File synchronization fixes.

* admin/CPP-DEFINES (BSD_SYSTEM, HAVE_FSYNC): Remove.
* admin/merge-gnulib (GNULIB_MODULES): Add fsync, fdatasync.
* configure.ac (BSD_SYSTEM, BSD_SYSTEM_AHB): Remove; no longer needed.
(fsync): Remove check; now done by gnulib.
* lib/fdatasync.c, lib/fsync.c, m4/fdatasync.m4, m4/fsync.m4:
New files, from gnulib.
* lib/gnulib.mk, m4/gnulib-comp.m4: Regenerate.
* lib-src/Makefile.in (LIB_FDATASYNC): New macro.
(emacsclient${EXEEXT}): Use it.
* lib-src/emacsclient.c (main): Use fdatasync, not fsync, since we don't
care about metadata.  Keep trying if interrupted.
* lib-src/movemail.c (main, popmail): Don't worry about BSD_SYSTEM, since
fsync is available everywhere (or there is a substitute).  Don't
report an error if fsync returns EINVAL.
* nt/inc/ms-w32.h (fdatasync): New macro, suggested by Eli Zaretskii.
* src/Makefile.in (LIB_FDATASYNC): New macro.
(LIBES): Use it.
* src/conf_post.h (BSD_SYSTEM, BSD_SYSTEM_AHB): Remove; no longer needed.
* src/fileio.c (Fwrite_region, write_region_inhibit_fsync):
Don't worry about HAVE_FSYNC, since a substitute fsync is
available if the system lacks one.
(Fwrite_regin): Retry fsync if interrupted.

Fixes: debbugs:13944

1 files changed, 3 insertions, 1 deletions

diff --git a/lib-src/Makefile.in b/lib-src/Makefile.in
index 8a6960ee2fe..7069af9767a 100644
--- a/lib-src/Makefile.in
+++ b/lib-src/Makefile.in
@@ -161,6 +161,8 @@ LIBRESOLV=@LIBRESOLV@
 LIBS_MAIL=@LIBS_MAIL@
 ## empty or -lrt or -lposix4 if HAVE_CLOCK_GETTIME
 LIB_CLOCK_GETTIME = @LIB_CLOCK_GETTIME@
+## empty or -lrt or -lposix4 if HAVE_FDATASYNC
+LIB_FDATASYNC = @LIB_FDATASYNC@
 
 ## Extra libraries to use when linking movemail.
 LIBS_MOVE = $(LIBS_MAIL) $(KRB4LIB) $(DESLIB) $(KRB5LIB) $(CRYPTOLIB) \
@@ -334,7 +336,7 @@ pop.o: ${srcdir}/pop.c ${srcdir}/../lib/min-max.h $(config_h)
 emacsclient${EXEEXT}: ${srcdir}/emacsclient.c $(config_h)
         $(CC) ${ALL_CFLAGS} ${srcdir}/emacsclient.c \
            -DVERSION="\"${version}\"" \
-           $(LOADLIBES) -o emacsclient
+           $(LOADLIBES) $(LIB_FDATASYNC) -o emacsclient
 
 hexl${EXEEXT}: ${srcdir}/hexl.c $(config_h)
         $(CC) ${ALL_CFLAGS} ${srcdir}/hexl.c $(LOADLIBES) -o hexl