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-rw-r--r--src/anet.c707
1 files changed, 707 insertions, 0 deletions
diff --git a/src/anet.c b/src/anet.c
new file mode 100644
index 0000000..10840fc
--- /dev/null
+++ b/src/anet.c
@@ -0,0 +1,707 @@
+/* anet.c -- Basic TCP socket stuff made a bit less boring
+ *
+ * Copyright (c) 2006-2012, Salvatore Sanfilippo <antirez at gmail dot com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * * Neither the name of Redis nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "fmacros.h"
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/un.h>
+#include <sys/time.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <arpa/inet.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <netdb.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+
+#include "anet.h"
+#include "config.h"
+
+#define UNUSED(x) (void)(x)
+
+static void anetSetError(char *err, const char *fmt, ...)
+{
+ va_list ap;
+
+ if (!err) return;
+ va_start(ap, fmt);
+ vsnprintf(err, ANET_ERR_LEN, fmt, ap);
+ va_end(ap);
+}
+
+int anetSetBlock(char *err, int fd, int non_block) {
+ int flags;
+
+ /* Set the socket blocking (if non_block is zero) or non-blocking.
+ * Note that fcntl(2) for F_GETFL and F_SETFL can't be
+ * interrupted by a signal. */
+ if ((flags = fcntl(fd, F_GETFL)) == -1) {
+ anetSetError(err, "fcntl(F_GETFL): %s", strerror(errno));
+ return ANET_ERR;
+ }
+
+ /* Check if this flag has been set or unset, if so,
+ * then there is no need to call fcntl to set/unset it again. */
+ if (!!(flags & O_NONBLOCK) == !!non_block)
+ return ANET_OK;
+
+ if (non_block)
+ flags |= O_NONBLOCK;
+ else
+ flags &= ~O_NONBLOCK;
+
+ if (fcntl(fd, F_SETFL, flags) == -1) {
+ anetSetError(err, "fcntl(F_SETFL,O_NONBLOCK): %s", strerror(errno));
+ return ANET_ERR;
+ }
+ return ANET_OK;
+}
+
+int anetNonBlock(char *err, int fd) {
+ return anetSetBlock(err,fd,1);
+}
+
+int anetBlock(char *err, int fd) {
+ return anetSetBlock(err,fd,0);
+}
+
+/* Enable the FD_CLOEXEC on the given fd to avoid fd leaks.
+ * This function should be invoked for fd's on specific places
+ * where fork + execve system calls are called. */
+int anetCloexec(int fd) {
+ int r;
+ int flags;
+
+ do {
+ r = fcntl(fd, F_GETFD);
+ } while (r == -1 && errno == EINTR);
+
+ if (r == -1 || (r & FD_CLOEXEC))
+ return r;
+
+ flags = r | FD_CLOEXEC;
+
+ do {
+ r = fcntl(fd, F_SETFD, flags);
+ } while (r == -1 && errno == EINTR);
+
+ return r;
+}
+
+/* Set TCP keep alive option to detect dead peers. The interval option
+ * is only used for Linux as we are using Linux-specific APIs to set
+ * the probe send time, interval, and count. */
+int anetKeepAlive(char *err, int fd, int interval)
+{
+ int val = 1;
+
+ if (setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, &val, sizeof(val)) == -1)
+ {
+ anetSetError(err, "setsockopt SO_KEEPALIVE: %s", strerror(errno));
+ return ANET_ERR;
+ }
+
+#ifdef __linux__
