Unfinished work on fseventsd - will be finished after Linux 5.7 is released

CMakeLists.txt

@@ -79,6 +79,7 @@ option(DEBIAN_PACKAGING "Packaging for Debian" OFF)
 option(ENABLE_TESTS "Install in-prefix unit tests" OFF)
 
 FindDsymutil()
+find_package(Setcap REQUIRED)
 
 # Missing CMakeLists.txt must trigger an error
 cmake_policy(SET CMP0014 NEW)

src/external/lkm

@@ -1 +1 @@
-Subproject commit d2e68bab6efa2ba827824aba48fb6e8c43e32126
+Subproject commit cd9430c6bd246b78a1a8201294335fcd858a4a9a

src/frameworks/CoreServices/src/FSEvents/CMakeLists.txt

@@ -13,3 +13,9 @@ add_framework(FSEvents
 		Foundation
 		system
 )
+
+add_darling_executable(fseventsd fseventsd.m)
+target_link_libraries(fseventsd system Foundation CarbonCore)
+
+install(TARGETS fseventsd DESTINATION libexec/darling/usr/sbin)
+install(CODE "execute_process(COMMAND ${SETCAP_EXECUTABLE} \"cap_sys_admin+ep\" \"${CMAKE_INSTALL_PREFIX}/libexec/darling/usr/sbin/fseventsd\")")

src/frameworks/CoreServices/src/FSEvents/fseventsd.h

@@ -0,0 +1,38 @@
+/*
+ This file is part of Darling.
+
+ Copyright (C) 2020 Lubos Dolezel
+
+ Darling is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ Darling 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 Darling.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef FSEVENTSD_H_
+#define FSEVENTSD_H_
+
+#define FSEVENTSD_SOCKET_PATH "/var/run/fseventsd.sock"
+
+typedef struct fseventsd_monitor {
+	int id;
+	char path[4096];
+	int flags;
+} fseventsd_monitor_t;
+
+typedef struct fseventsd_event {
+	int id;
+	char path[4096];
+	int flags;
+} fseventsd_event_t;
+
+#endif
+

