fsmonitor: deduplicate settings logic for Unix platforms

The macOS fsm-settings-darwin.c is applicable to other Unix variants
as well.  Rename it to fsm-settings-unix.c, using the safer
xstrdup()+dirname() approach and including the "vfat" filesystem check.

Now that both fsm-ipc and fsm-settings use the "unix" variant name,
set FSMONITOR_OS_SETTINGS to "unix" for macOS in config.mak.uname and
remove the if/else conditionals from the build files.

Signed-off-by: Paul Tarjan <github@paulisageek.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: ptarjan

Makefile

@@ -2323,15 +2323,11 @@ ifdef FSMONITOR_DAEMON_BACKEND
 	COMPAT_CFLAGS += -DHAVE_FSMONITOR_DAEMON_BACKEND
 	COMPAT_OBJS += compat/fsmonitor/fsm-listen-$(FSMONITOR_DAEMON_BACKEND).o
 	COMPAT_OBJS += compat/fsmonitor/fsm-health-$(FSMONITOR_DAEMON_BACKEND).o
-ifeq ($(FSMONITOR_DAEMON_BACKEND),win32)
-	COMPAT_OBJS += compat/fsmonitor/fsm-ipc-win32.o
-else
-	COMPAT_OBJS += compat/fsmonitor/fsm-ipc-unix.o
-endif
 endif
 
 ifdef FSMONITOR_OS_SETTINGS
 	COMPAT_CFLAGS += -DHAVE_FSMONITOR_OS_SETTINGS
+	COMPAT_OBJS += compat/fsmonitor/fsm-ipc-$(FSMONITOR_OS_SETTINGS).o
 	COMPAT_OBJS += compat/fsmonitor/fsm-settings-$(FSMONITOR_OS_SETTINGS).o
 	COMPAT_OBJS += compat/fsmonitor/fsm-path-utils-$(FSMONITOR_DAEMON_BACKEND).o
 endif

compat/fsmonitor/fsm-settings-darwin.c compat/fsmonitor/fsm-settings-unix.ccompat/fsmonitor/fsm-settings-darwin.c renamed to compat/fsmonitor/fsm-settings-unix.c

@@ -5,7 +5,7 @@
 #include "fsmonitor-settings.h"
 #include "fsmonitor-path-utils.h"
 
- /*
+/*
  * For the builtin FSMonitor, we create the Unix domain socket for the
  * IPC in the .git directory.  If the working directory is remote,
  * then the socket will be created on the remote file system.  This
@@ -22,25 +22,31 @@
  * The builtin FSMonitor uses a Unix domain socket in the .git
  * directory for IPC.  These Windows drive formats do not support
  * Unix domain sockets, so mark them as incompatible for the daemon.
- *
  */
 static enum fsmonitor_reason check_uds_volume(struct repository *r)
 {
 	struct fs_info fs;
 	const char *ipc_path = fsmonitor_ipc__get_path(r);
-	struct strbuf path = STRBUF_INIT;
-	strbuf_add(&path, ipc_path, strlen(ipc_path));
+	char *path;
+	char *dir;
+
+	/*
+	 * Create a copy for dirname() since it may modify its argument.
+	 */
+	path = xstrdup(ipc_path);
+	dir = dirname(path);
 
-	if (fsmonitor__get_fs_info(dirname(path.buf), &fs) == -1) {
-		strbuf_release(&path);
+	if (fsmonitor__get_fs_info(dir, &fs) == -1) {
+		free(path);
 		return FSMONITOR_REASON_ERROR;
 	}
 
-	strbuf_release(&path);
+	free(path);
 
 	if (fs.is_remote ||
-		!strcmp(fs.typename, "msdos") ||
-		!strcmp(fs.typename, "ntfs")) {
+	    !strcmp(fs.typename, "msdos") ||
+	    !strcmp(fs.typename, "ntfs") ||
+	    !strcmp(fs.typename, "vfat")) {
 		free(fs.typename);
 		return FSMONITOR_REASON_NOSOCKETS;
 	}

config.mak.uname

@@ -178,7 +178,7 @@ ifeq ($(uname_S),Darwin)
         ifndef NO_PTHREADS
         ifndef NO_UNIX_SOCKETS
 	FSMONITOR_DAEMON_BACKEND = darwin
-	FSMONITOR_OS_SETTINGS = darwin
+	FSMONITOR_OS_SETTINGS = unix
         endif
         endif
 

contrib/buildsystems/CMakeLists.txt

@@ -291,23 +291,22 @@ endif()
 
