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-rw-r--r--generic/tclEnv.c84
1 files changed, 67 insertions, 17 deletions
diff --git a/generic/tclEnv.c b/generic/tclEnv.c
index b5ae6ea..8f51c1b 100644
--- a/generic/tclEnv.c
+++ b/generic/tclEnv.c
@@ -76,36 +76,56 @@ TclSetupEnv(
Tcl_Interp *interp) /* Interpreter whose "env" array is to be
* managed. */
{
+ Var *varPtr, *arrayPtr;
+ Tcl_Obj *varNamePtr;
Tcl_DString envString;
- char *p1, *p2;
- int i;
+ Tcl_HashTable namesHash;
+ Tcl_HashEntry *hPtr;
+ Tcl_HashSearch search;
/*
* Synchronize the values in the environ array with the contents of the
* Tcl "env" variable. To do this:
- * 1) Remove the trace that fires when the "env" var is unset.
- * 2) Unset the "env" variable.
- * 3) If there are no environ variables, create an empty "env" array.
- * Otherwise populate the array with current values.
- * 4) Add a trace that synchronizes the "env" array.
+ * 1) Remove the trace that fires when the "env" var is updated.
+ * 2) Find the existing contents of the "env", storing in a hash table.
+ * 3) Create/update elements for each environ variable, removing
+ * elements from the hash table as we go.
+ * 4) Remove the elements for each remaining entry in the hash table,
+ * which must have existed before yet have no analog in the environ
+ * variable.
+ * 5) Add a trace that synchronizes the "env" array.
*/
Tcl_UntraceVar2(interp, "env", NULL,
TCL_GLOBAL_ONLY | TCL_TRACE_WRITES | TCL_TRACE_UNSETS |
TCL_TRACE_READS | TCL_TRACE_ARRAY, EnvTraceProc, NULL);
- Tcl_UnsetVar2(interp, "env", NULL, TCL_GLOBAL_ONLY);
+ /*
+ * Find out what elements are currently in the global env array.
+ */
- if (environ[0] == NULL) {
- Tcl_Obj *varNamePtr;
+ TclNewLiteralStringObj(varNamePtr, "env");
+ Tcl_IncrRefCount(varNamePtr);
+ Tcl_InitObjHashTable(&namesHash);
+ varPtr = TclObjLookupVarEx(interp, varNamePtr, NULL, TCL_GLOBAL_ONLY,
+ /*msg*/ 0, /*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
+ TclFindArrayPtrElements(varPtr, &namesHash);
+
+ /*
+ * Go through the environment array and transfer its values into Tcl. At
+ * the same time, remove those elements we add/update from the hash table
+ * of existing elements, so that after this part processes, that table
+ * will hold just the parts to remove.
+ */
+
+ if (environ[0] != NULL) {
+ int i;
- TclNewLiteralStringObj(varNamePtr, "env");
- Tcl_IncrRefCount(varNamePtr);
- TclArraySet(interp, varNamePtr, NULL);
- Tcl_DecrRefCount(varNamePtr);
- } else {
Tcl_MutexLock(&envMutex);
for (i = 0; environ[i] != NULL; i++) {
+ Tcl_Obj *obj1, *obj2;
+ char *p1, *p2;
+
p1 = Tcl_ExternalToUtfDString(NULL, environ[i], -1, &envString);
p2 = strchr(p1, '=');
if (p2 == NULL) {
@@ -119,12 +139,41 @@ TclSetupEnv(
}
p2++;
p2[-1] = '\0';
- Tcl_SetVar2(interp, "env", p1, p2, TCL_GLOBAL_ONLY);
+ obj1 = Tcl_NewStringObj(p1, -1);
+ obj2 = Tcl_NewStringObj(p2, -1);
Tcl_DStringFree(&envString);
+
+ Tcl_IncrRefCount(obj1);
+ Tcl_IncrRefCount(obj2);
+ Tcl_ObjSetVar2(interp, varNamePtr, obj1, obj2, TCL_GLOBAL_ONLY);
+ hPtr = Tcl_FindHashEntry(&namesHash, obj1);
+ if (hPtr != NULL) {
+ Tcl_DeleteHashEntry(hPtr);
+ }
+ Tcl_DecrRefCount(obj1);
+ Tcl_DecrRefCount(obj2);
}
Tcl_MutexUnlock(&envMutex);
}
+ /*
+ * Delete those elements that existed in the array but which had no
+ * counterparts in the environment array.
+ */
+
+ for (hPtr=Tcl_FirstHashEntry(&namesHash, &search); hPtr!=NULL;
+ hPtr=Tcl_NextHashEntry(&search)) {
+ Tcl_Obj *elemName = Tcl_GetHashValue(hPtr);
+
+ TclObjUnsetVar2(interp, varNamePtr, elemName, TCL_GLOBAL_ONLY);
+ }
+ Tcl_DeleteHashTable(&namesHash);
+ Tcl_DecrRefCount(varNamePtr);
+
+ /*
+ * Re-establish the trace.
+ */
+
Tcl_TraceVar2(interp, "env", NULL,
TCL_GLOBAL_ONLY | TCL_TRACE_WRITES | TCL_TRACE_UNSETS |
TCL_TRACE_READS | TCL_TRACE_ARRAY, EnvTraceProc, NULL);
@@ -565,7 +614,8 @@ EnvTraceProc(
const char *value = TclGetEnv(name2, &valueString);
if (value == NULL) {
- return (char *) "no such variable";
+ Tcl_UnsetVar2(interp, name1, name2, 0);
+ return NULL;
}
Tcl_SetVar2(interp, name1, name2, value, 0);
Tcl_DStringFree(&valueString);