diff options
Diffstat (limited to 'generic/tclCmdMZ.c')
| -rw-r--r-- | generic/tclCmdMZ.c | 39 |
1 files changed, 31 insertions, 8 deletions
diff --git a/generic/tclCmdMZ.c b/generic/tclCmdMZ.c index 474f90f..e121999 100644 --- a/generic/tclCmdMZ.c +++ b/generic/tclCmdMZ.c @@ -15,7 +15,7 @@ * See the file "license.terms" for information on usage and redistribution of * this file, and for a DISCLAIMER OF ALL WARRANTIES. * - * RCS: @(#) $Id: tclCmdMZ.c,v 1.139 2006/11/09 15:37:55 dkf Exp $ + * RCS: @(#) $Id: tclCmdMZ.c,v 1.140 2006/11/09 16:11:46 dkf Exp $ */ #include "tclInt.h" @@ -2196,7 +2196,7 @@ Tcl_StringObjCmd(dummy, interp, objc, objv) break; } case STR_REVERSE: { - Tcl_UniChar *ustring1, *ustring2; + Tcl_UniChar *ustring1; int i, j; if (objc != 3) { @@ -2205,14 +2205,37 @@ Tcl_StringObjCmd(dummy, interp, objc, objv) } ustring1 = Tcl_GetUnicodeFromObj(objv[2], &length1); - ustring2 = (Tcl_UniChar *) - ckalloc(sizeof(Tcl_UniChar) * (unsigned)length1); + if (Tcl_IsShared(objv[2])) { + Tcl_UniChar *ustring2 = (Tcl_UniChar *) + ckalloc(sizeof(Tcl_UniChar) * (unsigned)length1); + + for (i=0,j=length1-1 ; i<length1 ; i++,j--) { + ustring2[j] = ustring1[i]; + } + Tcl_SetObjResult(interp, Tcl_NewUnicodeObj(ustring2, length1)); + ckfree((char *) ustring2); + } else { + /* + * The object is unshared, so we can do the swap in-place. This + * avoids memory allocation, and so is faster. + */ - for (i=0,j=length1-1 ; i<length1 ; i++,j--) { - ustring2[j] = ustring1[i]; + for (i=0,j=length1-1 ; i<j ; i++,j--) { + Tcl_UniChar tmp = ustring1[i]; + ustring1[i] = ustring1[j]; + ustring1[j] = tmp; + } + + /* + * Tricky. Must invalidate the string (utf-8) representation to + * ensure that it is regenerated from the "unicode" internal rep. + */ + + if (objv[2]->bytes != NULL) { + Tcl_InvalidateStringRep(objv[2]); + } + Tcl_SetObjResult(interp, objv[2]); } - Tcl_SetObjResult(interp, Tcl_NewUnicodeObj(ustring2, length1)); - ckfree((char *) ustring2); break; } case STR_TOLOWER: |