+ /* Default settings are more or less garbage, with the keepalive time
+ * set to 7200 by default on Linux. Modify settings to make the feature
+ * actually useful. */
+
+ /* Send first probe after interval. */
+ val = interval;
+ if (setsockopt(fd, IPPROTO_TCP, TCP_KEEPIDLE, &val, sizeof(val)) < 0) {
+ anetSetError(err, "setsockopt TCP_KEEPIDLE: %s\n", strerror(errno));
+ return ANET_ERR;
+ }
+
+ /* Send next probes after the specified interval. Note that we set the
+ * delay as interval / 3, as we send three probes before detecting
+ * an error (see the next setsockopt call). */
+ val = interval/3;
+ if (val == 0) val = 1;
+ if (setsockopt(fd, IPPROTO_TCP, TCP_KEEPINTVL, &val, sizeof(val)) < 0) {
+ anetSetError(err, "setsockopt TCP_KEEPINTVL: %s\n", strerror(errno));
+ return ANET_ERR;
+ }
+
+ /* Consider the socket in error state after three we send three ACK
+ * probes without getting a reply. */
+ val = 3;
+ if (setsockopt(fd, IPPROTO_TCP, TCP_KEEPCNT, &val, sizeof(val)) < 0) {
+ anetSetError(err, "setsockopt TCP_KEEPCNT: %s\n", strerror(errno));
+ return ANET_ERR;
+ }
+#elif defined(__APPLE__)
+ /* Set idle time with interval */
+ val = interval;
+ if (setsockopt(fd, IPPROTO_TCP, TCP_KEEPALIVE, &val, sizeof(val)) < 0) {
+ anetSetError(err, "setsockopt TCP_KEEPALIVE: %s\n", strerror(errno));
+ return ANET_ERR;
+ }
+#else
+ ((void) interval); /* Avoid unused var warning for non Linux systems. */
+#endif
+
+ return ANET_OK;
+}
+
+static int anetSetTcpNoDelay(char *err, int fd, int val)
+{
+ if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &val, sizeof(val)) == -1)
+ {
+ anetSetError(err, "setsockopt TCP_NODELAY: %s", strerror(errno));
+ return ANET_ERR;
+ }
+ return ANET_OK;
+}
+
+int anetEnableTcpNoDelay(char *err, int fd)
+{
+ return anetSetTcpNoDelay(err, fd, 1);
+}
+
+int anetDisableTcpNoDelay(char *err, int fd)
+{
+ return anetSetTcpNoDelay(err, fd, 0);
+}
+
+/* Set the socket send timeout (SO_SNDTIMEO socket option) to the specified
+ * number of milliseconds, or disable it if the 'ms' argument is zero. */
+int anetSendTimeout(char *err, int fd, long long ms) {
+ struct timeval tv;
+
+ tv.tv_sec = ms/1000;
+ tv.tv_usec = (ms%1000)*1000;
+ if (setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv)) == -1) {
+ anetSetError(err, "setsockopt SO_SNDTIMEO: %s", strerror(errno));
+ return ANET_ERR;
+ }
+ return ANET_OK;
+}
+
+/* Set the socket receive timeout (SO_RCVTIMEO socket option) to the specified
+ * number of milliseconds, or disable it if the 'ms' argument is zero. */
+int anetRecvTimeout(char *err, int fd, long long ms) {
+ struct timeval tv;
+
+ tv.tv_sec = ms/1000;
+ tv.tv_usec = (ms%1000)*1000;
+ if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv)) == -1) {
+ anetSetError(err, "setsockopt SO_RCVTIMEO: %s", strerror(errno));
+ return ANET_ERR;
+ }
+ return ANET_OK;
+}
+
+/* Resolve the hostname "host" and set the string representation of the
+ * IP address into the buffer pointed by "ipbuf".
