Vac works.

src/cmd/vac/dat.h

@@ -1,60 +1,27 @@
-typedef struct Source Source;
-typedef struct VacFile VacFile;
 typedef struct MetaBlock MetaBlock;
 typedef struct MetaEntry MetaEntry;
-typedef struct Lump Lump;
-typedef struct Cache Cache;
-typedef struct Super Super;
 
-enum {
-	NilBlock	= (~0UL),
+enum
+{
 	MaxBlock	= (1UL<<31),
 };
 
-
-struct VacFS {
-	int ref;
-	
-	/* need a read write lock? */
-
-	uchar score[VtScoreSize];
-	VacFile *root;
-	
-	VtSession *z;
-	int readOnly;
-	int bsize;		/* maximum block size */
-	uvlong qid;		/* next qid */
-	Cache *cache;
+enum {
+	BytesPerEntry = 100,	/* estimate of bytes per dir entries - determines number of index entries in the block */
+	FullPercentage = 80,	/* don't allocate in block if more than this percentage full */
+	FlushSize = 200,	/* number of blocks to flush */
+	DirtyPercentage = 50,	/* maximum percentage of dirty blocks */
 };
 
 
-struct Source {
-	VtLock *lk;
-
-	Cache *cache;	/* immutable */
-	int readOnly;	/* immutable */
-
-	Lump *lump;	/* lump containing venti dir entry */
-	ulong block;	/* block number within parent: immutable */
-	int entry;	/* which entry in the block: immutable */
-
-	/* most of a VtEntry, except the score */
-	ulong gen;	/* generation: immutable */
-	int dir;	/* dir flags: immutable */
-	int depth;	/* number of levels of pointer blocks */
-	int psize;	/* pointer block size: immutable */
-	int dsize;	/* data block size: immutable */
-	uvlong size;	/* size in bytes of file */
-
-	int epb;	/* dir entries per block = dize/VtEntrySize: immutable */
-};
-
-struct MetaEntry {
+struct MetaEntry
+{
 	uchar *p;
 	ushort size;
 };
 
-struct MetaBlock {
+struct MetaBlock
+{
 	int maxsize;		/* size of block */
 	int size;		/* size used */
 	int free;		/* free space within used size */
@@ -64,93 +31,13 @@ struct MetaBlock {
 	uchar *buf;
 };
 
-/*
- * contains a one block buffer
- * to avoid problems of the block changing underfoot
- * and to enable an interface that supports unget.
- */
-struct VacDirEnum {
+struct VacDirEnum
+{
 	VacFile *file;
-	
-	ulong block;	/* current block */
-	MetaBlock mb;	/* parsed version of block */
-	int index;	/* index in block */
-};
-
-/* Lump states */
-enum {
-	LumpFree,
-	LumpVenti,	/* on venti server: score > 2^32: just a cached copy */
-	LumpActive,	/* active */
-	LumpActiveRO,	/* active: read only block */
-	LumpActiveA,	/* active: achrived */
-	LumpSnap,	/* snapshot: */
-	LumpSnapRO,	/* snapshot: read only */
-	LumpSnapA,	/* snapshot: achived */
-	LumpZombie,	/* block with no pointer to it: waiting to be freed */
-	
-	LumpMax
-};
-
-/*
- * Each lump has a state and generation
- * The following invariants are maintained
- * 	Each lump has no more than than one parent per generation
- * 	For Active*, no child has a parent of a greater generation
- *	For Snap*, there is a snap parent of given generation and there are
- *		no parents of greater gen - implies no children of a greater gen
- *	For *RO, the lump is fixed - no change ca be made - all pointers
- *		are valid venti addresses
- *	For *A, the lump is on the venti server
- *	There are no pointers to Zombie lumps
- *
- * Transitions
- *	Archiver at generation g
- *	Mutator at generation h
- *	
- *	Want to modify a lump
- *		Venti: create new Active(h)
- *		Active(x): x == h: do nothing
- *		Acitve(x): x < h: change to Snap(h-1) + add Active(h)
- *		ActiveRO(x): change to SnapRO(h-1) + add Active(h)
- *		ActiveA(x): add Active(h)
- *		Snap*(x): should not occur
- *		Zombie(x): should not occur
- *	Want to archive
- *		Active(x): x != g: should never happen
- *		Active(x): x == g fix children and free them: move to ActoveRO(g);
- *		ActiveRO(x): x != g: should never happen
- *		ActiveRO(x): x == g: wait until it hits ActiveA or SnapA
- *		ActiveA(x): done
- *		Active(x): x < g: should never happen
- *		Snap(x): x >= g: fix children, freeing all SnapA(y) x == y;
- *		SnapRO(x): wait until it hits SnapA
- *
- */
-
-
-struct Lump {
-	int ref;
-
-	Cache *c;
-
-	VtLock *lk;
-	
-	int state;
-	ulong gen;
-
-	uchar 	*data;
-	uchar	score[VtScoreSize];	/* score of packet */
-	uchar	vscore[VtScoreSize];	/* venti score - when archived */
-	u8int	type;			/* type of packet */
-	int	dir;			/* part of a directory - extension of type */
-	u16int	asize;			/* allocated size of block */
-	Lump	*next;			/* doubly linked hash chains */
-	Lump	*prev;
-	u32int	heap;			/* index in heap table */
-	u32int	used;			/* last reference times */
-	u32int	used2;
-
-	u32int	addr;			/* mutable block address */
+	u32int boff;
+	int i, n;
+	VacDir *buf;
 };
 
+void _mbinit(MetaBlock*, u8int*, uint, uint);
+int _mbsearch(MetaBlock*, char*, int*, MetaEntry*);