Mercurial > hg > xemacs-beta
view src/filelock.c @ 4952:19a72041c5ed
Mule-izing, various fixes related to char * arguments
-------------------- ChangeLog entries follow: --------------------
modules/ChangeLog addition:
2010-01-26 Ben Wing <ben@xemacs.org>
* postgresql/postgresql.c:
* postgresql/postgresql.c (CHECK_LIVE_CONNECTION):
* postgresql/postgresql.c (print_pgresult):
* postgresql/postgresql.c (Fpq_conn_defaults):
* postgresql/postgresql.c (Fpq_connectdb):
* postgresql/postgresql.c (Fpq_connect_start):
* postgresql/postgresql.c (Fpq_result_status):
* postgresql/postgresql.c (Fpq_res_status):
Mule-ize large parts of it.
2010-01-26 Ben Wing <ben@xemacs.org>
* ldap/eldap.c (print_ldap):
* ldap/eldap.c (allocate_ldap):
Use write_ascstring().
src/ChangeLog addition:
2010-01-26 Ben Wing <ben@xemacs.org>
* alloc.c:
* alloc.c (build_ascstring):
* alloc.c (build_msg_cistring):
* alloc.c (staticpro_1):
* alloc.c (staticpro_name):
* alloc.c (staticpro_nodump_1):
* alloc.c (staticpro_nodump_name):
* alloc.c (unstaticpro_nodump_1):
* alloc.c (mcpro_1):
* alloc.c (mcpro_name):
* alloc.c (object_memory_usage_stats):
* alloc.c (common_init_alloc_early):
* alloc.c (init_alloc_once_early):
* buffer.c (print_buffer):
* buffer.c (vars_of_buffer):
* buffer.c (common_init_complex_vars_of_buffer):
* buffer.c (init_initial_directory):
* bytecode.c (invalid_byte_code):
* bytecode.c (print_compiled_function):
* bytecode.c (mark_compiled_function):
* chartab.c (print_table_entry):
* chartab.c (print_char_table):
* config.h.in:
* console-gtk.c:
* console-gtk.c (gtk_device_to_console_connection):
* console-gtk.c (gtk_semi_canonicalize_console_connection):
* console-gtk.c (gtk_canonicalize_console_connection):
* console-gtk.c (gtk_semi_canonicalize_device_connection):
* console-gtk.c (gtk_canonicalize_device_connection):
* console-stream.c (stream_init_frame_1):
* console-stream.c (vars_of_console_stream):
* console-stream.c (init_console_stream):
* console-x.c (x_semi_canonicalize_console_connection):
* console-x.c (x_semi_canonicalize_device_connection):
* console-x.c (x_canonicalize_device_connection):
* console-x.h:
* data.c (eq_with_ebola_notice):
* data.c (Fsubr_interactive):
* data.c (Fnumber_to_string):
* data.c (digit_to_number):
* device-gtk.c (gtk_init_device):
* device-msw.c (print_devmode):
* device-x.c (x_event_name):
* dialog-msw.c (handle_directory_dialog_box):
* dialog-msw.c (handle_file_dialog_box):
* dialog-msw.c (vars_of_dialog_mswindows):
* doc.c (weird_doc):
* doc.c (Fsnarf_documentation):
* doc.c (vars_of_doc):
* dumper.c (pdump):
* dynarr.c:
* dynarr.c (Dynarr_realloc):
* editfns.c (Fuser_real_login_name):
* editfns.c (get_home_directory):
* elhash.c (print_hash_table_data):
* elhash.c (print_hash_table):
* emacs.c (main_1):
* emacs.c (vars_of_emacs):
* emodules.c:
* emodules.c (_emodules_list):
* emodules.c (Fload_module):
* emodules.c (Funload_module):
* emodules.c (Flist_modules):
* emodules.c (find_make_module):
* emodules.c (attempt_module_delete):
* emodules.c (emodules_load):
* emodules.c (emodules_doc_subr):
* emodules.c (emodules_doc_sym):
* emodules.c (syms_of_module):
* emodules.c (vars_of_module):
* emodules.h:
* eval.c (print_subr):
* eval.c (signal_call_debugger):
* eval.c (build_error_data):
* eval.c (signal_error):
* eval.c (maybe_signal_error):
