/*
- * Copyright (c) 2008, 2009, 2010 Nicira Networks.
+ * Copyright (c) 2008, 2009, 2010, 2011, 2012 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
#include <config.h>
#include "socket-util.h"
#include <arpa/inet.h>
+#include <assert.h>
#include <errno.h>
#include <fcntl.h>
+#include <net/if.h>
#include <netdb.h>
#include <poll.h>
#include <stddef.h>
#include <sys/stat.h>
#include <sys/un.h>
#include <unistd.h>
+#include "dynamic-string.h"
#include "fatal-signal.h"
+#include "packets.h"
#include "util.h"
#include "vlog.h"
+#if AF_PACKET && __linux__
+#include <linux/if_packet.h>
+#endif
+#ifdef HAVE_NETLINK
+#include "netlink-protocol.h"
+#include "netlink-socket.h"
+#endif
VLOG_DEFINE_THIS_MODULE(socket_util);
#define LINUX 0
#endif
+#ifndef O_DIRECTORY
+#define O_DIRECTORY 0
+#endif
+
+static int getsockopt_int(int fd, int level, int option, const char *optname,
+ int *valuep);
+
/* Sets 'fd' to non-blocking mode. Returns 0 if successful, otherwise a
* positive errno value. */
int
}
}
+static int
+set_dscp(int fd, uint8_t dscp)
+{
+ if (dscp > 63) {
+ return EINVAL;
+ }
+
+ dscp = dscp << 2;
+ if (setsockopt(fd, IPPROTO_IP, IP_TOS, &dscp, sizeof dscp)) {
+ return errno;
+ }
+
+ return 0;
+}
+
static bool
rlim_is_finite(rlim_t limit)
{
lookup_ip(const char *host_name, struct in_addr *addr)
{
if (!inet_aton(host_name, addr)) {
- struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
+ static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
VLOG_ERR_RL(&rl, "\"%s\" is not a valid IP address", host_name);
return ENOENT;
}
return 0;
}
+/* Translates 'host_name', which must be a string representation of an IPv6
+ * address, into a numeric IPv6 address in '*addr'. Returns 0 if successful,
+ * otherwise a positive errno value. */
+int
+lookup_ipv6(const char *host_name, struct in6_addr *addr)
+{
+ if (inet_pton(AF_INET6, host_name, addr) != 1) {
+ static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
+ VLOG_ERR_RL(&rl, "\"%s\" is not a valid IPv6 address", host_name);
+ return ENOENT;
+ }
+ return 0;
+}
+
+/* Translates 'host_name', which must be a host name or a string representation
+ * of an IP address, into a numeric IP address in '*addr'. Returns 0 if
+ * successful, otherwise a positive errno value.
+ *
+ * Most Open vSwitch code should not use this because it causes deadlocks:
+ * gethostbyname() sends out a DNS request but that starts a new flow for which
+ * OVS must set up a flow, but it can't because it's waiting for a DNS reply.
+ * The synchronous lookup also delays other activty. (Of course we can solve
+ * this but it doesn't seem worthwhile quite yet.) */
+int
+lookup_hostname(const char *host_name, struct in_addr *addr)
+{
+ struct hostent *h;
+
+ if (inet_aton(host_name, addr)) {
+ return 0;
+ }
+
+ h = gethostbyname(host_name);
+ if (h) {
+ *addr = *(struct in_addr *) h->h_addr;
+ return 0;
+ }
+
+ return (h_errno == HOST_NOT_FOUND ? ENOENT
+ : h_errno == TRY_AGAIN ? EAGAIN
+ : h_errno == NO_RECOVERY ? EIO
+ : h_errno == NO_ADDRESS ? ENXIO
+ : EINVAL);
+}
+
/* Returns the error condition associated with socket 'fd' and resets the
* socket's error status. */
int
get_socket_error(int fd)
{
int error;
