Re: Exclude non-executables from command completion

[Peter Stephenson <pws@xxxxxxx>]

On Thu, 17 Sep 2009 18:08:26 +0200
Eike von Seggern <eikevons@xxxxxxxx> wrote:
> Is it possible, that command completion only completes on commands that
> are actually executable? As it happens I have to work on machines that
> have non-executables in directories in $PATH.

I'm not sure why we don't check that commands are executables, was there
ever a reason?

P.S. we are woefully dependent on PATH_MAX.  That's one of those things it
would be really good to fix that's not going to change without a ten-fold
increase in people working on the shell.

Index: Src/hashtable.c
===================================================================
RCS file: /cvsroot/zsh/zsh/Src/hashtable.c,v
retrieving revision 1.31
diff -u -r1.31 hashtable.c
--- Src/hashtable.c	11 Feb 2009 20:42:16 -0000	1.31
+++ Src/hashtable.c	18 Sep 2009 10:22:05 -0000
@@ -630,20 +630,50 @@
 {
     Cmdnam cn;
     DIR *dir;
-    char *fn;
+    char *fn, *unmetadir, *pathbuf, *pathptr;
+    int dirlen;
 #if defined(_WIN32) || defined(__CYGWIN__)
     char *exe;
 #endif /* _WIN32 || _CYGWIN__ */
 
-    if (isrelative(*dirp) || !(dir = opendir(unmeta(*dirp))))
+    if (isrelative(*dirp))
 	return;
+    unmetadir = unmeta(*dirp);
+    if (!(dir = opendir(unmetadir)))
+	return;
+
+    dirlen = strlen(unmetadir);
+    pathbuf = (char *)zalloc(dirlen + PATH_MAX + 2);
+    sprintf(pathbuf, "%s/", unmetadir);
+    pathptr = pathbuf + dirlen + 1;
 
     while ((fn = zreaddir(dir, 1))) {
 	if (!cmdnamtab->getnode(cmdnamtab, fn)) {
-	    cn = (Cmdnam) zshcalloc(sizeof *cn);
-	    cn->node.flags = 0;
-	    cn->u.name = dirp;
-	    cmdnamtab->addnode(cmdnamtab, ztrdup(fn), cn);
+	    char *fname = ztrdup(fn);
+	    struct stat statbuf;
+	    int add = 0, dummylen;
+
+	    unmetafy(fn, &dummylen);
+	    if (strlen(fn) > PATH_MAX) {
+		/* Too heavy to do all the allocation */
+		add = 1;
+	    } else {
+		strcpy(pathptr, fn);
+		/*
+		 * This is the same test as for the glob qualifier for
+		 * executable plain files.
+		 */
+		if (stat(pathbuf, &statbuf) == 0 &&
+		    S_ISREG(statbuf.st_mode) && (statbuf.st_mode & S_IXUGO))
+		    add = 1;
+	    }
+	    if (add) {
+		cn = (Cmdnam) zshcalloc(sizeof *cn);
+		cn->node.flags = 0;
+		cn->u.name = dirp;
+		cmdnamtab->addnode(cmdnamtab, fname, cn);
+	    } else
+		zsfree(fname);
 	}
 #if defined(_WIN32) || defined(__CYGWIN__)
 	/* Hash foo.exe as foo, since when no real foo exists, foo.exe
@@ -664,6 +694,7 @@
 #endif /* _WIN32 || __CYGWIN__ */
     }
     closedir(dir);
+    zfree(pathbuf, dirlen + PATH_MAX + 2);
 }
 
 /* Go through user's PATH and add everything to *


-- 
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