Revise Tcl_InitStringRep(); numBytes is unsigned. Only truncation permitted.

3 files changed, 16 insertions, 14 deletions

diff --git a/generic/tcl.decls b/generic/tcl.decls
index 24484a5..2bb49b9 100644
--- a/generic/tcl.decls
+++ b/generic/tcl.decls
@@ -2331,7 +2331,8 @@ declare 631 {
     void Tcl_FreeIntRep(Tcl_Obj *objPtr)
 }
 declare 632 {
-    char *Tcl_InitStringRep(Tcl_Obj *objPtr, const char *bytes, int numBytes)
+    char *Tcl_InitStringRep(Tcl_Obj *objPtr, const char *bytes,
+	    unsigned int numBytes)
 }
 
 # ----- BASELINE -- FOR -- 8.7.0 ----- #
diff --git a/generic/tclDecls.h b/generic/tclDecls.h
index 3e2ac18..7114ad9 100644
--- a/generic/tclDecls.h
+++ b/generic/tclDecls.h
@@ -1820,7 +1820,7 @@ EXTERN void		Tcl_ZlibStreamSetCompressionDictionary(
 EXTERN void		Tcl_FreeIntRep(Tcl_Obj *objPtr);
 /* 632 */
 EXTERN char *		Tcl_InitStringRep(Tcl_Obj *objPtr, const char *bytes,
-				int numBytes);
+				unsigned int numBytes);
 
 typedef struct {
     const struct TclPlatStubs *tclPlatStubs;
@@ -2488,7 +2488,7 @@ typedef struct TclStubs {
     int (*tcl_FSUnloadFile) (Tcl_Interp *interp, Tcl_LoadHandle handlePtr); /* 629 */
     void (*tcl_ZlibStreamSetCompressionDictionary) (Tcl_ZlibStream zhandle, Tcl_Obj *compressionDictionaryObj); /* 630 */
     void (*tcl_FreeIntRep) (Tcl_Obj *objPtr); /* 631 */
-    char * (*tcl_InitStringRep) (Tcl_Obj *objPtr, const char *bytes, int numBytes); /* 632 */
+    char * (*tcl_InitStringRep) (Tcl_Obj *objPtr, const char *bytes, unsigned int numBytes); /* 632 */
 } TclStubs;
 
 extern const TclStubs *tclStubsPtr;
diff --git a/generic/tclObj.c b/generic/tclObj.c
index 72c2340..3fb344e 100644
--- a/generic/tclObj.c
+++ b/generic/tclObj.c
@@ -1746,22 +1746,24 @@ char *
 Tcl_InitStringRep(
     Tcl_Obj *objPtr,	/* Object whose string rep is to be set */
     const char *bytes,
-    int numBytes)
+    unsigned int numBytes)
 {
-    assert(numBytes >= 0);
-
     assert(objPtr->bytes == NULL || bytes == NULL);
 
+    if (numBytes > INT_MAX) {
+	Tcl_Panic("max size for a Tcl value (%d bytes) exceeded", INT_MAX);
+    }
+
     /* Allocate */
     if (objPtr->bytes == NULL) {
 	/* Allocate only as empty - extend later if bytes copied */
 	objPtr->length = 0;
 	if (numBytes) {
-	    objPtr->bytes = (char *)ckalloc((unsigned)(numBytes+1));
+	    objPtr->bytes = (char *)ckalloc(numBytes+1);
 	    if (bytes) {
 		/* Copy */
-		memcpy(objPtr->bytes, bytes, (unsigned) numBytes);
-		objPtr->length = numBytes;
+		memcpy(objPtr->bytes, bytes, numBytes);
+		objPtr->length = (int) numBytes;
 	    }
 	} else {
 	    objPtr->bytes = tclEmptyStringRep;
@@ -1769,12 +1771,11 @@ Tcl_InitStringRep(
 	}
     } else {
 	/* objPtr->bytes != NULL bytes == NULL - Truncate */
-	assert(numBytes <= objPtr->length);
-	if (objPtr->length > numBytes) {
-	    objPtr->bytes = (char *)ckrealloc(objPtr->bytes,
-		    (unsigned)(numBytes+1));
+	assert((int)numBytes <= objPtr->length);
+	if (objPtr->length > (int)numBytes) {
+	    objPtr->bytes = (char *)ckrealloc(objPtr->bytes, numBytes+1);
+	    objPtr->length = (int)numBytes;
 	}
-	objPtr->length = numBytes;
     }
 
     /* Terminate */