1 files changed, 404 insertions, 0 deletions
diff --git a/src/cmd/venti/arenas.c b/src/cmd/venti/arenas.c
new file mode 100644
index 00000000..5275b938
--- /dev/null
+++ b/src/cmd/venti/arenas.c
@@ -0,0 +1,404 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+typedef struct AHash	AHash;
+
+/*
+ * hash table for finding arena's based on their names.
+ */
+struct AHash
+{
+	AHash	*next;
+	Arena	*arena;
+};
+
+enum
+{
+	AHashSize	= 512
+};
+
+static AHash	*ahash[AHashSize];
+
+static u32int
+hashstr(char *s)
+{
+	u32int h;
+	int c;
+
+	h = 0;
+	for(; c = *s; s++){
+		c ^= c << 6;
+		h += (c << 11) ^ (c >> 1);
+		c = *s;
+		h ^= (c << 14) + (c << 7) + (c << 4) + c;
+	}
+	return h;
+}
+
+int
+addarena(Arena *arena)
+{
+	AHash *a;
+	u32int h;
+
+	h = hashstr(arena->name) & (AHashSize - 1);
+	a = MK(AHash);
+	if(a == nil)
+		return -1;
+	a->arena = arena;
+	a->next = ahash[h];
+	ahash[h] = a;
+	return 0;
+}
+
+Arena*
+findarena(char *name)
+{
+	AHash *a;
+	u32int h;
+
+	h = hashstr(name) & (AHashSize - 1);
+	for(a = ahash[h]; a != nil; a = a->next)
+		if(strcmp(a->arena->name, name) == 0)
+			return a->arena;
+	return nil;
+}
+
+int
+delarena(Arena *arena)
+{
+	AHash *a, *last;
+	u32int h;
+
+	h = hashstr(arena->name) & (AHashSize - 1);
+	last = nil;
+	for(a = ahash[h]; a != nil; a = a->next){
+		if(a->arena == arena){
+			if(last != nil)
+				last->next = a->next;
+			else
+				ahash[h] = a->next;
+			free(a);
+			return 0;
+		}
+		last = a;
+	}
+	return -1;
+}
+
+ArenaPart*
+initarenapart(Part *part)
+{
+	AMapN amn;
+	ArenaPart *ap;
+	ZBlock *b;
+	u32int i;
+	int ok;
+
+	b = alloczblock(HeadSize, 0);
+	if(b == nil || readpart(part, PartBlank, b->data, HeadSize) < 0){
+		seterr(EAdmin, "can't read arena partition header: %r");
+		return nil;
+	}
+
+	ap = MKZ(ArenaPart);
+	if(ap == nil){
+		freezblock(b);
+		return nil;
+	}
+	ap->part = part;
+	ok = unpackarenapart(ap, b->data);
+	freezblock(b);
+	if(ok < 0){
+		seterr(ECorrupt, "corrupted arena partition header: %r");
+		freearenapart(ap, 0);
+		return nil;
+	}
+
+	ap->tabbase = (PartBlank + HeadSize + ap->blocksize - 1) & ~(ap->blocksize - 1);
+	if(ap->version != ArenaPartVersion){
+		seterr(ECorrupt, "unknown arena partition version %d", ap->version);
+		freearenapart(ap, 0);
+		return nil;
+	}
+	if(ap->blocksize & (ap->blocksize - 1)){
+		seterr(ECorrupt, "illegal non-power-of-2 block size %d\n", ap->blocksize);
