Mercurial > hg > xemacs-beta
annotate lisp/compat.el @ 617:af57a77cbc92
[xemacs-hg @ 2001-06-18 07:09:50 by ben]
---------------------------------------------------------------
DOCUMENTATION FIXES:
---------------------------------------------------------------
eval.c: Correct documentation.
elhash.c: Doc correction.
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LISP OBJECT CLEANUP:
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bytecode.h, buffer.h, casetab.h, chartab.h, console-msw.h, console.h, database.c, device.h, eldap.h, elhash.h, events.h, extents.h, faces.h, file-coding.h, frame.h, glyphs.h, gui-x.h, gui.h, keymap.h, lisp-disunion.h, lisp-union.h, lisp.h, lrecord.h, lstream.h, mule-charset.h, objects.h, opaque.h, postgresql.h, process.h, rangetab.h, specifier.h, toolbar.h, tooltalk.h, ui-gtk.h: Add wrap_* to all objects (it was already there for a few of them)
-- an expression to encapsulate a pointer into a Lisp object,
rather than the inconvenient XSET*. "wrap" was chosen because
"make" as in make_int(), make_char() is not appropriate. (It
implies allocation. The issue does not exist for ints and chars
because they are not allocated.)
Full error checking has been added to these expressions. When
used without error checking, non-union build, use of these
expressions will incur no loss of efficiency. (In fact, XSET* is
now defined in terms of wrap_* in a non-union build.) In a union
build, you will also get no loss of efficiency provided that you
have a decent optimizing compiler, and a compiler that either
understands inlines or automatically inlines those particular
functions. (And since people don't normally do their production
builds on union, it doesn't matter.)
Update the sample Lisp object definition in lrecord.h accordingly.
dumper.c: Fix places in dumper that referenced wrap_object to reference
its new name, wrap_pointer_1.
buffer.c, bufslots.h, conslots.h, console.c, console.h, devslots.h, device.c, device.h, frame.c, frame.h, frameslots.h, window.c, window.h, winslots.h: -- Extract out the Lisp objects of `struct device' into devslots.h,
just like for the other structures.
-- Extract out the remaining (not copied into the window config)
Lisp objects in `struct window' into winslots.h; use different
macros (WINDOW_SLOT vs. WINDOW_SAVED_SLOT) to differentiate them.
-- Eliminate the `dead' flag of `struct frame', since it
duplicates information already available in `framemeths', and fix
FRAME_LIVE_P accordingly. (Devices and consoles already work this
way.)
-- In *slots.h, switch to system where MARKED_SLOT is automatically
undef'd at the end of the file. (Follows what winslots.h already
does.)
-- Update the comments at the beginning of *slots.h to be accurate.
-- When making any of the above objects dead, zero it out entirely
and reset all Lisp object slots to Qnil. (We were already doing
this somewhat, but not consistently.) This (1) Eliminates the
possibility of extra objects hanging around that ought to be
GC'd, (2) Causes an immediate crash if anyone tries to access a
structure in one of these objects, (3) Ensures consistent behavior
wrt dead objects.
dialog-msw.c: Use internal_object_printer, since this object should not escape.
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FIXING A CRASH THAT I HIT ONCE (AND A RELATED BAD BEHAVIOR):
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eval.c: Fix up some comments about the FSF implementation.
Fix two nasty bugs:
(1) condition_case_unwind frees the conses sitting in the
catch->tag slot too quickly, resulting in a crash that I hit.
(2) catches need to be unwound one at a time when calling
unwind-protect code, rather than all at once at the end; otherwise,
incorrect behavior can result. (A comment shows exactly how.)
backtrace.h: Improve comment about FSF differences in the handler stack.
---------------------------------------------------------------
FIXING A CRASH THAT I REPEATEDLY HIT WHEN USING THE MOUSE WHEEL
UNDER MSWINDOWS:
---------------------------------------------------------------
Basic idea: My crash is due either to a dead, non-marked,
GC-collected frame inside of a window mirror, or a prematurely
freed window mirror. We need to mark the Lisp objects inside of
window mirrors. Tracking the lifespan of window mirrors and
scrollbar instances is extremely hard, and there may well be
lurking bugs where such objects are freed too soon. The only safe
way to fix these problems (and it fixes both problems at once) is
to make both of these structures Lisp objects.
lrecord.h, emacs.c, inline.c, scrollbar-gtk.c, scrollbar-msw.c, scrollbar-x.c, scrollbar.c, scrollbar.h, symsinit.h: Make scrollbar instances actual Lisp objects. Mark the window
mirrors in them. inline.c needs to know about scrollbar.h now.
