From be2711831fcc4b2282764665de79d0d3c50754e2 Mon Sep 17 00:00:00 2001
From: sebres <info@sebres.de>
Date: Sun, 14 Apr 2024 16:54:34 +0200
Subject: [PATCH] code review, close few mem-leaks (following tcl-core
 [167e0635db79f05d])

---
 generic/tclClock.c    | 28 +++++++++++++++++++++++++---
 generic/tclClockFmt.c | 15 +++++++--------
 generic/tclDate.h     |  1 +
 3 files changed, 33 insertions(+), 11 deletions(-)

diff --git a/generic/tclClock.c b/generic/tclClock.c
index 141ad58..980ff1b 100644
--- a/generic/tclClock.c
+++ b/generic/tclClock.c
@@ -146,6 +146,7 @@ static void		ClockDeleteCmdProc(ClientData);
 static int		ClockSafeCatchCmd(
 			    ClientData clientData, Tcl_Interp *interp,
 			    int objc, Tcl_Obj *const objv[]);
+static void		ClockFinalize(void *);
 /*
  * Structure containing description of "native" clock commands to create.
  */
@@ -212,6 +213,15 @@ TclClockInit(
     ClockClientData *data;
     int i;
 
+    static int initialized = 0;	/* global clock engine initialized (in process) */
+    /*
+     * Register handler to finalize clock on exit.
+     */
+    if (!initialized) {
+	Tcl_CreateExitHandler(ClockFinalize, NULL);
+	initialized = 1;
+    }
+
     /*
      * Safe interps get [::clock] as alias to a master, so do not need their
      * own copies of the support routines.
@@ -378,12 +388,14 @@ ClockDeleteCmdProc(
 	    for (i = 0; i < MCLIT__END; ++i) {
 		Tcl_DecrRefCount(data->mcLiterals[i]);
 	    }
+	    ckfree(data->mcLiterals);
 	    data->mcLiterals = NULL;
 	}
 	if (data->mcLitIdxs != NULL) {
 	    for (i = 0; i < MCLIT__END; ++i) {
 		Tcl_DecrRefCount(data->mcLitIdxs[i]);
 	    }
+	    ckfree(data->mcLitIdxs);
 	    data->mcLitIdxs = NULL;
 	}
 
@@ -4659,12 +4671,11 @@ ClockSafeCatchCmd(
  *
  *----------------------------------------------------------------------
  */
-
+static char* tzWas = INT2PTR(-1);	 /* Previous value of TZ, protected by
+					  * clockMutex. */
 static size_t
 TzsetIfNecessary(void)
 {
-    static char* tzWas = INT2PTR(-1);	 /* Previous value of TZ, protected by
-					  * clockMutex. */
     static long	 tzLastRefresh = 0;	 /* Used for latency before next refresh */
     static size_t tzWasEpoch = 0;        /* Epoch, signals that TZ changed */
     static size_t tzEnvEpoch = 0;        /* Last env epoch, for faster signaling,
@@ -4711,6 +4722,17 @@ TzsetIfNecessary(void)
     return tzWasEpoch;
 }
 
+static void
+ClockFinalize(
+    ClientData clientData)
+{
+    ClockFrmScnFinalize();
+
+    if (tzWas && tzWas != INT2PTR(-1)) {
+	ckfree(tzWas);
+    }
+}
+
 /*
  * Local Variables:
  * mode: c
diff --git a/generic/tclClockFmt.c b/generic/tclClockFmt.c
index 99a6c70..e420fba 100644
--- a/generic/tclClockFmt.c
+++ b/generic/tclClockFmt.c
@@ -32,8 +32,6 @@ TCL_DECLARE_MUTEX(ClockFmtMutex); /* Serializes access to common format list. */
 
 static void ClockFmtScnStorageDelete(ClockFmtScnStorage *fss);
 
-static void ClockFrmScnFinalize(ClientData clientData);
-
 /*
  * Clock scan and format facilities.
  */
@@ -642,7 +640,7 @@ ClockFmtObj_FreeInternalRep(objPtr)
     Tcl_Obj *objPtr;
 {
     ClockFmtScnStorage *fss = ObjClockFmtScn(objPtr);
-    if (fss != NULL) {
+    if (fss != NULL && initialized) {
 	Tcl_MutexLock(&ClockFmtMutex);
 	/* decrement object reference count of format/scan storage */
 	if (--fss->objRefCount <= 0) {
@@ -796,7 +794,6 @@ FindOrCreateFmtScnStorage(
 	    &ClockFmtScnStorageHashKeyType);
 
 	initialized = 1;
-	Tcl_CreateExitHandler(ClockFrmScnFinalize, NULL);
     }
 
     /* get or create entry (and alocate storage) */
@@ -3443,10 +3440,12 @@ ClockFrmScnClearCaches(void)
     Tcl_MutexUnlock(&ClockFmtMutex);
 }
 
-static void
-ClockFrmScnFinalize(
-    ClientData clientData)  /* Not used. */
+void
+ClockFrmScnFinalize()
 {
+    if (!initialized) {
+	return;
+    }
     Tcl_MutexLock(&ClockFmtMutex);
 #if CLOCK_FMT_SCN_STORAGE_GC_SIZE > 0
     /* clear GC */
@@ -3455,8 +3454,8 @@ ClockFrmScnFinalize(
     ClockFmtScnStorage_GC.count = 0;
 #endif
     if (initialized) {
-	Tcl_DeleteHashTable(&FmtScnHashTable);
 	initialized = 0;
+	Tcl_DeleteHashTable(&FmtScnHashTable);
     }
     Tcl_MutexUnlock(&ClockFmtMutex);
     Tcl_MutexFinalize(&ClockFmtMutex);
diff --git a/generic/tclDate.h b/generic/tclDate.h
index f4ae511..a77ea95 100644
--- a/generic/tclDate.h
+++ b/generic/tclDate.h
@@ -606,5 +606,6 @@ MODULE_SCOPE int    ClockFormat(register DateFormat *dateFmt,
 			ClockFmtScnCmdArgs *opts);
 
 MODULE_SCOPE void   ClockFrmScnClearCaches(void);
+MODULE_SCOPE void   ClockFrmScnFinalize();
 
 #endif /* _TCLCLOCK_H */