+ *
+ * If flags is set to ANET_IP_ONLY the function only resolves hostnames
+ * that are actually already IPv4 or IPv6 addresses. This turns the function
+ * into a validating / normalizing function. */
+int anetResolve(char *err, char *host, char *ipbuf, size_t ipbuf_len,
+ int flags)
+{
+ struct addrinfo hints, *info;
+ int rv;
+
+ memset(&hints,0,sizeof(hints));
+ if (flags & ANET_IP_ONLY) hints.ai_flags = AI_NUMERICHOST;
+ hints.ai_family = AF_UNSPEC;
+ hints.ai_socktype = SOCK_STREAM; /* specify socktype to avoid dups */
+
+ if ((rv = getaddrinfo(host, NULL, &hints, &info)) != 0) {
+ anetSetError(err, "%s", gai_strerror(rv));
+ return ANET_ERR;
+ }
+ if (info->ai_family == AF_INET) {
+ struct sockaddr_in *sa = (struct sockaddr_in *)info->ai_addr;
+ inet_ntop(AF_INET, &(sa->sin_addr), ipbuf, ipbuf_len);
+ } else {
+ struct sockaddr_in6 *sa = (struct sockaddr_in6 *)info->ai_addr;
+ inet_ntop(AF_INET6, &(sa->sin6_addr), ipbuf, ipbuf_len);
+ }
+
+ freeaddrinfo(info);
+ return ANET_OK;
+}
+
+static int anetSetReuseAddr(char *err, int fd) {
+ int yes = 1;
+ /* Make sure connection-intensive things like the redis benchmark
+ * will be able to close/open sockets a zillion of times */
+ if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) == -1) {
+ anetSetError(err, "setsockopt SO_REUSEADDR: %s", strerror(errno));
+ return ANET_ERR;
+ }
+ return ANET_OK;
+}
+
+static int anetCreateSocket(char *err, int domain) {
+ int s;
+ if ((s = socket(domain, SOCK_STREAM, 0)) == -1) {
+ anetSetError(err, "creating socket: %s", strerror(errno));
+ return ANET_ERR;
+ }
+
+ /* Make sure connection-intensive things like the redis benchmark
+ * will be able to close/open sockets a zillion of times */
+ if (anetSetReuseAddr(err,s) == ANET_ERR) {
+ close(s);
+ return ANET_ERR;
+ }
+ return s;
+}
+
+#define ANET_CONNECT_NONE 0
+#define ANET_CONNECT_NONBLOCK 1
+#define ANET_CONNECT_BE_BINDING 2 /* Best effort binding. */
+static int anetTcpGenericConnect(char *err, const char *addr, int port,
+ const char *source_addr, int flags)
+{
+ int s = ANET_ERR, rv;
+ char portstr[6]; /* strlen("65535") + 1; */
+ struct addrinfo hints, *servinfo, *bservinfo, *p, *b;
+
+ snprintf(portstr,sizeof(portstr),"%d",port);
+ memset(&hints,0,sizeof(hints));
+ hints.ai_family = AF_UNSPEC;
+ hints.ai_socktype = SOCK_STREAM;
+
+ if ((rv = getaddrinfo(addr,portstr,&hints,&servinfo)) != 0) {
+ anetSetError(err, "%s", gai_strerror(rv));
+ return ANET_ERR;
+ }
+ for (p = servinfo; p != NULL; p = p->ai_next) {
+ /* Try to create the socket and to connect it.
