TIP#100 implementation largely based on work by Georgios Petasis.

3 files changed, 345 insertions, 5 deletions

diff --git a/unix/dltest/Makefile.in b/unix/dltest/Makefile.in
index bd30298..953ed18 100644
--- a/unix/dltest/Makefile.in
+++ b/unix/dltest/Makefile.in
@@ -1,7 +1,7 @@
 # This Makefile is used to create several test cases for Tcl's load
 # command.  It also illustrates how to take advantage of configuration
 # exported by Tcl to set up Makefiles for shared libraries.
-# RCS: @(#) $Id: Makefile.in,v 1.12 2003/04/03 22:13:00 mdejong Exp $
+# RCS: @(#) $Id: Makefile.in,v 1.13 2004/02/24 22:58:48 dkf Exp $
 
 TCL_DBGX =		@TCL_DBGX@
 CC = @CC@
@@ -21,7 +21,7 @@ CFLAGS = @CFLAGS@ @CFLAGS_DEFAULT@
 CC_SWITCHES = $(CFLAGS) -I${SRC_DIR}/../../generic -DTCL_MEM_DEBUG \
 	${SHLIB_CFLAGS} -DUSE_TCL_STUBS ${AC_FLAGS}
 
-all: pkga${SHLIB_SUFFIX} pkgb${SHLIB_SUFFIX} pkgc${SHLIB_SUFFIX} pkgd${SHLIB_SUFFIX} pkge${SHLIB_SUFFIX}
+all: pkga${SHLIB_SUFFIX} pkgb${SHLIB_SUFFIX} pkgc${SHLIB_SUFFIX} pkgd${SHLIB_SUFFIX} pkge${SHLIB_SUFFIX} pkgua${SHLIB_SUFFIX}
 	@touch ../dltest.marker
 
 pkga${SHLIB_SUFFIX}: $(SRC_DIR)/pkga.c
@@ -44,6 +44,10 @@ pkge${SHLIB_SUFFIX}: $(SRC_DIR)/pkge.c
 	$(CC) -c $(CC_SWITCHES) $(SRC_DIR)/pkge.c
 	${SHLIB_LD} -o pkge${SHLIB_SUFFIX} pkge.o ${SHLIB_LD_LIBS}
 
+pkgua${SHLIB_SUFFIX}: $(SRC_DIR)/pkgua.c
+	$(CC) -c $(CC_SWITCHES) $(SRC_DIR)/pkgua.c
+	${SHLIB_LD} -o pkgua${SHLIB_SUFFIX} pkgua.o ${SHLIB_LD_LIBS}
+
 clean:
 	rm -f *.o *${SHLIB_SUFFIX} config.cache config.log config.status
 	rm -f lib.exp ../dltest.marker
diff --git a/unix/dltest/README b/unix/dltest/README
index 12aa8be..3d85a9c 100644
--- a/unix/dltest/README
+++ b/unix/dltest/README
@@ -1,6 +1,6 @@
 This directory contains several files for testing Tcl's dynamic
-loading capabilities.  If shared libraries are supported then
-the build system in the parent directory will create
+loading/unloading capabilities.  If shared libraries are supported
+then the build system in the parent directory will create
 the shared libs and load them into the tcltest executable.
 
