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| author | Paul Eggert <eggert@cs.ucla.edu> | 2012-02-03 11:24:22 -0800 |
|---|---|---|
| committer | Paul Eggert <eggert@cs.ucla.edu> | 2012-02-03 11:24:22 -0800 |
| commit | df0b2940c2ac0172d3548829913534d303f9ea45 (patch) | |
| tree | 58695a4f633963199f5663a74f9aa0a82f199706 /src/character.c | |
| parent | 9ff3f0fdc37a4856ef25db649b9b278ebf3683f7 (diff) | |
| download | emacs-df0b2940c2ac0172d3548829913534d303f9ea45.tar.gz emacs-df0b2940c2ac0172d3548829913534d303f9ea45.tar.bz2 emacs-df0b2940c2ac0172d3548829913534d303f9ea45.zip | |
Handle overflow when computing char display width (Bug#9496).
* character.c (char_width): Return EMACS_INT, not int.
(char_width, c_string_width): Check for overflow when
computing the width; this is possible now that individual
characters can have unbounded width. Problem introduced
by merge from Emacs 23 on 2012-01-19.
Diffstat (limited to 'src/character.c')
| -rw-r--r-- | src/character.c | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/src/character.c b/src/character.c index 593fbcece0b..82bc2bfef4e 100644 --- a/src/character.c +++ b/src/character.c @@ -311,10 +311,10 @@ If the multibyte character does not represent a byte, return -1. */) /* Return width (columns) of C considering the buffer display table DP. */ -static int +static EMACS_INT char_width (int c, struct Lisp_Char_Table *dp) { - int width = CHAR_WIDTH (c); + EMACS_INT width = CHAR_WIDTH (c); if (dp) { @@ -326,7 +326,12 @@ char_width (int c, struct Lisp_Char_Table *dp) { ch = AREF (disp, i); if (CHARACTERP (ch)) - width += CHAR_WIDTH (XFASTINT (ch)); + { + int w = CHAR_WIDTH (XFASTINT (ch)); + if (INT_ADD_OVERFLOW (width, w)) + string_overflow (); + width += w; + } } } return width; @@ -340,7 +345,8 @@ Tab is taken to occupy `tab-width' columns. usage: (char-width CHAR) */) (Lisp_Object ch) { - int c, width; + int c; + EMACS_INT width; CHECK_CHARACTER (ch); c = XINT (ch); @@ -367,10 +373,14 @@ c_string_width (const unsigned char *str, EMACS_INT len, int precision, { int bytes; int c = STRING_CHAR_AND_LENGTH (str + i_byte, bytes); - int thiswidth = char_width (c, dp); + EMACS_INT thiswidth = char_width (c, dp); - if (precision > 0 - && (width + thiswidth > precision)) + if (precision <= 0) + { + if (INT_ADD_OVERFLOW (width, thiswidth)) + string_overflow (); + } + else if (precision - width < thiswidth) { *nchars = i; *nbytes = i_byte; |