[RFCv2 PATCH 2/7] ui-blame: create framework

[Jeff Smith]

Create framework for a page that will contain the 'blame' for a file
in the repository.

Signed-off-by: Jeff Smith <whydoubt at gmail.com>
---
 ui-blame.c | 160 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 ui-blame.h |   7 +++
 2 files changed, 167 insertions(+)
 create mode 100644 ui-blame.c
 create mode 100644 ui-blame.h

diff --git a/ui-blame.c b/ui-blame.c
new file mode 100644
index 0000000..901ca89
--- /dev/null
+++ b/ui-blame.c
@@ -0,0 +1,160 @@
+/* ui-blame.c: functions for blame output
+ *
+ * Copyright (C) 2006-2017 cgit Development Team <cgit at lists.zx2c4.com>
+ *
+ * Licensed under GNU General Public License v2
+ *   (see COPYING for full license text)
+ */
+
+#include "cgit.h"
+#include "ui-blame.h"
+#include "html.h"
+#include "ui-shared.h"
+
+struct walk_tree_context {
+	char *curr_rev;
+	int match_baselen;
+	int state;
+};
+
+static void set_title_from_path(const char *path)
+{
+	size_t path_len, path_index, path_last_end;
+	char *new_title;
+
+	if (!path)
+		return;
+
+	path_len = strlen(path);
+	new_title = xmalloc(path_len + 3 + strlen(ctx.page.title) + 1);
+	new_title[0] = '\0';
+
+	for (path_index = path_len, path_last_end = path_len; path_index-- > 0;) {
+		if (path[path_index] == '/') {
+			if (path_index == path_len - 1) {
+				path_last_end = path_index - 1;
+				continue;
+			}
+			strncat(new_title, &path[path_index + 1], path_last_end - path_index - 1);
+			strcat(new_title, "\\");
+			path_last_end = path_index;
+		}
+	}
+	if (path_last_end)
+		strncat(new_title, path, path_last_end);
+
+	strcat(new_title, " - ");
+	strcat(new_title, ctx.page.title);
+	ctx.page.title = new_title;
+}
+static void print_object(const unsigned char *sha1, const char *path, const char *basename, const char *rev)
+{
+	enum object_type type;
+	unsigned long size;
+
+	type = sha1_object_info(sha1, &size);
+	if (type == OBJ_BAD) {
+		cgit_print_error_page(404, "Not found", "Bad object name: %s",
+				      sha1_to_hex(sha1));
+		return;
+	}
+
+	/* Read in applicable data here */
+
+	set_title_from_path(path);
+
+	cgit_print_layout_start();
+	htmlf("blob: %s (", sha1_to_hex(sha1));
+	cgit_plain_link("plain", NULL, NULL, ctx.qry.head, rev, path);
+	html(") (");
+	cgit_tree_link("tree", NULL, NULL, ctx.qry.head, rev, path);
+	html(")\n");
+
+	if (ctx.cfg.max_blob_size && size / 1024 > ctx.cfg.max_blob_size) {
+		htmlf("<div class='error'>blob size (%ldKB) exceeds display size limit (%dKB).</div>",
+		      size / 1024, ctx.cfg.max_blob_size);
+		return;
+	}
+
+	/* Output data here */
+
+	cgit_print_layout_end();
+	return;
+}
+
+static int walk_tree(const unsigned char *sha1, struct strbuf *base,
+		     const char *pathname, unsigned mode, int stage, void *cbdata)
+{
+	struct walk_tree_context *walk_tree_ctx = cbdata;
+
+	if (base->len == walk_tree_ctx->match_baselen) {
+		if (S_ISREG(mode)) {
+			struct strbuf buffer = STRBUF_INIT;
+			strbuf_addbuf(&buffer, base);
+			strbuf_addstr(&buffer, pathname);
+			print_object(sha1, buffer.buf, pathname, walk_tree_ctx->curr_rev);
+			strbuf_release(&buffer);
+			walk_tree_ctx->state = 1;
+		} else if (S_ISDIR(mode)) {
+			walk_tree_ctx->state = 2;
+		}
+	} else if (base->len < INT_MAX && (int)base->len > walk_tree_ctx->match_baselen) {
+		walk_tree_ctx->state = 2;
+	} else if (S_ISDIR(mode)) {
+		return READ_TREE_RECURSIVE;
+	}
+	return 0;
+}
+
+static int basedir_len(const char *path)
+{
+	char *p = strrchr(path, '/');
+	if (p)
+		return p - path + 1;
+	return 0;
+}
+
+void cgit_print_blame(void)
+{
+	const char *rev = ctx.qry.sha1;
+	struct object_id oid;
+	struct commit *commit;
+	struct pathspec_item path_items = {
+		.match = ctx.qry.path,
+		.len = ctx.qry.path ? strlen(ctx.qry.path) : 0
+	};
+	struct pathspec paths = {
+		.nr = 1,
+		.items = &path_items
+	};
+	struct walk_tree_context walk_tree_ctx = {
+		.state = 0
+	};
+
+	if (!rev)
+		rev = ctx.qry.head;
+
+	if (get_oid(rev, &oid)) {
+		cgit_print_error_page(404, "Not found",
+			"Invalid revision name: %s", rev);
+		return;
+	}
+	commit = lookup_commit_reference(&oid);
+	if (!commit || parse_commit(commit)) {
+		cgit_print_error_page(404, "Not found",
+			"Invalid commit reference: %s", rev);
+		return;
+	}
+
+	walk_tree_ctx.curr_rev = xstrdup(rev);
+	walk_tree_ctx.match_baselen = (path_items.match) ?
+				       basedir_len(path_items.match) : -1;
+
+	read_tree_recursive(commit->tree, "", 0, 0, &paths, walk_tree, &walk_tree_ctx);
+	if (!walk_tree_ctx.state)
+		cgit_print_error_page(404, "Not found", "Not found");
+	else if (walk_tree_ctx.state == 2)
+		cgit_print_error_page(404, "No blame for folders", "Blame is not available for folders.");
+
+	free(walk_tree_ctx.curr_rev);
+}
diff --git a/ui-blame.h b/ui-blame.h
new file mode 100644
index 0000000..8a438e9
--- /dev/null
+++ b/ui-blame.h
@@ -0,0 +1,7 @@
+#ifndef UI_BLAME_H
+#define UI_BLAME_H
+
+extern void cgit_print_blame(void);
+
+#endif /* UI_BLAME_H */
+
-- 
2.9.4