various tweaks.

src/libcomplete/complete.c

@@ -0,0 +1,139 @@
+#include <u.h>
+#include <libc.h>
+#include "complete.h"
+
+static int
+longestprefixlength(char *a, char *b, int n)
+{
+	int i, w;
+	Rune ra, rb;
+
+	for(i=0; i<n; i+=w){
+		w = chartorune(&ra, a);
+		chartorune(&rb, b);
+		if(ra != rb)
+			break;
+		a += w;
+		b += w;
+	}
+	return i;
+}
+
+void
+freecompletion(Completion *c)
+{
+	if(c){
+		free(c->filename);
+		free(c);
+	}
+}
+
+static int
+strpcmp(const void *va, const void *vb)
+{
+	char *a, *b;
+
+	a = *(char**)va;
+	b = *(char**)vb;
+	return strcmp(a, b);
+}
+
+Completion*
+complete(char *dir, char *s)
+{
+	long i, l, n, nmatch, len, nbytes;
+	int fd, minlen;
+	Dir *dirp;
+	char **name, *p;
+	ulong* mode;
+	Completion *c;
+
+	if(strchr(s, '/') != nil){
+		werrstr("slash character in name argument to complete()");
+		return nil;
+	}
+
+	fd = open(dir, OREAD);
+	if(fd < 0)
+		return nil;
+
+	n = dirreadall(fd, &dirp);
+	if(n <= 0)
+		return nil;
+
+	/* find longest string, for allocation */
+	len = 0;
+	for(i=0; i<n; i++){
+		l = strlen(dirp[i].name) + 1 + 1; /* +1 for /   +1 for \0 */
+		if(l > len)
+			len = l;
+	}
+
+	name = malloc(n*sizeof(char*));
+	mode = malloc(n*sizeof(ulong));
+	c = malloc(sizeof(Completion) + len);
+	if(name == nil || mode == nil || c == nil)
+		goto Return;
+	memset(c, 0, sizeof(Completion));
+
+	/* find the matches */
+	len = strlen(s);
+	nmatch = 0;
+	minlen = 1000000;
+	for(i=0; i<n; i++)
+		if(strncmp(s, dirp[i].name, len) == 0){
+			name[nmatch] = dirp[i].name;
+			mode[nmatch] = dirp[i].mode;
+			if(minlen > strlen(dirp[i].name))
+				minlen = strlen(dirp[i].name);
+			nmatch++;
+		}
+
+	if(nmatch > 0) {
+		/* report interesting results */
+		/* trim length back to longest common initial string */
+		for(i=1; i<nmatch; i++)
+			minlen = longestprefixlength(name[0], name[i], minlen);
+
+		/* build the answer */
+		c->complete = (nmatch == 1);
+		c->advance = c->complete || (minlen > len);
+		c->string = (char*)(c+1);
+		memmove(c->string, name[0]+len, minlen-len);
+		if(c->complete)
+			c->string[minlen++ - len] = (mode[0]&DMDIR)? '/' : ' ';
+		c->string[minlen - len] = '\0';
+	} else {
+		/* no match, so return all possible strings */
+		for(i=0; i<n; i++){
+			name[i] = dirp[i].name;
+			mode[i] = dirp[i].mode;
+		}
+		nmatch = n;
+	}
+
+	/* attach list of names */
+	nbytes = nmatch * sizeof(char*);
+	for(i=0; i<nmatch; i++)
+		nbytes += strlen(name[i]) + 1 + 1;
+	c->filename = malloc(nbytes);
+	if(c->filename == nil)
+		goto Return;
+	p = (char*)(c->filename + nmatch);
+	for(i=0; i<nmatch; i++){
+		c->filename[i] = p;
+		strcpy(p, name[i]);
+		p += strlen(p);
+		if(mode[i] & DMDIR)
+			*p++ = '/';
+		*p++ = '\0';
+	}
+	c->nfile = nmatch;
+	qsort(c->filename, c->nfile, sizeof(c->filename[0]), strpcmp);
+
+  Return:
+	free(name);
+	free(mode);
+	free(dirp);
+	return c;
+}

src/libcomplete/mkfile

@@ -0,0 +1,10 @@
+PLAN9=../..
+<$PLAN9/src/mkhdr
+
+LIB=libcomplete.a
+OFILES=\
+	complete.$O\
+
+HFILES=$PLAN9/include/complete.h
+
+<$PLAN9/src/mksyslib