Import sources from 2011-03-30 iso image

1 files changed, 203 insertions, 0 deletions

diff --git a/sys/src/cmd/vnc/chan.c b/sys/src/cmd/vnc/chan.c
new file mode 100755
index 000000000..14bcdf390
--- /dev/null
+++ b/sys/src/cmd/vnc/chan.c
@@ -0,0 +1,203 @@
+#include	<u.h>
+#include	<libc.h>
+#include	"compat.h"
+#include	"error.h"
+
+Chan*
+newchan(void)
+{
+	Chan *c;
+
+	c = smalloc(sizeof(Chan));
+
+	/* if you get an error before associating with a dev,
+	   close calls rootclose, a nop */
+	c->type = 0;
+	c->flag = 0;
+	c->ref = 1;
+	c->dev = 0;
+	c->offset = 0;
+	c->iounit = 0;
+	c->aux = 0;
+	c->name = 0;
+	return c;
+}
+
+void
+chanfree(Chan *c)
+{
+	c->flag = CFREE;
+
+	cnameclose(c->name);
+	free(c);
+}
+
+void
+cclose(Chan *c)
+{
+	if(c->flag&CFREE)
+		panic("cclose %#p", getcallerpc(&c));
+	if(decref(c))
+		return;
+
+	if(!waserror()){
+		devtab[c->type]->close(c);
+		poperror();
+	}
+
+	chanfree(c);
+}
+
+Chan*
+cclone(Chan *c)
+{
+	Chan *nc;
+	Walkqid *wq;
+
+	wq = devtab[c->type]->walk(c, nil, nil, 0);
+	if(wq == nil)
+		error("clone failed");
+	nc = wq->clone;
+	free(wq);
+	nc->name = c->name;
+	if(c->name)
+		incref(c->name);
+	return nc;
+}
+
+enum
+{
+	CNAMESLOP	= 20
+};
+
+static Ref ncname;
+
+void cleancname(Cname*);
+
+int
+isdotdot(char *p)
+{
+	return p[0]=='.' && p[1]=='.' && p[2]=='\0';
+}
+
+int
+incref(Ref *r)
+{
+	int x;
+
+	lock(r);
+	x = ++r->ref;
+	unlock(r);
+	return x;
+}
+
+int
+decref(Ref *r)
+{
+	int x;
+
+	lock(r);
+	x = --r->ref;
+	unlock(r);
+	if(x < 0)
+		panic("decref");
+
+	return x;
+}
+
+Cname*
+newcname(char *s)
+{
+	Cname *n;
+	int i;
+
+	n = smalloc(sizeof(Cname));
+	i = strlen(s);
+	n->len = i;
+	n->alen = i+CNAMESLOP;
+	n->s = smalloc(n->alen);
+	memmove(n->s, s, i+1);
+	n->ref = 1;
+	incref(&ncname);
+	return n;
+}
+
+void
+cnameclose(Cname *n)
+{
+	if(n == nil)
+		return;
+	if(decref(n))
+		return;
+	decref(&ncname);
+	free(n->s);
+	free(n);
+}
+
+Cname*
+addelem(Cname *n, char *s)
+{
+	int i, a;
+	char *t;
+	Cname *new;
+
+	if(s[0]=='.' && s[1]=='\0')
+		return n;
+
+	if(n->ref > 1){
+		/* copy on write */
+		new = newcname(n->s);
+		cnameclose(n);
+		n = new;
+	}
+
+	i = strlen(s);
+	if(n->len+1+i+1 > n->alen){
+		a = n->len+1+i+1 + CNAMESLOP;
+		t = smalloc(a);
+		memmove(t, n->s, n->len+1);
+		free(n->s);
+		n->s = t;
+		n->alen = a;
+	}
+	if(n->len>0 && n->s[n->len-1]!='/' && s[0]!='/')	/* don't insert extra slash if one is present */
+		n->s[n->len++] = '/';
+	memmove(n->s+n->len, s, i+1);
+	n->len += i;
+	if(isdotdot(s))
+		cleancname(n);
+	return n;
+}
+
+/*
+ * In place, rewrite name to compress multiple /, eliminate ., and process ..
+ */
+void
+cleancname(Cname *n)
+{
+	char *p;
+
+	if(n->s[0] == '#'){
+		p = strchr(n->s, '/');
+		if(p == nil)
+			return;
+		cleanname(p);
+
+		/*
+		 * The correct name is #i rather than #i/,
+		 * but the correct name of #/ is #/.
+		 */
+		if(strcmp(p, "/")==0 && n->s[1] != '/')
+			*p = '\0';
+	}else
+		cleanname(n->s);
+	n->len = strlen(n->s);
+}
+
+void
+isdir(Chan *c)
+{
+	if(c->qid.type & QTDIR)
+		return;
+	error(Enotdir);
+}