File system stuff.
diff --git a/src/lib9/convM2D.c b/src/lib9/convM2D.c
new file mode 100644
index 0000000..6f4b4bd
--- /dev/null
+++ b/src/lib9/convM2D.c
@@ -0,0 +1,94 @@
+#include <u.h>
+#include <libc.h>
+#include <fcall.h>
+
+int
+statcheck(uchar *buf, uint nbuf)
+{
+ uchar *ebuf;
+ int i;
+
+ ebuf = buf + nbuf;
+
+ if(nbuf < STATFIXLEN || nbuf != BIT16SZ + GBIT16(buf))
+ return -1;
+
+ buf += STATFIXLEN - 4 * BIT16SZ;
+
+ for(i = 0; i < 4; i++){
+ if(buf + BIT16SZ > ebuf)
+ return -1;
+ buf += BIT16SZ + GBIT16(buf);
+ }
+
+ if(buf != ebuf)
+ return -1;
+
+ return 0;
+}
+
+static char nullstring[] = "";
+
+uint
+convM2D(uchar *buf, uint nbuf, Dir *d, char *strs)
+{
+ uchar *p, *ebuf;
+ char *sv[4];
+ int i, ns;
+
+ if(nbuf < STATFIXLEN)
+ return 0;
+
+ p = buf;
+ ebuf = buf + nbuf;
+
+ p += BIT16SZ; /* ignore size */
+ d->type = GBIT16(p);
+ p += BIT16SZ;
+ d->dev = GBIT32(p);
+ p += BIT32SZ;
+ d->qid.type = GBIT8(p);
+ p += BIT8SZ;
+ d->qid.vers = GBIT32(p);
+ p += BIT32SZ;
+ d->qid.path = GBIT64(p);
+ p += BIT64SZ;
+ d->mode = GBIT32(p);
+ p += BIT32SZ;
+ d->atime = GBIT32(p);
+ p += BIT32SZ;
+ d->mtime = GBIT32(p);
+ p += BIT32SZ;
+ d->length = GBIT64(p);
+ p += BIT64SZ;
+
+ for(i = 0; i < 4; i++){
+ if(p + BIT16SZ > ebuf)
+ return 0;
+ ns = GBIT16(p);
+ p += BIT16SZ;
+ if(p + ns > ebuf)
+ return 0;
+ if(strs){
+ sv[i] = strs;
+ memmove(strs, p, ns);
+ strs += ns;
+ *strs++ = '\0';
+ }
+ p += ns;
+ }
+
+ if(strs){
+ d->name = sv[0];
+ d->uid = sv[1];
+ d->gid = sv[2];
+ d->muid = sv[3];
+ }else{
+ d->name = nullstring;
+ d->uid = nullstring;
+ d->gid = nullstring;
+ d->muid = nullstring;
+ }
+
+ return p - buf;
+}
