This simplifies Emacs a bit, since it no longer needs to worry
about closing file descriptors by hand in some cases.
It also fixes some unlikely races. Not all such races, as
libraries often open files internally without setting
close-on-exec, but it's an improvement.
* admin/merge-gnulib (GNULIB_MODULES): Add fcntl, pipe2.
(GNULIB_TOOL_FLAGS): Avoid binary-io, close. Do not avoid fcntl.
* configure.ac (mkostemp): New function to check for.
(PTY_OPEN): Pass O_CLOEXEC to posix_openpt.
* lib/fcntl.c, lib/getdtablesize.c, lib/pipe2.c, m4/fcntl.m4:
* m4/getdtablesize.m4, m4/pipe2.m4: New files, taken from gnulib.
* lib/gnulib.mk, m4/gnulib-comp.m4: Regenerate.
* nt/gnulib.mk: Remove empty gl_GNULIB_ENABLED_verify section;
otherwise, gnulib-tool complains given close-on-exec changes.
* nt/inc/ms-w32.h (pipe): Remove.
* nt/mingw-cfg.site (ac_cv_func_fcntl, gl_cv_func_fcntl_f_dupfd_cloexec)
(gl_cv_func_fcntl_f_dupfd_works, ac_cv_func_pipe2): New vars.
* src/alloc.c (valid_pointer_p) [!WINDOWSNT]:
* src/callproc.c (Fcall_process) [!MSDOS]:
* src/emacs.c (main) [!DOS_NT]:
* src/nsterm.m (ns_term_init):
* src/process.c (create_process):
Use 'pipe2' with O_CLOEXEC instead of 'pipe'.
* src/emacs.c (Fcall_process_region) [HAVE_MKOSTEMP]:
* src/filelock.c (create_lock_file) [HAVE_MKOSTEMP]:
Prefer mkostemp with O_CLOEXEC to mkstemp.
* src/callproc.c (relocate_fd) [!WINDOWSNT]:
* src/emacs.c (main): Use F_DUPFD_CLOEXEC, not plain F_DUPFD.
No need to use fcntl (..., F_SETFD, FD_CLOEXEC), since we're
now using pipe2.
* src/filelock.c (create_lock_file) [! HAVE_MKOSTEMP]:
Make the resulting file descriptor close-on-exec.
* src/lisp.h, src/lread.c, src/process.c (close_load_descs, close_process_descs):
* src/lread.c (load_descriptor_list, load_descriptor_unwind):
Remove; no longer needed. All uses removed.
* src/process.c (SOCK_CLOEXEC): Define to 0 if not supplied by system.
(close_on_exec, accept4, process_socket) [!SOCK_CLOEXEC]:
New functions.
(socket) [!SOCK_CLOEXEC]: Supply a substitute.
(Fmake_network_process, Fnetwork_interface_list):
(Fnetwork_interface_info, server_accept_connection):
Make newly-created socket close-on-exec.
* src/sysdep.c (emacs_open, emacs_fopen):
Make new-created descriptor close-on-exec.
* src/w32.c (fcntl): Support F_DUPFD_CLOEXEC well enough for Emacs.
* src/w32.c, src/w32.h (pipe2): Rename from 'pipe', with new flags arg.
Fixes: debbugs:14803
* configure.ac: Remove -with-acl option, since Gnulib does that for
us now.
(LIBACL_LIBS): Remove; no longer needed.
* lib/Makefile.am (CLEANFILES, SUFFIXES): New (empty) macros,
for the benefit of the new ACL implementation.
* lib/makefile.w32-in (GNULIBOBJS): Add $(BLD)/acl-errno-valid.$(O).
($(BLD)/acl-errno-valid.$(O)): New rule.
* lib/acl-errno-valid.c, lib/acl-internal.h, lib/acl.h:
* lib/acl_entries.c, lib/errno.in.h, lib/file-has-acl.c:
* lib/qcopy-acl.c, lib/qset-acl.c, m4/acl.m4, m4/errno_h.m4:
New files, taken from gnulib.
* lib/gnulib.mk, m4/gnulib-comp.m4: Regenerate.
* admin/merge-gnulib (GNULIB_MODULES): Add qacl.
(GNULIB_TOOL_FLAGS): Do not avoid errno.
* etc/NEWS: Emacs is no longer limited to POSIX ACLs. --disable-acl,
not --without-acl, since we're now using Gnulib's implementation.
* nt/config.nt (HAVE_ACL_SET_FILE): Rename from HAVE_POSIX_ACL.
* nt/inc/ms-w32.h (EOPNOTSUPP): New macro.
