Mercurial > hg > xemacs-beta
diff src/redisplay.h @ 665:fdefd0186b75
[xemacs-hg @ 2001-09-20 06:28:42 by ben]
The great integral types renaming.
The purpose of this is to rationalize the names used for various
integral types, so that they match their intended uses and follow
consist conventions, and eliminate types that were not semantically
different from each other.
The conventions are:
-- All integral types that measure quantities of anything are
signed. Some people disagree vociferously with this, but their
arguments are mostly theoretical, and are vastly outweighed by
the practical headaches of mixing signed and unsigned values,
and more importantly by the far increased likelihood of
inadvertent bugs: Because of the broken "viral" nature of
unsigned quantities in C (operations involving mixed
signed/unsigned are done unsigned, when exactly the opposite is
nearly always wanted), even a single error in declaring a
quantity unsigned that should be signed, or even the even more
subtle error of comparing signed and unsigned values and
forgetting the necessary cast, can be catastrophic, as
comparisons will yield wrong results. -Wsign-compare is turned
on specifically to catch this, but this tends to result in a
great number of warnings when mixing signed and unsigned, and
the casts are annoying. More has been written on this
elsewhere.
-- All such quantity types just mentioned boil down to EMACS_INT,
which is 32 bits on 32-bit machines and 64 bits on 64-bit
machines. This is guaranteed to be the same size as Lisp
objects of type `int', and (as far as I can tell) of size_t
(unsigned!) and ssize_t. The only type below that is not an
EMACS_INT is Hashcode, which is an unsigned value of the same
size as EMACS_INT.
-- Type names should be relatively short (no more than 10
characters or so), with the first letter capitalized and no
underscores if they can at all be avoided.
-- "count" == a zero-based measurement of some quantity. Includes
sizes, offsets, and indexes.
-- "bpos" == a one-based measurement of a position in a buffer.
"Charbpos" and "Bytebpos" count text in the buffer, rather than
bytes in memory; thus Bytebpos does not directly correspond to
the memory representation. Use "Membpos" for this.
-- "Char" refers to internal-format characters, not to the C type
"char", which is really a byte.
-- For the actual name changes, see the script below.
I ran the following script to do the conversion. (NOTE: This script
is idempotent. You can safely run it multiple times and it will
not screw up previous results -- in fact, it will do nothing if
nothing has changed. Thus, it can be run repeatedly as necessary
to handle patches coming in from old workspaces, or old branches.)
There are two tags, just before and just after the change:
`pre-integral-type-rename' and `post-integral-type-rename'. When
merging code from the main trunk into a branch, the best thing to
do is first merge up to `pre-integral-type-rename', then apply the
script and associated changes, then merge from
`post-integral-type-change' to the present. (Alternatively, just do
the merging in one operation; but you may then have a lot of
conflicts needing to be resolved by hand.)
Script `fixtypes.sh' follows:
----------------------------------- cut ------------------------------------
files="*.[ch] s/*.h m/*.h config.h.in ../configure.in Makefile.in.in ../lib-src/*.[ch] ../lwlib/*.[ch]"
gr Memory_Count Bytecount $files
gr Lstream_Data_Count Bytecount $files
gr Element_Count Elemcount $files
gr Hash_Code Hashcode $files
gr extcount bytecount $files
gr bufpos charbpos $files
gr bytind bytebpos $files
gr memind membpos $files
gr bufbyte intbyte $files
gr Extcount Bytecount $files
gr Bufpos Charbpos $files
gr Bytind Bytebpos $files
gr Memind Membpos $files
gr Bufbyte Intbyte $files
gr EXTCOUNT BYTECOUNT $files
gr BUFPOS CHARBPOS $files
gr BYTIND BYTEBPOS $files
gr MEMIND MEMBPOS $files
gr BUFBYTE INTBYTE $files
gr MEMORY_COUNT BYTECOUNT $files
gr LSTREAM_DATA_COUNT BYTECOUNT $files
gr ELEMENT_COUNT ELEMCOUNT $files
gr HASH_CODE HASHCODE $files
----------------------------------- cut ------------------------------------
`fixtypes.sh' is a Bourne-shell script; it uses 'gr':