* eval.c (signal_continuable_error):
* eval.c (maybe_signal_continuable_error):
* eval.c (signal_error_2):
* eval.c (maybe_signal_error_2):
* eval.c (signal_continuable_error_2):
* eval.c (maybe_signal_continuable_error_2):
* eval.c (signal_ferror):
* eval.c (maybe_signal_ferror):
* eval.c (signal_continuable_ferror):
* eval.c (maybe_signal_continuable_ferror):
* eval.c (signal_ferror_with_frob):
* eval.c (maybe_signal_ferror_with_frob):
* eval.c (signal_continuable_ferror_with_frob):
* eval.c (maybe_signal_continuable_ferror_with_frob):
* eval.c (syntax_error):
* eval.c (syntax_error_2):
* eval.c (maybe_syntax_error):
* eval.c (sferror):
* eval.c (sferror_2):
* eval.c (maybe_sferror):
* eval.c (invalid_argument):
* eval.c (invalid_argument_2):
* eval.c (maybe_invalid_argument):
* eval.c (invalid_constant):
* eval.c (invalid_constant_2):
* eval.c (maybe_invalid_constant):
* eval.c (invalid_operation):
* eval.c (invalid_operation_2):
* eval.c (maybe_invalid_operation):
* eval.c (invalid_change):
* eval.c (invalid_change_2):
* eval.c (maybe_invalid_change):
* eval.c (invalid_state):
* eval.c (invalid_state_2):
* eval.c (maybe_invalid_state):
* eval.c (wtaerror):
* eval.c (stack_overflow):
* eval.c (out_of_memory):
* eval.c (print_multiple_value):
* eval.c (issue_call_trapping_problems_warning):
* eval.c (backtrace_specials):
* eval.c (backtrace_unevalled_args):
* eval.c (Fbacktrace):
* eval.c (warn_when_safe):
* event-Xt.c (modwarn):
* event-Xt.c (modbarf):
* event-Xt.c (check_modifier):
* event-Xt.c (store_modifier):
* event-Xt.c (emacs_Xt_format_magic_event):
* event-Xt.c (describe_event):
* event-gtk.c (dragndrop_data_received):
* event-gtk.c (store_modifier):
* event-gtk.c (gtk_reset_modifier_mapping):
* event-msw.c (dde_eval_string):
* event-msw.c (Fdde_alloc_advise_item):
* event-msw.c (mswindows_dde_callback):
* event-msw.c (FROB):
* event-msw.c (emacs_mswindows_format_magic_event):
* event-stream.c (external_debugging_print_event):
* event-stream.c (execute_help_form):
* event-stream.c (vars_of_event_stream):
* events.c (print_event_1):
* events.c (print_event):
* events.c (event_equal):
* extents.c (print_extent_1):
* extents.c (print_extent):
* extents.c (vars_of_extents):
* faces.c (print_face):
* faces.c (complex_vars_of_faces):
* file-coding.c:
* file-coding.c (print_coding_system):
* file-coding.c (print_coding_system_in_print_method):
* file-coding.c (default_query_method):
* file-coding.c (find_coding_system):
* file-coding.c (make_coding_system_1):
* file-coding.c (chain_print):
* file-coding.c (undecided_print):
* file-coding.c (gzip_print):
* file-coding.c (vars_of_file_coding):
* file-coding.c (complex_vars_of_file_coding):
* fileio.c:
* fileio.c (report_file_type_error):
* fileio.c (report_error_with_errno):
* fileio.c (report_file_error):
* fileio.c (barf_or_query_if_file_exists):
* fileio.c (vars_of_fileio):
* floatfns.c (matherr):
* fns.c (print_bit_vector):
* fns.c (Fmapconcat):
* fns.c (add_suffix_to_symbol):
* fns.c (add_prefix_to_symbol):
* frame-gtk.c:
* frame-gtk.c (Fgtk_window_id):
* frame-x.c (def):
* frame-x.c (x_cde_transfer_callback):
* frame.c:
* frame.c (Fmake_frame):
* gc.c (show_gc_cursor_and_message):
* gc.c (vars_of_gc):
* glyphs-eimage.c (png_instantiate):
* glyphs-eimage.c (tiff_instantiate):
