set * 269 svc_fdset_copy(const fd_set *orig) 270 { 271 int size = svc_fdset_getsize(0); 272 fd_set *copy = calloc(1, __NFD_BYTES(size)); 273 if (copy == NULL) 274 return NULL; 275 if (orig) 276 memcpy(copy, orig, __NFD_BYTES(size)); 277 return copy; 278 } 279 280 fd_set * 281 svc_fdset_get(void) 282 { 283 struct svc_fdset *fds = svc_fdset_alloc(0); 284 285 if (fds == NULL) 286 return NULL; 287 288 DPRINTF_FDSET(fds, "get"); 289 svc_fdset_sanitize(fds); 290 return fds->fdset; 291 } 292 293 int * 294 svc_fdset_getmax(void) 295 { 296 struct svc_fdset *fds = svc_fdset_alloc(0); 297 298 if (fds == NULL) 299 return NULL; 300 301 DPRINTF_FDSET(fds, "getmax"); 302 svc_fdset_sanitize(fds); 303 return &fds->fdmax; 304 } 305 306 int 307 svc_fdset_getsize(int fd) 308 { 309 struct svc_fdset *fds = svc_fdset_alloc(fd); 310 311 if (fds == NULL) 312 return -1; 313 314 DPRINTF_FDSET(fds, "getsize"); 315 return fds->fdsize; 316 } 317