Add an action for chdir

Added a toggle for gravity, now turned off by default.

sdn.cpp

@@ -114,7 +114,7 @@ fun needs_shell_quoting (const string &v) -> bool {
 	for (auto c : v)
 		if (strchr ("|&;<>()$`\\\"' \t\n" "*?[#˜=%" "!", c))
 			return true;
-	return false;
+	return v.empty ();
 }
 
 fun shell_escape (const string &v) -> string {
@@ -130,6 +130,59 @@ fun shell_escape (const string &v) -> string {
 	return "'" + result + "'";
 }
 
+fun parse_line (istream &is, vector<string> &out) -> bool {
+	enum {STA, DEF, COM, ESC, WOR, QUO, STATES};
+	enum {TAKE = 1 << 3, PUSH = 1 << 4, STOP = 1 << 5, ERROR = 1 << 6};
+	enum {TWOR = TAKE | WOR};
+
+	// We never transition back to the start state, so it can stay as a noop
+	static char table[STATES][7] = {
+	// state   EOF          SP, TAB     '     #     \     LF           default
+	/* STA */ {ERROR,       DEF,        QUO,  COM,  ESC,  STOP,        TWOR},
+	/* DEF */ {STOP,        0,          QUO,  COM,  ESC,  STOP,        TWOR},
+	/* COM */ {STOP,        0,          0,    0,    0,    STOP,        0},
+	/* ESC */ {ERROR,       TWOR,       TWOR, TWOR, TWOR, TWOR,        TWOR},
+	/* WOR */ {STOP | PUSH, DEF | PUSH, QUO,  TAKE, ESC,  STOP | PUSH, TAKE},
+	/* QUO */ {ERROR,       TAKE,       WOR,  TAKE, TAKE, TAKE,        TAKE},
+	};
+
+	out.clear (); string token; int state = STA;
+	constexpr auto eof = istream::traits_type::eof ();
+	while (1) {
+		int ch = is.get (), edge = 0;
+		switch (ch) {
+		case eof:  edge = table[state][0]; break;
+		case '\t':
+		case ' ':  edge = table[state][1]; break;
+		case '\'': edge = table[state][2]; break;
+		case '#':  edge = table[state][3]; break;
+		case '\\': edge = table[state][4]; break;
+		case '\n': edge = table[state][5]; break;
+		default:   edge = table[state][6]; break;
+		}
+		if (edge & TAKE)
+			token += ch;
+		if (edge & PUSH) {
+			out.push_back (token);
+			token.clear ();
+		}
+		if (edge & STOP)
+			return true;
+		if (edge & ERROR)
+			return false;
+		if (edge &= 7)
+			state = edge;
+	}
+}
+
+fun write_line (ostream &os, const vector<string> &in) {
+	if (!in.empty ())
+		os << shell_escape (in.at (0));
+	for (size_t i = 1; i < in.size (); i++)
+		os << " " << shell_escape (in.at (i));
+	os << endl;
+}
+
 fun decode_type (mode_t m) -> wchar_t {
 	if (S_ISDIR  (m)) return L'd'; if (S_ISBLK  (m)) return L'b';
 	if (S_ISCHR  (m)) return L'c'; if (S_ISLNK  (m)) return L'l';
@@ -149,8 +202,7 @@ fun decode_mode (mode_t m) -> wstring {
 		((m & S_ISGID) ? L"sS" : L"x-")[!(m & S_IXGRP)],
 		L"r-"[!(m & S_IROTH)],
 		L"w-"[!(m & S_IWOTH)],
-		((m & S_ISVTX) ? L"tT" : L"x-")[!(m & S_IXOTH)],
+		((m & S_ISVTX) ? L"tT" : L"x-")[!(m & S_IXOTH)]};
-	};
 }
 
 template<class T> fun shift (vector<T> &v) -> T {
@@ -191,12 +243,23 @@ fun xdg_config_find (const string &suffix) -> unique_ptr<ifstream> {
 	for (const auto &dir : dirs) {
 		if (dir[0] != '/')
 			continue;
-		if (ifstream ifs {dir + suffix})
+		if (ifstream ifs {dir + "/" PROJECT_NAME "/" + suffix})
 			return make_unique<ifstream> (move (ifs));
 	}
 	return nullptr;
 }
 
+fun xdg_config_write (const string &suffix) -> unique_ptr<fstream> {
+	auto dir = xdg_config_home ();
+	if (dir[0] == '/') {
+		// TODO: try to create the end directory
+		if (fstream fs {dir + "/" PROJECT_NAME "/" + suffix,
+			fstream::in | fstream::out | fstream::trunc})
+			return make_unique<fstream> (move (fs));
+	}
+	return nullptr;
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 
 using ncstring = basic_string<cchar_t>;
@@ -307,7 +370,7 @@ enum { ALT = 1 << 24, SYM = 1 << 25 };  // Outside the range of Unicode
 
 #define ACTIONS(XX) XX(NONE) XX(CHOOSE) XX(CHOOSE_FULL) XX(HELP) XX(QUIT) \
 	XX(UP) XX(DOWN) XX(TOP) XX(BOTTOM) XX(PAGE_PREVIOUS) XX(PAGE_NEXT) \
-	XX(SCROLL_UP) XX(SCROLL_DOWN) XX(GO_START) XX(GO_HOME) \
+	XX(SCROLL_UP) XX(SCROLL_DOWN) XX(CHDIR) XX(GO_START) XX(GO_HOME) \
 	XX(SEARCH) XX(RENAME) XX(RENAME_PREFILL) \
 	XX(TOGGLE_FULL) XX(REDRAW) XX(RELOAD) \
 	XX(INPUT_ABORT) XX(INPUT_CONFIRM) XX(INPUT_B_DELETE)
@@ -320,7 +383,7 @@ enum action { ACTIONS(XX) ACTION_COUNT };
 static const char *g_action_names[] = {ACTIONS(XX)};
 #undef XX
 
-static map<wint_t, action> g_normal_actions = {
+static map<wint_t, action> g_normal_actions {
 	{ALT | '\r', ACTION_CHOOSE_FULL}, {ALT | KEY (ENTER), ACTION_CHOOSE_FULL},
 	{'\r', ACTION_CHOOSE}, {KEY (ENTER), ACTION_CHOOSE}, {'h', ACTION_HELP},
 	// M-o ought to be the same shortcut the navigator is launched with
@@ -331,18 +394,18 @@ static map<wint_t, action> g_normal_actions = {
 	{'G', ACTION_BOTTOM}, {ALT | '>', ACTION_BOTTOM}, {KEY(END), ACTION_BOTTOM},
 	{KEY (PPAGE), ACTION_PAGE_PREVIOUS}, {KEY (NPAGE), ACTION_PAGE_NEXT},
 	{CTRL 'y', ACTION_SCROLL_UP}, {CTRL 'e', ACTION_SCROLL_DOWN},
-	{'&', ACTION_GO_START}, {'~', ACTION_GO_HOME},
+	{'c', ACTION_CHDIR}, {'&', ACTION_GO_START}, {'~', ACTION_GO_HOME},
 	{'/', ACTION_SEARCH},  {'s', ACTION_SEARCH},
 	{ALT | 'e', ACTION_RENAME_PREFILL}, {'e', ACTION_RENAME},
 	{'t', ACTION_TOGGLE_FULL}, {ALT | 't', ACTION_TOGGLE_FULL},
 	{CTRL 'L', ACTION_REDRAW}, {'r', ACTION_RELOAD},
 };
-static map<wint_t, action> g_input_actions = {
+static map<wint_t, action> g_input_actions {
 	{27, ACTION_INPUT_ABORT}, {CTRL 'g', ACTION_INPUT_ABORT},
 	{L'\r', ACTION_INPUT_CONFIRM}, {KEY (ENTER), ACTION_INPUT_CONFIRM},
 	{KEY (BACKSPACE), ACTION_INPUT_B_DELETE},
 };
-static const map<string, map<wint_t, action>*> g_binding_contexts = {
+static const map<string, map<wint_t, action>*> g_binding_contexts {
 	{"normal", &g_normal_actions}, {"input", &g_input_actions},
 };
 
@@ -395,8 +458,12 @@ static struct {
 	vector<level> levels;               ///< Upper directory levels
 	int offset, cursor;                 ///< Scroll offset and cursor position
 	bool full_view;                     ///< Show extended information
+	bool gravity;                       ///< Entries are shoved to the bottom
 	int max_widths[entry::COLUMNS];     ///< Column widths
 
+	wstring message;                    ///< Message for the user
+	int message_ttl;                    ///< Time to live for the message
+
 	string chosen;                      ///< Chosen item for the command line
 	bool chosen_full;                   ///< Use the full path
 
@@ -581,7 +648,7 @@ fun update () {
 		auto index = g.offset + i;
 		bool selected = index == g.cursor;
 		attrset (selected ? g.attrs[g.AT_CURSOR] : 0);
-		move (available - used + i, 0);
+		move (g.gravity ? (available - used + i) : i, 0);
 
 		auto used = 0;
 		for (int col = start_column; col < entry::COLUMNS; col++) {
@@ -603,13 +670,16 @@ fun update () {
 	hline (' ', COLS - print (bar, COLS));
 
 	attrset (g.attrs[g.AT_INPUT]);
+	curs_set (0);
 	if (g.editor) {
 		move (LINES - 1, 0);
 		auto p = apply_attrs (wstring (g.editor) + L": ", 0);
 		move (LINES - 1, print (p + apply_attrs (g.editor_line, 0), COLS - 1));
 		curs_set (1);
-	} else
+	} else if (!g.message.empty ()) {
-		curs_set (0);
+		move (LINES - 1, 0);
+		print (apply_attrs (g.message, 0), COLS);
+	}
 
 	refresh ();
 }
@@ -654,7 +724,11 @@ fun reload () {
 		(IN_ALL_EVENTS | IN_ONLYDIR | IN_EXCL_UNLINK) & ~(IN_ACCESS | IN_OPEN));
 }
 