-RCS: @(#) $Id: README,v 1.3 2001/12/19 11:03:20 mdejong Exp $
+RCS: @(#) $Id: README,v 1.4 2004/02/24 22:58:48 dkf Exp $
diff --git a/unix/dltest/pkgua.c b/unix/dltest/pkgua.c
new file mode 100644
index 0000000..b4c9b6d
--- /dev/null
+++ b/unix/dltest/pkgua.c
@@ -0,0 +1,336 @@
+/* 
+ * pkgua.c --
+ *
+ *	This file contains a simple Tcl package "pkgua" that is intended
+ *	for testing the Tcl dynamic unloading facilities.
+ *
+ * Copyright (c) 1995 Sun Microsystems, Inc.
+ * Copyright (c) 2004 Georgios Petasis
+ *
+ * See the file "license.terms" for information on usage and redistribution
+ * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ *
+ * RCS: @(#) $Id: pkgua.c,v 1.1 2004/02/24 22:58:48 dkf Exp $
+ */
+
+#include "tcl.h"
+
+/*
+ * Prototypes for procedures defined later in this file:
+ */
+
+static int    PkguaEqObjCmd _ANSI_ARGS_((ClientData clientData,
+		Tcl_Interp *interp, int objc, Tcl_Obj * CONST objv[]));
+static int    PkguaQuoteObjCmd _ANSI_ARGS_((ClientData clientData,
+		Tcl_Interp *interp, int objc, Tcl_Obj * CONST objv[]));
+
+/*
+ * In the following hash table we are going to store a struct that
+ * holds all the command tokens created by Tcl_CreateObjCommand in an
+ * interpreter, indexed by the interpreter. In this way, we can find
+ * which command tokens we have registered in a specific interpreter,
+ * in order to unload them. We need to keep the various command tokens
+ * we have registered, as they are the only safe way to unregister our
+ * registered commands, even if they have been renamed.
+ *
+ * Note that this code is utterly single-threaded.
+ */
+
+static Tcl_HashTable interpTokenMap;
+static int interpTokenMapInitialised = 0;
+#define MAX_REGISTERED_COMMANDS 2
+
+
+static int
+PkguaInitTokensHashTable(void)
+{
+    if (interpTokenMapInitialised) {
+	return;
+    }
+    Tcl_InitHashTable(&interpTokenMap, TCL_ONE_WORD_KEYS);
+    interpTokenMapInitialised = 1;
+};
+
+static int
+PkguaFreeTokensHashTable(void)
+{
+    Tcl_HashSearch search;
+    Tcl_HashEntry *entryPtr;
+
+    for (entryPtr = Tcl_FirstHashEntry(&interpTokenMap, &search);
+	    entryPtr != NULL; entryPtr = Tcl_NextHashEntry(&search)) {
+	Tcl_Free((char *) Tcl_GetHashValue(entryPtr));
+    }
+    interpTokenMapInitialised = 0;
+};
+
+static Tcl_Command *
+PkguaInterpToTokens(interp)
+    Tcl_Interp *interp;
+{
+    int newEntry;
+    Tcl_Command *cmdTokens;
+    Tcl_HashEntry *entryPtr =
+	    Tcl_CreateHashEntry(&interpTokenMap, (char *) interp, &newEntry);
+
+    if (newEntry) {
+	cmdTokens = (Tcl_Command *)
+		Tcl_Alloc(sizeof(Tcl_Command) * (MAX_REGISTERED_COMMANDS+1));
+	for (newEntry=0 ; newEntry<MAX_REGISTERED_COMMANDS+1 ; ++newEntry) {
+	    cmdTokens[newEntry] = NULL;
+	}
+	Tcl_SetHashValue(entryPtr, (ClientData) cmdTokens);
+    } else {
+	cmdTokens = (Tcl_Command *) Tcl_GetHashValue(entryPtr);
+    }
+    return cmdTokens;
+};
+
+static void
+PkguaDeleteTokens(interp)
+    Tcl_Interp *interp;
+{
+    Tcl_HashEntry *entryPtr =
+	    Tcl_FindHashEntry(&interpTokenMap, (char *) interp);
+
+    if (entryPtr) {
+	Tcl_Free((char *) Tcl_GetHashValue(entryPtr));
+	Tcl_DeleteHashEntry(entryPtr);
+    }
+};
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * PkguaEqObjCmd --
+ *
+ *	This procedure is invoked to process the "pkgua_eq" Tcl command.
+ *	It expects two arguments and returns 1 if they are the same,
+ *	0 if they are different.
+ *
+ * Results:
+ *	A standard Tcl result.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+PkguaEqObjCmd(dummy, interp, objc, objv)
+    ClientData dummy;		/* Not used. */
+    Tcl_Interp *interp;		/* Current interpreter. */
+    int objc;			/* Number of arguments. */
+    Tcl_Obj * CONST objv[];	/* Argument objects. */
+{
+    int result;
+    CONST char *str1, *str2;
+    int len1, len2, n;
+
+    if (objc != 3) {
+	Tcl_WrongNumArgs(interp, 1, objv,  "string1 string2");
+	return TCL_ERROR;
+    }
+
+    str1 = Tcl_GetStringFromObj(objv[1], &len1);
+    str2 = Tcl_GetStringFromObj(objv[2], &len2);
+    if (len1 == len2) {
+	result = (Tcl_UtfNcmp(str1, str2, len1) == 0);
