17384: new recursive-edit widget.

ChangeLog

@@ -1,3 +1,9 @@
+2002-07-01  Peter Stephenson  <pws@csr.com>
+
+	* 17384: Src/Zle/zle_main.c, Src/Zle/iwidgets.list,
+	Doc/Zsh/zle.yo: new `recursive-edit' widget allows a user-defined
+	widget to pass control back to zle as a subcommand.
+
 2002-07-01  Sven Wischnowsky  <wischnow@zsh.org>
 
 	* 17387: Completion/Zsh/Context/.distfiles,

Doc/Zsh/zle.yo

@@ -1620,6 +1620,48 @@ At a secondary (tt(PS2)) prompt, move the entire current multiline
 construct into the editor buffer.
 The latter is equivalent to tt(push-input) followed by tt(get-line).
 )
+tindex(recursive-edit)
+item(tt(recursive-edit))(
+Only useful from a user-defined widget.  At this point in the function,
+the editor regains control until one of the standard widgets which would
+normally cause zle to exit (typically an tt(accept-line) caused by
+hitting the return key) is executed.  Instead, control returns to the
+user-defined widget.  The status returned is non-zero if the return was
+caused by an error, but the function still continues executing and hence
+may tidy up.  This makes it safe for the user-defined widget to alter
+the command line or key bindings temporarily.
+
+
+The following widget, tt(caps-lock), serves as an example.
+example(self-insert-ucase() {
+  LBUFFER+=${(U)KEYS[-1]}
+}
+
+integer stat
+
+zle -N self-insert self-insert-ucase
+zle -A caps-lock save-caps-lock
+zle -A accept-line caps-lock
+
+zle recursive-edit
+stat=$?
+
+zle -A .self-insert self-insert
+zle -A save-caps-lock caps-lock
+zle -D save-caps-lock
+
+(( stat )) && zle send-break
+
+return $stat
+)
+This causes typed letters to be inserted capitalised until either
+tt(accept-line) (i.e. typically the return key) is typed or the
+tt(caps-lock) widget is invoked again; the later is handled by saving
+the old definition of tt(caps-lock) as tt(save-caps-lock) and then
+rebinding it to invoke tt(accept-line).  Note that an error from the
+recursive edit is detected as a non-zero return status and propagated by
+using the tt(send-break) widget.
+)
 tindex(redisplay)
 item(tt(redisplay) (unbound) (^R) (^R))(
 Redisplays the edit buffer.

Src/Zle/iwidgets.list

@@ -85,6 +85,7 @@
 "quoted-insert", quotedinsert, ZLE_MENUCMP | ZLE_KEEPSUFFIX
 "quote-line", quoteline, 0
 "quote-region", quoteregion, 0
+"recursive-edit", recursiveedit, ZLE_MENUCMP | ZLE_KEEPSUFFIX | ZLE_LASTCOL
 "redisplay", redisplay, ZLE_MENUCMP | ZLE_KEEPSUFFIX | ZLE_LASTCOL
 "redo", redo, ZLE_KEEPSUFFIX
 "reverse-menu-complete", reversemenucomplete, ZLE_MENUCMP | ZLE_KEEPSUFFIX | ZLE_ISCOMP

Src/Zle/zle_main.c

@@ -89,10 +89,11 @@ mod_export int eofchar;
 static int eofsent;
 static long keytimeout;
 
-#ifdef HAVE_SELECT
+#if defined(HAVE_SELECT) || defined(HAVE_POLL)
 /* Terminal baud rate */
 
 static int baud;
+static long costmult;
 #endif
 
 /* flags associated with last command */
@@ -631,108 +632,19 @@ getkey(int keytmout)
     return ret;
 }
 
-/* Read a line.  It is returned metafied. */
-
 /**/
-unsigned char *
+void
-zleread(char *lp, char *rp, int flags)
+zlecore(void)
 {
-    unsigned char *s;
+#if !defined(HAVE_POLL) && defined(HAVE_SELECT)
-    int old_errno = errno;
-    int tmout = getiparam("TMOUT");
-
-#if defined(HAVE_SELECT) || defined(HAVE_POLL)
-    long costmult;
-# ifdef HAVE_POLL
-# else
     struct timeval tv;
     fd_set foofd;
-# endif
 