----------------------------------- cut ------------------------------------
#!/bin/sh
# Usage is like this:
# gr FROM TO FILES ...
# globally replace FROM with TO in FILES. FROM and TO are regular expressions.
# backup files are stored in the `backup' directory.
from="$1"
to="$2"
shift 2
echo ${1+"$@"} | xargs global-replace "s/$from/$to/g"
----------------------------------- cut ------------------------------------
`gr' in turn uses a Perl script to do its real work,
`global-replace', which follows:
----------------------------------- cut ------------------------------------
: #-*- Perl -*-
### global-modify --- modify the contents of a file by a Perl expression
## Copyright (C) 1999 Martin Buchholz.
## Copyright (C) 2001 Ben Wing.
## Authors: Martin Buchholz <martin@xemacs.org>, Ben Wing <ben@xemacs.org>
## Maintainer: Ben Wing <ben@xemacs.org>
## Current Version: 1.0, May 5, 2001
# This program 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.
#
# This program 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.
eval 'exec perl -w -S $0 ${1+"$@"}'
if 0;
use strict;
use FileHandle;
use Carp;
use Getopt::Long;
use File::Basename;
(my $myName = $0) =~ s@.*/@@; my $usage="
Usage: $myName [--help] [--backup-dir=DIR] [--line-mode] [--hunk-mode]
PERLEXPR FILE ...
Globally modify a file, either line by line or in one big hunk.
Typical usage is like this:
[with GNU print, GNU xargs: guaranteed to handle spaces, quotes, etc.
in file names]
find . -name '*.[ch]' -print0 | xargs -0 $0 's/\bCONST\b/const/g'\n
[with non-GNU print, xargs]
find . -name '*.[ch]' -print | xargs $0 's/\bCONST\b/const/g'\n
The file is read in, either line by line (with --line-mode specified)
or in one big hunk (with --hunk-mode specified; it's the default), and
the Perl expression is then evalled with \$_ set to the line or hunk of
text, including the terminating newline if there is one. It should
destructively modify the value there, storing the changed result in \$_.
Files in which any modifications are made are backed up to the directory
specified using --backup-dir, or to `backup' by default. To disable this,
use --backup-dir= with no argument.
Hunk mode is the default because it is MUCH MUCH faster than line-by-line.
Use line-by-line only when it matters, e.g. you want to do a replacement
only once per line (the default without the `g' argument). Conversely,
when using hunk mode, *ALWAYS* use `g'; otherwise, you will only make one
replacement in the entire file!
";
my %options = ();
$Getopt::Long::ignorecase = 0;
&GetOptions (
\%options,
'help', 'backup-dir=s', 'line-mode', 'hunk-mode',
);
die $usage if $options{"help"} or @ARGV <= 1;
my $code = shift;
die $usage if grep (-d || ! -w, @ARGV);
sub SafeOpen {
open ((my $fh = new FileHandle), $_[0]);
confess "Can't open $_[0]: $!" if ! defined $fh;
return $fh;
}
sub SafeClose {
close $_[0] or confess "Can't close $_[0]: $!";
}
sub FileContents {
my $fh = SafeOpen ("< $_[0]");
my $olddollarslash = $/;
local $/ = undef;
my $contents = <$fh>;
$/ = $olddollarslash;
return $contents;
}
sub WriteStringToFile {
my $fh = SafeOpen ("> $_[0]");
binmode $fh;
print $fh $_[1] or confess "$_[0]: $!\n";
SafeClose $fh;
}
foreach my $file (@ARGV) {
my $changed_p = 0;
my $new_contents = "";
if ($options{"line-mode"}) {
my $fh = SafeOpen $file;
while (<$fh>) {
my $save_line = $_;
eval $code;
$changed_p = 1 if $save_line ne $_;
$new_contents .= $_;
}
} else {
my $orig_contents = $_ = FileContents $file;
eval $code;
if ($_ ne $orig_contents) {
$changed_p = 1;
$new_contents = $_;
}
}
if ($changed_p) {
my $backdir = $options{"backup-dir"};
$backdir = "backup" if !defined ($backdir);
if ($backdir) {
my ($name, $path, $suffix) = fileparse ($file, "");
my $backfulldir = $path . $backdir;
my $backfile = "$backfulldir/$name";
mkdir $backfulldir, 0755 unless -d $backfulldir;
print "modifying $file (original saved in $backfile)\n";
rename $file, $backfile;
}
WriteStringToFile ($file, $new_contents);
}
}
----------------------------------- cut ------------------------------------
In addition to those programs, I needed to fix up a few other
things, particularly relating to the duplicate definitions of
types, now that some types merged with others. Specifically:
1. in lisp.h, removed duplicate declarations of Bytecount. The
changed code should now look like this: (In each code snippet
below, the first and last lines are the same as the original, as
are all lines outside of those lines. That allows you to locate
the section to be replaced, and replace the stuff in that
section, verifying that there isn't anything new added that
would need to be kept.)