- socklen_t len = sizeof(error);
- if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &error, &len) < 0) {
- struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 10);
+
+ if (getsockopt_int(fd, SOL_SOCKET, SO_ERROR, "SO_ERROR", &error)) {
error = errno;
- VLOG_ERR_RL(&rl, "getsockopt(SO_ERROR): %s", strerror(error));
}
return error;
}
int
drain_rcvbuf(int fd)
{
- socklen_t rcvbuf_len;
- size_t rcvbuf;
+ int rcvbuf;
- rcvbuf_len = sizeof rcvbuf;
- if (getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &rcvbuf, &rcvbuf_len) < 0) {
- static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 10);
- VLOG_ERR_RL(&rl, "getsockopt(SO_RCVBUF) failed: %s", strerror(errno));
- return errno;
+ rcvbuf = get_socket_rcvbuf(fd);
+ if (rcvbuf < 0) {
+ return -rcvbuf;
}
+
while (rcvbuf > 0) {
/* In Linux, specifying MSG_TRUNC in the flags argument causes the
* datagram length to be returned, even if that is longer than the
return 0;
}
+/* Returns the size of socket 'sock''s receive buffer (SO_RCVBUF), or a
+ * negative errno value if an error occurs. */
+int
+get_socket_rcvbuf(int sock)
+{
+ int rcvbuf;
+ int error;
+
+ error = getsockopt_int(sock, SOL_SOCKET, SO_RCVBUF, "SO_RCVBUF", &rcvbuf);
+ return error ? -error : rcvbuf;
+}
+
/* Reads and discards up to 'n' datagrams from 'fd', stopping as soon as no
* more data can be immediately read. ('fd' should therefore be in
* non-blocking mode.)*/
/* Stores in '*un' a sockaddr_un that refers to file 'name'. Stores in
* '*un_len' the size of the sockaddr_un. */
static void
-make_sockaddr_un(const char *name, struct sockaddr_un* un, socklen_t *un_len)
+make_sockaddr_un__(const char *name, struct sockaddr_un *un, socklen_t *un_len)
{
un->sun_family = AF_UNIX;
- strncpy(un->sun_path, name, sizeof un->sun_path);
- un->sun_path[sizeof un->sun_path - 1] = '\0';
+ ovs_strzcpy(un->sun_path, name, sizeof un->sun_path);
*un_len = (offsetof(struct sockaddr_un, sun_path)
+ strlen (un->sun_path) + 1);
}
+/* Stores in '*un' a sockaddr_un that refers to file 'name'. Stores in
+ * '*un_len' the size of the sockaddr_un.
+ *
+ * Returns 0 on success, otherwise a positive errno value. On success,
+ * '*dirfdp' is either -1 or a nonnegative file descriptor that the caller
+ * should close after using '*un' to bind or connect. On failure, '*dirfdp' is
+ * -1. */
+static int
+make_sockaddr_un(const char *name, struct sockaddr_un *un, socklen_t *un_len,
+ int *dirfdp)
+{
+ enum { MAX_UN_LEN = sizeof un->sun_path - 1 };
+
+ *dirfdp = -1;
+ if (strlen(name) > MAX_UN_LEN) {
+ static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1);
+
+ if (LINUX) {
+ /* 'name' is too long to fit in a sockaddr_un, but we have a
+ * workaround for that on Linux: shorten it by opening a file
+ * descriptor for the directory part of the name and indirecting
+ * through /proc/self/fd/<dirfd>/<basename>. */
+ char *dir, *base;
+ char *short_name;
+ int dirfd;
+
+ dir = dir_name(name);
+ base = base_name(name);
+
+ dirfd = open(dir, O_DIRECTORY | O_RDONLY);
+ if (dirfd < 0) {
+ free(base);
+ free(dir);
+ return errno;
+ }
+
+ short_name = xasprintf("/proc/self/fd/%d/%s", dirfd, base);
+ free(dir);
+ free(base);
+
+ if (strlen(short_name) <= MAX_UN_LEN) {