* glyphs-gtk.c (gtk_print_image_instance):
* glyphs-msw.c (mswindows_print_image_instance):
* glyphs-x.c (x_print_image_instance):
* glyphs-x.c (update_widget_face):
* glyphs.c (make_string_from_file):
* glyphs.c (print_image_instance):
* glyphs.c (signal_image_error):
* glyphs.c (signal_image_error_2):
* glyphs.c (signal_double_image_error):
* glyphs.c (signal_double_image_error_2):
* glyphs.c (xbm_mask_file_munging):
* glyphs.c (pixmap_to_lisp_data):
* glyphs.h:
* gui.c (gui_item_display_flush_left):
* hpplay.c (player_error_internal):
* hpplay.c (myHandler):
* intl-win32.c:
* intl-win32.c (langcode_to_lang):
* intl-win32.c (sublangcode_to_lang):
* intl-win32.c (Fmswindows_get_locale_info):
* intl-win32.c (lcid_to_locale_mule_or_no):
* intl-win32.c (mswindows_multibyte_to_unicode_print):
* intl-win32.c (complex_vars_of_intl_win32):
* keymap.c:
* keymap.c (print_keymap):
* keymap.c (ensure_meta_prefix_char_keymapp):
* keymap.c (Fkey_description):
* keymap.c (Ftext_char_description):
* lisp.h:
* lisp.h (struct):
* lisp.h (DECLARE_INLINE_HEADER):
* lread.c (Fload_internal):
* lread.c (locate_file):
* lread.c (read_escape):
* lread.c (read_raw_string):
* lread.c (read1):
* lread.c (read_list):
* lread.c (read_compiled_function):
* lread.c (init_lread):
* lrecord.h:
* marker.c (print_marker):
* marker.c (marker_equal):
* menubar-msw.c (displayable_menu_item):
* menubar-x.c (command_builder_operate_menu_accelerator):
* menubar.c (vars_of_menubar):
* minibuf.c (reinit_complex_vars_of_minibuf):
* minibuf.c (complex_vars_of_minibuf):
* mule-charset.c (Fmake_charset):
* mule-charset.c (complex_vars_of_mule_charset):
* mule-coding.c (iso2022_print):
* mule-coding.c (fixed_width_query):
* number.c (bignum_print):
* number.c (ratio_print):
* number.c (bigfloat_print):
* number.c (bigfloat_finalize):
* objects-msw.c:
* objects-msw.c (mswindows_color_to_string):
* objects-msw.c (mswindows_color_list):
* objects-tty.c:
* objects-tty.c (tty_font_list):
* objects-tty.c (tty_find_charset_font):
* objects-xlike-inc.c (xft_find_charset_font):
* objects-xlike-inc.c (endif):
* print.c:
* print.c (write_istring):
* print.c (write_ascstring):
* print.c (Fterpri):
* print.c (Fprint):
* print.c (print_error_message):
* print.c (print_vector_internal):
* print.c (print_cons):
* print.c (print_string):
* print.c (printing_unreadable_object):
* print.c (print_internal):
* print.c (print_float):
* print.c (print_symbol):
* process-nt.c (mswindows_report_winsock_error):
* process-nt.c (nt_canonicalize_host_name):
* process-unix.c (unix_canonicalize_host_name):
* process.c (print_process):
* process.c (report_process_error):
* process.c (report_network_error):
* process.c (make_process_internal):
* process.c (Fstart_process_internal):
* process.c (status_message):
* process.c (putenv_internal):
* process.c (vars_of_process):
* process.h:
* profile.c (vars_of_profile):
* rangetab.c (print_range_table):
* realpath.c (vars_of_realpath):
* redisplay.c (vars_of_redisplay):
* search.c (wordify):
* search.c (Freplace_match):
* sheap.c (sheap_adjust_h):
* sound.c (report_sound_error):
* sound.c (Fplay_sound_file):
* specifier.c (print_specifier):
* symbols.c (Fsubr_name):
* symbols.c (do_symval_forwarding):
* symbols.c (set_default_buffer_slot_variable):
* symbols.c (set_default_console_slot_variable):
