File system stuff.

1 files changed, 73 insertions, 0 deletions

diff --git a/src/libfs/walk.c b/src/libfs/walk.c
new file mode 100644
index 00000000..ad4eddc7
--- /dev/null
+++ b/src/libfs/walk.c
@@ -0,0 +1,73 @@
+/* Copyright (C) 2003 Russ Cox, Massachusetts Institute of Technology */
+/* See COPYRIGHT */
+
+#include <u.h>
+#include <libc.h>
+#include <fcall.h>
+#include <fs.h>
+#include "fsimpl.h"
+
+Fid*
+fswalk(Fid *fid, char *oname)
+{
+	char *freep, *name;
+	int i, nwalk;
+	char *p;
+	Fid *wfid;
+	Fcall tx, rx;
+
+	freep = nil;
+	name = oname;
+	if(name){
+		freep = malloc(strlen(name)+1);
+		if(freep == nil)
+			return nil;
+		strcpy(freep, name);
+		name = freep;
+	}
+
+	if((wfid = _fsgetfid(fid->fs)) == nil){
+		free(freep);
+		return nil;
+	}
+
+	nwalk = 0;
+	do{
+		/* collect names */
+		for(i=0; name && *name && i < MAXWELEM; ){
+			p = name;
+			name = strchr(name, '/');
+			if(name)
+				*name++ = 0;
+			if(*p == 0)
+				continue;
+			tx.wname[i++] = p;
+		}
+
+		/* do a walk */
+		tx.type = Twalk;
+		tx.fid = nwalk ? wfid->fid : fid->fid;
+		tx.newfid = wfid->fid;
+		tx.nwname = i;
+		if(fsrpc(fid->fs, &tx, &rx, 0) < 0){
+		Error:
+			free(freep);
+			if(nwalk)
+				fsclose(wfid);
+			else
+				_fsputfid(wfid);
+			return nil;
+		}
+		if(rx.nwqid != tx.nwname){
+			/* XXX lame error */
+			werrstr("file '%s' not found", oname);
+			goto Error;
+		}
+		if(rx.nwqid == 0)
+			wfid->qid = fid->qid;
+		else
+			wfid->qid = rx.wqid[rx.nwqid-1];
+		nwalk++;
+	}while(name && *name);
+	return wfid;
+}