src/anet.c

   1 /* anet.c -- Basic TCP socket stuff made a bit less boring
   2  *
   3  * Copyright (c) 2006-2010, Salvatore Sanfilippo <antirez at gmail dot com>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are met:
   8  *
   9  *   * Redistributions of source code must retain the above copyright notice,
  10  *     this list of conditions and the following disclaimer.
  11  *   * Redistributions in binary form must reproduce the above copyright
  12  *     notice, this list of conditions and the following disclaimer in the
  13  *     documentation and/or other materials provided with the distribution.
  14  *   * Neither the name of Redis nor the names of its contributors may be used
  15  *     to endorse or promote products derived from this software without
  16  *     specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  28  * POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #include "fmacros.h"
  32
  33 #include <sys/types.h>
  34 #include <sys/socket.h>
  35 #include <sys/un.h>
  36 #include <netinet/in.h>
  37 #include <netinet/tcp.h>
  38 #include <arpa/inet.h>
  39 #include <unistd.h>
  40 #include <fcntl.h>
  41 #include <string.h>
  42 #include <netdb.h>
  43 #include <errno.h>
  44 #include <stdarg.h>
  45 #include <stdio.h>
  46
  47 #include "anet.h"
  48
  49 static void anetSetError(char *err, const char *fmt, ...)
  50 {
  51     va_list ap;
  52
  53     if (!err) return;
  54     va_start(ap, fmt);
  55     vsnprintf(err, ANET_ERR_LEN, fmt, ap);
  56     va_end(ap);
  57 }
  58
  59 int anetNonBlock(char *err, int fd)
  60 {
  61     int flags;
  62
  63     /* Set the socket nonblocking.
  64      * Note that fcntl(2) for F_GETFL and F_SETFL can't be
  65      * interrupted by a signal. */
  66     if ((flags = fcntl(fd, F_GETFL)) == -1) {
  67         anetSetError(err, "fcntl(F_GETFL): %s\n", strerror(errno));
  68         return ANET_ERR;
  69     }
  70     if (fcntl(fd, F_SETFL, flags | O_NONBLOCK) == -1) {
  71         anetSetError(err, "fcntl(F_SETFL,O_NONBLOCK): %s\n", strerror(errno));
  72         return ANET_ERR;
  73     }
  74     return ANET_OK;
  75 }
  76
  77 int anetTcpNoDelay(char *err, int fd)
  78 {
  79     int yes = 1;
  80     if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &yes, sizeof(yes)) == -1)
  81     {
  82         anetSetError(err, "setsockopt TCP_NODELAY: %s\n", strerror(errno));
  83         return ANET_ERR;
  84     }
  85     return ANET_OK;
  86 }
  87
  88 int anetSetSendBuffer(char *err, int fd, int buffsize)
  89 {
  90     if (setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &buffsize, sizeof(buffsize)) == -1)
  91     {
  92         anetSetError(err, "setsockopt SO_SNDBUF: %s\n", strerror(errno));
  93         return ANET_ERR;
  94     }
  95     return ANET_OK;
  96 }
  97
  98 int anetTcpKeepAlive(char *err, int fd)
  99 {
 100     int yes = 1;
 101     if (setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, &yes, sizeof(yes)) == -1) {
 102         anetSetError(err, "setsockopt SO_KEEPALIVE: %s\n", strerror(errno));
 103         return ANET_ERR;
 104     }
 105     return ANET_OK;
 106 }
 107
 108 int anetResolve(char *err, char *host, char *ipbuf)
 109 {
 110     struct sockaddr_in sa;
 111
 112     sa.sin_family = AF_INET;
 113     if (inet_aton(host, &sa.sin_addr) == 0) {
 114         struct hostent *he;
 115
 116         he = gethostbyname(host);
 117         if (he == NULL) {
 118             anetSetError(err, "can't resolve: %s\n", host);
 119             return ANET_ERR;
