1 files changed, 168 insertions, 0 deletions
diff --git a/bundle-uri.c b/bundle-uri.c
new file mode 100644
index 0000000000..4a8cc74ed0
--- /dev/null
+++ b/bundle-uri.c
@@ -0,0 +1,168 @@
+#include "cache.h"
+#include "bundle-uri.h"
+#include "bundle.h"
+#include "object-store.h"
+#include "refs.h"
+#include "run-command.h"
+
+static int find_temp_filename(struct strbuf *name)
+{
+	int fd;
+	/*
+	 * Find a temporary filename that is available. This is briefly
+	 * racy, but unlikely to collide.
+	 */
+	fd = odb_mkstemp(name, "bundles/tmp_uri_XXXXXX");
+	if (fd < 0) {
+		warning(_("failed to create temporary file"));
+		return -1;
+	}
+
+	close(fd);
+	unlink(name->buf);
+	return 0;
+}
+
+static int download_https_uri_to_file(const char *file, const char *uri)
+{
+	int result = 0;
+	struct child_process cp = CHILD_PROCESS_INIT;
+	FILE *child_in = NULL, *child_out = NULL;
+	struct strbuf line = STRBUF_INIT;
+	int found_get = 0;
+
+	strvec_pushl(&cp.args, "git-remote-https", uri, NULL);
+	cp.in = -1;
+	cp.out = -1;
+
+	if (start_command(&cp))
+		return 1;
+
+	child_in = fdopen(cp.in, "w");
+	if (!child_in) {
+		result = 1;
+		goto cleanup;
+	}
+
+	child_out = fdopen(cp.out, "r");
+	if (!child_out) {
+		result = 1;
+		goto cleanup;
+	}
+
+	fprintf(child_in, "capabilities\n");
+	fflush(child_in);
+
+	while (!strbuf_getline(&line, child_out)) {
+		if (!line.len)
+			break;
+		if (!strcmp(line.buf, "get"))
+			found_get = 1;
+	}
+	strbuf_release(&line);
+
+	if (!found_get) {
+		result = error(_("insufficient capabilities"));
+		goto cleanup;
+	}
+
+	fprintf(child_in, "get %s %s\n\n", uri, file);
+
+cleanup:
+	if (child_in)
+		fclose(child_in);
+	if (finish_command(&cp))
+		return 1;
+	if (child_out)
+		fclose(child_out);
+	return result;
+}
+
+static int copy_uri_to_file(const char *filename, const char *uri)
+{
+	const char *out;
+
+	if (starts_with(uri, "https:") ||
+	    starts_with(uri, "http:"))
+		return download_https_uri_to_file(filename, uri);
+
+	if (skip_prefix(uri, "file://", &out))
+		uri = out;
+
+	/* Copy as a file */
+	return copy_file(filename, uri, 0);
+}
+
+static int unbundle_from_file(struct repository *r, const char *file)
+{
+	int result = 0;
+	int bundle_fd;
+	struct bundle_header header = BUNDLE_HEADER_INIT;
+	struct string_list_item *refname;
+	struct strbuf bundle_ref = STRBUF_INIT;
+	size_t bundle_prefix_len;
+
+	if ((bundle_fd = read_bundle_header(file, &header)) < 0)
+		return 1;
+
+	if ((result = unbundle(r, &header, bundle_fd, NULL)))
+		return 1;
+
+	/*
+	 * Convert all refs/heads/ from the bundle into refs/bundles/
+	 * in the local repository.
+	 */
+	strbuf_addstr(&bundle_ref, "refs/bundles/");
+	bundle_prefix_len = bundle_ref.len;
+
+	for_each_string_list_item(refname, &header.references) {
+		struct object_id *oid = refname->util;
+		struct object_id old_oid;
+		const char *branch_name;
+		int has_old;
+
+		if (!skip_prefix(refname->string, "refs/heads/", &branch_name))
+			continue;
+
+		strbuf_setlen(&bundle_ref, bundle_prefix_len);
+		strbuf_addstr(&bundle_ref, branch_name);
+
+		has_old = !read_ref(bundle_ref.buf, &old_oid);
+		update_ref("fetched bundle", bundle_ref.buf, oid,
+			   has_old ? &old_oid : NULL,
+			   REF_SKIP_OID_VERIFICATION,
+			   UPDATE_REFS_MSG_ON_ERR);
+	}
+
+	bundle_header_release(&header);
+	return result;
+}
+
+int fetch_bundle_uri(struct repository *r, const char *uri)
+{
+	int result = 0;
+	struct strbuf filename = STRBUF_INIT;
+
+	if ((result = find_temp_filename(&filename)))
+		goto cleanup;
+
+	if ((result = copy_uri_to_file(filename.buf, uri))) {
+		warning(_("failed to download bundle from URI '%s'"), uri);
+		goto cleanup;
+	}
+
+	if ((result = !is_bundle(filename.buf, 0))) {
+		warning(_("file at URI '%s' is not a bundle"), uri);
+		goto cleanup;
+	}
+
+	if ((result = unbundle_from_file(r, filename.buf))) {
+		warning(_("failed to unbundle bundle from URI '%s'"), uri);
+		goto cleanup;
+	}
+
+cleanup:
+	unlink(filename.buf);
+	strbuf_release(&filename);
+	return result;
+}