diff options
Diffstat (limited to 'unix/tkUnixEvent.c')
| -rw-r--r-- | unix/tkUnixEvent.c | 50 |
1 files changed, 40 insertions, 10 deletions
diff --git a/unix/tkUnixEvent.c b/unix/tkUnixEvent.c index eeaa481..de250a1 100644 --- a/unix/tkUnixEvent.c +++ b/unix/tkUnixEvent.c @@ -9,7 +9,7 @@ * See the file "license.terms" for information on usage and redistribution * of this file, and for a DISCLAIMER OF ALL WARRANTIES. * - * RCS: @(#) $Id: tkUnixEvent.c,v 1.11 2003/01/10 20:23:17 jenglish Exp $ + * RCS: @(#) $Id: tkUnixEvent.c,v 1.12 2003/07/02 09:22:45 mdejong Exp $ */ #include "tkInt.h" @@ -29,7 +29,7 @@ static Tcl_ThreadDataKey dataKey; #if defined(TK_USE_INPUT_METHODS) && defined(PEEK_XCLOSEIM) /* * Structure used to peek into internal XIM data structure. - * Enabled only on systems where we are sure it works. + * This is only known to work with XFree86. */ struct XIMPeek { void *junk1, *junk2; @@ -185,17 +185,47 @@ TkpCloseDisplay(dispPtr) #endif if (dispPtr->inputMethod) { /* - * This caused core dumps on some systems (Solaris 2.3 1/6/95). - * The most likely cause of this is a bug in X that accesses - * memory that was already deallocated inside XCloseIM(). - * One can work around this issue by making sure a XDestroyIC() - * gets invoked for each XCreateIC(). + * Calling XCloseIM with an input context that has not + * been freed can cause a crash. This crash has been + * reproduced under Linux systems with XFree86 3.3 + * and may have also been seen under Solaris 2.3. + * The crash is caused by a double free of memory + * inside the X library. Memory that was already + * deallocated may be accessed again inside XCloseIM. + * This bug can be avoided by making sure that a + * call to XDestroyIC is made for each XCreateIC call. + * This bug has been fixed in XFree86 4.2.99.2. + * The internal layout of the XIM structure changed + * in the XFree86 4.2 release so the test should + * not be run for with these new releases. */ #if defined(TK_USE_INPUT_METHODS) && defined(PEEK_XCLOSEIM) - struct XIMPeek *peek = (struct XIMPeek *) dispPtr->inputMethod; - if (peek->ic_chain != NULL) - panic("input contexts not freed before XCloseIM"); + int do_peek = 0; + struct XIMPeek *peek; + + if (strstr(ServerVendor(dispPtr->display), "XFree86")) { + int vendrel = VendorRelease(dispPtr->display); + if (vendrel < 336) { + /* 3.3.4 and 3.3.5 */ + do_peek = 1; + } else if (vendrel < 3900) { + /* Other 3.3.x versions */ + do_peek = 1; + } else if (vendrel < 40000000) { + /* 4.0.x versions */ + do_peek = 1; + } else { + /* Newer than 4.0 */ + do_peek = 0; + } + } + + if (do_peek) { + peek = (struct XIMPeek *) dispPtr->inputMethod; + if (peek->ic_chain != NULL) + panic("input contexts not freed before XCloseIM"); + } #endif XCloseIM(dispPtr->inputMethod); } |