Record the new type in lrecord.h. Fix up scrollbar-*.c
appropriately. Create a hash table in scrollbar-msw.c so that the
scrollbar instances stored in scrollbar HWND's are properly
GC-protected. Create complex_vars_of_scrollbar_mswindows() to
create the hash table at startup, and call it from emacs.c. Don't
store the scrollbar instance as a property of the GTK scrollbar,
as it's not used and if we did this, we'd have to separately
GC-protect it in a hash table, like in MS Windows.
lrecord.h, frame.h, frame.c, frameslots.h, redisplay.c, window.c, window.h: Move mark_window_mirror from redisplay.c to window.c. Make window
mirrors actual Lisp objects. Tell lrecord.h about them. Change
the window mirror member of struct frame from a pointer to a Lisp
object, and add XWINDOW_MIRROR in appropriate places. Mark the
scrollbar instances in the window mirror.
redisplay.c, redisplay.h, alloc.c: Delete mark_redisplay. Don't call mark_redisplay. We now mark
frame-specific structures in mark_frame.
NOTE: I also deleted an extremely questionable call to
update_frame_window_mirrors(). It was extremely questionable
before, and now totally impossible, since it will create
Lisp objects during redisplay.
frame.c: Mark the scrollbar instances, which are now Lisp objects.
Call mark_gutter() here, not in mark_redisplay().
gutter.c: Update comments about correct marking.
---------------------------------------------------------------
ISSUES BROUGHT UP BY MARTIN:
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buffer.h: Put back these macros the way Steve T and I think they ought to be.
I already explained in a previous changelog entry why I think these
macros should be the way I'd defined them. Once again:
We fix these macros so they don't care about the type of their
lvalues. The non-C-string equivalents of these already function
in the same way, and it's correct because it should be OK to pass
in a CBufbyte *, a BufByte *, a Char_Binary *, an UChar_Binary *,
etc. The whole reason for these different types is to work around
errors caused by signed-vs-unsigned non-matching types. Any
possible error that might be caught in a DFC macro would also be
caught wherever the argument is used elsewhere. So creating
multiple macro versions would add no useful error-checking and
just further complicate an already complicated area.
As for Martin's "ANSI aliasing" bug, XEmacs is not ANSI-aliasing
clean and probably never will be. Unless the board agrees to
change XEmacs in this way (and we really don't want to go down
that road), this is not a bug.
sound.h: Undo Martin's type change.
signal.c: Fix problem identified by Martin with Linux and g++ due to
non-standard declaration of setitimer().
systime.h: Update the docs for "qxe_" to point out why making the
encapsulation explicit is always the right way to go. (setitimer()
itself serves as an example.)
For 21.4:
update-elc-2.el: Correct misplaced parentheses, making lisp/mule not get
recompiled.