+ make_sockaddr_un__(short_name, un, un_len);
+ free(short_name);
+ *dirfdp = dirfd;
+ return 0;
+ }
+ free(short_name);
+ close(dirfd);
+
+ VLOG_WARN_RL(&rl, "Unix socket name %s is longer than maximum "
+ "%d bytes (even shortened)", name, MAX_UN_LEN);
+ } else {
+ /* 'name' is too long and we have no workaround. */
+ VLOG_WARN_RL(&rl, "Unix socket name %s is longer than maximum "
+ "%d bytes", name, MAX_UN_LEN);
+ }
+
+ return ENAMETOOLONG;
+ } else {
+ make_sockaddr_un__(name, un, un_len);
+ return 0;
+ }
+}
+
+/* Binds Unix domain socket 'fd' to a file with permissions 0700. */
+static int
+bind_unix_socket(int fd, struct sockaddr *sun, socklen_t sun_len)
+{
+ /* According to _Unix Network Programming_, umask should affect bind(). */
+ mode_t old_umask = umask(0077);
+ int error = bind(fd, sun, sun_len) ? errno : 0;
+ umask(old_umask);
+ return error;
+}
+
/* Creates a Unix domain socket in the given 'style' (either SOCK_DGRAM or
* SOCK_STREAM) that is bound to '*bind_path' (if 'bind_path' is non-null) and
* connected to '*connect_path' (if 'connect_path' is non-null). If 'nonblock'
if (nonblock) {
int flags = fcntl(fd, F_GETFL, 0);
if (flags == -1) {
+ error = errno;
goto error;
}
if (fcntl(fd, F_SETFL, flags | O_NONBLOCK) == -1) {
+ error = errno;
goto error;
}
}
if (bind_path) {
struct sockaddr_un un;
socklen_t un_len;
- make_sockaddr_un(bind_path, &un, &un_len);
- if (unlink(un.sun_path) && errno != ENOENT) {
- VLOG_WARN("unlinking \"%s\": %s\n", un.sun_path, strerror(errno));
+ int dirfd;
+
+ if (unlink(bind_path) && errno != ENOENT) {
+ VLOG_WARN("unlinking \"%s\": %s\n", bind_path, strerror(errno));
}
fatal_signal_add_file_to_unlink(bind_path);
- if (bind(fd, (struct sockaddr*) &un, un_len)
- || fchmod(fd, S_IRWXU)) {
+
+ error = make_sockaddr_un(bind_path, &un, &un_len, &dirfd);
+ if (!error) {
+ error = bind_unix_socket(fd, (struct sockaddr *) &un, un_len);
+ }
+ if (dirfd >= 0) {
+ close(dirfd);
+ }
+ if (error) {
goto error;
}
}
if (connect_path) {
struct sockaddr_un un;
socklen_t un_len;
- make_sockaddr_un(connect_path, &un, &un_len);
- if (connect(fd, (struct sockaddr*) &un, un_len)
+ int dirfd;
+
+ error = make_sockaddr_un(connect_path, &un, &un_len, &dirfd);
+ if (!error
+ && connect(fd, (struct sockaddr*) &un, un_len)
&& errno != EINPROGRESS) {
+ error = errno;
+ }
+ if (dirfd >= 0) {
+ close(dirfd);
+ }
+ if (error) {
goto error;
}
}
if (passcred) {
int enable = 1;
if (setsockopt(fd, SOL_SOCKET, SO_PASSCRED, &enable, sizeof(enable))) {
+ error = errno;
goto error;
}
}
return fd;
error:
- error = errno == EAGAIN ? EPROTO : errno;
+ if (error == EAGAIN) {
+ error = EPROTO;
+ }
if (bind_path) {
- fatal_signal_remove_file_to_unlink(bind_path);
+ fatal_signal_unlink_file_now(bind_path);
}
close(fd);
return -error;
: 0);
}
-uint32_t
-guess_netmask(uint32_t ip)
+ovs_be32
+guess_netmask(ovs_be32 ip_)
{
- ip = ntohl(ip);
+ uint32_t ip = ntohl(ip_);
return ((ip >> 31) == 0 ? htonl(0xff000000) /* Class A */
: (ip >> 30) == 2 ? htonl(0xffff0000) /* Class B */
: (ip >> 29) == 6 ? htonl(0xffffff00) /* Class C */
* and stores -1 into '*fdp'.
*
* If 'sinp' is non-null, then on success the target address is stored into
- * '*sinp'. */
+ * '*sinp'.
