Merge branch 'bc/reflog-fix' into js/reflog-delete

* bc/reflog-fix: (1490 commits)
  builtin-reflog.c: don't install new reflog on write failure
  hash: fix lookup_hash semantics
  gitweb: Better chopping in commit search results
  builtin-tag.c: remove cruft
  git-merge-index documentation: clarify synopsis
  send-email: fix In-Reply-To regression
  git-reset --hard and git-read-tree --reset: fix read_cache_unmerged()
  Teach git-grep --name-only as synonym for -l
  diff: fix java funcname pattern for solaris
  t3404: use configured shell instead of /bin/sh
  git_config_*: don't assume we are parsing a config file
  prefix_path: use is_absolute_path() instead of *orig == '/'
  git-clean: handle errors if removing files fails
  Clarified the meaning of git-add -u in the documentation
  git-clone.sh: properly configure remote even if remote's head is dangling
  git.el: Set process-environment instead of invoking env
  Documentation/git-stash: document options for git stash list
  send-email: squelch warning due to comparing undefined $_ to ""
  cvsexportcommit: be graceful when "cvs status" reorders the arguments
  Rename git-core rpm to just git and rename the meta-pacakge to git-all.
  ...

Conflicts:

	Documentation/git-reflog.txt
	t/t1410-reflog.sh

1 files changed, 43 insertions, 0 deletions

diff --git a/hash.h b/hash.h
new file mode 100644
index 0000000000..a8b0fbb5b5
--- /dev/null
+++ b/hash.h
@@ -0,0 +1,43 @@
+#ifndef HASH_H
+#define HASH_H
+
+/*
+ * These are some simple generic hash table helper functions.
+ * Not necessarily suitable for all users, but good for things
+ * where you want to just keep track of a list of things, and
+ * have a good hash to use on them.
+ *
+ * It keeps the hash table at roughly 50-75% free, so the memory
+ * cost of the hash table itself is roughly
+ *
+ *	3 * 2*sizeof(void *) * nr_of_objects
+ *
+ * bytes.
+ *
+ * FIXME: on 64-bit architectures, we waste memory. It would be
+ * good to have just 32-bit pointers, requiring a special allocator
+ * for hashed entries or something.
+ */
+struct hash_table_entry {
+	unsigned int hash;
+	void *ptr;
+};
+
+struct hash_table {
+	unsigned int size, nr;
+	struct hash_table_entry *array;
+};
+
+extern void *lookup_hash(unsigned int hash, struct hash_table *table);
+extern void **insert_hash(unsigned int hash, void *ptr, struct hash_table *table);
+extern int for_each_hash(struct hash_table *table, int (*fn)(void *));
+extern void free_hash(struct hash_table *table);
+
+static inline void init_hash(struct hash_table *table)
+{
+	table->size = 0;
+	table->nr = 0;
+	table->array = NULL;
+}
+
+#endif