 120         }
 121         memcpy(&sa.sin_addr, he->h_addr, sizeof(struct in_addr));
 122     }
 123     strcpy(ipbuf,inet_ntoa(sa.sin_addr));
 124     return ANET_OK;
 125 }
 126
 127 #define ANET_CONNECT_NONE 0
 128 #define ANET_CONNECT_NONBLOCK 1
 129 static int anetTcpGenericConnect(char *err, char *addr, int port, int flags)
 130 {
 131     int s, on = 1;
 132     struct sockaddr_in sa;
 133
 134     if ((s = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
 135         anetSetError(err, "creating socket: %s\n", strerror(errno));
 136         return ANET_ERR;
 137     }
 138     /* Make sure connection-intensive things like the redis benckmark
 139      * will be able to close/open sockets a zillion of times */
 140     setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
 141
 142     sa.sin_family = AF_INET;
 143     sa.sin_port = htons(port);
 144     if (inet_aton(addr, &sa.sin_addr) == 0) {
 145         struct hostent *he;
 146
 147         he = gethostbyname(addr);
 148         if (he == NULL) {
 149             anetSetError(err, "can't resolve: %s\n", addr);
 150             close(s);
 151             return ANET_ERR;
 152         }
 153         memcpy(&sa.sin_addr, he->h_addr, sizeof(struct in_addr));
 154     }
 155     if (flags & ANET_CONNECT_NONBLOCK) {
 156         if (anetNonBlock(err,s) != ANET_OK)
 157             return ANET_ERR;
 158     }
 159     if (connect(s, (struct sockaddr*)&sa, sizeof(sa)) == -1) {
 160         if (errno == EINPROGRESS &&
 161             flags & ANET_CONNECT_NONBLOCK)
 162             return s;
 163
 164         anetSetError(err, "connect: %s\n", strerror(errno));
 165         close(s);
 166         return ANET_ERR;
 167     }
 168     return s;
 169 }
 170
 171 int anetTcpConnect(char *err, char *addr, int port)
 172 {
 173     return anetTcpGenericConnect(err,addr,port,ANET_CONNECT_NONE);
 174 }
 175
 176 int anetTcpNonBlockConnect(char *err, char *addr, int port)
 177 {
 178     return anetTcpGenericConnect(err,addr,port,ANET_CONNECT_NONBLOCK);
 179 }
 180
 181 int anetUnixGenericConnect(char *err, char *path, int flags)
 182 {
 183     int s;
 184     struct sockaddr_un sa;
 185
 186     if ((s = socket(AF_LOCAL,SOCK_STREAM,0)) == -1) {
 187         anetSetError(err, "creating socket: %s\n", strerror(errno));
 188         return ANET_ERR;
 189     }
 190     sa.sun_family = AF_LOCAL;
 191     strncpy(sa.sun_path,path,sizeof(sa.sun_path)-1);
 192     if (flags & ANET_CONNECT_NONBLOCK) {
 193         if (anetNonBlock(err,s) != ANET_OK)
 194             return ANET_ERR;
 195     }
 196     if (connect(s,(struct sockaddr*)&sa,sizeof(sa)) == -1) {
 197         if (errno == EINPROGRESS &&
 198             flags & ANET_CONNECT_NONBLOCK)
 199             return s;
 200
 201         anetSetError(err, "connect: %s\n", strerror(errno));
 202         close(s);
 203         return ANET_ERR;
 204     }
 205     return s;
 206 }
 207
 208 int anetUnixConnect(char *err, char *path)
 209 {
 210     return anetUnixGenericConnect(err,path,ANET_CONNECT_NONE);
 211 }
 212
 213 int anetUnixNonBlockConnect(char *err, char *path)
 214 {
 215     return anetUnixGenericConnect(err,path,ANET_CONNECT_NONBLOCK);
 216 }
 217
 218 /* Like read(2) but make sure 'count' is read before to return
 219  * (unless error or EOF condition is encountered) */
 220 int anetRead(int fd, char *buf, int count)
 221 {
 222     int nread, totlen = 0;
 223     while(totlen != count) {
 224         nread = read(fd,buf,count-totlen);