+ * If we fail in the socket() call, or on connect(), we retry with
+ * the next entry in servinfo. */
+ if ((s = socket(p->ai_family,p->ai_socktype,p->ai_protocol)) == -1)
+ continue;
+ if (anetSetReuseAddr(err,s) == ANET_ERR) goto error;
+ if (flags & ANET_CONNECT_NONBLOCK && anetNonBlock(err,s) != ANET_OK)
+ goto error;
+ if (source_addr) {
+ int bound = 0;
+ /* Using getaddrinfo saves us from self-determining IPv4 vs IPv6 */
+ if ((rv = getaddrinfo(source_addr, NULL, &hints, &bservinfo)) != 0)
+ {
+ anetSetError(err, "%s", gai_strerror(rv));
+ goto error;
+ }
+ for (b = bservinfo; b != NULL; b = b->ai_next) {
+ if (bind(s,b->ai_addr,b->ai_addrlen) != -1) {
+ bound = 1;
+ break;
+ }
+ }
+ freeaddrinfo(bservinfo);
+ if (!bound) {
+ anetSetError(err, "bind: %s", strerror(errno));
+ goto error;
+ }
+ }
+ if (connect(s,p->ai_addr,p->ai_addrlen) == -1) {
+ /* If the socket is non-blocking, it is ok for connect() to
+ * return an EINPROGRESS error here. */
+ if (errno == EINPROGRESS && flags & ANET_CONNECT_NONBLOCK)
+ goto end;
+ close(s);
+ s = ANET_ERR;
+ continue;
+ }
+
+ /* If we ended an iteration of the for loop without errors, we
+ * have a connected socket. Let's return to the caller. */
+ goto end;
+ }
+ if (p == NULL)
+ anetSetError(err, "creating socket: %s", strerror(errno));
+
+error:
+ if (s != ANET_ERR) {
+ close(s);
+ s = ANET_ERR;
+ }
+
+end:
+ freeaddrinfo(servinfo);
+
+ /* Handle best effort binding: if a binding address was used, but it is
+ * not possible to create a socket, try again without a binding address. */
+ if (s == ANET_ERR && source_addr && (flags & ANET_CONNECT_BE_BINDING)) {
+ return anetTcpGenericConnect(err,addr,port,NULL,flags);
+ } else {
+ return s;
+ }
+}
+
+int anetTcpNonBlockConnect(char *err, const char *addr, int port)
+{
+ return anetTcpGenericConnect(err,addr,port,NULL,ANET_CONNECT_NONBLOCK);
+}
+
+int anetTcpNonBlockBestEffortBindConnect(char *err, const char *addr, int port,
+ const char *source_addr)
+{
+ return anetTcpGenericConnect(err,addr,port,source_addr,
+ ANET_CONNECT_NONBLOCK|ANET_CONNECT_BE_BINDING);
+}
+
+int anetUnixGenericConnect(char *err, const char *path, int flags)
+{
+ int s;
+ struct sockaddr_un sa;
+
+ if ((s = anetCreateSocket(err,AF_LOCAL)) == ANET_ERR)
+ return ANET_ERR;
+
+ sa.sun_family = AF_LOCAL;
+ strncpy(sa.sun_path,path,sizeof(sa.sun_path)-1);
+ if (flags & ANET_CONNECT_NONBLOCK) {
+ if (anetNonBlock(err,s) != ANET_OK) {
+ close(s);
+ return ANET_ERR;
+ }
+ }
+ if (connect(s,(struct sockaddr*)&sa,sizeof(sa)) == -1) {
+ if (errno == EINPROGRESS &&
+ flags & ANET_CONNECT_NONBLOCK)
+ return s;
+
+ anetSetError(err, "connect: %s", strerror(errno));
+ close(s);
+ return ANET_ERR;
+ }
+ return s;
+}
+
+static int anetListen(char *err, int s, struct sockaddr *sa, socklen_t len, int backlog, mode_t perm) {
+ if (bind(s,sa,len) == -1) {
+ anetSetError(err, "bind: %s", strerror(errno));
+ close(s);
+ return ANET_ERR;
+ }
+
+ if (sa->sa_family == AF_LOCAL && perm)
+ chmod(((struct sockaddr_un *) sa)->sun_path, perm);
+
+ if (listen(s, backlog) == -1) {
+ anetSetError(err, "listen: %s", strerror(errno));
+ close(s);
+ return ANET_ERR;
+ }
+ return ANET_OK;
+}
+
+static int anetV6Only(char *err, int s) {