--------------------------------- snip -------------------------------------
/* Counts of bytes or chars */
typedef EMACS_INT Bytecount;
typedef EMACS_INT Charcount;
/* Counts of elements */
typedef EMACS_INT Elemcount;
/* Hash codes */
typedef unsigned long Hashcode;
/* ------------------------ dynamic arrays ------------------- */
--------------------------------- snip -------------------------------------
2. in lstream.h, removed duplicate declaration of Bytecount.
Rewrote the comment about this type. The changed code should
now look like this:
--------------------------------- snip -------------------------------------
#endif
/* The have been some arguments over the what the type should be that
specifies a count of bytes in a data block to be written out or read in,
using Lstream_read(), Lstream_write(), and related functions.
Originally it was long, which worked fine; Martin "corrected" these to
size_t and ssize_t on the grounds that this is theoretically cleaner and
is in keeping with the C standards. Unfortunately, this practice is
horribly error-prone due to design flaws in the way that mixed
signed/unsigned arithmetic happens. In fact, by doing this change,
Martin introduced a subtle but fatal error that caused the operation of
sending large mail messages to the SMTP server under Windows to fail.
By putting all values back to be signed, avoiding any signed/unsigned
mixing, the bug immediately went away. The type then in use was
Lstream_Data_Count, so that it be reverted cleanly if a vote came to
that. Now it is Bytecount.
Some earlier comments about why the type must be signed: This MUST BE
SIGNED, since it also is used in functions that return the number of
bytes actually read to or written from in an operation, and these
functions can return -1 to signal error.
Note that the standard Unix read() and write() functions define the
count going in as a size_t, which is UNSIGNED, and the count going
out as an ssize_t, which is SIGNED. This is a horrible design
flaw. Not only is it highly likely to lead to logic errors when a
-1 gets interpreted as a large positive number, but operations are
bound to fail in all sorts of horrible ways when a number in the
upper-half of the size_t range is passed in -- this number is
unrepresentable as an ssize_t, so code that checks to see how many
bytes are actually written (which is mandatory if you are dealing
with certain types of devices) will get completely screwed up.
--ben
*/
typedef enum lstream_buffering
--------------------------------- snip -------------------------------------
3. in dumper.c, there are four places, all inside of switch()
statements, where XD_BYTECOUNT appears twice as a case tag. In
each case, the two case blocks contain identical code, and you
should *REMOVE THE SECOND* and leave the first.
| author | ben |
|---|---|
| date | Thu, 20 Sep 2001 06:31:11 +0000 |
| parents | af57a77cbc92 |
| children | 943eaba38521 |
line wrap: on
line diff
--- a/src/redisplay.h Tue Sep 18 05:06:57 2001 +0000 +++ b/src/redisplay.h Thu Sep 20 06:31:11 2001 +0000 @@ -50,7 +50,7 @@ typedef struct line_start_cache line_start_cache; struct line_start_cache { - Bufpos start, end; + Charbpos start, end; int height; }; @@ -112,10 +112,10 @@ each of the face properties in this particular window. */ - Bufpos bufpos; /* buffer position this rune is displaying; + Charbpos charbpos; /* buffer position this rune is displaying; for the modeline, the value here is a Charcount, but who's looking? */ - Bufpos endpos; /* if set this rune covers a range of pos */ + Charbpos endpos; /* if set this rune covers a range of pos */ /* #### Chuck, what does it mean for a rune to cover a range of pos? I don't get this. */ @@ -257,7 +257,7 @@ /* Modeline commentary: IMO the modeline is handled very badly, we special case virtually *everything* in the redisplay routines for - the modeline. The fact that dl->bufpos can be either a buffer + the modeline. The fact that dl->charbpos can be either a buffer position or a char count highlights this. There is no abstraction at all that I can find and it means that the code is made very ugly as a result. Either we should treat the modeline *entirely* separately, @@ -293,9 +293,9 @@ in pixels.