20060303a

1 files changed, 72 insertions, 0 deletions

diff --git a/liblogfs/open.c b/liblogfs/open.c
new file mode 100644
index 00000000..688e8822
--- /dev/null
+++ b/liblogfs/open.c
@@ -0,0 +1,72 @@
+#include "lib9.h"
+#include "logfs.h"
+#include "local.h"
+
+char *
+logfsserveropen(LogfsServer *server, u32int fid, uchar mode, Qid *qid)
+{
+	Fid *f;
+	Entry *e;
+	ulong modemask;
+
+	if(server->trace > 1)
+		print("logfsserveropen(%ud, %d)\n",  fid, mode);
+	f = logfsfidmapfindentry(server->fidmap, fid);
+	if(f == nil)
+		return logfsebadfid;
+	if(f->openmode >= 0)
+		return logfsefidopen;
+	e = f->entry;
+	SET(modemask);
+	switch(mode & 3) {
+	case OEXEC:
+		modemask = DMEXEC;
+		break;
+	case OREAD:
+		modemask = DMREAD;
+		break;
+	case OWRITE:
+		modemask = DMWRITE;
+		break;
+	case ORDWR:
+		modemask = DMWRITE | DMREAD;
+		break;
+	}
+	if(e->qid.type & QTDIR) {
+		if((modemask & DMWRITE) != 0 || (mode & (ORCLOSE | OTRUNC)) != 0)
+			return Eperm;
+	}
+	else {
+		if(mode & OTRUNC)
+			modemask |= DMWRITE;
+		if((mode & ORCLOSE) != 0 && !logfsuserpermcheck(server, e->parent, f, DMWRITE))
+			return Eperm;
+	}
+	if(!logfsuserpermcheck(server, e, f, modemask))
+		return Eperm;
+	if((e->qid.type & QTDIR) == 0 && (mode & OTRUNC) != 0 && (e->perm & DMAPPEND) == 0 && e->u.file.length != 0) {
+		LogMessage s;
+		char *errmsg;
+		s.type = LogfsLogTtrunc;
+		s.path = e->qid.path;
+		s.u.trunc.mtime = logfsnow();
+		s.u.trunc.cvers = e->u.file.cvers + 1;
+		s.u.trunc.muid = logfsisfindidfromname(server->is, f->uname);
+		errmsg = logfslog(server, 1, &s);
+		if(errmsg)
+			return errmsg;
+		e->muid = s.u.trunc.muid;
+		e->mtime = s.u.trunc.mtime;
+		e->qid.vers++;
+		e->u.file.cvers = s.u.trunc.cvers;
+		/*
+		 * zap all data and extents
+		 */
+		logfsextentlistwalk(e->u.file.extent, logfsunconditionallymarkfreeanddirty, server);
+		logfsextentlistreset(e->u.file.extent);
+		e->u.file.length = 0;
+	}
+	f->openmode = mode;
+	*qid = e->qid;
+	return nil;
+}