 225         if (nread == 0) return totlen;
 226         if (nread == -1) return -1;
 227         totlen += nread;
 228         buf += nread;
 229     }
 230     return totlen;
 231 }
 232
 233 /* Like write(2) but make sure 'count' is read before to return
 234  * (unless error is encountered) */
 235 int anetWrite(int fd, char *buf, int count)
 236 {
 237     int nwritten, totlen = 0;
 238     while(totlen != count) {
 239         nwritten = write(fd,buf,count-totlen);
 240         if (nwritten == 0) return totlen;
 241         if (nwritten == -1) return -1;
 242         totlen += nwritten;
 243         buf += nwritten;
 244     }
 245     return totlen;
 246 }
 247
 248 int anetTcpServer(char *err, int port, char *bindaddr)
 249 {
 250     int s, on = 1;
 251     struct sockaddr_in sa;
 252
 253     if ((s = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
 254         anetSetError(err, "socket: %s\n", strerror(errno));
 255         return ANET_ERR;
 256     }
 257     if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1) {
 258         anetSetError(err, "setsockopt SO_REUSEADDR: %s\n", strerror(errno));
 259         close(s);
 260         return ANET_ERR;
 261     }
 262     memset(&sa,0,sizeof(sa));
 263     sa.sin_family = AF_INET;
 264     sa.sin_port = htons(port);
 265     sa.sin_addr.s_addr = htonl(INADDR_ANY);
 266     if (bindaddr) {
 267         if (inet_aton(bindaddr, &sa.sin_addr) == 0) {
 268             anetSetError(err, "Invalid bind address\n");
 269             close(s);
 270             return ANET_ERR;
 271         }
 272     }
 273     if (bind(s, (struct sockaddr*)&sa, sizeof(sa)) == -1) {
 274         anetSetError(err, "bind: %s\n", strerror(errno));
 275         close(s);
 276         return ANET_ERR;
 277     }
 278     if (listen(s, 511) == -1) { /* the magic 511 constant is from nginx */
 279         anetSetError(err, "listen: %s\n", strerror(errno));
 280         close(s);
 281         return ANET_ERR;
 282     }
 283     return s;
 284 }
 285
 286 int anetUnixServer(char *err, char *path)
 287 {
 288     int s;
 289     struct sockaddr_un sa;
 290
 291     if ((s = socket(AF_LOCAL,SOCK_STREAM,0)) == -1) {
 292         anetSetError(err, "socket: %s\n", strerror(errno));
 293         return ANET_ERR;
 294     }
 295     memset(&sa,0,sizeof(sa));
 296     sa.sun_family = AF_LOCAL;
 297     strncpy(sa.sun_path,path,sizeof(sa.sun_path)-1);
 298     if (bind(s,(struct sockaddr*)&sa,SUN_LEN(&sa)) == -1) {
 299         anetSetError(err, "bind: %s\n", strerror(errno));
 300         close(s);
 301         return ANET_ERR;
 302     }
 303     if (listen(s, 511) == -1) { /* the magic 511 constant is from nginx */
 304         anetSetError(err, "listen: %s\n", strerror(errno));
 305         close(s);
 306         return ANET_ERR;
 307     }
 308     return s;
 309 }
 310
 311 int anetAccept(char *err, int serversock, char *ip, int *port)
 312 {
 313     int fd;
 314     struct sockaddr_in sa;
 315     unsigned int saLen;
 316
 317     while(1) {
 318         saLen = sizeof(sa);
 319         fd = accept(serversock, (struct sockaddr*)&sa, &saLen);
 320         if (fd == -1) {
 321             if (errno == EINTR)
 322                 continue;
 323             else {
 324                 anetSetError(err, "accept: %s\n", strerror(errno));
 325                 return ANET_ERR;
 326             }
 327         }
 328         break;
 329     }
 330     if (ip) strcpy(ip,inet_ntoa(sa.sin_addr));
 331     if (port) *port = ntohs(sa.sin_port);
 332     return fd;
 333 }