* src/Makefile.in (LIB_ACL): New macro.
(LIBACL_LIBS): Remove.
(LIBES): Use LIB_ACL, not LIBACL_LIBS.
* src/fileio.c: Include <acl.h>.
Use HAVE_ACL_SET_FILE rather than HAVE_POSIX_ACL.
(ACL_NOT_WELL_SUPPORTED): Remove. All uses replaced by
!acl_errno_valid.
(Fcopy_file) [!WINDOWSNT]: Use qcopy_acl instead of rolling
it ourselves.
Fixes: debbugs:14295
Reported by ׃scar Fuentes in
http://lists.gnu.org/archive/html/emacs-devel/2013-03/msg00733.html
nt/inc/ms-w32.h (_WIN32_WINNT) [!_W64]: Don't define for MinGW64.
nt/inc/sys/stat.h (chmod): Remove _CRTIMP from prototype.
src/w32.c (_PROCESS_MEMORY_COUNTERS_EX) [_WIN32_WINNT < 0x0500]:
Define only for _WIN32_WINNT less than 0x0500.
Reported by ׃scar Fuentes in
http://lists.gnu.org/archive/html/emacs-devel/2013-03/msg00699.html
and in
http://lists.gnu.org/archive/html/emacs-devel/2013-03/msg00707.html.
nt/inc/ms-w32.h (USE_NO_MINGW_SETJMP_TWO_ARGS) [_W64]: Define to 1.
For MinGW64, include sys/types.h and time.h.
nt/inc/sys/time.h (struct timeval) [!_W64]: Guard definition with _W64.
(struct timezone) [!_TIMEZONE_DEFINED]: Guard definition with
_TIMEZONE_DEFINED.
nt/addpm.c (_WIN32_IE) [_W64]: For MinGW64, don't define to 0x400.
nt/inc/sys/stat.h: Remove _CRTIMP from prototypes of fstat, stat,
lstat, and fstatat.
lib-src/ntlib.c (struct timespec) [!_TIMEZONE_DEFINED]: Define the
struct only if _TIMEZONE_DEFINED is not defined.
src/w32term.c (WCRANGE, GLYPHSET): Don't define if _W64 is defined.
src/w32.c (REPARSE_DATA_BUFFER): Guard with
MAXIMUM_REPARSE_DATA_BUFFER_SIZE being defined.
Problems were reported by ׃scar Fuentes in
http://lists.gnu.org/archive/html/emacs-devel/2013-03/msg00611.html.
nt/inc/ms-w32.h (struct timespec): Don't define if
_TIMESPEC_DEFINED is already defined.
(sigset_t) [!_POSIX]: Typedef for MinGW64.
(_WIN32_WINNT, WIN32_LEAN_AND_MEAN): Move definitions before
including the first system header, to avoid redefinition if some
system header defines a default value.
nt/inc/sys/time.h (struct itimerval): Don't define if
_TIMESPEC_DEFINED is already defined.
* 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
* etc/NEWS: Document this.
* nt/inc/unistd.h (O_NOFOLLOW): New macro.
* src/filelock.c: Include <c-ctype.h>.
(MAX_LFINFO): New top-level constant.
(lock_info_type): Remove members pid, boot_time. Add members at,
dot, colon. Change user member to be the entire buffer, not a
pointer. This allows us to handle the case where a foreign
pid or boot time exceeds the local range. All uses changed.
(LINKS_MIGHT_NOT_WORK): New constant.
(FREE_LOCK_INFO): Remove, as the pieces no longer need freeing.
(defined_WINDOWSNT): Remove.
(MAKE_LOCK_NAME, file_in_lock_file_name):
Always use .#FILE (not .#-FILE) for the file lock,
even if it is a regular file.
(rename_lock_file): New function.
(create_lock_file): Use it.
(create_lock_file, read_lock_data):
Prefer a symbolic link for the lock file, falling back on a
regular file if symlinks don't work. Do not try to create
symlinks on MS-Windows, due to security hassles. Stick with
POSIXish functions (open, read, write, close, fchmod, readlink, symlink,
link, rename, unlink, mkstemp) when creating locks, as a GNUish
host may be using a Windowsish file system, and cannot use
MS-Windows-only system calls. Fall back on mktemp if mkstemp
doesn't work. Don't fail merely because of a symlink-contents
length limit in the current file system; fall back on regular
files. Increase the symlink contents length limit to 8 KiB, this
should be big enough for any real use and doesn't crunch the
stack.
(create_lock_file, lock_file_1, read_lock_data):
Simplify allocation of lock file buffers now that they fit in 8 KiB.
