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| author | Paul Eggert <eggert@cs.ucla.edu> | 2011-05-15 22:08:59 -0700 |
|---|---|---|
| committer | Paul Eggert <eggert@cs.ucla.edu> | 2011-05-15 22:08:59 -0700 |
| commit | 2b4560a850d2ea0767d0a3c4db19e4468f61b4eb (patch) | |
| tree | ca99d199897a9289dfff5a1f492341402d79ae69 /src/character.c | |
| parent | cb93f9bef01e95b17b3d7b8786c103505355d98c (diff) | |
| download | emacs-2b4560a850d2ea0767d0a3c4db19e4468f61b4eb.tar.gz | |
* character.c (lisp_string_width): Check for string overflow.
Use EMACS_INT, not int, for string indexes and lengths; in
particular, 2nd arg is now EMACS_INT, not int. Do not crash if
the resulting string length overflows an EMACS_INT; instead,
report a string overflow if no precision given. When checking for
precision exhaustion, use a check that cannot possibly have
integer overflow. (Bug#8675)
* character.h (lisp_string_width): Adjust to new signature.
Diffstat (limited to 'src/character.c')
| -rw-r--r-- | src/character.c | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/src/character.c b/src/character.c index 6a8b86d5d87..a03c081a716 100644 --- a/src/character.c +++ b/src/character.c @@ -35,6 +35,7 @@ along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */ #include <sys/types.h> #include <setjmp.h> +#include <intprops.h> #include "lisp.h" #include "character.h" #include "buffer.h" @@ -404,7 +405,7 @@ strwidth (const char *str, EMACS_INT len) in *NCHARS and *NBYTES respectively. */ EMACS_INT -lisp_string_width (Lisp_Object string, int precision, +lisp_string_width (Lisp_Object string, EMACS_INT precision, EMACS_INT *nchars, EMACS_INT *nbytes) { EMACS_INT len = SCHARS (string); @@ -419,7 +420,7 @@ lisp_string_width (Lisp_Object string, int precision, while (i < len) { - int chars, bytes, thiswidth; + EMACS_INT chars, bytes, thiswidth; Lisp_Object val; int cmp_id; EMACS_INT ignore, end; @@ -437,7 +438,11 @@ lisp_string_width (Lisp_Object string, int precision, int c; if (multibyte) - c = STRING_CHAR_AND_LENGTH (str + i_byte, bytes); + { + int cbytes; + c = STRING_CHAR_AND_LENGTH (str + i_byte, cbytes); + bytes = cbytes; + } else c = str[i_byte], bytes = 1; chars = 1; @@ -455,8 +460,14 @@ lisp_string_width (Lisp_Object string, int precision, } } - if (precision > 0 - && (width + thiswidth > precision)) + if (precision <= 0) + { +#ifdef emacs + if (INT_ADD_OVERFLOW (width, thiswidth)) + string_overflow (); +#endif + } + else if (precision - width < thiswidth) { *nchars = i; *nbytes = i_byte; |