+		freearenapart(ap, 0);
+		return nil;
+	}
+	if(ap->tabbase >= ap->arenabase){
+		seterr(ECorrupt, "arena partition table overlaps with arena storage");
+		freearenapart(ap, 0);
+		return nil;
+	}
+	ap->tabsize = ap->arenabase - ap->tabbase;
+	partblocksize(part, ap->blocksize);
+	ap->size = ap->part->size & ~(u64int)(ap->blocksize - 1);
+
+	if(readarenamap(&amn, part, ap->tabbase, ap->tabsize) < 0){
+		freearenapart(ap, 0);
+		return nil;
+	}
+	ap->narenas = amn.n;
+	ap->map = amn.map;
+	if(okamap(ap->map, ap->narenas, ap->arenabase, ap->size, "arena table") < 0){
+		freearenapart(ap, 0);
+		return nil;
+	}
+
+	ap->arenas = MKNZ(Arena*, ap->narenas);
+	for(i = 0; i < ap->narenas; i++){
+		ap->arenas[i] = initarena(part, ap->map[i].start, ap->map[i].stop - ap->map[i].start, ap->blocksize);
+		if(ap->arenas[i] == nil){
+			freearenapart(ap, 1);
+			return nil;
+		}
+		if(namecmp(ap->map[i].name, ap->arenas[i]->name) != 0){
+			seterr(ECorrupt, "arena name mismatches with expected name: %s vs. %s",
+				ap->map[i].name, ap->arenas[i]->name);
+			freearenapart(ap, 1);
+			return nil;
+		}
+		if(findarena(ap->arenas[i]->name)){
+			seterr(ECorrupt, "duplicate arena name %s in %s",
+				ap->map[i].name, ap->part->name);
+			freearenapart(ap, 1);
+			return nil;
+		}
+	}
+
+	for(i = 0; i < ap->narenas; i++)
+		addarena(ap->arenas[i]);
+
+	return ap;
+}
+
+ArenaPart*
+newarenapart(Part *part, u32int blocksize, u32int tabsize)
+{
+	ArenaPart *ap;
+
+	if(blocksize & (blocksize - 1)){
+		seterr(ECorrupt, "illegal non-power-of-2 block size %d\n", blocksize);
+		return nil;
+	}
+	ap = MKZ(ArenaPart);
+	if(ap == nil)
+		return nil;
+
+	ap->version = ArenaPartVersion;
+	ap->part = part;
+	ap->blocksize = blocksize;
+	partblocksize(part, blocksize);
+	ap->size = part->size & ~(u64int)(blocksize - 1);
+	ap->tabbase = (PartBlank + HeadSize + blocksize - 1) & ~(blocksize - 1);
+	ap->arenabase = (ap->tabbase + tabsize + blocksize - 1) & ~(blocksize - 1);
+	ap->tabsize = ap->arenabase - ap->tabbase;
+	ap->narenas = 0;
+
+	if(wbarenapart(ap) < 0){
+		freearenapart(ap, 0);
+		return nil;
+	}
+
+	return ap;
+}
+
+int
+wbarenapart(ArenaPart *ap)
+{
+	ZBlock *b;
+
+	if(okamap(ap->map, ap->narenas, ap->arenabase, ap->size, "arena table") < 0)
+		return -1;
+	b = alloczblock(HeadSize, 1);
+	if(b == nil)
+//ZZZ set error message?