+ int yes = 1;
+ if (setsockopt(s,IPPROTO_IPV6,IPV6_V6ONLY,&yes,sizeof(yes)) == -1) {
+ anetSetError(err, "setsockopt: %s", strerror(errno));
+ return ANET_ERR;
+ }
+ return ANET_OK;
+}
+
+static int _anetTcpServer(char *err, int port, char *bindaddr, int af, int backlog)
+{
+ int s = -1, rv;
+ char _port[6]; /* strlen("65535") */
+ struct addrinfo hints, *servinfo, *p;
+
+ snprintf(_port,6,"%d",port);
+ memset(&hints,0,sizeof(hints));
+ hints.ai_family = af;
+ hints.ai_socktype = SOCK_STREAM;
+ hints.ai_flags = AI_PASSIVE; /* No effect if bindaddr != NULL */
+ if (bindaddr && !strcmp("*", bindaddr))
+ bindaddr = NULL;
+ if (af == AF_INET6 && bindaddr && !strcmp("::*", bindaddr))
+ bindaddr = NULL;
+
+ if ((rv = getaddrinfo(bindaddr,_port,&hints,&servinfo)) != 0) {
+ anetSetError(err, "%s", gai_strerror(rv));
+ return ANET_ERR;
+ }
+ for (p = servinfo; p != NULL; p = p->ai_next) {
+ if ((s = socket(p->ai_family,p->ai_socktype,p->ai_protocol)) == -1)
+ continue;
+
+ if (af == AF_INET6 && anetV6Only(err,s) == ANET_ERR) goto error;
+ if (anetSetReuseAddr(err,s) == ANET_ERR) goto error;
+ if (anetListen(err,s,p->ai_addr,p->ai_addrlen,backlog,0) == ANET_ERR) s = ANET_ERR;
+ goto end;
+ }
+ if (p == NULL) {
+ anetSetError(err, "unable to bind socket, errno: %d", errno);
+ goto error;
+ }
+
+error:
+ if (s != -1) close(s);
+ s = ANET_ERR;
+end:
+ freeaddrinfo(servinfo);
+ return s;
+}
+
+int anetTcpServer(char *err, int port, char *bindaddr, int backlog)
+{
+ return _anetTcpServer(err, port, bindaddr, AF_INET, backlog);
+}
+
+int anetTcp6Server(char *err, int port, char *bindaddr, int backlog)
+{
+ return _anetTcpServer(err, port, bindaddr, AF_INET6, backlog);
+}
+
+int anetUnixServer(char *err, char *path, mode_t perm, int backlog)
+{
+ int s;
+ struct sockaddr_un sa;
+
+ if (strlen(path) > sizeof(sa.sun_path)-1) {
+ anetSetError(err,"unix socket path too long (%zu), must be under %zu", strlen(path), sizeof(sa.sun_path));
+ return ANET_ERR;
+ }
+ if ((s = anetCreateSocket(err,AF_LOCAL)) == ANET_ERR)
+ return ANET_ERR;
+
+ memset(&sa,0,sizeof(sa));
+ sa.sun_family = AF_LOCAL;
+ strncpy(sa.sun_path,path,sizeof(sa.sun_path)-1);
+ if (anetListen(err,s,(struct sockaddr*)&sa,sizeof(sa),backlog,perm) == ANET_ERR)
+ return ANET_ERR;
+ return s;
+}
+
+/* Accept a connection and also make sure the socket is non-blocking, and CLOEXEC.
+ * returns the new socket FD, or -1 on error. */
+static int anetGenericAccept(char *err, int s, struct sockaddr *sa, socklen_t *len) {
+ int fd;
+ do {
+ /* Use the accept4() call on linux to simultaneously accept and
+ * set a socket as non-blocking. */
+#ifdef HAVE_ACCEPT4
+ fd = accept4(s, sa, len, SOCK_NONBLOCK | SOCK_CLOEXEC);
+#else
+ fd = accept(s,sa,len);
+#endif
+ } while(fd == -1 && errno == EINTR);
+ if (fd == -1) {
+ anetSetError(err, "accept: %s", strerror(errno));
+ return ANET_ERR;
+ }
+#ifndef HAVE_ACCEPT4
+ if (anetCloexec(fd) == -1) {
+ anetSetError(err, "anetCloexec: %s", strerror(errno));
+ close(fd);
+ return ANET_ERR;
+ }
+ if (anetNonBlock(err, fd) != ANET_OK) {
+ close(fd);
+ return ANET_ERR;
+ }
+#endif
+ return fd;
+}
+
+/* Accept a connection and also make sure the socket is non-blocking, and CLOEXEC.