+ *
+ * 'dscp' becomes the DSCP bits in the IP headers for the new connection. It
+ * should be in the range [0, 63] and will automatically be shifted to the
+ * appropriately place in the IP tos field. */
int
inet_open_active(int style, const char *target, uint16_t default_port,
- struct sockaddr_in *sinp, int *fdp)
+ struct sockaddr_in *sinp, int *fdp, uint8_t dscp)
{
struct sockaddr_in sin;
int fd = -1;
}
error = set_nonblocking(fd);
if (error) {
- goto exit_close;
+ goto exit;
+ }
+
+ /* The dscp bits must be configured before connect() to ensure that the TOS
+ * field is set during the connection establishment. If set after
+ * connect(), the handshake SYN frames will be sent with a TOS of 0. */
+ error = set_dscp(fd, dscp);
+ if (error) {
+ VLOG_ERR("%s: socket: %s", target, strerror(error));
+ goto exit;
}
/* Connect. */
error = connect(fd, (struct sockaddr *) &sin, sizeof sin) == 0 ? 0 : errno;
if (error == EINPROGRESS) {
error = EAGAIN;
- } else if (error && error != EAGAIN) {
- goto exit_close;
}
- /* Success: error is 0 or EAGAIN. */
- goto exit;
-
-exit_close:
- close(fd);
exit:
if (!error || error == EAGAIN) {
if (sinp) {
*sinp = sin;
}
- *fdp = fd;
- } else {
- *fdp = -1;
+ } else if (fd >= 0) {
+ close(fd);
}
+ *fdp = fd;
return error;
}
-/* Opens a non-blocking IPv4 socket of the specified 'style', binds to
- * 'target', and listens for incoming connections. 'target' should be a string
- * in the format "[<port>][:<ip>]":
+/* Parses 'target', which should be a string in the format "[<port>][:<ip>]":
*
* - If 'default_port' is -1, then <port> is required. Otherwise, if
* <port> is omitted, then 'default_port' is used instead.
*
* - If <ip> is omitted then the IP address is wildcarded.
*
- * 'style' should be SOCK_STREAM (for TCP) or SOCK_DGRAM (for UDP).
- *
- * For TCP, the socket will have SO_REUSEADDR turned on.
- *
- * On success, returns a non-negative file descriptor. On failure, returns a
- * negative errno value.
- *
- * If 'sinp' is non-null, then on success the bound address is stored into
- * '*sinp'. */
-int
-inet_open_passive(int style, const char *target_, int default_port,
- struct sockaddr_in *sinp)
+ * If successful, stores the address into '*sinp' and returns true; otherwise
+ * zeros '*sinp' and returns false. */
+bool
+inet_parse_passive(const char *target_, int default_port,
+ struct sockaddr_in *sinp)
{
char *target = xstrdup(target_);
char *string_ptr = target;
- struct sockaddr_in sin;
const char *host_name;
const char *port_string;
- int fd = 0, error, port;
- unsigned int yes = 1;
+ bool ok = false;
+ int port;
/* Address defaults. */
- memset(&sin, 0, sizeof sin);
- sin.sin_family = AF_INET;
- sin.sin_addr.s_addr = htonl(INADDR_ANY);
- sin.sin_port = htons(default_port);
+ memset(sinp, 0, sizeof *sinp);
+ sinp->sin_family = AF_INET;
+ sinp->sin_addr.s_addr = htonl(INADDR_ANY);
+ sinp->sin_port = htons(default_port);
/* Parse optional port number. */
port_string = strsep(&string_ptr, ":");
if (port_string && str_to_int(port_string, 10, &port)) {
- sin.sin_port = htons(port);
+ sinp->sin_port = htons(port);
} else if (default_port < 0) {
VLOG_ERR("%s: port number must be specified", target_);
- error = EAFNOSUPPORT;
goto exit;
}
/* Parse optional bind IP. */
host_name = strsep(&string_ptr, ":");
- if (host_name && host_name[0]) {
- error = lookup_ip(host_name, &sin.sin_addr);
- if (error) {
- goto exit;
- }
+ if (host_name && host_name[0] && lookup_ip(host_name, &sinp->sin_addr)) {
+ goto exit;
+ }
+
+ ok = true;
+
+exit:
+ if (!ok) {
+ memset(sinp, 0, sizeof *sinp);
+ }
+ free(target);
+ return ok;
+}
+
+
+/* Opens a non-blocking IPv4 socket of the specified 'style', binds to
+ * 'target', and listens for incoming connections. Parses 'target' in the same
+ * way was inet_parse_passive().
+ *
+ * 'style' should be SOCK_STREAM (for TCP) or SOCK_DGRAM (for UDP).
+ *
+ * For TCP, the socket will have SO_REUSEADDR turned on.
+ *
+ * On success, returns a non-negative file descriptor. On failure, returns a
+ * negative errno value.
+ *
+ * If 'sinp' is non-null, then on success the bound address is stored into
+ * '*sinp'.
