Re: completion through windows drive letters

[Peter Stephenson <pws@xxxxxxx>]

On Sun, 2 Aug 2009 16:20:03 -0400
Anthony Heading <ajrh@xxxxxxxx> wrote:
> Using zsh on cygwin with old-style completion, "cd c:/P<TAB>" will
> complete e.g. to c:/Program Files et al.  Using the compinit system,
> this no longer works for me.

This seemed to work.  I've intercepted the function within compfiles -p/P
that tests for exact matches, which is usually set by the style
accept-exact (that's different from accept-exact-dirs which is handled
entirely in the function and simply shortcuts later tests), and forced it
to handle files ending in a colon as if accept-exact was on---it still
tests for them but won't attempt to use patterns with them.

I've also added some comments based on what seems to be happening.

Index: Src/Zle/computil.c
===================================================================
RCS file: /cvsroot/zsh/zsh/Src/Zle/computil.c,v
retrieving revision 1.114
diff -u -r1.114 computil.c
--- Src/Zle/computil.c	15 Nov 2008 21:27:46 -0000	1.114
+++ Src/Zle/computil.c	5 Aug 2009 09:23:49 -0000
@@ -3931,6 +3931,22 @@
 
 #define PATH_MAX2 (PATH_MAX * 2)
 
+/*
+ * Return a list of files we should accept exactly, without
+ * trying pattern matching.
+ *
+ * This is based on the accept-exact style, which may be
+ * an array so is passed in via "accept".  The trial files
+ * are input in "names".  "skipped" is passed down straight
+ * from the file completion function:  it's got something to
+ * do with other components in the path but it's hard to work out
+ * quite what.
+ *
+ * There is one extra trick here for Cygwin.  Regardless of the style,
+ * if the file ends in a colon it has to be a drive or a special device
+ * file and we always accept it exactly because treating it as a pattern
+ * won't work.
+ */
 static LinkList
 cfp_test_exact(LinkList names, char **accept, char *skipped)
 {
@@ -3939,16 +3955,41 @@
     struct stat st;
     LinkNode node;
     LinkList ret = newlinklist(), alist = NULL;
+#ifdef __CYGWIN__
+    int accept_off = 0;
+#endif
 
-    if ((!(compprefix && *compprefix) && !(compsuffix && *compsuffix)) ||
-	(!accept || !*accept ||
-	 ((!strcmp(*accept, "false") || !strcmp(*accept, "no") ||
-	   !strcmp(*accept, "off") || !strcmp(*accept, "0")) && !accept[1])))
+    /*
+     * Don't do this unless completion has provided either a
+     * prefix or suffix from the command line.
+     */
+    if (!(compprefix && *compprefix) && !(compsuffix && *compsuffix))
 	return NULL;
 
-    if (accept[1] ||
-	(strcmp(*accept, "true") && strcmp(*accept, "yes") &&
-	 strcmp(*accept, "on") && strcmp(*accept, "1"))) {
+    /*
+     * See if accept-exact is off, implicitly or explicitly.
+     */
+    if (!accept || !*accept ||
+	((!strcmp(*accept, "false") || !strcmp(*accept, "no") ||
+	  !strcmp(*accept, "off") || !strcmp(*accept, "0")) && !accept[1])) {
+#ifdef __CYGWIN__
+	accept_off = 1;
+#else
+	/* If not Cygwin, nothing to do here. */
+	return NULL;
+#endif
+    }
+
+    /*
+     * See if the style is something other than just a boolean.
+     */
+    if (
+#ifdef __CYGWIN__
+	!accept_off &&
+#endif
+	(accept[1] ||
+	 (strcmp(*accept, "true") && strcmp(*accept, "yes") &&
+	  strcmp(*accept, "on") && strcmp(*accept, "1")))) {
 	Patprog prog;
 
 	alist = newlinklist();
@@ -3963,6 +4004,10 @@
 		addlinknode(alist, prog);
 	}
     }
+    /*
+     * Assemble the bits other than the set of file names:
+     * the other components, and the prefix and suffix.
+     */
     sl = strlen(skipped) + (compprefix ? strlen(compprefix) : 0) +
 	(compsuffix ? strlen(compsuffix) : 0);
 
@@ -3976,8 +4021,21 @@
 	if (l + sl < PATH_MAX2) {
 	    strcpy(buf, p);
 	    strcpy(buf + l, suf);
-
+#ifdef __CYGWIN__
+	    /*
+	     * If accept-exact is not set, accept this only if
+	     * it looks like a special file such as a drive.
+	     * We still test if it exists.
+	     */
+	    if (accept_off &&
+		(strchr(buf, '/') || buf[strlen(buf)-1] != ':'))
+		continue;
+#endif
 	    if (!ztat(buf, &st, 0)) {
+		/*
+		 * File exists; if accept-exact contained non-boolean
+		 * values it must match those, too.
+		 */
 		if (alist) {
 		    LinkNode anode;
 



-- 
Peter Stephenson <pws@xxxxxxx>            Software Engineer
Tel: +44 (0)1223 692070                   Cambridge Silicon Radio Limited
Churchill House, Cambridge Business Park, Cowley Road, Cambridge, CB4 0WZ, UK


'member of the CSR plc group of companies. CSR plc registered in England and Wales, registered number 4187346, registered office Churchill House, Cambridge Business Park, Cowley Road, Cambridge, CB4 0WZ, United Kingdom'