1 files changed, 338 insertions, 0 deletions
diff --git a/src/libgit2/fetchhead.c b/src/libgit2/fetchhead.c
new file mode 100644
index 000000000..6511124ef
--- /dev/null
+++ b/src/libgit2/fetchhead.c
@@ -0,0 +1,338 @@
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+
+#include "fetchhead.h"
+
+#include "git2/types.h"
+#include "git2/oid.h"
+
+#include "str.h"
+#include "futils.h"
+#include "filebuf.h"
+#include "refs.h"
+#include "net.h"
+#include "repository.h"
+
+int git_fetchhead_ref_cmp(const void *a, const void *b)
+{
+	const git_fetchhead_ref *one = (const git_fetchhead_ref *)a;
+	const git_fetchhead_ref *two = (const git_fetchhead_ref *)b;
+
+	if (one->is_merge && !two->is_merge)
+		return -1;
+	if (two->is_merge && !one->is_merge)
+		return 1;
+
+	if (one->ref_name && two->ref_name)
+		return strcmp(one->ref_name, two->ref_name);
+	else if (one->ref_name)
+		return -1;
+	else if (two->ref_name)
+		return 1;
+
+	return 0;
+}
+
+static char *sanitized_remote_url(const char *remote_url)
+{
+	git_net_url url = GIT_NET_URL_INIT;
+	char *sanitized = NULL;
+	int error;
+
+	if (git_net_url_parse(&url, remote_url) == 0) {
+		git_str buf = GIT_STR_INIT;
+
+		git__free(url.username);
+		git__free(url.password);
+		url.username = url.password = NULL;
+
+		if ((error = git_net_url_fmt(&buf, &url)) < 0)
+			goto fallback;
+
+		sanitized = git_str_detach(&buf);
+	}
+
+fallback:
+	if (!sanitized)
+		sanitized = git__strdup(remote_url);
+
+	git_net_url_dispose(&url);
+	return sanitized;
+}
+
+int git_fetchhead_ref_create(
+	git_fetchhead_ref **out,
+	git_oid *oid,
+	unsigned int is_merge,
+	const char *ref_name,
+	const char *remote_url)
+{
+	git_fetchhead_ref *fetchhead_ref;
+
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(oid);
+
+	*out = NULL;
+
+	fetchhead_ref = git__malloc(sizeof(git_fetchhead_ref));
+	GIT_ERROR_CHECK_ALLOC(fetchhead_ref);
+
+	memset(fetchhead_ref, 0x0, sizeof(git_fetchhead_ref));
+
+	git_oid_cpy(&fetchhead_ref->oid, oid);
+	fetchhead_ref->is_merge = is_merge;
+
+	if (ref_name) {
+		fetchhead_ref->ref_name = git__strdup(ref_name);
+		GIT_ERROR_CHECK_ALLOC(fetchhead_ref->ref_name);
+	}
+
+	if (remote_url) {
+		fetchhead_ref->remote_url = sanitized_remote_url(remote_url);
+		GIT_ERROR_CHECK_ALLOC(fetchhead_ref->remote_url);
+	}
+
+	*out = fetchhead_ref;
+
+	return 0;
+}
+
+static int fetchhead_ref_write(
+	git_filebuf *file,
+	git_fetchhead_ref *fetchhead_ref)
+{
+	char oid[GIT_OID_HEXSZ + 1];
+	const char *type, *name;
+	int head = 0;
+
+	GIT_ASSERT_ARG(file);
+	GIT_ASSERT_ARG(fetchhead_ref);
+
+	git_oid_fmt(oid, &fetchhead_ref->oid);
+	oid[GIT_OID_HEXSZ] = '\0';
+
+	if (git__prefixcmp(fetchhead_ref->ref_name, GIT_REFS_HEADS_DIR) == 0) {
+		type = "branch ";
+		name = fetchhead_ref->ref_name + strlen(GIT_REFS_HEADS_DIR);
+	} else if(git__prefixcmp(fetchhead_ref->ref_name,
+		GIT_REFS_TAGS_DIR) == 0) {
+		type = "tag ";
+		name = fetchhead_ref->ref_name + strlen(GIT_REFS_TAGS_DIR);
+	} else if (!git__strcmp(fetchhead_ref->ref_name, GIT_HEAD_FILE)) {
+		head = 1;
+	} else {
+		type = "";
+		name = fetchhead_ref->ref_name;
+	}
+
+	if (head)
+		return git_filebuf_printf(file, "%s\t\t%s\n", oid, fetchhead_ref->remote_url);
+
+	return git_filebuf_printf(file, "%s\t%s\t%s'%s' of %s\n",
+		oid,
+		(fetchhead_ref->is_merge) ? "" : "not-for-merge",
+		type,
+		name,
+		fetchhead_ref->remote_url);
+}
+
+int git_fetchhead_write(git_repository *repo, git_vector *fetchhead_refs)
+{
+	git_filebuf file = GIT_FILEBUF_INIT;
+	git_str path = GIT_STR_INIT;
+	unsigned int i;
+	git_fetchhead_ref *fetchhead_ref;
+
+	GIT_ASSERT_ARG(repo);
+	GIT_ASSERT_ARG(fetchhead_refs);
+
+	if (git_str_joinpath(&path, repo->gitdir, GIT_FETCH_HEAD_FILE) < 0)
+		return -1;
+
+	if (git_filebuf_open(&file, path.ptr, GIT_FILEBUF_APPEND, GIT_REFS_FILE_MODE) < 0) {
+		git_str_dispose(&path);
+		return -1;
+	}
+
+	git_str_dispose(&path);
+
+	git_vector_sort(fetchhead_refs);
+
+	git_vector_foreach(fetchhead_refs, i, fetchhead_ref)
+		fetchhead_ref_write(&file, fetchhead_ref);
