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Revision 9de0834663f28bee9e6b2c4647ed6128241ed26f authored by Linus Torvalds on 17 October 2006, 02:58:54 UTC, committed by Junio C Hamano on 17 October 2006, 04:27:44 UTC 
Fix hash function in xdiff library
 
Jim Mayering noticed that xdiff library took insanely long time
when comparing files with many identical lines.

This was because the hash function used in the library is broken
on 64-bit architectures and caused too many collisions.

http://thread.gmane.org/gmane.comp.version-control.git/28962/focus=28994

Acked-by: Davide Libenzi <davidel@xmaliserver.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
1 parent 6fe5b7f
Raw File
dump-cache-tree.c 
#include "cache.h"
#include "tree.h"
#include "cache-tree.h"


static void dump_one(struct cache_tree *it, const char *pfx, const char *x)
{
	if (it->entry_count < 0)
		printf("%-40s %s%s (%d subtrees)\n",
		       "invalid", x, pfx, it->subtree_nr);
	else
		printf("%s %s%s (%d entries, %d subtrees)\n",
		       sha1_to_hex(it->sha1), x, pfx,
		       it->entry_count, it->subtree_nr);
}

static int dump_cache_tree(struct cache_tree *it,
			   struct cache_tree *ref,
			   const char *pfx)
{
	int i;
	int errs = 0;

	if (!it || !ref)
		/* missing in either */
		return 0;

	if (it->entry_count < 0) {
		dump_one(it, pfx, "");
		dump_one(ref, pfx, "#(ref) ");
		if (it->subtree_nr != ref->subtree_nr)
			errs = 1;
	}
	else {
		dump_one(it, pfx, "");
		if (memcmp(it->sha1, ref->sha1, 20) ||
		    ref->entry_count != it->entry_count ||
		    ref->subtree_nr != it->subtree_nr) {
			dump_one(ref, pfx, "#(ref) ");
			errs = 1;
		}
	}

	for (i = 0; i < it->subtree_nr; i++) {
		char path[PATH_MAX];
		struct cache_tree_sub *down = it->down[i];
		struct cache_tree_sub *rdwn;

		rdwn = cache_tree_sub(ref, down->name);
		sprintf(path, "%s%.*s/", pfx, down->namelen, down->name);
		if (dump_cache_tree(down->cache_tree, rdwn->cache_tree, path))
			errs = 1;
	}
	return errs;
}

int main(int ac, char **av)
{
	struct cache_tree *another = cache_tree();
	if (read_cache() < 0)
		die("unable to read index file");
	cache_tree_update(another, active_cache, active_nr, 0, 1);
	return dump_cache_tree(active_cache_tree, another, "");
}
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