1 files changed, 174 insertions, 0 deletions
diff --git a/src/cmd/venti/srv/syncarena.c b/src/cmd/venti/srv/syncarena.c
new file mode 100644
index 00000000..d11ca4f3
--- /dev/null
+++ b/src/cmd/venti/srv/syncarena.c
@@ -0,0 +1,174 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+static int	writeclumphead(Arena *arena, u64int aa, Clump *cl);
+static int	writeclumpmagic(Arena *arena, u64int aa, u32int magic);
+
+int
+clumpinfocmp(ClumpInfo *c, ClumpInfo *d)
+{
+	return c->type != d->type
+		|| c->size != d->size
+		|| c->uncsize != d->uncsize
+		|| scorecmp(c->score, d->score)!=0;
+}
+
+/*
+ * synchronize the clump info directory with
+ * with the clumps actually stored in the arena.
+ * the directory should be at least as up to date
+ * as the arena's trailer.
+ *
+ * checks/updates at most n clumps.
+ *
+ * returns 0 if ok, flags if error occurred
+ */
+int
+syncarena(Arena *arena, u64int start, u32int n, int zok, int fix)
+{
+	ZBlock *lump;
+	Clump cl;
+	ClumpInfo ci;
+	static ClumpInfo zci = { .type = -1 };
+	u8int score[VtScoreSize];
+	u64int uncsize, used, aa;
+	u32int clump, clumps, cclumps, magic;
+	int err, flush, broken;
+	AState as;
+
+	used = arena->memstats.used;
+	clumps = arena->memstats.clumps;
+	cclumps = arena->memstats.cclumps;
+	uncsize = arena->memstats.uncsize;
+	trace(TraceProc, "syncarena start");
+	flush = 0;
+	err = 0;
+	for(; n; n--){
+		aa = arena->memstats.used;
+		clump = arena->memstats.clumps;
+		magic = clumpmagic(arena, aa);
+		if(magic == ClumpFreeMagic)
+			break;
+		if(magic != arena->clumpmagic){
+			fprint(2, "%s: illegal clump magic number=%#8.8ux at clump=%d\n", arena->name, magic, clump);
+			/* err |= SyncDataErr; */
+			if(fix && writeclumpmagic(arena, aa, ClumpFreeMagic) < 0){
+				fprint(2, "can't write corrected clump free magic: %r");
+				err |= SyncFixErr;
+			}
+			break;
+		}
+
+		broken = 0;
+		lump = loadclump(arena, aa, 0, &cl, score, 0);
+		if(lump == nil){
+			fprint(2, "%s: clump=%d failed to read correctly: %r\n", arena->name, clump);
+			break;
+			err |= SyncDataErr;
+		}else if(cl.info.type != VtCorruptType){
+			scoremem(score, lump->data, cl.info.uncsize);
+			if(scorecmp(cl.info.score, score) != 0){
+				/* ignore partially written block */
+				if(cl.encoding == ClumpENone)
+					break;
+				fprint(2, "%s: clump=%d has mismatched score\n", arena->name, clump);
+				err |= SyncDataErr;
+				broken = 1;
+			}else if(vttypevalid(cl.info.type) < 0){
+				fprint(2, "%s: clump=%d has invalid type %d", arena->name, clump, cl.info.type);
+				err |= SyncDataErr;
+				broken = 1;
+			}
+			if(broken && fix){
+				cl.info.type = VtCorruptType;
+				if(writeclumphead(arena, aa, &cl) < 0){
+					fprint(2, "%s: can't write corrected clump header: %r", arena->name);
+					err |= SyncFixErr;
+				}
+			}
+		}
+		freezblock(lump);
+		arena->memstats.used += ClumpSize + cl.info.size;
+
+		arena->memstats.clumps++;
+		if(!broken && readclumpinfo(arena, clump, &ci)<0){
+			fprint(2, "%s: arena directory read failed\n", arena->name);
+			broken = 1;
+		}else if(!broken && clumpinfocmp(&ci, &cl.info)!=0){
+			if(clumpinfocmp(&ci, &zci) == 0){
+				err |= SyncCIZero;
+				if(!zok)
+					fprint(2, "%s: unwritten clump info for clump=%d\n", arena->name, clump);
+			}else{
+				err |= SyncCIErr;
+				fprint(2, "%s: bad clump info for clump=%d\n", arena->name, clump);
+				fprint(2, "\texpected score=%V type=%d size=%d uncsize=%d\n",
+					cl.info.score, cl.info.type, cl.info.size, cl.info.uncsize);
+				fprint(2, "\tfound score=%V type=%d size=%d uncsize=%d\n",
+					ci.score, ci.type, ci.size, ci.uncsize);
+			}
+			broken = 1;
+		}
+		if(broken && fix){
+			flush = 1;
+			ci = cl.info;
+			if(writeclumpinfo(arena, clump, &ci) < 0){
+				fprint(2, "%s: can't write correct clump directory: %r\n", arena->name);
+				err |= SyncFixErr;
+			}
+		}
+		trace(TraceProc, "syncarena unindexed clump %V %d", cl.info.score, arena->memstats.clumps);
+
+		arena->memstats.uncsize += cl.info.uncsize;
+		if(cl.info.size < cl.info.uncsize)
+			arena->memstats.cclumps++;
+	}
+
+	if(flush){
+		trace(TraceProc, "syncarena flush");
+		arena->wtime = now();
+		if(arena->ctime == 0 && arena->memstats.clumps)
+			arena->ctime = arena->wtime;
+		flushdcache();
+	}
+
+	if(used != arena->memstats.used
+	|| clumps != arena->memstats.clumps
+	|| cclumps != arena->memstats.cclumps
+	|| uncsize != arena->memstats.uncsize)
+		err |= SyncHeader;
+	if(start && (err&SyncHeader)){
+		trace(TraceProc, "syncarena setdcachestate");
+		as.arena = arena;
+		as.aa = start+arena->memstats.used;
+		as.stats = arena->memstats;
+		setdcachestate(&as);
+	}
+
+	return err;
+}
+
+static int
+writeclumphead(Arena *arena, u64int aa, Clump *cl)
+{
+	ZBlock *zb;
+	int bad;
+
+	zb = alloczblock(ClumpSize, 0, arena->blocksize);
+	if(zb == nil)
+		return -1;
+	bad = packclump(cl, zb->data, arena->clumpmagic)<0
+		|| writearena(arena, aa, zb->data, ClumpSize) != ClumpSize;
+	freezblock(zb);
+	return bad ? -1 : 0;
+}
+
+static int
+writeclumpmagic(Arena *arena, u64int aa, u32int magic)
+{
+	u8int buf[U32Size];
+
+	packmagic(magic, buf);
+	return writearena(arena, aa, buf, U32Size) == U32Size;
+}