(lock_file_1): Return error number, not bool. All callers changed.
(ELOOP): New macro, if not already defined.
(read_lock_data): Return size of lock file contents, not Lisp object.
All callers changed. Handle a race condition if some other process
replaces a regular-file lock with a symlink lock or vice versa,
while we're trying to read the lock.
(current_lock_owner): Parse contents more carefully, to help avoid
confusing a regular-file lock with some other application's use
of the file. Check for lock file contents being too long, or
not parsing correctly.
(current_lock_owner, lock_file):
Allow foreign pid and boot times that exceed the local range.
(current_lock_owner, lock_if_free, lock_file):
Simplify allocation of lock file contents.
* src/w32.c (sys_rename_replace): New function, containing most of
the contents of the old sys_rename.
(sys_rename): Use it.
(fchmod): New dummy function.
* src/w32.h (sys_rename_replace, fchmod): New decls.
Fixes: debbugs:13807
src/filelock.c [WINDOWSNT]: Include w32.h.
(MAKE_LOCK_NAME): Don't use 'lock', it clashes with MS runtime
function of that name. Up-case the macro arguments.
(IS_LOCK_FILE): New macro.
(fill_in_lock_file_name): Use IS_LOCK_FILE instead of S_ISLNK.
(create_lock_file): New function, with body extracted from
lock_file_1.
[WINDOWSNT]: Implement lock files by writing a regular file with
the lock information as its contents.
(read_lock_data): New function, on Posix platforms just calls
emacs_readlinkat.
[WINDOWSNT]: Read the lock info from the file.
(current_lock_owner): Call read_lock_data instead of calling
emacs_readlinkat directly.
(lock_file) [WINDOWSNT]: Run the file name through
dostounix_filename.
src/w32proc.c (sys_kill): Support the case of SIG = 0, in which case
just check if the process by that PID exists.
src/w32.c (sys_open): Don't reset the _O_CREAT flag if _O_EXCL is
also present, as doing so will fail to error out if the file
already exists.
src/makefile.w32-in ($(BLD)/filelock.$(O)): Depend on src/w32.h.
nt/inc/ms-w32.h (BOOT_TIME_FILE): Define.
nt/config.nt (CLASH_DETECTION): Define to 1.
lisp/emacs-lisp/bytecomp.el (byte-recompile-directory): Reject files
that match "\`\.#", to avoid compiling lock files, even if they
are readable (as they are on MS-Windows).
doc/emacs/files.texi (Interlocking): Don't refer to symlinks as the
exclusive means of locking files.
etc/NEWS: Mention support for lock files on MS-Windows.
On my host, this speeds up directory-files-and-attributes by a
factor of 3, when applied to Emacs's src directory.
These functions are standardized by POSIX and are common these
days; fall back on a (slower) gnulib implementation if the host
is too old to supply them.
* .bzrignore: Add lib/dirent.h.
* lib/Makefile.am (libgnu_a_SOURCES): Add openat-die.c, save-cwd.c.
* lib/careadlinkat.c, lib/careadlinkat.h: Merge from gnulib,
incorporating: 2013-01-29 careadlinkat: do not provide careadlinkatcwd.
* lib/gnulib.mk, m4/gnulib-comp.m4: Regenerate.
* lib/dirent.in.h, lib/fdopendir.c, lib/fstatat.c, lib/openat-priv.h:
* lib/openat-proc.c, lib/openat.h, m4/dirent_h.m4, m4/fdopendir.m4:
* m4/fstatat.m4: New files, from gnulib.
* lib/openat-die.c, lib/save-cwd.c, lib/save-cwd.h: New files.
These last three are specific to Emacs and are not copied from gnulib.
They are simpler than the gnulib versions and are tuned for Emacs.
* admin/merge-gnulib (GNULIB_MODULES): Add fdopendir, fstatat, readlinkat.
(GNULIB_TOOL_FLAGS): Do not avoid at-internal, openat-h.
Avoid dup, open, opendir.
* nt/inc/sys/stat.h (fstatat):
* nt/inc/unistd.h (readlinkat): New decls.
* src/conf_post.h (GNULIB_SUPPORT_ONLY_AT_FDCWD): Remove.
* src/dired.c: Include <fcntl.h>.
(open_directory): New function, which uses open and fdopendir
rather than opendir. DOS_NT platforms still use opendir, though.
(directory_files_internal, file_name_completion): Use it.
(file_attributes): New function, with most of the old Ffile_attributes.
(directory_files_internal, Ffile_attributes): Use it.