+ *
+ * 'dscp' becomes the DSCP bits in the IP headers for the new connection. It
+ * should be in the range [0, 63] and will automatically be shifted to the
+ * appropriately place in the IP tos field. */
+int
+inet_open_passive(int style, const char *target, int default_port,
+ struct sockaddr_in *sinp, uint8_t dscp)
+{
+ struct sockaddr_in sin;
+ int fd = 0, error;
+ unsigned int yes = 1;
+
+ if (!inet_parse_passive(target, default_port, &sin)) {
+ return -EAFNOSUPPORT;
}
/* Create non-blocking socket, set SO_REUSEADDR. */
fd = socket(AF_INET, style, 0);
if (fd < 0) {
error = errno;
- VLOG_ERR("%s: socket: %s", target_, strerror(error));
- goto exit;
+ VLOG_ERR("%s: socket: %s", target, strerror(error));
+ return -error;
}
error = set_nonblocking(fd);
if (error) {
- goto exit_close;
+ goto error;
}
if (style == SOCK_STREAM
&& setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof yes) < 0) {
error = errno;
- VLOG_ERR("%s: setsockopt(SO_REUSEADDR): %s", target_, strerror(error));
- goto exit_close;
+ VLOG_ERR("%s: setsockopt(SO_REUSEADDR): %s", target, strerror(error));
+ goto error;
}
/* Bind. */
if (bind(fd, (struct sockaddr *) &sin, sizeof sin) < 0) {
error = errno;
- VLOG_ERR("%s: bind: %s", target_, strerror(error));
- goto exit_close;
+ VLOG_ERR("%s: bind: %s", target, strerror(error));
+ goto error;
+ }
+
+ /* The dscp bits must be configured before connect() to ensure that the TOS
+ * field is set during the connection establishment. If set after
+ * connect(), the handshake SYN frames will be sent with a TOS of 0. */
+ error = set_dscp(fd, dscp);
+ if (error) {
+ VLOG_ERR("%s: socket: %s", target, strerror(error));
+ goto error;
}
/* Listen. */
- if (listen(fd, 10) < 0) {
+ if (style == SOCK_STREAM && listen(fd, 10) < 0) {
error = errno;
- VLOG_ERR("%s: listen: %s", target_, strerror(error));
- goto exit_close;
+ VLOG_ERR("%s: listen: %s", target, strerror(error));
+ goto error;
}
if (sinp) {
socklen_t sin_len = sizeof sin;
if (getsockname(fd, (struct sockaddr *) &sin, &sin_len) < 0){
error = errno;
- VLOG_ERR("%s: getsockname: %s", target_, strerror(error));
- goto exit_close;
+ VLOG_ERR("%s: getsockname: %s", target, strerror(error));
+ goto error;
}
if (sin.sin_family != AF_INET || sin_len != sizeof sin) {
- VLOG_ERR("%s: getsockname: invalid socket name", target_);
- goto exit_close;
+ error = EAFNOSUPPORT;
+ VLOG_ERR("%s: getsockname: invalid socket name", target);
+ goto error;
}
*sinp = sin;
}
- error = 0;
- goto exit;
+ return fd;
-exit_close:
+error:
close(fd);
-exit:
- free(target);
- return error ? -error : fd;
+ return -error;
}
/* Returns a readable and writable fd for /dev/null, if successful, otherwise
}
}
+void
+xpipe(int fds[2])
+{
+ if (pipe(fds)) {
+ VLOG_FATAL("failed to create pipe (%s)", strerror(errno));
+ }
+}
+
+static int
+getsockopt_int(int fd, int level, int option, const char *optname, int *valuep)
+{
+ static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 10);
+ socklen_t len;
+ int value;
+ int error;
+
+ len = sizeof value;
+ if (getsockopt(fd, level, option, &value, &len)) {
+ error = errno;
+ VLOG_ERR_RL(&rl, "getsockopt(%s): %s", optname, strerror(error));
+ } else if (len != sizeof value) {
+ error = EINVAL;
+ VLOG_ERR_RL(&rl, "getsockopt(%s): value is %u bytes (expected %zu)",
+ optname, (unsigned int) len, sizeof value);
+ } else {
+ error = 0;
+ }
+