+    } else {
+	result = 0;
+    }
+    Tcl_SetObjResult(interp, Tcl_NewIntObj(result));
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * PkguaQuoteObjCmd --
+ *
+ *	This procedure is invoked to process the "pkgua_quote" Tcl command.
+ *	It expects one argument, which it returns as result.
+ *
+ * Results:
+ *	A standard Tcl result.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+PkguaQuoteObjCmd(dummy, interp, objc, objv)
+    ClientData dummy;		/* Not used. */
+    Tcl_Interp *interp;		/* Current interpreter. */
+    int objc;			/* Number of arguments. */
+    Tcl_Obj * CONST objv[];	/* Argument strings. */
+{
+    if (objc != 2) {
+	Tcl_WrongNumArgs(interp, 1, objv, "value");
+	return TCL_ERROR;
+    }
+    Tcl_SetObjResult(interp, objv[1]);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Pkgua_Init --
+ *
+ *	This is a package initialization procedure, which is called
+ *	by Tcl when this package is to be added to an interpreter.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+Pkgua_Init(interp)
+    Tcl_Interp *interp;		/* Interpreter in which the package is
+				 * to be made available. */
+{
+    int code, cmdIndex = 0;
+    Tcl_Command *cmdTokens;
+
+    if (Tcl_InitStubs(interp, TCL_VERSION, 0) == NULL) {
+	return TCL_ERROR;
+    }
+
+    /*
+     * Initialise our Hash table, where we store the registered
+     * command tokens for each interpreter.
+     */
+
+    PkguaInitTokensHashTable();
+
+    code = Tcl_PkgProvide(interp, "Pkgua", "1.0");
+    if (code != TCL_OK) {
+	return code;
+    }
+
+    Tcl_SetVar(interp, "::pkgua_loaded", ".", TCL_APPEND_VALUE);
+
+    cmdTokens = PkguaInterpToTokens(interp);
+    cmdTokens[cmdIndex++] =
+	Tcl_CreateObjCommand(interp, "pkgua_eq", PkguaEqObjCmd,
+			     (ClientData) 0, (Tcl_CmdDeleteProc *) NULL);
+    cmdTokens[cmdIndex++] =
+	Tcl_CreateObjCommand(interp, "pkgua_quote", PkguaQuoteObjCmd,
+			     (ClientData) 0, (Tcl_CmdDeleteProc *) NULL);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Pkgua_SafeInit --
+ *
+ *	This is a package initialization procedure, which is called
+ *	by Tcl when this package is to be added to an unsafe interpreter.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+Pkgua_SafeInit(interp)
+    Tcl_Interp *interp;		/* Interpreter in which the package is
+				 * to be made available. */
+{
+    return Pkgua_Init(interp);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Pkgua_Unload --
+ *
+ *	This is a package unloading initialization procedure, which is
+ *	called by Tcl when this package is to be unloaded form an
+ *	interpreter.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+Pkgua_Unload(interp, flags)
+    Tcl_Interp *interp;		/* Interpreter from which the package is
+				 * to be unloaded. */
+    int flags;			/* Flags passed by the unloading mechanism */
+{
+    int code, cmdIndex;
+    Tcl_Command *cmdTokens = PkguaInterpToTokens(interp);
+
+    for (cmdIndex=0 ; cmdIndex<MAX_REGISTERED_COMMANDS ; cmdIndex++) {
+	if (cmdTokens[cmdIndex] == NULL) {
+	    continue;
+	}
+	code = Tcl_DeleteCommandFromToken(interp, cmdTokens[cmdIndex]);
+	if (code != TCL_OK) {
+	    return code;
+	}
+    }
+
+    PkguaDeleteTokens(interp);
+
+    Tcl_SetVar(interp, "::pkgua_detached", ".", TCL_APPEND_VALUE);
+
+    if (flags == TCL_UNLOAD_DETACH_FROM_PROCESS) {
+	/*
+	 * Tcl is ready to detach this library from the running
+	 * application. We should free all the memory that is not
+	 * related to any interpreter.
+	 */
+	PkguaFreeTokensHashTable();
+
+	Tcl_SetVar(interp, "::pkgua_unloaded", ".", TCL_APPEND_VALUE);
+    }
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Pkgua_SafeUnload --
+ *
+ *	This is a package unloading initialization procedure, which is
+ *	called by Tcl when this package is to be unloaded form an
+ *	interpreter.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+Pkgua_SafeUnload(interp, flags)
+    Tcl_Interp *interp;		/* Interpreter from which the package is
+				 * to be unloaded. */
+    int flags;			/* Flags passed by the unloading mechanism */
+{
+    return Pkgua_Unload(interp, flags);
+}