* symbols.c (store_symval_forwarding):
* symbols.c (default_value):
* symbols.c (defsymbol_massage_name_1):
* symbols.c (defsymbol_massage_name_nodump):
* symbols.c (defsymbol_massage_name):
* symbols.c (defsymbol_massage_multiword_predicate_nodump):
* symbols.c (defsymbol_massage_multiword_predicate):
* symbols.c (defsymbol_nodump):
* symbols.c (defsymbol):
* symbols.c (defkeyword):
* symbols.c (defkeyword_massage_name):
* symbols.c (check_module_subr):
* symbols.c (deferror_1):
* symbols.c (deferror):
* symbols.c (deferror_massage_name):
* symbols.c (deferror_massage_name_and_message):
* symbols.c (defvar_magic):
* symeval.h:
* symeval.h (DEFVAR_SYMVAL_FWD):
* sysdep.c:
* sysdep.c (init_system_name):
* sysdll.c:
* sysdll.c (MAYBE_PREPEND_UNDERSCORE):
* sysdll.c (dll_function):
* sysdll.c (dll_variable):
* sysdll.c (dll_error):
* sysdll.c (dll_open):
* sysdll.c (dll_close):
* sysdll.c (image_for_address):
* sysdll.c (my_find_image):
* sysdll.c (search_linked_libs):
* sysdll.h:
* sysfile.h:
* sysfile.h (DEFAULT_DIRECTORY_FALLBACK):
* syswindows.h:
* tests.c (DFC_CHECK_LENGTH):
* tests.c (DFC_CHECK_CONTENT):
* tests.c (Ftest_hash_tables):
* text.c (vars_of_text):
* text.h:
* tooltalk.c (tt_opnum_string):
* tooltalk.c (tt_message_arg_ival_string):
* tooltalk.c (Ftooltalk_default_procid):
* tooltalk.c (Ftooltalk_default_session):
* tooltalk.c (init_tooltalk):
* tooltalk.c (vars_of_tooltalk):
* ui-gtk.c (Fdll_load):
* ui-gtk.c (type_to_marshaller_type):
* ui-gtk.c (Fgtk_import_function_internal):
* ui-gtk.c (emacs_gtk_object_printer):
* ui-gtk.c (emacs_gtk_boxed_printer):
* unicode.c (unicode_to_ichar):
* unicode.c (unicode_print):
* unicode.c (unicode_query):
* unicode.c (vars_of_unicode):
* unicode.c (complex_vars_of_unicode):
* win32.c:
* win32.c (mswindows_report_process_error):
* window.c (print_window):
* xemacs.def.in.in:
BASIC IDEA: Further fixing up uses of char * and CIbyte *
to reflect their actual semantics; Mule-izing some code;
redoing of the not-yet-working code to handle message translation.
Clean up code to handle message-translation (not yet working).
Create separate versions of build_msg_string() for working with
Ibyte *, CIbyte *, and Ascbyte * arguments. Assert that Ascbyte *
arguments are pure-ASCII. Make build_msg_string() be the same
as build_msg_ascstring(). Create same three versions of GETTEXT()
and DEFER_GETTEXT(). Also create build_defer_string() and
variants for the equivalent of DEFER_GETTEXT() when building a
string. Remove old CGETTEXT(). Clean up code where GETTEXT(),
DEFER_GETTEXT(), build_msg_string(), etc. was being called and
introduce some new calls to build_msg_string(), etc. Remove
GETTEXT() from calls to weird_doc() -- we assume that the
message snarfer knows about weird_doc(). Remove uses of
DEFER_GETTEXT() from error messages in sysdep.c and instead use
special comments /* @@@begin-snarf@@@ */ and /* @@@end-snarf@@@ */
that the message snarfer presumably knows about.
Create build_ascstring() and use it in many instances in place
of build_string(). The purpose of having Ascbyte * variants is
to make the code more self-documenting in terms of what sort of
semantics is expected for char * strings. In fact in the process
of looking for uses of build_string(), much improperly Mule-ized
was discovered.