| author | ben |
|---|---|
| date | Mon, 18 Jun 2001 07:10:32 +0000 |
| parents | de805c49cfc1 |
| children | 6728e641994e |
| rev | line source |
|---|---|
| 410 | 1 ;;; compat.el --- Mechanism for non-intrusively providing compatibility funs. |
| 2 | |
| 3 ;; Copyright (C) 2000 Ben Wing. | |
| 4 | |
| 5 ;; Author: Ben Wing <ben@xemacs.org> | |
| 6 ;; Maintainer: Ben Wing | |
| 7 ;; Keywords: internal | |
| 8 | |
| 9 ;; This file is part of XEmacs. | |
| 10 | |
| 11 ;; XEmacs is free software; you can redistribute it and/or modify it | |
| 12 ;; under the terms of the GNU General Public License as published by | |
| 13 ;; the Free Software Foundation; either version 2, or (at your option) | |
| 14 ;; any later version. | |
| 15 | |
| 16 ;; XEmacs is distributed in the hope that it will be useful, but | |
| 17 ;; WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 19 ;; General Public License for more details. | |
| 20 | |
| 21 ;; You should have received a copy of the GNU General Public License | |
| 22 ;; along with XEmacs; see the file COPYING. If not, write to the | |
| 23 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
| 24 ;; Boston, MA 02111-1307, USA. | |
| 25 | |
| 26 ;;; Synched up with: Not in FSF. | |
| 27 | |
| 28 ;;; Authorship: | |
| 29 | |
| 30 ; Written May 2000 by Ben Wing. | |
| 31 | |
| 32 ;;; Commentary: | |
| 33 | |
| 34 ;; Typical usage: | |
| 35 | |
| 36 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; | |
| 37 ;; 1. Wrap modules that define compatibility functions like this: ;; | |
| 38 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; | |
| 39 | |
| 40 ;(compat-define-group 'fsf-compat) | |
| 41 | |
| 42 ;(compat-define-functions 'fsf-compat | |
| 43 | |
| 44 ;(defun overlayp (object) | |
| 45 ; "Return t if OBJECT is an overlay." | |
| 46 ; (and (extentp object) | |
| 47 ; (extent-property object 'overlay))) | |
| 48 | |
| 49 ;(defun make-overlay (beg end &optional buffer front-advance rear-advance) | |
| 50 ; ...) | |
| 51 | |
| 52 ;... | |
| 53 | |
| 54 ;) ;; end of (compat-define-group 'fsf-compat) | |
| 55 | |
| 56 ;;;; overlay.el ends here | |
| 57 | |
| 58 | |
| 59 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; | |
| 60 ;; 2. Wrap modules that use the compatibility functions like this: ;; | |
| 61 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; | |
| 62 | |
| 63 ;(compat 'fsf-compat | |
| 64 | |
| 65 ;(defun random-module-my-fun (bar baz) | |
| 66 ; (if (fboundp 'overlays-in) (overlays-in bar baz))) | |
| 67 | |
| 68 ;... | |
| 69 | |
| 70 ;) ;; end of (compat 'fsf-compat) | |
| 71 | |
| 72 ;;;; random-module.el ends here | |
| 73 | |
| 74 | |
| 75 (defun compat-hash-table (group) | |
| 76 (get group 'compat-table)) | |
| 77 | |
| 78 (defun compat-make-hash-table (group) | |
| 79 (put group 'compat-table (make-hash-table))) | |
| 80 | |
| 81 (defmacro compat-define-group (group) | |
| 82 "Define GROUP as a group of compatibility functions. | |
| 83 Individual functions are defined using `compat-define-functions'. | |
| 84 Once defined, the functions can be used by wrapping your code in the | |
| 85 `compat' macro. | |
| 86 | |
| 87 If GROUP is already defined, nothing happens." | |
| 88 (let ((group (eval group))) | |
| 89 (or (hash-table-p (compat-hash-table group)) | |
| 90 (compat-make-hash-table group)))) | |
| 91 | |
| 92 (defmacro compat-clear-functions (group) | |
| 93 "Clear all defined functions and macros out of GROUP." | |
| 94 (let ((group (eval group))) | |
| 95 (clrhash (compat-hash-table group)))) | |
| 96 | |
| 97 (defmacro compat-define-functions (group &rest body) | |
| 98 "Define compatibility functions in GROUP. | |
| 99 You should simply wrap this around the code that defines the functions. | |
| 100 Any functions and macros defined at top level using `defun' or `defmacro' | |
| 101 will be noticed and added to GROUP. Other top-level code will be executed | |
| 102 normally. All code and definitions in this group can safely reference any | |
| 103 other functions in this group -- the code is effectively wrapped in a | |
| 104 `compat' call. You can call `compat-define-functions' more than once, if | |
| 105 necessary, for a single group. | |
| 106 | |
| 107 What actually happens is that the functions and macros defined here are in | |