+ * returns the new socket FD, or -1 on error. */
+int anetTcpAccept(char *err, int serversock, char *ip, size_t ip_len, int *port) {
+ int fd;
+ struct sockaddr_storage sa;
+ socklen_t salen = sizeof(sa);
+ if ((fd = anetGenericAccept(err,serversock,(struct sockaddr*)&sa,&salen)) == ANET_ERR)
+ return ANET_ERR;
+
+ if (sa.ss_family == AF_INET) {
+ struct sockaddr_in *s = (struct sockaddr_in *)&sa;
+ if (ip) inet_ntop(AF_INET,(void*)&(s->sin_addr),ip,ip_len);
+ if (port) *port = ntohs(s->sin_port);
+ } else {
+ struct sockaddr_in6 *s = (struct sockaddr_in6 *)&sa;
+ if (ip) inet_ntop(AF_INET6,(void*)&(s->sin6_addr),ip,ip_len);
+ if (port) *port = ntohs(s->sin6_port);
+ }
+ return fd;
+}
+
+/* Accept a connection and also make sure the socket is non-blocking, and CLOEXEC.
+ * returns the new socket FD, or -1 on error. */
+int anetUnixAccept(char *err, int s) {
+ int fd;
+ struct sockaddr_un sa;
+ socklen_t salen = sizeof(sa);
+ if ((fd = anetGenericAccept(err,s,(struct sockaddr*)&sa,&salen)) == ANET_ERR)
+ return ANET_ERR;
+
+ return fd;
+}
+
+int anetFdToString(int fd, char *ip, size_t ip_len, int *port, int fd_to_str_type) {
+ struct sockaddr_storage sa;
+ socklen_t salen = sizeof(sa);
+
+ if (fd_to_str_type == FD_TO_PEER_NAME) {
+ if (getpeername(fd, (struct sockaddr *)&sa, &salen) == -1) goto error;
+ } else {
+ if (getsockname(fd, (struct sockaddr *)&sa, &salen) == -1) goto error;
+ }
+
+ if (sa.ss_family == AF_INET) {
+ struct sockaddr_in *s = (struct sockaddr_in *)&sa;
+ if (ip) {
+ if (inet_ntop(AF_INET,(void*)&(s->sin_addr),ip,ip_len) == NULL)
+ goto error;
+ }
+ if (port) *port = ntohs(s->sin_port);
+ } else if (sa.ss_family == AF_INET6) {
+ struct sockaddr_in6 *s = (struct sockaddr_in6 *)&sa;
+ if (ip) {
+ if (inet_ntop(AF_INET6,(void*)&(s->sin6_addr),ip,ip_len) == NULL)
+ goto error;
+ }
+ if (port) *port = ntohs(s->sin6_port);
+ } else if (sa.ss_family == AF_UNIX) {
+ if (ip) {
+ int res = snprintf(ip, ip_len, "/unixsocket");
+ if (res < 0 || (unsigned int) res >= ip_len) goto error;
+ }
+ if (port) *port = 0;
+ } else {
+ goto error;
+ }
+ return 0;
+
+error:
+ if (ip) {
+ if (ip_len >= 2) {
+ ip[0] = '?';
+ ip[1] = '\0';
+ } else if (ip_len == 1) {
+ ip[0] = '\0';
+ }
+ }
+ if (port) *port = 0;
+ return -1;
+}
+
+/* Format an IP,port pair into something easy to parse. If IP is IPv6
+ * (matches for ":"), the ip is surrounded by []. IP and port are just
+ * separated by colons. This the standard to display addresses within Redis. */
+int anetFormatAddr(char *buf, size_t buf_len, char *ip, int port) {
+ return snprintf(buf,buf_len, strchr(ip,':') ?