+		return -1;
+
+	if(packarenapart(ap, b->data) < 0){
+		seterr(ECorrupt, "can't make arena partition header: %r");
+		freezblock(b);
+		return -1;
+	}
+	if(writepart(ap->part, PartBlank, b->data, HeadSize) < 0){
+		seterr(EAdmin, "can't write arena partition header: %r");
+		freezblock(b);
+		return -1;
+	}
+	freezblock(b);
+
+	return wbarenamap(ap->map, ap->narenas, ap->part, ap->tabbase, ap->tabsize);
+}
+
+void
+freearenapart(ArenaPart *ap, int freearenas)
+{
+	int i;
+
+	if(ap == nil)
+		return;
+	if(freearenas){
+		for(i = 0; i < ap->narenas; i++){
+			if(ap->arenas[i] == nil)
+				continue;
+			delarena(ap->arenas[i]);
+			freearena(ap->arenas[i]);
+		}
+	}
+	free(ap->map);
+	free(ap->arenas);
+	free(ap);
+}
+
+int
+okamap(AMap *am, int n, u64int start, u64int stop, char *what)
+{
+	u64int last;
+	u32int i;
+
+	last = start;
+	for(i = 0; i < n; i++){
+		if(am[i].start < last){
+			if(i == 0)
+				seterr(ECorrupt, "invalid start address in %s", what);
+			else
+				seterr(ECorrupt, "overlapping ranges in %s", what);
+			return -1;
+		}
+		if(am[i].stop < am[i].start){
+			seterr(ECorrupt, "invalid range in %s", what);
+			return -1;
+		}
+		last = am[i].stop;
+	}
+	if(last > stop){
+		seterr(ECorrupt, "invalid ending address in %s", what);
+		return -1;
+	}
+	return 0;
+}
+
+int
+maparenas(AMap *am, Arena **arenas, int n, char *what)
+{
+	u32int i;
+
+	for(i = 0; i < n; i++){
+		arenas[i] = findarena(am[i].name);
+		if(arenas[i] == nil){
+			seterr(EAdmin, "can't find arena '%s' for '%s'\n", am[i].name, what);
+			return -1;
+		}
+	}
+	return 0;
+}
+
+int
+readarenamap(AMapN *amn, Part *part, u64int base, u32int size)
+{
+	IFile f;
+	u32int ok;
+
+	if(partifile(&f, part, base, size) < 0)
+		return -1;
+	ok = parseamap(&f, amn);
+	freeifile(&f);
+	return ok;
+}
+
+int
+wbarenamap(AMap *am, int n, Part *part, u64int base, u64int size)
+{
+	Fmt f;
+	ZBlock *b;
+
+	b = alloczblock(size, 1);
+	if(b == nil)
+		return -1;
+
+	fmtzbinit(&f, b);
+
+	if(outputamap(&f, am, n) < 0){
+		seterr(ECorrupt, "arena set size too small");
+		freezblock(b);
+		return -1;
+	}
+	if(writepart(part, base, b->data, size) < 0){
+		seterr(EAdmin, "can't write arena set: %r");
+		freezblock(b);
+		return -1;
+	}
+	freezblock(b);
+	return 0;
+}
+
+/*
+ * amap: n '\n' amapelem * n
+ * n: u32int
+ * amapelem: name '\t' astart '\t' asize '\n'
+ * astart, asize: u64int
+ */
+int
+parseamap(IFile *f, AMapN *amn)
+{
+	AMap *am;
+	u64int v64;
+	u32int v;
+	char *s, *flds[4];
+	int i, n;
+
+	/*
+	 * arenas
+	 */
+	if(ifileu32int(f, &v) < 0){
+		seterr(ECorrupt, "syntax error: bad number of elements in %s", f->name);
+		return -1;
+	}
+	n = v;
+	if(n > MaxAMap){
+		seterr(ECorrupt, "illegal number of elements in %s", f->name);
+		return -1;
+	}
+	am = MKNZ(AMap, n);
+	if(am == nil)
+		return -1;
+	for(i = 0; i < n; i++){
+		s = ifileline(f);
+		if(s == nil || getfields(s, flds, 4, 0, "\t") != 3)
+			return -1;
+		if(nameok(flds[0]) < 0)
+			return -1;
+		namecp(am[i].name, flds[0]);
+		if(stru64int(flds[1], &v64) < 0){
+			seterr(ECorrupt, "syntax error: bad arena base address in %s", f->name);
+			free(am);
+			return -1;
+		}
+		am[i].start = v64;
+		if(stru64int(flds[2], &v64) < 0){
+			seterr(ECorrupt, "syntax error: bad arena size in %s", f->name);
+			free(am);
+			return -1;
+		}
+		am[i].stop = v64;
+	}
+
+	amn->map = am;
+	amn->n = n;
+	return 0;
+}
+
+int
+outputamap(Fmt *f, AMap *am, int n)
+{
+	int i;
+
+	if(fmtprint(f, "%ud\n", n) < 0)
+		return -1;
+	for(i = 0; i < n; i++)
+		if(fmtprint(f, "%s\t%llud\t%llud\n", am[i].name, am[i].start, am[i].stop) < 0)
+			return -1;
+	return 0;
+}