*/ unsigned short top_clip; /* amount of top of line to clip in pixels.*/ - Bufpos bufpos; /* first buffer position on line */ - Bufpos end_bufpos; /* last buffer position on line */ - Charcount offset; /* adjustment to bufpos vals */ + Charbpos charbpos; /* first buffer position on line */ + Charbpos end_charbpos; /* last buffer position on line */ + Charcount offset; /* adjustment to charbpos vals */ Charcount num_chars; /* # of chars on line including expansion of tabs and control chars */ @@ -383,13 +383,13 @@ }; /* NOTE NOTE NOTE: Currently the positions in an extent fragment - structure are Bytind's, not Bufpos's. This could change. */ + structure are Bytebpos's, not Charbpos's. This could change. */ struct extent_fragment { Lisp_Object object; /* buffer or string */ struct frame *frm; - Bytind pos, end; + Bytebpos pos, end; EXTENT_dynarr *extents; glyph_block_dynarr *begin_glyphs, *end_glyphs; unsigned int invisible:1; @@ -681,11 +681,11 @@ EXFUN (Fredraw_frame, 2); int redisplay_text_width_string (struct window *w, int findex, - Bufbyte *nonreloc, Lisp_Object reloc, + Intbyte *nonreloc, Lisp_Object reloc, Bytecount offset, Bytecount len); int redisplay_frame_text_width_string (struct frame *f, Lisp_Object face, - Bufbyte *nonreloc, + Intbyte *nonreloc, Lisp_Object reloc, Bytecount offset, Bytecount len); int redisplay_frame (struct frame *f, int preemption_check); @@ -694,9 +694,9 @@ enum display_type type); layout_bounds calculate_display_line_boundaries (struct window *w, int modeline); -Bufpos point_at_center (struct window *w, int type, Bufpos start, - Bufpos point); -int line_at_center (struct window *w, int type, Bufpos start, Bufpos point); +Charbpos point_at_center (struct window *w, int type, Charbpos start, + Charbpos point); +int line_at_center (struct window *w, int type, Charbpos start, Charbpos point); int window_half_pixpos (struct window *w); void redisplay_echo_area (void); void free_display_structs (struct window_mirror *mir); @@ -705,7 +705,7 @@ void generate_displayable_area (struct window *w, Lisp_Object disp_string, int xpos, int ypos, int width, int height, display_line_dynarr* dl, - Bufpos start_pos, face_index default_face); + Charbpos start_pos, face_index default_face); /* `generate_title_string' in frame.c needs this */ void generate_formatted_string_db (Lisp_Object format_str, Lisp_Object result_str, @@ -718,20 +718,20 @@ int pixel_to_glyph_translation (struct frame *f, int x_coord, int y_coord, int *col, int *row, int *obj_x, int *obj_y, - struct window **w, Bufpos *bufpos, - Bufpos *closest, Charcount *modeline_closest, + struct window **w, Charbpos *charbpos, + Charbpos *closest, Charcount *modeline_closest, Lisp_Object *obj1, Lisp_Object *obj2); void glyph_to_pixel_translation (struct window *w, int char_x, int char_y, int *pix_x, int *pix_y); -int point_in_line_start_cache (struct window *w, Bufpos point, +int point_in_line_start_cache (struct window *w, Charbpos point, int min_past); -int point_would_be_visible (struct window *w, Bufpos startp, - Bufpos point); -Bufpos start_of_last_line (struct window *w, Bufpos startp); -Bufpos end_of_last_line (struct window *w, Bufpos startp); -Bufpos start_with_line_at_pixpos (struct window *w, Bufpos point, +int point_would_be_visible (struct window *w, Charbpos startp, + Charbpos point); +Charbpos start_of_last_line (struct window *w, Charbpos startp); +Charbpos end_of_last_line (struct window *w, Charbpos startp); +Charbpos start_with_line_at_pixpos (struct window *w, Charbpos point, int pixpos); -Bufpos start_with_point_on_display_line (struct window *w, Bufpos point, +Charbpos start_with_point_on_display_line (struct window *w, Charbpos point, int line); int redisplay_variable_changed (Lisp_Object sym, Lisp_Object *val, Lisp_Object in_object, int flags); @@ -791,7 +791,7 @@ int last_line, int update_values); void redisplay_output_window (struct window *w); void bevel_modeline (struct window *w, struct display_line *dl); -int redisplay_move_cursor (struct window *w, Bufpos new_point, +int redisplay_move_cursor (struct window *w, Charbpos new_point, int no_output_end); void redisplay_redraw_cursor (struct frame *f, int run_begin_end_meths); void output_display_line (struct window *w, display_line_dynarr *cdla,