+ "[%s]:%d" : "%s:%d", ip, port);
+}
+
+/* Like anetFormatAddr() but extract ip and port from the socket's peer/sockname. */
+int anetFormatFdAddr(int fd, char *buf, size_t buf_len, int fd_to_str_type) {
+ char ip[INET6_ADDRSTRLEN];
+ int port;
+
+ anetFdToString(fd,ip,sizeof(ip),&port,fd_to_str_type);
+ return anetFormatAddr(buf, buf_len, ip, port);
+}
+
+/* Create a pipe buffer with given flags for read end and write end.
+ * Note that it supports the file flags defined by pipe2() and fcntl(F_SETFL),
+ * and one of the use cases is O_CLOEXEC|O_NONBLOCK. */
+int anetPipe(int fds[2], int read_flags, int write_flags) {
+ int pipe_flags = 0;
+#if defined(__linux__) || defined(__FreeBSD__)
+ /* When possible, try to leverage pipe2() to apply flags that are common to both ends.
+ * There is no harm to set O_CLOEXEC to prevent fd leaks. */
+ pipe_flags = O_CLOEXEC | (read_flags & write_flags);
+ if (pipe2(fds, pipe_flags)) {
+ /* Fail on real failures, and fallback to simple pipe if pipe2 is unsupported. */
+ if (errno != ENOSYS && errno != EINVAL)
+ return -1;
+ pipe_flags = 0;
+ } else {
+ /* If the flags on both ends are identical, no need to do anything else. */
+ if ((O_CLOEXEC | read_flags) == (O_CLOEXEC | write_flags))
+ return 0;
+ /* Clear the flags which have already been set using pipe2. */
+ read_flags &= ~pipe_flags;
+ write_flags &= ~pipe_flags;
+ }
+#endif
+
+ /* When we reach here with pipe_flags of 0, it means pipe2 failed (or was not attempted),
+ * so we try to use pipe. Otherwise, we skip and proceed to set specific flags below. */
+ if (pipe_flags == 0 && pipe(fds))
+ return -1;
+
+ /* File descriptor flags.
+ * Currently, only one such flag is defined: FD_CLOEXEC, the close-on-exec flag. */
+ if (read_flags & O_CLOEXEC)
+ if (fcntl(fds[0], F_SETFD, FD_CLOEXEC))
+ goto error;
+ if (write_flags & O_CLOEXEC)
+ if (fcntl(fds[1], F_SETFD, FD_CLOEXEC))
+ goto error;
+
+ /* File status flags after clearing the file descriptor flag O_CLOEXEC. */
+ read_flags &= ~O_CLOEXEC;
+ if (read_flags)
+ if (fcntl(fds[0], F_SETFL, read_flags))
+ goto error;
+ write_flags &= ~O_CLOEXEC;
+ if (write_flags)
+ if (fcntl(fds[1], F_SETFL, write_flags))
+ goto error;
+
+ return 0;
+
+error:
+ close(fds[0]);
+ close(fds[1]);
+ return -1;
+}
+
+int anetSetSockMarkId(char *err, int fd, uint32_t id) {
+#ifdef HAVE_SOCKOPTMARKID
+ if (setsockopt(fd, SOL_SOCKET, SOCKOPTMARKID, (void *)&id, sizeof(id)) == -1) {
+ anetSetError(err, "setsockopt: %s", strerror(errno));
+ return ANET_ERR;
+ }
+ return ANET_OK;
+#else
+ UNUSED(fd);
+ UNUSED(id);
+ anetSetError(err,"anetSetSockMarkid unsupported on this platform");
+ return ANET_OK;
+#endif
+}