Simplify TIP #414 implementation by using the function TclInitStubTable() in stead of re-use Tcl_InitStubs().

5 files changed, 89 insertions, 8 deletions

diff --git a/doc/InitSubSyst.3 b/doc/InitSubSyst.3
new file mode 100644
index 0000000..08b3154
--- /dev/null
+++ b/doc/InitSubSyst.3
@@ -0,0 +1,53 @@
+'\"
+'\" Copyright (c) 2013 Tcl Core Team
+'\"
+'\" See the file "license.terms" for information on usage and redistribution
+'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+'\" 
+.so man.macros
+.TH Tcl_InitSubsystems 3 8.6.1 Tcl "Tcl Library Procedures"
+.BS
+.SH NAME
+Tcl_InitSubsystems \- initialize the Tcl library.
+.SH SYNOPSIS
+.nf
+\fB#include <tcl.h>\fR
+.sp
+const char *
+\fBTcl_InitSubsystems\fR(\fIpanicProc\fR)
+.SH ARGUMENTS
+.SH ARGUMENTS
+.AS Tcl_PanicProc *panicProc
+.AP Tcl_PanicProc *panicProc in
+Desired panic function, for error reporting. If NULL, the default
+panicProc is used, which normally writes the message to stderr.
+.BE
+
+.SH DESCRIPTION
+.PP
+The \fBTcl_InitSubsystems\fR procedure initializes the Tcl
+library. This procedure is typically invoked as the very
+first thing in the application's main program.
+.PP
+\fBTcl_InitSubsystems\fR is very similar in use to
+\fBTcl_FindExecutable\fR. It can be used when Tcl is
+used as utility library, no other encodings than utf8,
+iso8859-1 or unicode are used, and no interest exists in the
+value of \fBinfo nameofexecutable\fR. The system encoding will not
+be extracted from the environment, but falls back to iso8859-1.
+.PP
+The return value is the Tcl version.
+.PP
+If \fBTcl_InitSubsystems()\fR is called in code where 
+\fBUSE_TCL_STUBS\fR is set, it does one additional thing:
+initialize the Stub table for using Tcl as utility
+library, without needing a Tcl interpreter. For example:
+.CS
+const char *version = Tcl_InitSubSystems(NULL);
+/* At this point, Tcl C API calls without interp are ready for use */
+int major, minor, patch;
+Tcl_GetVersion(&major, &minor, &patch);
+.CE
+This will work as expected, both with and without stubs.
+.SH KEYWORDS
+binary, executable file
diff --git a/generic/tcl.h b/generic/tcl.h
index d47e931..739966c 100644
--- a/generic/tcl.h
+++ b/generic/tcl.h
@@ -2397,6 +2397,8 @@ const char *		Tcl_InitStubs(Tcl_Interp *interp, const char *version,
 			    int exact);
 const char *		TclTomMathInitializeStubs(Tcl_Interp *interp,
 			    const char *version, int epoch, int revision);
+const char *		TclInitStubTable(const char *version);
+
 
 /*
  * When not using stubs, make it a macro.
@@ -2411,13 +2413,21 @@ const char *		TclTomMathInitializeStubs(Tcl_Interp *interp,
  * TODO - tommath stubs export goes here!
  */
 
+/* Tcl_InitSubsystems, see TIP #414 */
+
+EXTERN const char *Tcl_InitSubsystems(Tcl_PanicProc *panicProc);
+#ifdef USE_TCL_STUBS
+#define Tcl_InitSubsystems(panicProc) \
+    TclInitStubTable((Tcl_InitSubsystems)(panicProc))
+#endif
+
 /*
  * Public functions that are not accessible via the stubs table.
  * Tcl_GetMemoryInfo is needed for AOLserver. [Bug 1868171]
  */
 
 #define Tcl_Main(argc, argv, proc) Tcl_MainEx(argc, argv, proc, \
-	    (Tcl_FindExecutable(argv[0]), (Tcl_CreateInterp)()))
+	    (Tcl_InitSubsystems(NULL), Tcl_CreateInterp()))
 EXTERN void		Tcl_MainEx(int argc, char **argv,
 			    Tcl_AppInitProc *appInitProc, Tcl_Interp *interp);
 EXTERN const char *	Tcl_PkgInitStubsCheck(Tcl_Interp *interp,
diff --git a/generic/tclEncoding.c b/generic/tclEncoding.c
index 2cc55d6..b94e355 100644
--- a/generic/tclEncoding.c
+++ b/generic/tclEncoding.c
@@ -1411,21 +1411,40 @@ Tcl_UtfToExternal(
 /*
  *---------------------------------------------------------------------------
  *
- * Tcl_FindExecutable --
+ * Tcl_InitSubsystems/Tcl_FindExecutable --
  *
- *	This function computes the absolute path name of the current
- *	application, given its argv[0] value.
+ *	This function initializes everything needed for the Tcl library
+ *	to be able to operate.
  *
  * Results:
  *	None.
  *
  * Side effects:
  *	The absolute pathname for the application is computed and stored to be
- *	returned later be [info nameofexecutable].
+ *	returned later by [info nameofexecutable]. The system encoding is
+ *	determined and stored to be returned later by [encoding system]
  *
  *---------------------------------------------------------------------------
  */
+MODULE_SCOPE const TclStubs tclStubs;
+
+/* Structure returned by Tcl_InitSubsystems, which can be interpreted
+ * as the Tcl version, but also can be used to initialize the stub table. */
+static const TclStubInfoType stubInfo = {
+    TCL_PATCH_LEVEL, (ClientData) &tclStubs
+};
+
 #undef Tcl_FindExecutable
+const char *
+Tcl_InitSubsystems(Tcl_PanicProc *panicProc)
+{
+    if (panicProc) {
+	Tcl_SetPanicProc(panicProc);
+    }
+    TclInitSubsystems();
+    return stubInfo.version;
+}
+
 void
 Tcl_FindExecutable(
     const char *argv0)		/* The value of the application's argv[0]
diff --git a/generic/tclInt.h b/generic/tclInt.h
index 3432b37..346fa96 100644
--- a/generic/tclInt.h
+++ b/generic/tclInt.h
@@ -3840,8 +3840,6 @@ typedef struct {
     ClientData data;
 } TclStubInfoType;
 
-MODULE_SCOPE const char *TclInitStubTable(const char *version);
-
 /*
  * Functions defined in generic/tclVar.c and currenttly exported only for use
  * by the bytecode compiler and engine. Some of these could later be placed in
diff --git a/generic/tclMain.c b/generic/tclMain.c
index f445383..7a31d43 100644
--- a/generic/tclMain.c
+++ b/generic/tclMain.c
@@ -313,6 +313,8 @@ Tcl_MainEx(
     Tcl_Channel chan;
     InteractiveState is;
 
+    TclpSetInitialEncodings();
+    TclpFindExecutable((void *)argv[0]);
     Tcl_InitMemory(interp);
 
     is.interp = interp;
@@ -640,7 +642,6 @@ Tcl_Main(
 				 * function to call after most initialization
 				 * but before starting to execute commands. */
 {
-    Tcl_FindExecutable(argv[0]);
     Tcl_MainEx(argc, argv, appInitProc, Tcl_CreateInterp());
 }
 #endif /* TCL_MAJOR_VERSION == 8 && !UNICODE */