-    baud = getiparam("BAUD");
-    costmult = (baud) ? 3840000L / baud : 0;
-#endif
-
-    /* ZLE doesn't currently work recursively.  This is needed in case a *
-     * select loop is used in a function called from ZLE.  vared handles *
-     * this differently itself.                                          */
-    if(zleactive) {
-	char *pptbuf;
-	int pptlen;
-
-	pptbuf = unmetafy(promptexpand(lp, 0, NULL, NULL), &pptlen);
-	write(2, (WRITE_ARG_2_T)pptbuf, pptlen);
-	free(pptbuf);
-	return (unsigned char *)shingetline();
-    }
-
-    keytimeout = getiparam("KEYTIMEOUT");
-    if (!shout) {
-	if (SHTTY != -1)
-	    init_shout();
-
-	if (!shout)
-	    return NULL;
-	/* We could be smarter and default to a system read. */
-
-	/* If we just got a new shout, make sure the terminal is set up. */
-	if (termflags & TERM_UNKNOWN)
-	    init_term();
-    }
-
-    fflush(shout);
-    fflush(stderr);
-    intr();
-    insmode = unset(OVERSTRIKE);
-    eofsent = 0;
-    resetneeded = 0;
-    lpromptbuf = promptexpand(lp, 1, NULL, NULL);
-    pmpt_attr = txtchange;
-    rpromptbuf = promptexpand(rp, 1, NULL, NULL);
-    rpmpt_attr = txtchange;
-
-    zlereadflags = flags;
-    histline = curhist;
-#ifndef HAVE_POLL
-# ifdef HAVE_SELECT
     FD_ZERO(&foofd);
-# endif
 #endif
-    undoing = 1;
+
-    line = (unsigned char *)zalloc((linesz = 256) + 2);
-    virangeflag = lastcmd = done = cs = ll = mark = 0;
-    vichgflag = 0;
-    viinsbegin = 0;
-    statusline = NULL;
-    selectkeymap("main", 1);
-    selectlocalmap(NULL);
-    fixsuffix();
-    if ((s = (unsigned char *)getlinknode(bufstack))) {
-	setline((char *)s);
-	zsfree((char *)s);
-	if (stackcs != -1) {
-	    cs = stackcs;
-	    stackcs = -1;
-	    if (cs > ll)
-		cs = ll;
-	}
-	if (stackhist != -1) {
-	    histline = stackhist;
-	    stackhist = -1;
-	}
-    }
-    initundo();
-    if (isset(PROMPTCR))
-	putc('\r', shout);
-    if (tmout)
-	alarm(tmout);
-    zleactive = 1;
-    resetneeded = 1;
-    errflag = retflag = 0;
-    lastcol = -1;
-    initmodifier(&zmod);
-    prefixflag = 0;
     zrefresh();
+
     while (!done && !errflag) {
 
 	statusline = NULL;
@@ -786,6 +698,100 @@ zleread(char *lp, char *rp, int flags)
 	    if (!kungetct)
 		zrefresh();
     }
+}
+
+/* Read a line.  It is returned metafied. */
+
+/**/
+unsigned char *
+zleread(char *lp, char *rp, int flags)
+{
+    unsigned char *s;
+    int old_errno = errno;
+    int tmout = getiparam("TMOUT");
+
+#if defined(HAVE_POLL) || defined(HAVE_SELECT)
+    baud = getiparam("BAUD");
+    costmult = (baud) ? 3840000L / baud : 0;
+#endif
+
+    /* ZLE doesn't currently work recursively.  This is needed in case a *
+     * select loop is used in a function called from ZLE.  vared handles *
+     * this differently itself.                                          */
+    if(zleactive) {
+	char *pptbuf;
+	int pptlen;
+
+	pptbuf = unmetafy(promptexpand(lp, 0, NULL, NULL), &pptlen);
+	write(2, (WRITE_ARG_2_T)pptbuf, pptlen);
+	free(pptbuf);
+	return (unsigned char *)shingetline();
+    }
+
+    keytimeout = getiparam("KEYTIMEOUT");
+    if (!shout) {
+	if (SHTTY != -1)
+	    init_shout();
+
+	if (!shout)
+	    return NULL;
+	/* We could be smarter and default to a system read. */
+
+	/* If we just got a new shout, make sure the terminal is set up. */
+	if (termflags & TERM_UNKNOWN)
+	    init_term();
+    }
+
+    fflush(shout);
+    fflush(stderr);
+    intr();
+    insmode = unset(OVERSTRIKE);
+    eofsent = 0;
+    resetneeded = 0;
+    lpromptbuf = promptexpand(lp, 1, NULL, NULL);
+    pmpt_attr = txtchange;
+    rpromptbuf = promptexpand(rp, 1, NULL, NULL);
+    rpmpt_attr = txtchange;
+
+    zlereadflags = flags;
+    histline = curhist;
+    undoing = 1;
+    line = (unsigned char *)zalloc((linesz = 256) + 2);
+    virangeflag = lastcmd = done = cs = ll = mark = 0;
+    vichgflag = 0;
+    viinsbegin = 0;
+    statusline = NULL;
+    selectkeymap("main", 1);
+    selectlocalmap(NULL);
+    fixsuffix();
+    if ((s = (unsigned char *)getlinknode(bufstack))) {
+	setline((char *)s);
+	zsfree((char *)s);
+	if (stackcs != -1) {
+	    cs = stackcs;
+	    stackcs = -1;
+	    if (cs > ll)
+		cs = ll;
+	}
+	if (stackhist != -1) {
+	    histline = stackhist;
+	    stackhist = -1;
+	}
+    }
+    initundo();
+    if (isset(PROMPTCR))
+	putc('\r', shout);
+    if (tmout)
+	alarm(tmout);
+    zleactive = 1;
+    resetneeded = 1;
+    errflag = retflag = 0;
+    lastcol = -1;
+    initmodifier(&zmod);
+    prefixflag = 0;
+
+    zlecore();
+
     statusline = NULL;
     invalidatelist();
     trashzle();
@@ -1233,6 +1239,20 @@ whereis(char **args)
     return 0;
 }
 
+/**/
+int
+recursiveedit(char **args)
+{
+    int locerror;
+
+    zlecore();
+
+    locerror = errflag;
+    errflag = done = 0;
+
+    return locerror;
+}
+
 /**/
 mod_export void
 trashzle(void)