Initial implementation of new diff patch API

Replacing the `git_iterator` object, this creates a simple API
for accessing the "patch" for any file pair in a diff list and
then gives indexed access to the hunks in the patch and the lines
in the hunk.  This is the initial implementation of this revised
API - it is still broken, but at least builds cleanly.

1 files changed, 86 insertions, 0 deletions

diff --git a/src/diff_output.h b/src/diff_output.h
new file mode 100644
index 000000000..f54639088
--- /dev/null
+++ b/src/diff_output.h
@@ -0,0 +1,86 @@
+/*
+ * Copyright (C) 2009-2012 the libgit2 contributors
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+#ifndef INCLUDE_diff_output_h__
+#define INCLUDE_diff_output_h__
+
+#include "git2/blob.h"
+#include "diff.h"
+#include "map.h"
+#include "xdiff/xdiff.h"
+
+#define MAX_DIFF_FILESIZE 0x20000000
+
+enum {
+	GIT_DIFF_PATCH_ALLOCATED  = (1 << 0),
+	GIT_DIFF_PATCH_PREPPED    = (1 << 1),
+	GIT_DIFF_PATCH_LOADED     = (1 << 2),
+	GIT_DIFF_PATCH_DIFFABLE   = (1 << 3),
+	GIT_DIFF_PATCH_DIFFED     = (1 << 4),
+};
+
+/* context for performing diffs */
+typedef struct {
+	git_repository   *repo;
+	git_diff_list    *diff;
+	git_diff_options *opts;
+	git_diff_file_fn  file_cb;
+	git_diff_hunk_fn  hunk_cb;
+	git_diff_data_fn  data_cb;
+	void *cb_data;
+	int   cb_error;
+	git_diff_range cb_range;
+	xdemitconf_t xdiff_config;
+	xpparam_t    xdiff_params;
+} diff_context;
+
+/* cached information about a single span in a diff */
+typedef struct diff_patch_line diff_patch_line;
+struct diff_patch_line {
+	const char *ptr;
+	size_t len;
+	int lines, oldno, newno;
+	char origin;
+};
+
+/* cached information about a hunk in a diff */
+typedef struct diff_patch_hunk diff_patch_hunk;
+struct diff_patch_hunk {
+	git_diff_range range;
+	char   header[128];
+	size_t header_len;
+	size_t line_start;
+	size_t line_count;
+};
+
+struct git_diff_patch {
+	git_refcount rc;
+	git_diff_list *diff; /* for refcount purposes, maybe NULL for blob diffs */
+	git_diff_delta *delta;
+	diff_context *ctxt; /* only valid while generating patch */
+	git_iterator_type_t old_src;
+	git_iterator_type_t new_src;
+	git_blob *old_blob;
+	git_blob *new_blob;
+	git_map  old_data;
+	git_map  new_data;
+	uint32_t flags;
+	diff_patch_hunk *hunks;
+	size_t hunks_asize, hunks_size;
+	diff_patch_line *lines;
+	size_t lines_asize, lines_size;
+};
+
+/* context for performing diff on a single delta */
+typedef struct {
+	git_diff_patch *patch;
+	uint32_t prepped  : 1;
+	uint32_t loaded   : 1;
+	uint32_t diffable : 1;
+	uint32_t diffed   : 1;
+} diff_delta_context;
+
+#endif