sparse-index: pass string length to index_file_exists()

The call to index_file_exists() in the loop in expand_to_path() passes
the wrong string length.  Let's fix that.

The loop in expand_to_path() searches the name-hash for each
sub-directory prefix in the provided pathname. That is, by searching
for "dir1/" then "dir1/dir2/" then "dir1/dir2/dir3/" and so on until
it finds a cache-entry representing a sparse directory.

The code creates "strbuf path_mutable" to contain the working pathname
and modifies the buffer in-place by temporarily replacing the character
following each successive "/" with NUL for the duration of the call to
index_file_exists().

It does not update the strbuf.len during this substitution.

Pass the patched length of the prefix path instead.

Signed-off-by: Jeff Hostetler <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: jeffhostetler

sparse-index.c

@@ -326,8 +326,9 @@ void expand_to_path(struct index_state *istate,
 		replace++;
 		temp = *replace;
 		*replace = '\0';
+		substr_len = replace - path_mutable.buf;
 		if (index_file_exists(istate, path_mutable.buf,
-				      path_mutable.len, icase)) {
+				      substr_len, icase)) {
 			/*
 			 * We found a parent directory in the name-hash
 			 * hashtable, because only sparse directory entries
@@ -340,7 +341,6 @@ void expand_to_path(struct index_state *istate,
 		}
 
 		*replace = temp;
-		substr_len = replace - path_mutable.buf;
 	}
 
 cleanup: