Cloud storage: sync the remote after save

This change once again tests if the remote can be reached. Even with a
fairly big data file and a medium speed internet connection the remote
sync is fast enough to call it nearly instantaneous. Maybe a couple of
seconds.

We may need more checks / different heuristics / warnings if the sync
didn't happen, etc. But for now this should allow more reasonable testing.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

dive.h

@@ -671,8 +671,9 @@ extern void save_one_dive_to_mb(struct membuffer *b, struct dive *dive);
 struct git_oid;
 struct git_repository;
 #define dummy_git_repository ((git_repository *)3ul) /* Random bogus pointer, not NULL */
-extern struct git_repository *is_git_repository(const char *filename, const char **branchp);
+extern struct git_repository *is_git_repository(const char *filename, const char **branchp, const char **remote);
-extern int git_save_dives(struct git_repository *, const char *, bool select_only);
+extern int sync_with_remote(struct git_repository *repo, const char *remote, const char *branch);
+extern int git_save_dives(struct git_repository *, const char *, const char *remote, bool select_only);
 extern int git_load_dives(struct git_repository *, const char *);
 extern const char *saved_git_id;
 extern void clear_git_id(void);

file.c

@@ -425,7 +425,7 @@ int parse_file(const char *filename)
 	char *fmt;
 	int ret;
 
-	git = is_git_repository(filename, &branch);
+	git = is_git_repository(filename, &branch, NULL);
 	if (git && !git_load_dives(git, branch))
 		return 0;
 

git-access.c

@@ -216,21 +216,14 @@ static int check_remote_status(git_repository *repo, git_remote *origin, const c
 	git_reference_free(remote_ref);
 }
 
-static git_repository *update_local_repo(const char *localdir, const char *remote, const char *branch)
+int sync_with_remote(git_repository *repo, const char *remote, const char *branch)
 {
 	int error;
-	git_repository *repo = NULL;
 	git_remote *origin;
 	enum remote_type rt;
 	char *proxy_string;
 	git_config *conf;
 
-	error = git_repository_open(&repo, localdir);
-	if (error) {
-		report_error("Unable to open git cache repository at %s: %s",
-			localdir, giterr_last()->message);
-		return NULL;
-	}
 	if (strncmp(remote, "ssh://", 6) == 0)
 		rt = SSH;
 	else if (strncmp(remote, "https://", 8) == 0)
@@ -254,11 +247,11 @@ static git_repository *update_local_repo(const char *localdir, const char *remot
 	if (error) {
 		report_error("Repository '%s' origin lookup failed (%s)",
 			remote, giterr_last()->message);
-		return repo;
+		return 0;
 	}
 
 	if (rt == HTTPS && !canReachCloudServer())
-		return repo;
+		return 0;
 #if USE_LIBGIT23_API
 	git_fetch_options opts = GIT_FETCH_OPTIONS_INIT;
 	if (rt == SSH)
@@ -276,6 +269,20 @@ static git_repository *update_local_repo(const char *localdir, const char *remot
 		check_remote_status(repo, origin, branch, rt);
 
 	git_remote_free(origin);
+}
+
+static git_repository *update_local_repo(const char *localdir, const char *remote, const char *branch)
+{
+	int error;
+	git_repository *repo = NULL;
+
+	error = git_repository_open(&repo, localdir);
+	if (error) {
+		report_error("Unable to open git cache repository at %s: %s",
+			localdir, giterr_last()->message);
+		return NULL;
+	}
+	sync_with_remote(repo, remote, branch);
 	return repo;
 }
 
@@ -393,7 +400,7 @@ static struct git_repository *is_remote_git_repository(char *remote, const char
 /*
  * If it's not a git repo, return NULL. Be very conservative.
  */
-struct git_repository *is_git_repository(const char *filename, const char **branchp)
+struct git_repository *is_git_repository(const char *filename, const char **branchp, const char **remote)
 {
 	int flen, blen, ret;
 	int offset = 1;
@@ -446,6 +453,9 @@ struct git_repository *is_git_repository(const char *filename, const char **bran
 
 	repo = is_remote_git_repository(loc, branch);
 	if (repo) {
+		if (remote)
+			*remote = loc;
+		else
 			free(loc);
 		*branchp = branch;
 		return repo;

save-git.c

@@ -1115,7 +1115,7 @@ static int write_git_tree(git_repository *repo, struct dir *tree, git_oid *resul
 	return ret;
 }
 
-static int do_git_save(git_repository *repo, const char *branch, bool select_only)
+static int do_git_save(git_repository *repo, const char *branch, const char *remote, bool select_only)
 {
 	struct dir tree;
 	git_oid id;
@@ -1134,16 +1134,24 @@ static int do_git_save(git_repository *repo, const char *branch, bool select_onl
 		return report_error("git tree write failed");
 
 	/* And save the tree! */
-	return create_new_commit(repo, branch, &id);
+	if (create_new_commit(repo, branch, &id))
+		return report_error("creating commit failed");
+
+	if (prefs.cloud_background_sync) {
+		/* now sync the tree with the cloud server */
+		if (strstr(remote, "https://cloud.subsurface-divelog.org")) {
+			sync_with_remote(repo, remote, branch);
+		}
+	}
 }
 
-int git_save_dives(struct git_repository *repo, const char *branch, bool select_only)
+int git_save_dives(struct git_repository *repo, const char *branch, const char *remote, bool select_only)
 {
 	int ret;
 
 	if (repo == dummy_git_repository)
 		return report_error("Unable to open git repository '%s'", branch);
-	ret = do_git_save(repo, branch, select_only);
+	ret = do_git_save(repo, branch, remote, select_only);
 	git_repository_free(repo);
 	free((void *)branch);
 	return ret;

save-xml.c

@@ -637,12 +637,12 @@ int save_dives_logic(const char *filename, const bool select_only)
 	struct membuffer buf = { 0 };
 	FILE *f;
 	void *git;
-	const char *branch;
+	const char *branch, *remote;
 	int error;
 
-	git = is_git_repository(filename, &branch);
+	git = is_git_repository(filename, &branch, &remote);
 	if (git)
-		return git_save_dives(git, branch, select_only);
+		return git_save_dives(git, branch, remote, select_only);
 
 	try_to_backup(filename);