src/frameworks/CoreServices/src/FSEvents/fseventsd.m

@@ -0,0 +1,194 @@
+/*
+ This file is part of Darling.
+
+ Copyright (C) 2020 Lubos Dolezel
+
+ Darling is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ Darling 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 Darling.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <ext/fanotify.h>
+#include <ext/file_handle.h>
+#include <linux/fanotify.h>
+#include <dispatch/dispatch.h>
+#include <CoreServices/FileManager.h>
+#import <Foundation/NSObjCRuntime.h>
+#import <Foundation/NSDictionary.h>
+#include "fseventsd.h"
+
+int g_listenSocket, g_fanotify;
+
+void setupListenSocket(void);
+void handleNewConnection(int fd);
+void setupFANotify(void);
+
+int main()
+{
+	setupListenSocket();
+	setupFANotify();
+
+	dispatch_main();
+	return 0;
+}
+
+void setupListenSocket(void)
+{
+	struct sockaddr_un sa;
+	sa.sun_family = AF_UNIX;
+
+	strcpy(sa.sun_path, FSEVENTSD_SOCKET_PATH);
+	unlink(FSEVENTSD_SOCKET_PATH);
+
+	g_listenSocket = socket(AF_UNIX, SOCK_SEQPACKET, 0);
+	if (g_listenSocket == -1)
+	{
+		perror("bind");
+		exit(EXIT_FAILURE);
+	}
+
+	int rv = bind(g_listenSocket, (const struct sockaddr *) &sa, sizeof(sa));
+	if (rv == -1)
+	{
+		perror("bind");
+		exit(EXIT_FAILURE);
+	}
+
+	rv = listen(g_listenSocket, 5);
+	if (rv == -1)
+	{
+		perror("listen");
+		exit(EXIT_FAILURE);
+	}
+
+	dispatch_source_t listenerSource = dispatch_source_create(DISPATCH_SOURCE_TYPE_READ, g_listenSocket, 0, dispatch_get_main_queue());
+	dispatch_source_set_event_handler(listenerSource, ^{
+		struct sockaddr_un sa;
+		sa.sun_family = AF_UNIX;
+
+		socklen_t len = sizeof(sa);
+
+		int rv = accept(g_listenSocket, (struct sockaddr*) &sa, &len);
+		if (rv >= 0)
+			handleNewConnection(rv);
+	});
+	dispatch_resume(listenerSource);
+}
+
+void handleClientCommand(int fd, const fseventsd_monitor_t* cmd)
+{
+
+}
+
+void handleNewConnection(int fd)
+{
+	dispatch_source_t socketSource = dispatch_source_create(DISPATCH_SOURCE_TYPE_READ, fd, 0, dispatch_get_main_queue());
+
+	dispatch_source_set_event_handler(socketSource, ^{
+		fseventsd_monitor_t cmd;
+		struct msghdr msg;
+		struct iovec iov = {
+			.iov_base = &cmd,
+			.iov_len = sizeof(cmd)
+		};
+
+		memset(&msg, 0, sizeof(msg));
+		msg.msg_iov = &iov;
+		msg.msg_iovlen = 1;
+
+		recvmsg(fd, &msg, 0);
+		int rv = read(fd, &cmd, sizeof(cmd));
+
+		if (rv == sizeof(cmd))
+			handleClientCommand(fd, &cmd);
+	});
+
+	dispatch_resume(socketSource);
+}
+
+void fileHandleToFSRef(const struct file_handle* fh, FSRef* ref)
+{
+	static FSRef rootRef;
+	static dispatch_once_t once;
+
+	dispatch_once(&once, ^{
+		FSPathMakeRef((const UInt8*) "/", &rootRef, NULL);
+	});
+
+	RefData* refData = (RefData*) ref;
+	refData->mount_id = ((RefData*)&rootRef)->mount_id;
+
+	memcpy(&refData->fh, fh, sizeof(FSRef) - sizeof(refData->mount_id));
+}
+
+void setupFANotify(void)
+{
+	// FAN_REPORT_FID = provide file handles
+	// Linux file handle = FSRef in Darling
+	g_fanotify = fanotify_init(FAN_REPORT_FID, 0);
+	if (g_fanotify == -1)
+	{
+		perror("fanotify_init");
+		exit(EXIT_FAILURE);
+	}
+
+	int rv = fanotify_mark(g_fanotify, FAN_MARK_ADD | FAN_MARK_FILESYSTEM,
+		FAN_CREATE | FAN_DELETE | FAN_MOVED_FROM | FAN_MOVED_TO | FAN_MODIFY | FAN_ONDIR, AT_FDCWD, "/");
+	if (rv == -1)
+	{
+		perror("fanotify_mark");
+		exit(EXIT_FAILURE);
+	}
+
+	dispatch_source_t faSource = dispatch_source_create(DISPATCH_SOURCE_TYPE_READ, g_fanotify, 0, dispatch_get_main_queue());
+
+	dispatch_source_set_event_handler(faSource, ^{
+		char events_buf[4096];
+		int len = read(g_fanotify, events_buf, sizeof(events_buf));
+		printf("Read %d bytes of event data\n", len);
+
+		for (struct fanotify_event_metadata* metadata = (struct fanotify_event_metadata *) events_buf;
+            FAN_EVENT_OK(metadata, len);
+            metadata = FAN_EVENT_NEXT(metadata, len))
+		{
+			printf("Event mask: 0x%x\n", metadata->mask);
+			struct fanotify_event_info_fid* fid = (struct fanotify_event_info_fid *) (metadata + 1);
+			if (fid->hdr.info_type == FAN_EVENT_INFO_TYPE_FID)
+			{
+				struct file_handle* fh = (struct file_handle *) fid->handle;
+				FSRef fsref;
+
+				printf("fileHandleToFSRef: bytes: %d, type: %d\n", fh->handle_bytes, fh->handle_type);
+				fileHandleToFSRef(fh, &fsref);
+
+				char pathbuf[1024];
+				printf("FSRefMakePath\n");
+				if (FSRefMakePath(&fsref, (UInt8*)pathbuf, sizeof(pathbuf)) != 0)
+					puts("FSRefMakePath failed");
+				else
+					printf("Event on %s\n", pathbuf);
+			}
+			else
+			{
+				puts("Not a FID");
+			}
+			printf("---\n");
+		}
+	});
+
+	dispatch_resume(faSource);
+}