(file_attributes, file_name_completion_stat): First arg is now fd,
not dir name. All uses changed. Use fstatat rather than lstat +
stat.
(file_attributes): Use emacs_readlinkat rather than Ffile_symlink_p.
* src/fileio.c: Include <allocator.h>, <careadlinkat.h>.
(emacs_readlinkat): New function, with much of the old
Ffile_symlink_p, but with an fd argument for speed.
It uses readlinkat rather than careadlinkatcwd, so that it
need not assume the working directory.
(Ffile_symlink_p): Use it.
* src/filelock.c (current_lock_owner): Use emacs_readlinkat
rather than emacs_readlink.
* src/lisp.h (emacs_readlinkat): New decl.
(READLINK_BUFSIZE, emacs_readlink): Remove.
* src/sysdep.c: Do not include <allocator.h>, <careadlinkat.h>.
(emacs_norealloc_allocator, emacs_readlink): Remove.
This stuff is moved to fileio.c.
* src/w32.c (fstatat, readlinkat): New functions.
(careadlinkat): Don't check that fd == AT_FDCWD.
(careadlinkatcwd): Remove; no longer needed.
Fixes: debbugs:13539
nt/inc/sys/stat.h (S_ISMPX): Define to zero, to accommodate changes
in lib/filemode.c that broke the MS-Windows build.
Suggested by Andy Moreton <andrewjmoreton@gmail.com>.
src/w32.c: Include sddl.h and sys/acl.h.
(SDDL_REVISION_1): Define if not already defined.
(g_b_init_get_security_descriptor_dacl)
(g_b_init_convert_sd_to_sddl, g_b_init_convert_sddl_to_sd)
(g_b_init_is_valid_security_descriptor)
(g_b_init_set_file_security): New static flags.
(globals_of_w32): Initialize them to zero.
(SetFileSecurity_Name): New string constant.
(SetFileSecurity_Proc, GetSecurityDescriptorDacl_Proc)
(ConvertStringSecurityDescriptorToSecurityDescriptor_Proc)
(ConvertSecurityDescriptorToStringSecurityDescriptor_Proc)
(IsValidSecurityDescriptor_Proc): New typedefs.
(get_file_security, get_security_descriptor_owner)
(get_security_descriptor_group): Set errno to ENOTSUP.
(set_file_security, get_security_descriptor_dacl)
(is_valid_security_descriptor, convert_sd_to_sddl)
(convert_sddl_to_sd, acl_valid, acl_to_text, acl_from_text)
(acl_free, acl_get_file, acl_set_file): New functions.
src/fileio.c (Fcopy_file) [WINDOWSNT]: Support copying ACLs.
nt/inc/sys/acl.h: New file.
nt/inc/ms-w32.h (ENOTSUP): Define if undefined.
nt/config.nt (HAVE_POSIX_ACL): Define.
doc/lispref/files.texi (File Attributes, Changing Files): Update to include
MS-Windows support for ACLs.
src/w32.h (_child_process): New members input_file and
pending_deletion.
(register_child): First argument is now pid_t.
(record_infile, record_pending_deletion): New prototypes.
src/w32proc.c (new_child): Initialize input_file and
pending_deletion members of the child.
(delete_child): Delete the child's temporary input file, if any,
that is pending deletion.
(register_child): First argument is now pid_t.
(record_infile, record_pending_deletion): New functions.
(reap_subprocess): Fix a typo in DebPrint string.
(sys_spawnve, sys_kill): Use pid_t for PID arguments.
src/fileio.c (internal_delete_file): Return an int again: non-zero
if delete-file succeeds, zero otherwise.
src/lisp.h (internal_delete_file): Adjust prototype.
src/callproc.c (Fcall_process): Don't overwrite infile with result
of DECODE_FILE.
[WINDOWSNT] If BUFFER is an integer, i.e. we are launching an
asynchronous subprocess, record the name of the input file name,
if any.
(delete_temp_file) [WINDOWSNT]: If internal_delete_file fails to
delete the file, record it as pending deletion when the subprocess
exits.
nt/inc/ms-w32.h (sys_unlink): Provide prototype.
src/w32.c (stat_worker): If w32_stat_get_owner_group is zero, do not
try to get accurate owner and group information from NT file
security APIs. This is to make most callers of 'stat' and
'lstat', which don't need that information, much faster.
src/dired.c (Ffile_attributes) [WINDOWSNT]: Set
w32_stat_get_owner_group to a non-zero value, to request accurate
owner and group information from 'lstat'.
nt/inc/sys/stat.h: Declare w32_stat_get_owner_group.