+
+	return git_filebuf_commit(&file);
+}
+
+static int fetchhead_ref_parse(
+	git_oid *oid,
+	unsigned int *is_merge,
+	git_str *ref_name,
+	const char **remote_url,
+	char *line,
+	size_t line_num)
+{
+	char *oid_str, *is_merge_str, *desc, *name = NULL;
+	const char *type = NULL;
+	int error = 0;
+
+	*remote_url = NULL;
+
+	if (!*line) {
+		git_error_set(GIT_ERROR_FETCHHEAD,
+			"empty line in FETCH_HEAD line %"PRIuZ, line_num);
+		return -1;
+	}
+
+	/* Compat with old git clients that wrote FETCH_HEAD like a loose ref. */
+	if ((oid_str = git__strsep(&line, "\t")) == NULL) {
+		oid_str = line;
+		line += strlen(line);
+
+		*is_merge = 1;
+	}
+
+	if (strlen(oid_str) != GIT_OID_HEXSZ) {
+		git_error_set(GIT_ERROR_FETCHHEAD,
+			"invalid object ID in FETCH_HEAD line %"PRIuZ, line_num);
+		return -1;
+	}
+
+	if (git_oid_fromstr(oid, oid_str) < 0) {
+		const git_error *oid_err = git_error_last();
+		const char *err_msg = oid_err ? oid_err->message : "invalid object ID";
+
+		git_error_set(GIT_ERROR_FETCHHEAD, "%s in FETCH_HEAD line %"PRIuZ,
+			err_msg, line_num);
+		return -1;
+	}
+
+	/* Parse new data from newer git clients */
+	if (*line) {
+		if ((is_merge_str = git__strsep(&line, "\t")) == NULL) {
+			git_error_set(GIT_ERROR_FETCHHEAD,
+				"invalid description data in FETCH_HEAD line %"PRIuZ, line_num);
+			return -1;
+		}
+
+		if (*is_merge_str == '\0')
+			*is_merge = 1;
+		else if (strcmp(is_merge_str, "not-for-merge") == 0)
+			*is_merge = 0;
+		else {
+			git_error_set(GIT_ERROR_FETCHHEAD,
+				"invalid for-merge entry in FETCH_HEAD line %"PRIuZ, line_num);
+			return -1;
+		}
+
+		if ((desc = line) == NULL) {
+			git_error_set(GIT_ERROR_FETCHHEAD,
+				"invalid description in FETCH_HEAD line %"PRIuZ, line_num);
+			return -1;
+		}
+
+		if (git__prefixcmp(desc, "branch '") == 0) {
+			type = GIT_REFS_HEADS_DIR;
+			name = desc + 8;
+		} else if (git__prefixcmp(desc, "tag '") == 0) {
+			type = GIT_REFS_TAGS_DIR;
+			name = desc + 5;
+		} else if (git__prefixcmp(desc, "'") == 0)
+			name = desc + 1;
+
+		if (name) {
+			if ((desc = strstr(name, "' ")) == NULL ||
+				git__prefixcmp(desc, "' of ") != 0) {
+				git_error_set(GIT_ERROR_FETCHHEAD,
+					"invalid description in FETCH_HEAD line %"PRIuZ, line_num);
+				return -1;
+			}
+
+			*desc = '\0';
+			desc += 5;
+		}
+
+		*remote_url = desc;
+	}
+
+	git_str_clear(ref_name);
+
+	if (type)
+		git_str_join(ref_name, '/', type, name);
+	else if(name)
+		git_str_puts(ref_name, name);
+
+	return error;
+}
+
+int git_repository_fetchhead_foreach(git_repository *repo,
+	git_repository_fetchhead_foreach_cb cb,
+	void *payload)
+{
+	git_str path = GIT_STR_INIT, file = GIT_STR_INIT, name = GIT_STR_INIT;
+	const char *ref_name;
+	git_oid oid;
+	const char *remote_url;
+	unsigned int is_merge = 0;
+	char *buffer, *line;
+	size_t line_num = 0;
+	int error = 0;
+
+	GIT_ASSERT_ARG(repo);
+	GIT_ASSERT_ARG(cb);
+
+	if (git_str_joinpath(&path, repo->gitdir, GIT_FETCH_HEAD_FILE) < 0)
+		return -1;
+
+	if ((error = git_futils_readbuffer(&file, git_str_cstr(&path))) < 0)
+		goto done;
+
+	buffer = file.ptr;
+
+	while ((line = git__strsep(&buffer, "\n")) != NULL) {
+		++line_num;
+
+		if ((error = fetchhead_ref_parse(
+				&oid, &is_merge, &name, &remote_url, line, line_num)) < 0)
+			goto done;
+
+		if (git_str_len(&name) > 0)
+			ref_name = git_str_cstr(&name);
+		else
+			ref_name = NULL;
+
+		error = cb(ref_name, remote_url, &oid, is_merge, payload);
+		if (error) {
+			git_error_set_after_callback(error);
+			goto done;
+		}
+	}
+
+	if (*buffer) {
+		git_error_set(GIT_ERROR_FETCHHEAD, "no EOL at line %"PRIuZ, line_num+1);
+		error = -1;
+		goto done;
+	}
+
+done:
+	git_str_dispose(&file);
+	git_str_dispose(&path);
+	git_str_dispose(&name);
+
+	return error;
+}
+
+void git_fetchhead_ref_free(git_fetchhead_ref *fetchhead_ref)
+{
+	if (fetchhead_ref == NULL)
+		return;
+
+	git__free(fetchhead_ref->remote_url);
+	git__free(fetchhead_ref->ref_name);
+	git__free(fetchhead_ref);
+}
+