Mule-ize a lot of code as described in previous paragraph,
e.g. in sysdep.c.
Make the error functions take Ascbyte * strings and fix up a
couple of places where non-pure-ASCII strings were being passed in
(file-coding.c, mule-coding.c, unicode.c). (It's debatable whether
we really need to make the error functions work this way. It
helps catch places where code is written in a way that message
translation won't work, but we may well never implement message
translation.)
Make staticpro() and friends take Ascbyte * strings instead of
raw char * strings. Create a const_Ascbyte_ptr dynarr type
to describe what's held by staticpro_names[] and friends,
create pdump descriptions for const_Ascbyte_ptr dynarrs, and
use them in place of specially-crafted staticpro descriptions.
Mule-ize certain other functions (e.g. x_event_name) by correcting
raw use of char * to Ascbyte *, Rawbyte * or another such type,
and raw use of char[] buffers to another type (usually Ascbyte[]).
Change many uses of write_c_string() to write_msg_string(),
write_ascstring(), etc.
Mule-ize emodules.c, emodules.h, sysdll.h.
Fix some un-Mule-ized code in intl-win32.c.
A comment in event-Xt.c and the limitations of the message
snarfer (make-msgfile or whatever) is presumably incorrect --
it should be smart enough to handle function calls spread over
more than one line. Clean up code in event-Xt.c that was
written awkwardly for this reason.
In config.h.in, instead of NEED_ERROR_CHECK_TYPES_INLINES,
create a more general XEMACS_DEFS_NEEDS_INLINE_DECLS to
indicate when inlined functions need to be declared in
xemacs.defs.in.in, and make use of it in xemacs.defs.in.in.
We need to do this because postgresql.c now calls qxestrdup(),
which is an inline function.
Make nconc2() and other such functions MODULE_API and put
them in xemacs.defs.in.in since postgresql.c now uses them.
Clean up indentation in lread.c and a few other places.
In text.h, document ASSERT_ASCTEXT_ASCII() and
ASSERT_ASCTEXT_ASCII_LEN(), group together the stand-in
encodings and add some more for DLL symbols, function and
variable names, etc.
| author | Ben Wing <ben@xemacs.org> |
|---|---|
| date | Tue, 26 Jan 2010 23:22:30 -0600 |
| parents | ecf1ebac70d8 |
| children | 304aebb79cd3 |
line wrap: on
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/* Copyright (C) 1985, 86, 87, 93, 94, 96 Free Software Foundation, Inc. Copyright (C) 2001 Ben Wing. This file is part of XEmacs. XEmacs 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 2, or (at your option) any later version. XEmacs 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 XEmacs; see the file COPYING. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* Synced with FSF 20.2 */ #include <config.h> #include "lisp.h" #include "buffer.h" #include <paths.h> #include "sysdir.h" #include "sysfile.h" #include "sysproc.h" /* for qxe_getpid() */ #include "syspwd.h" #include "syssignal.h" /* for kill. */ Lisp_Object Qask_user_about_supersession_threat; Lisp_Object Qask_user_about_lock; int inhibit_clash_detection; #ifdef CLASH_DETECTION /* The strategy: to lock a file FN, create a symlink .#FN in FN's directory, with link data `user@host.pid'. This avoids a single mount (== failure) point for lock files. When the host in the lock data is the current host, we can check if the pid is valid with kill. Otherwise, we could look at a separate file that maps hostnames to reboot times to see if the remote pid can possibly be valid, since we don't want Emacs to have to communicate via pipes or sockets or whatever to other processes, either locally or remotely; rms says that's too unreliable. Hence the separate file, which could theoretically be updated by daemons running separately -- but this whole idea is unimplemented; in practice, at least in our environment, it