 if(SUPPORTS_SIMPLE_IPC)
 	if(CMAKE_SYSTEM_NAME STREQUAL "Windows")
-		add_compile_definitions(HAVE_FSMONITOR_DAEMON_BACKEND)
-		list(APPEND compat_SOURCES compat/fsmonitor/fsm-listen-win32.c)
-		list(APPEND compat_SOURCES compat/fsmonitor/fsm-health-win32.c)
-		list(APPEND compat_SOURCES compat/fsmonitor/fsm-ipc-win32.c)
-		list(APPEND compat_SOURCES compat/fsmonitor/fsm-path-utils-win32.c)
-
-		add_compile_definitions(HAVE_FSMONITOR_OS_SETTINGS)
-		list(APPEND compat_SOURCES compat/fsmonitor/fsm-settings-win32.c)
+		set(FSMONITOR_DAEMON_BACKEND "win32")
+		set(FSMONITOR_OS_SETTINGS "win32")
 	elseif(CMAKE_SYSTEM_NAME STREQUAL "Darwin")
+		set(FSMONITOR_DAEMON_BACKEND "darwin")
+		set(FSMONITOR_OS_SETTINGS "unix")
+	endif()
+
+	if(FSMONITOR_DAEMON_BACKEND)
 		add_compile_definitions(HAVE_FSMONITOR_DAEMON_BACKEND)
-		list(APPEND compat_SOURCES compat/fsmonitor/fsm-listen-darwin.c)
-		list(APPEND compat_SOURCES compat/fsmonitor/fsm-health-darwin.c)
-		list(APPEND compat_SOURCES compat/fsmonitor/fsm-ipc-unix.c)
-		list(APPEND compat_SOURCES compat/fsmonitor/fsm-path-utils-darwin.c)
+		list(APPEND compat_SOURCES compat/fsmonitor/fsm-listen-${FSMONITOR_DAEMON_BACKEND}.c)
+		list(APPEND compat_SOURCES compat/fsmonitor/fsm-health-${FSMONITOR_DAEMON_BACKEND}.c)
+		list(APPEND compat_SOURCES compat/fsmonitor/fsm-path-utils-${FSMONITOR_DAEMON_BACKEND}.c)
+		list(APPEND compat_SOURCES compat/fsmonitor/fsm-ipc-${FSMONITOR_OS_SETTINGS}.c)
 
 		add_compile_definitions(HAVE_FSMONITOR_OS_SETTINGS)
-		list(APPEND compat_SOURCES compat/fsmonitor/fsm-settings-darwin.c)
+		list(APPEND compat_SOURCES compat/fsmonitor/fsm-settings-${FSMONITOR_OS_SETTINGS}.c)
 	endif()
 endif()
 

meson.build

@@ -1320,10 +1320,13 @@ else
 endif
 
 fsmonitor_backend = ''
+fsmonitor_os = ''
 if host_machine.system() == 'windows'
   fsmonitor_backend = 'win32'
+  fsmonitor_os = 'win32'
 elif host_machine.system() == 'darwin'
   fsmonitor_backend = 'darwin'
+  fsmonitor_os = 'unix'
   libgit_dependencies += dependency('CoreServices')
 endif
 if fsmonitor_backend != ''
@@ -1334,17 +1337,12 @@ if fsmonitor_backend != ''
     'compat/fsmonitor/fsm-health-' + fsmonitor_backend + '.c',
     'compat/fsmonitor/fsm-listen-' + fsmonitor_backend + '.c',
     'compat/fsmonitor/fsm-path-utils-' + fsmonitor_backend + '.c',
-    'compat/fsmonitor/fsm-settings-' + fsmonitor_backend + '.c',
+    'compat/fsmonitor/fsm-ipc-' + fsmonitor_os + '.c',
+    'compat/fsmonitor/fsm-settings-' + fsmonitor_os + '.c',
   ]
-
-  if fsmonitor_backend == 'win32'
-    libgit_sources += 'compat/fsmonitor/fsm-ipc-win32.c'
-  else
-    libgit_sources += 'compat/fsmonitor/fsm-ipc-unix.c'
-  endif
 endif
 build_options_config.set_quoted('FSMONITOR_DAEMON_BACKEND', fsmonitor_backend)
-build_options_config.set_quoted('FSMONITOR_OS_SETTINGS', fsmonitor_backend)
+build_options_config.set_quoted('FSMONITOR_OS_SETTINGS', fsmonitor_os)
 
 if not get_option('b_sanitize').contains('address') and get_option('regex').allowed() and compiler.has_header('regex.h') and compiler.get_define('REG_STARTEND', prefix: '#include <regex.h>') != ''
   build_options_config.set('NO_REGEX', '')