| 108 fact defined using names prefixed with GROUP. To use these functions, | |
| 109 wrap any calling code with the `compat' macro, which lexically renames | |
| 110 the function and macro calls appropriately." | |
| 111 (let ((group (eval group))) | |
| 112 (let (fundef | |
| 113 (body-tail body)) | |
| 114 (while body-tail | |
| 115 (setq fundef (car body-tail)) | |
| 116 (when (and (consp fundef) (eq (car fundef) 'defun)) | |
| 117 (puthash (second fundef) (third fundef) (compat-hash-table group))) | |
| 118 (when (and (consp fundef) (eq (car fundef) 'defmacro)) | |
| 119 (puthash (second fundef) (third fundef) (compat-hash-table group))) | |
| 120 (setq body-tail (cdr body-tail)))) | |
| 121 (let (fundef | |
| 122 (body-tail body) | |
| 123 result) | |
| 124 (while body-tail | |
| 125 (setq fundef (car body-tail)) | |
| 126 (push | |
| 127 (cond ((and (consp fundef) (eq (car fundef) 'defun)) | |
| 128 (nconc (list 'defun | |
| 129 (intern (concat (symbol-name group) "-" | |
| 130 (symbol-name (second fundef)))) | |
| 131 (third fundef)) | |
| 132 (nthcdr 3 fundef))) | |
| 133 ((and (consp fundef) (eq (car fundef) 'defmacro)) | |
| 134 (nconc (list 'defmacro | |
| 135 (intern (concat (symbol-name group) "-" | |
| 136 (symbol-name (second fundef)))) | |
| 137 (third fundef)) | |
| 138 (nthcdr 3 fundef))) | |
| 139 (t fundef)) | |
| 140 result) | |
| 141 (setq body-tail (cdr body-tail))) | |
| 142 (nconc (list 'compat (list 'quote group)) (nreverse result))))) | |
| 143 | |
| 144 (defvar compat-active-groups nil) | |
| 145 | |
| 146 (defun compat-fboundp (groups fun) | |
| 147 "T if FUN is either `fboundp' or one of the compatibility funs in GROUPS. | |
| 148 GROUPS is a list of compatibility groups as defined using | |
| 149 `compat-define-group'." | |
| 150 (or (fboundp fun) | |
| 151 (block nil | |
| 152 (mapcar #'(lambda (group) | |
| 153 (if (gethash fun (compat-hash-table group)) | |
| 154 (return t))) | |
| 155 groups)))) | |
| 156 | |
| 157 (defmacro compat (group &rest body) | |
| 158 "Make use of compatibility functions and macros in GROUP. | |
| 159 You should simply wrap this around the code that uses the functions | |
| 160 and macros in GROUP. Typically, a call to `compat' should be placed | |
| 161 at the top of an ELisp module, with the closing parenthesis at the | |
| 162 bottom; use this in place of a `require' statement. Wrapped code can | |
| 163 be either function or macro definitions or other ELisp code, and | |
| 164 wrapped function or macro definitions need not be at top level. All | |
| 165 calls to the compatibility functions or macros will be noticed anywhere | |
| 166 within the wrapped code. Calls to `fboundp' within the wrapped code | |
| 167 will also behave correctly when called on compatibility functions and | |
| 168 macros, even though they would return nil elsewhere (including in code | |
| 169 in other modules called dynamically from the wrapped code). | |
| 170 | |
| 171 The functions and macros define in GROUP are actually defined under | |
| 172 prefixed names, to avoid namespace clashes and bad interactions with | |
| 173 other code that calls `fboundp'. All calls inside of the wrapped code | |
| 174 to the compatibility functions and macros in GROUP are lexically | |
| 175 mapped to the prefixed names. Since this is a lexical mapping, code | |
| 176 in other modules that is called by functions in this module will not | |
| 177 be affected." | |
| 178 (let ((group (eval group)) | |
| 179 defs) | |
| 180 (maphash | |
| 181 #'(lambda (fun args) | |
| 182 (push | |
| 183 (list fun args | |
| 184 (nconc | |
| 185 (list 'list | |
| 186 (list 'quote | |
| 187 (intern (concat (symbol-name group) "-" | |
| 188 (symbol-name fun))))) | |
| 189 args)) | |
| 190 defs)) | |
| 191 (compat-hash-table group)) | |
| 192 ;; it would be cleaner to use `lexical-let' instead of `let', but that | |
| 193 ;; causes function definitions to have obnoxious, unreadable junk in | |
| 194 ;; them. #### Move `lexical-let' into C!!! | |
| 195 `(let ((compat-active-groups (cons ',group compat-active-groups))) | |
| 196 (macrolet ((fboundp (fun) `(compat-fboundp ',compat-active-groups ,fun)) | |
| 197 ,@defs) | |
| 198 ,@body)))) |
