X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Fcompat%2Fsocket.h;h=3690ba6797c7c0c811a62ea4d1541eef0263e571;hp=5a6802aacd77720f72e7de93dfd4aeac61161b25;hb=de559cf1823ecaf083c7c827c926b3aece32df71;hpb=11a2fd460f033afa2d5f41a70eb1fd3a84fcf89d

diff --git a/src/common/compat/socket.h b/src/common/compat/socket.h
index 5a6802aac..3690ba679 100644
--- a/src/common/compat/socket.h
+++ b/src/common/compat/socket.h
@@ -1,18 +1,8 @@
 /*
- * Copyright (C) 2011 - David Goulet <dgoulet@efficios.com>
+ * Copyright (C) 2011 David Goulet <dgoulet@efficios.com>
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License, version 2 only,
- * as published by the Free Software Foundation.
+ * SPDX-License-Identifier: GPL-2.0-only
  *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
 #ifndef _COMPAT_SOCKET_H
@@ -23,6 +13,91 @@
 
 #include <common/macros.h>
 
+#ifndef MSG_NOSIGNAL
+# ifdef SO_NOSIGPIPE
+#   define MSG_NOSIGNAL SO_NOSIGPIPE
+# endif
+#endif
+
+#if defined(MSG_NOSIGNAL)
+static inline
+ssize_t lttng_recvmsg_nosigpipe(int sockfd, struct msghdr *msg)
+{
+	return recvmsg(sockfd, msg, MSG_NOSIGNAL);
+}
+#else
+
+#include <signal.h>
+#include <errno.h>
+
+static inline
+ssize_t lttng_recvmsg_nosigpipe(int sockfd, struct msghdr *msg)
+{
+	ssize_t received;
+	int saved_err;
+	sigset_t sigpipe_set, pending_set, old_set;
+	int sigpipe_was_pending;
+
+	/*
+	 * Discard the SIGPIPE from send(), not disturbing any SIGPIPE
+	 * that might be already pending. If a bogus SIGPIPE is sent to
+	 * the entire process concurrently by a malicious user, it may
+	 * be simply discarded.
+	 */
+	if (sigemptyset(&pending_set)) {
+		return -1;
+	}
+	/*
+	 * sigpending returns the mask of signals that are _both_
+	 * blocked for the thread _and_ pending for either the thread or
+	 * the entire process.
+	 */
+	if (sigpending(&pending_set)) {
+		return -1;
+	}
+	sigpipe_was_pending = sigismember(&pending_set, SIGPIPE);
+	/*
+	 * If sigpipe was pending, it means it was already blocked, so
+	 * no need to block it.
+	 */
+	if (!sigpipe_was_pending) {
+		if (sigemptyset(&sigpipe_set)) {
+			return -1;
+		}
+		if (sigaddset(&sigpipe_set, SIGPIPE)) {
+			return -1;
+		}
+		if (pthread_sigmask(SIG_BLOCK, &sigpipe_set, &old_set)) {
+			return -1;
+		}
+	}
+
+	/* Send and save errno. */
+	received = recvmsg(sockfd, msg, 0);
+	saved_err = errno;
+
+	if (received == -1 && errno == EPIPE && !sigpipe_was_pending) {
+		struct timespec timeout = { 0, 0 };
+		int ret;
+
+		do {
+			ret = sigtimedwait(&sigpipe_set, NULL,
+				&timeout);
+		} while (ret == -1 && errno == EINTR);
+	}
+	if (!sigpipe_was_pending) {
+		if (pthread_sigmask(SIG_SETMASK, &old_set, NULL)) {
+			return -1;
+		}
+	}
+	/* Restore send() errno */
+	errno = saved_err;
+
+	return received;
+}
+#endif
+
+
 #ifdef __linux__
 
 #define LTTNG_SOCK_CREDS SCM_CREDENTIALS
@@ -37,7 +112,7 @@ typedef struct ucred lttng_sock_cred;
 #define LTTNG_SOCK_GET_GID_CRED(c) LTTNG_REF(c)->gid
 #define LTTNG_SOCK_GET_PID_CRED(c) LTTNG_REF(c)->pid
 
-#elif (defined(__FreeBSD__) || defined(__CYGWIN__) || defined(__sun__))
+#elif (defined(__FreeBSD__) || defined(__CYGWIN__) || defined(__sun__) || defined(__APPLE__))
 
 struct lttng_sock_cred {
 	uid_t uid;
@@ -46,6 +121,10 @@ struct lttng_sock_cred {
 
 typedef struct lttng_sock_cred lttng_sock_cred;
 
+#define LTTNG_SOCK_SET_UID_CRED(c, u) LTTNG_REF(c)->uid = u
+#define LTTNG_SOCK_SET_GID_CRED(c, g) LTTNG_REF(c)->gid = g
+#define LTTNG_SOCK_SET_PID_CRED(c, p)
+
 #define LTTNG_SOCK_GET_UID_CRED(c) LTTNG_REF(c)->uid
 #define LTTNG_SOCK_GET_GID_CRED(c) LTTNG_REF(c)->gid
 #define LTTNG_SOCK_GET_PID_CRED(c) -1