+ *valuep = error ? 0 : value;
+ return error;
+}
+
+static void
+describe_sockaddr(struct ds *string, int fd,
+ int (*getaddr)(int, struct sockaddr *, socklen_t *))
+{
+ struct sockaddr_storage ss;
+ socklen_t len = sizeof ss;
+
+ if (!getaddr(fd, (struct sockaddr *) &ss, &len)) {
+ if (ss.ss_family == AF_INET) {
+ struct sockaddr_in sin;
+
+ memcpy(&sin, &ss, sizeof sin);
+ ds_put_format(string, IP_FMT":%"PRIu16,
+ IP_ARGS(&sin.sin_addr.s_addr), ntohs(sin.sin_port));
+ } else if (ss.ss_family == AF_UNIX) {
+ struct sockaddr_un sun;
+ const char *null;
+ size_t maxlen;
+
+ memcpy(&sun, &ss, sizeof sun);
+ maxlen = len - offsetof(struct sockaddr_un, sun_path);
+ null = memchr(sun.sun_path, '\0', maxlen);
+ ds_put_buffer(string, sun.sun_path,
+ null ? null - sun.sun_path : maxlen);
+ }
+#ifdef HAVE_NETLINK
+ else if (ss.ss_family == AF_NETLINK) {
+ int protocol;
+
+/* SO_PROTOCOL was introduced in 2.6.32. Support it regardless of the version
+ * of the Linux kernel headers in use at build time. */
+#ifndef SO_PROTOCOL
+#define SO_PROTOCOL 38
+#endif
+
+ if (!getsockopt_int(fd, SOL_SOCKET, SO_PROTOCOL, "SO_PROTOCOL",
+ &protocol)) {
+ switch (protocol) {
+ case NETLINK_ROUTE:
+ ds_put_cstr(string, "NETLINK_ROUTE");
+ break;
+
+ case NETLINK_GENERIC:
+ ds_put_cstr(string, "NETLINK_GENERIC");
+ break;
+
+ default:
+ ds_put_format(string, "AF_NETLINK family %d", protocol);
+ break;
+ }
+ } else {
+ ds_put_cstr(string, "AF_NETLINK");
+ }
+ }
+#endif
+#if AF_PACKET && __linux__
+ else if (ss.ss_family == AF_PACKET) {
+ struct sockaddr_ll sll;
+
+ memcpy(&sll, &ss, sizeof sll);
+ ds_put_cstr(string, "AF_PACKET");
+ if (sll.sll_ifindex) {
+ char name[IFNAMSIZ];
+
+ if (if_indextoname(sll.sll_ifindex, name)) {
+ ds_put_format(string, "(%s)", name);
+ } else {
+ ds_put_format(string, "(ifindex=%d)", sll.sll_ifindex);
+ }
+ }
+ if (sll.sll_protocol) {
+ ds_put_format(string, "(protocol=0x%"PRIu16")",
+ ntohs(sll.sll_protocol));
+ }
+ }
+#endif
+ else if (ss.ss_family == AF_UNSPEC) {
+ ds_put_cstr(string, "AF_UNSPEC");
+ } else {
+ ds_put_format(string, "AF_%d", (int) ss.ss_family);
+ }
+ }
+}
+
+
+#ifdef __linux__
+static void
+put_fd_filename(struct ds *string, int fd)
+{
+ char buf[1024];
+ char *linkname;
+ int n;
+
+ linkname = xasprintf("/proc/self/fd/%d", fd);
+ n = readlink(linkname, buf, sizeof buf);
+ if (n > 0) {
+ ds_put_char(string, ' ');
+ ds_put_buffer(string, buf, n);
+ if (n > sizeof buf) {
+ ds_put_cstr(string, "...");
+ }
+ }
+ free(linkname);
+}
+#endif
+
+/* Returns a malloc()'d string describing 'fd', for use in logging. */
+char *
+describe_fd(int fd)
+{
+ struct ds string;
+ struct stat s;
+
+ ds_init(&string);
+ if (fstat(fd, &s)) {
+ ds_put_format(&string, "fstat failed (%s)", strerror(errno));
+ } else if (S_ISSOCK(s.st_mode)) {
+ describe_sockaddr(&string, fd, getsockname);
+ ds_put_cstr(&string, "<->");
+ describe_sockaddr(&string, fd, getpeername);
+ } else {
+ ds_put_cstr(&string, (isatty(fd) ? "tty"
+ : S_ISDIR(s.st_mode) ? "directory"
+ : S_ISCHR(s.st_mode) ? "character device"
+ : S_ISBLK(s.st_mode) ? "block device"
+ : S_ISREG(s.st_mode) ? "file"
+ : S_ISFIFO(s.st_mode) ? "FIFO"
+ : S_ISLNK(s.st_mode) ? "symbolic link"
+ : "unknown"));
+#ifdef __linux__
+ put_fd_filename(&string, fd);
+#endif
+ }
+ return ds_steal_cstr(&string);
+}
git://git.onelab.eu / sliver-openvswitch.git / blobdiff