X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=diff-delta.c;h=51df4608a8186e519bcb3b4e67d421c18efb696a;hb=4b4a5dbb17e1136275665024689625ed5cc5a03d;hp=8b9172aa2ef7402b0a847815bb11a26d1c4444fe;hpb=b879de1812f390e20f5ac7eb3aad9f83db02fae1;p=git.git

diff --git a/diff-delta.c b/diff-delta.c
index 8b9172aa2..51df4608a 100644
--- a/diff-delta.c
+++ b/diff-delta.c
@@ -148,11 +148,11 @@ struct delta_index * create_delta_index(const void *buf, unsigned long bufsize)
 		return NULL;
 
 	/* Determine index hash size.  Note that indexing skips the
-	   first byte to allow for optimizing the rabin polynomial
+	   first byte to allow for optimizing the Rabin's polynomial
 	   initialization in create_delta(). */
 	entries = (bufsize - 1)  / RABIN_WINDOW;
 	hsize = entries / 4;
-	for (i = 4; (1 << i) < hsize && i < 31; i++);
+	for (i = 4; (1u << i) < hsize && i < 31; i++);
 	hsize = 1 << i;
 	hmask = hsize - 1;
 
@@ -205,7 +205,7 @@ struct delta_index * create_delta_index(const void *buf, unsigned long bufsize)
 
 	/*
 	 * Determine a limit on the number of entries in the same hash
-	 * bucket.  This guard us against patological data sets causing
+	 * bucket.  This guards us against pathological data sets causing
 	 * really bad hash distribution with most entries in the same hash
 	 * bucket that would bring us to O(m*n) computing costs (m and n
 	 * corresponding to reference and target buffer sizes).
@@ -240,7 +240,7 @@ void free_delta_index(struct delta_index *index)
 
 /*
  * The maximum size for any opcode sequence, including the initial header
- * plus rabin window plus biggest copy.
+ * plus Rabin window plus biggest copy.
  */
 #define MAX_OP_SIZE	(5 + 5 + 1 + RABIN_WINDOW + 7)
 
@@ -308,8 +308,8 @@ create_delta(const struct delta_index *index,
 				continue;
 			if (ref_size > top - src)
 				ref_size = top - src;
-			if (ref_size > 0x10000)
-				ref_size = 0x10000;
+			if (ref_size > 0xffffff)
+				ref_size = 0xffffff;
 			if (ref_size <= msize)
 				break;
 			while (ref_size-- && *src++ == *ref)
@@ -318,6 +318,8 @@ create_delta(const struct delta_index *index,
 				/* this is our best match so far */
 				msize = ref - entry->ptr;
 				moff = entry->ptr - ref_data;
+				if (msize >= 0x10000)
+					break;  /* this is good enough */
 			}
 		}
 
@@ -381,6 +383,8 @@ create_delta(const struct delta_index *index,
 			if (msize & 0xff) { out[outpos++] = msize; i |= 0x10; }
 			msize >>= 8;
 			if (msize & 0xff) { out[outpos++] = msize; i |= 0x20; }
+			msize >>= 8;
+			if (msize & 0xff) { out[outpos++] = msize; i |= 0x40; }
 
 			*op = i;
 		}
@@ -392,7 +396,7 @@ create_delta(const struct delta_index *index,
 				outsize = max_size + MAX_OP_SIZE + 1;
 			if (max_size && outpos > max_size)
 				break;
-			out = realloc(out, outsize);
+			out = xrealloc(out, outsize);
 			if (!out) {
 				free(tmp);
 				return NULL;