seems such stale locks arise fairly infrequently, and Emacs' standard methods of dealing with clashes suffice. We use symlinks instead of normal files because (1) they can be stored more efficiently on the filesystem, since the kernel knows they will be small, and (2) all the info about the lock can be read in a single system call (readlink). Although we could use regular files to be useful on old systems lacking symlinks, nowadays virtually all such systems are probably single-user anyway, so it didn't seem worth the complication. Similarly, we don't worry about a possible 14-character limit on file names, because those are all the same systems that don't have symlinks. This is compatible with the locking scheme used by Interleaf (which has contributed this implementation for Emacs), and was designed by Ethan Jacobson, Kimbo Mundy, and others. --karl@cs.umb.edu/karl@hq.ileaf.com. */ /* Here is the structure that stores information about a lock. */ typedef struct { Ibyte *user; Ibyte *host; pid_t pid; } lock_info_type; /* When we read the info back, we might need this much more, enough for decimal representation plus null. */ #define LOCK_PID_MAX (4 * sizeof (pid_t)) /* Free the two dynamically-allocated pieces in PTR. */ #define FREE_LOCK_INFO(i) do { \ xfree ((i).user, Ibyte *); \ xfree ((i).host, Ibyte *); \ } while (0) /* Write the name of the lock file for FN into LFNAME. Length will be that of FN plus two more for the leading `.#' plus one for the null. */ #define MAKE_LOCK_NAME(lock, file) \ (lock = alloca_ibytes (XSTRING_LENGTH (file) + 2 + 1), \ fill_in_lock_file_name (lock, file)) static void fill_in_lock_file_name (Ibyte *lockfile, Lisp_Object fn) { Ibyte *file_name = XSTRING_DATA (fn); Ibyte *p; Bytecount dirlen; for (p = file_name + XSTRING_LENGTH (fn) - 1; p > file_name && !IS_ANY_SEP (p[-1]); p--) ; dirlen = p - file_name; memcpy (lockfile, file_name, dirlen); p = lockfile + dirlen; *(p++) = '.'; *(p++) = '#'; memcpy (p, file_name + dirlen, XSTRING_LENGTH (fn) - dirlen + 1); } /* Lock the lock file named LFNAME. If FORCE is nonzero, we do so even if it is already locked. Return 1 if successful, 0 if not. */ static int lock_file_1 (Ibyte *lfname, int force) { /* Does not GC. */ int err; Ibyte *lock_info_str; Ibyte *host_name; Ibyte *user_name = user_login_name (NULL); if (user_name == NULL) user_name = (Ibyte *) ""; if (STRINGP (Vsystem_name)) host_name = XSTRING_DATA (Vsystem_name); else host_name = (Ibyte *) ""; lock_info_str = alloca_ibytes (qxestrlen (user_name) + qxestrlen (host_name) + LOCK_PID_MAX + 5); qxesprintf (lock_info_str, "%s@%s.%d", user_name, host_name, qxe_getpid ()); err = qxe_symlink (lock_info_str, lfname); if (err != 0 && errno == EEXIST && force) { qxe_unlink (lfname); err = qxe_symlink (lock_info_str, lfname); } return err == 0; } /* Return 0 if nobody owns the lock file LFNAME or the lock is obsolete, 1 if another process owns it (and set OWNER (if non-null) to info), 2 if the current process owns it, or -1 if something is wrong with the locking mechanism. */ static int current_lock_owner (lock_info_type *owner, Ibyte *lfname) { /* Does not GC. */ int len, ret; int local_owner = 0; Ibyte *at, *dot; Ibyte *lfinfo = 0; int bufsize = 50; /* Read arbitrarily-long contents of symlink. Similar code in file-symlink-p in fileio.c. */ do { bufsize *= 2; lfinfo = (Ibyte *) xrealloc (lfinfo, bufsize); len = qxe_readlink (lfname, lfinfo, bufsize); } while (len >= bufsize); /* If nonexistent lock file, all is well; otherwise, got strange error. */ if (len == -1) { xfree (lfinfo, Ibyte *); return errno == ENOENT ? 