fossil: import from plan 9

R=rsc
https://codereview.appspot.com/7988047

1 files changed, 132 insertions, 0 deletions

diff --git a/src/cmd/fossil/9dir.c b/src/cmd/fossil/9dir.c
new file mode 100644
index 00000000..09b483bd
--- /dev/null
+++ b/src/cmd/fossil/9dir.c
@@ -0,0 +1,132 @@
+#include "stdinc.h"
+
+#include "9.h"
+
+/* one entry buffer for reading directories */
+struct DirBuf {
+	DirEntryEnum*	dee;
+	int		valid;
+	DirEntry	de;
+};
+
+static DirBuf*
+dirBufAlloc(File* file)
+{
+	DirBuf *db;
+
+	db = vtMemAllocZ(sizeof(DirBuf));
+	db->dee = deeOpen(file);
+	if(db->dee == nil){
+		/* can happen if dir is removed from under us */
+		vtMemFree(db);
+		return nil;
+	}
+	return db;
+}
+
+void
+dirBufFree(DirBuf* db)
+{
+	if(db == nil)
+		return;
+
+	if(db->valid)
+		deCleanup(&db->de);
+	deeClose(db->dee);
+	vtMemFree(db);
+}
+
+int
+dirDe2M(DirEntry* de, uchar* p, int np)
+{
+	int n;
+	Dir dir;
+
+	memset(&dir, 0, sizeof(Dir));
+
+	dir.qid.path = de->qid;
+	dir.qid.vers = de->mcount;
+	dir.mode = de->mode & 0777;
+	if(de->mode & ModeAppend){
+		dir.qid.type |= QTAPPEND;
+		dir.mode |= DMAPPEND;
+	}
+	if(de->mode & ModeExclusive){
+		dir.qid.type |= QTEXCL;
+		dir.mode |= DMEXCL;
+	}
+	if(de->mode & ModeDir){
+		dir.qid.type |= QTDIR;
+		dir.mode |= DMDIR;
+	}
+	if(de->mode & ModeSnapshot){
+		dir.qid.type |= QTMOUNT;	/* just for debugging */
+		dir.mode |= DMMOUNT;
+	}
+	if(de->mode & ModeTemporary){
+		dir.qid.type |= QTTMP;
+		dir.mode |= DMTMP;
+	}
+
+	dir.atime = de->atime;
+	dir.mtime = de->mtime;
+	dir.length = de->size;
+
+	dir.name = de->elem;
+	if((dir.uid = unameByUid(de->uid)) == nil)
+		dir.uid = smprint("(%s)", de->uid);
+	if((dir.gid = unameByUid(de->gid)) == nil)
+		dir.gid = smprint("(%s)", de->gid);
+	if((dir.muid = unameByUid(de->mid)) == nil)
+		dir.muid = smprint("(%s)", de->mid);
+
+	n = convD2M(&dir, p, np);
+
+	vtMemFree(dir.muid);
+	vtMemFree(dir.gid);
+	vtMemFree(dir.uid);
+
+	return n;
+}
+
+int
+dirRead(Fid* fid, uchar* p, int count, vlong offset)
+{
+	int n, nb;
+	DirBuf *db;
+
+	/*
+	 * special case of rewinding a directory
+	 * otherwise ignore the offset
+	 */
+	if(offset == 0 && fid->db){
+		dirBufFree(fid->db);
+		fid->db = nil;
+	}
+
+	if(fid->db == nil){
+		fid->db = dirBufAlloc(fid->file);
+		if(fid->db == nil)
+			return -1;
+	}
+
+	db = fid->db;
+
+	for(nb = 0; nb < count; nb += n){
+		if(!db->valid){
+			n = deeRead(db->dee, &db->de);
+			if(n < 0)
+				return -1;
+			if(n == 0)
+				break;
+			db->valid = 1;
+		}
+		n = dirDe2M(&db->de, p+nb, count-nb);
+		if(n <= BIT16SZ)
+			break;
+		db->valid = 0;
+		deCleanup(&db->de);
+	}
+
+	return nb;
+}