improve acidleak performance and reduce memory usage
by doubling block and data allocations when necessary,
instead of allocating 64 at a time.  this decreases memory
used ~50% and runtime by about 90% when using leak(1)
on programs that allocation many small blocks, such as
older versions of upas/fs.

Reference: /n/sources/patch/applied/acidleak
Date: Sat Aug  8 21:33:02 CES 2009
Signed-off-by: quanstro@quanstro.net

--- /sys/src/cmd/aux/acidleak.c	Sat Aug  8 21:28:38 2009
+++ /sys/src/cmd/aux/acidleak.c	Sat Aug  8 21:28:36 2009
@@ -56,11 +56,13 @@
 };
 
 Block *block;
-int nblock;
+uint nblock;
+uint ablock;
 
 Data *data;
 Data *edata;
-int ndata;
+uint ndata;
+uint adata;
 
 int
 addrcmp(void *va, void *vb)
@@ -200,8 +202,11 @@
 		p[Blinelen(&bio)-1] = '\0';
 		nf = tokenize(p, f, nelem(f));
 		if(nf >= 4 && strcmp(f[0], "data") == 0) {
-			if(ndata%64==0)
-				data = erealloc(data, (ndata+64)*sizeof(Data));
+			if(ndata == adata){
+				if(adata == 0)
+					adata = 4096;
+				data = erealloc(data, (adata <<= 1)*sizeof(Data));
+			}
 			data[ndata].addr = strtoul(f[1], nil, 0);
 			data[ndata].val = strtoul(f[2], nil, 0);
 			data[ndata].type = f[3][0];
@@ -209,8 +214,11 @@
 			ndata++;
 		}
 		if(nf >= 5 && (strcmp(f[0], "block") == 0 || strcmp(f[0], "free") == 0)) {
-			if(nblock%64 == 0)
-				block = erealloc(block, (nblock+64)*sizeof(Block));
+			if(nblock == ablock){
+				if(ablock == 0)
+					ablock = 4096;
+				block = erealloc(block, (ablock <<= 1)*sizeof(Block));
+			}
 			block[nblock].addr = strtoul(f[1], nil, 0);
 			block[nblock].size = strtoul(f[2], nil, 0);
 			block[nblock].w0 = strtoul(f[3], nil, 0);
@@ -319,4 +327,5 @@
 				Bprint(&bio, "block 0x%.8lux 0x%.8lux 0x%.8lux 0x%.8lux %s %s\n", b->addr, b->size, b->w0, b->w1, b->s0, b->s1);
 	}
 	Bterm(&bio);
+	exits("");
 }