0 : -1; } /* Link info exists, so `len' is its length. Null terminate. */ lfinfo[len] = 0; /* Even if the caller doesn't want the owner info, we still have to read it to determine return value, so allocate it. */ if (!owner) { owner = alloca_new (lock_info_type); local_owner = 1; } /* Parse USER@HOST.PID. If can't parse, return -1. */ /* The USER is everything before the first @. */ at = qxestrchr (lfinfo, '@'); dot = qxestrrchr (lfinfo, '.'); if (!at || !dot) { xfree (lfinfo, Ibyte *); return -1; } len = at - lfinfo; owner->user = xnew_ibytes (len + 1); qxestrncpy (owner->user, lfinfo, len); owner->user[len] = 0; /* The PID is everything after the last `.'. */ owner->pid = atoi ((CIbyte *) dot + 1); /* The host is everything in between. */ len = dot - at - 1; owner->host = xnew_ibytes (len + 1); qxestrncpy (owner->host, at + 1, len); owner->host[len] = 0; /* We're done looking at the link info. */ xfree (lfinfo, Ibyte *); /* On current host? */ if (STRINGP (Fsystem_name ()) && qxestrcmp (owner->host, XSTRING_DATA (Fsystem_name ())) == 0) { if (owner->pid == qxe_getpid ()) ret = 2; /* We own it. */ else if (owner->pid > 0 && (kill (owner->pid, 0) >= 0 || errno == EPERM)) ret = 1; /* An existing process on this machine owns it. */ /* The owner process is dead or has a strange pid (<=0), so try to zap the lockfile. */ else if (qxe_unlink (lfname) < 0) ret = -1; else ret = 0; } else { /* If we wanted to support the check for stale locks on remote machines, here's where we'd do it. */ ret = 1; } /* Avoid garbage. */ if (local_owner || ret <= 0) { FREE_LOCK_INFO (*owner); } return ret; } /* Lock the lock named LFNAME if possible. Return 0 in that case. Return positive if some other process owns the lock, and info about that process in CLASHER. Return -1 if cannot lock for any other reason. */ static int lock_if_free (lock_info_type *clasher, Ibyte *lfname) { /* Does not GC. */ if (lock_file_1 ((Ibyte *) lfname, 0) == 0) { int locker; if (errno != EEXIST) return -1; locker = current_lock_owner (clasher, lfname); if (locker == 2) { FREE_LOCK_INFO (*clasher); return 0; /* We ourselves locked it. */ } else if (locker == 1) return 1; /* Someone else has it. */ return -1; /* Something's wrong. */ } return 0; } /* lock_file locks file FN, meaning it serves notice on the world that you intend to edit that file. This should be done only when about to modify a file-visiting buffer previously unmodified. Do not (normally) call this for a buffer already modified, as either the file is already locked, or the user has already decided to go ahead without locking. When this returns, either the lock is locked for us, or the user has said to go ahead without locking. If the file is locked by someone else, this calls ask-user-about-lock (a Lisp function) with two arguments, the file name and info about the user who did the locking. This function can signal an error, or return t meaning take away the lock, or return nil meaning ignore the lock. */ void lock_file (Lisp_Object fn) { /* This function can GC. GC checked 7-11-00 ben */ /* dmoore - and can destroy current_buffer and all sorts of other mean nasty things with pointy teeth. If you call this make sure you protect things right. */ /* Somebody updated the code in this function and removed the previous comment. -slb */ register Lisp_Object attack, orig_fn; register Ibyte *lfname, *locker; lock_info_type lock_info; struct gcpro gcpro1, gcpro2, gcpro3; Lisp_Object old_current_buffer; Lisp_Object subject_buf; if (inhibit_clash_detection) return; old_current_buffer = wrap_buffer (current_buffer); subject_buf = Qnil; GCPRO3 (fn, subject_buf, old_current_buffer); orig_fn = fn; fn = Fexpand_file_name (fn, Qnil); /* Create the name of the lock-file for file fn */ MAKE_LOCK_NAME (lfname, fn); /* See if this file is visited and has changed on disk since it was visited. */ { subject_buf = get_truename_buffer (orig_fn); if (!NILP (subject_buf) && NILP (Fverify_visited_file_modtime (subject_buf)) && !NILP (Ffile_exists_p (fn))) call1_in_buffer (XBUFFER (subject_buf), Qask_user_about_supersession_threat, fn); } /* Try to lock the lock. */ if (current_buffer != XBUFFER (old_current_buffer) || lock_if_free (&lock_info, lfname) <= 0) /* Return now if we have locked it, or if lock creation failed or current buffer is killed. */ goto done; /* Else consider breaking the lock */ locker = alloca_ibytes (qxestrlen (lock_info.user) + qxestrlen (lock_info.host) + LOCK_PID_MAX + 9); qxesprintf (locker, "%s@%s (pid %d)", lock_info.user, lock_info.host, lock_info.pid); FREE_LOCK_INFO (lock_info); attack = call2_in_buffer (BUFFERP (subject_buf) ? XBUFFER (subject_buf) : current_buffer, Qask_user_about_lock , fn, build_intstring (locker)); if (!NILP (attack) && current_buffer == XBUFFER (old_current_buffer)) /* User says take the lock */ { lock_file_1 (lfname, 1); goto done; } /* User says ignore the lock */ done: UNGCPRO; } void unlock_file (Lisp_Object fn) { /* This can GC */ register Ibyte *lfname; struct gcpro gcpro1; GCPRO1 (fn); fn = Fexpand_file_name (fn, Qnil); MAKE_LOCK_NAME (lfname, fn); if (current_lock_owner (0, lfname) == 2) qxe_unlink (lfname); UNGCPRO; } void unlock_all_files (void) { register Lisp_Object tail; for (tail = Vbuffer_alist; CONSP (tail); tail = XCDR (tail)) { struct buffer *b = XBUFFER (XCDR (XCAR (tail))); if (STRINGP (b->file_truename) && BUF_SAVE_MODIFF (b) < BUF_MODIFF (b)) unlock_file (b->file_truename); } } DEFUN ("lock-buffer", Flock_buffer, 0, 1, 0, /* Lock FILE, if current buffer is modified. FILE defaults to current buffer's visited file, or else nothing is done if current buffer isn't visiting a file. */ (file)) { if (NILP (file)) file = current_buffer->file_truename; CHECK_STRING (file); if (BUF_SAVE_MODIFF (current_buffer) < BUF_MODIFF (current_buffer) && !NILP (file)) lock_file (file); return Qnil; } DEFUN ("unlock-buffer", Funlock_buffer, 0, 0, 0, /* Unlock the file visited in the current buffer, if it should normally be locked. */ ()) { /* This function can GC */ /* dmoore - and can destroy current_buffer and all sorts of other mean nasty things with pointy teeth. If you call this make sure you protect things right. */ if (BUF_SAVE_MODIFF (current_buffer) < BUF_MODIFF (current_buffer) && STRINGP (current_buffer->file_truename)) unlock_file (current_buffer->file_truename); return Qnil; } /* Unlock the file visited in buffer BUFFER. */ void unlock_buffer (struct buffer *buffer) { /* This function can GC */ /* dmoore - and can destroy current_buffer and all sorts of other mean nasty things with pointy teeth. If you call this make sure you protect things right. */ if (BUF_SAVE_MODIFF (buffer) < BUF_MODIFF (buffer) && STRINGP (buffer->file_truename)) unlock_file (buffer->file_truename); } DEFUN ("file-locked-p", Ffile_locked_p, 0, 1, 0, /* Return nil if the FILENAME is not locked, t if it is locked by you, else a string of the name of the locker. */ (filename)) { Lisp_Object ret; register Ibyte *lfname; int owner; lock_info_type locker; struct gcpro gcpro1; GCPRO1 (filename); filename = Fexpand_file_name (filename, Qnil); MAKE_LOCK_NAME (lfname, filename); owner = current_lock_owner (&locker, lfname); if (owner <= 0) ret = Qnil; else if (owner == 2) ret = Qt; else ret = build_intstring (locker.user); if (owner > 0) FREE_LOCK_INFO (locker); UNGCPRO; return ret; } /* Initialization functions. */ void syms_of_filelock (void) { /* This function can GC */ DEFSUBR (Funlock_buffer); DEFSUBR (Flock_buffer); DEFSUBR (Ffile_locked_p); DEFSYMBOL (Qask_user_about_supersession_threat); DEFSYMBOL (Qask_user_about_lock); } void vars_of_filelock (void) { DEFVAR_BOOL ("inhibit-clash-detection", &inhibit_clash_detection /* Non-nil inhibits creation of lock file to detect clash. */); inhibit_clash_detection = 0; } #endif /* CLASH_DETECTION */