-// TODO: we should be able to signal failures to the user
+fun show_message (const string &message, int ttl = 30) {
+	g.message = to_wide (message);
+	g.message_ttl = ttl;
+}
+
 fun run_pager (FILE *contents) {
 	// We don't really need to set O_CLOEXEC, so we're not going to
 	rewind (contents);
@@ -735,25 +809,11 @@ fun search (const wstring &needle) {
 fun is_ancestor_dir (const string &ancestor, const string &of) -> bool {
 	if (strncmp (ancestor.c_str (), of.c_str (), ancestor.length ()))
 		return false;
-	return of.c_str ()[ancestor.length ()] == '/'
+	return of[ancestor.length ()] == '/' || (ancestor == "/" && ancestor != of);
-		|| (ancestor == "/" && ancestor != of);
 }
 
-fun change_dir (const string &path) {
+fun pop_levels () {
-	if (chdir (path.c_str ())) {
+	string anchor; auto i = g.levels.rbegin ();
-		beep ();
-		return;
-	}
-
-	level last {g.offset, g.cursor, g.cwd, g.entries[g.cursor].filename};
-	reload ();
-
-	if (is_ancestor_dir (last.path, g.cwd)) {
-		g.levels.push_back (last);
-		g.offset = g.cursor = 0;
-	} else {
-		string anchor;
-		auto i = g.levels.rbegin ();
 	while (i != g.levels.rend () && !is_ancestor_dir (i->path, g.cwd)) {
 		if (i->path == g.cwd) {
 			g.offset = i->offset;
@@ -767,6 +827,23 @@ fun change_dir (const string &path) {
 	 || g.entries[g.cursor].filename != anchor))
 		search (to_wide (anchor));
 }
+
+fun change_dir (const string &path) {
+	if (chdir (path.c_str ())) {
+		show_message (strerror (errno));
+		beep ();
+		return;
+	}
+
+	level last {g.offset, g.cursor, g.cwd, g.entries[g.cursor].filename};
+	reload ();
+
+	if (is_ancestor_dir (last.path, g.cwd)) {
+		g.levels.push_back (last);
+		g.offset = g.cursor = 0;
+	} else {
+		pop_levels ();
+	}
 }
 
 fun choose (const entry &entry) -> bool {
@@ -858,6 +935,12 @@ fun handle (wint_t c) -> bool {
 		g.offset--;
 		break;
 
+	case ACTION_CHDIR:
+		g.editor = L"chdir";
+		g.editor_on_confirm = [] {
+			change_dir (to_mb (g.editor_line));
+		};
+		break;
 	case ACTION_GO_START:
 		change_dir (g.start_dir);
 		break;
@@ -1003,14 +1086,13 @@ fun load_colors () {
 	if (const char *colors = getenv ("LS_COLORS"))
 		load_ls_colors (split (colors, ":"));
 
-	auto config = xdg_config_find ("/" PROJECT_NAME "/look");
+	auto config = xdg_config_find ("look");
 	if (!config)
 		return;
 
-	string line;
+	vector<string> tokens;
-	while (getline (*config, line)) {
+	while (parse_line (*config, tokens)) {
-		auto tokens = split (line, " ");
+		if (tokens.empty ())
-		if (tokens.empty () || line.front () == '#')
 			continue;
 		auto name = shift (tokens);
 		for (int i = 0; i < g.AT_COUNT; i++)
@@ -1091,7 +1173,7 @@ fun load_bindings () {
 		learn_named_key (filtered, SYM | kc);
 	}
 
-	auto config = xdg_config_find ("/" PROJECT_NAME "/bindings");
+	auto config = xdg_config_find ("bindings");
 	if (!config)
 		return;
 
@@ -1106,10 +1188,9 @@ fun load_bindings () {
 		actions[name] = action (a++);
 	}
 
-	string line;
+	vector<string> tokens;
-	while (getline (*config, line)) {
+	while (parse_line (*config, tokens)) {
-		auto tokens = split (line, " ");
+		if (tokens.empty ())
-		if (tokens.empty () || line.front () == '#')
 			continue;
 		if (tokens.size () < 3) {
 			cerr << "bindings: expected: context binding action";
@@ -1134,6 +1215,53 @@ fun load_bindings () {
 	}
 }
 
+fun load_history_level (const vector<string> &v) {
+	if (v.size () != 6)
+		return;
+	// Not checking the hostname and parent PID right now since we can't merge
+	g.levels.push_back ({stoi (v.at (4)), stoi (v.at (5)), v.at (3), v.at (6)});
+}
+
+fun load_config () {
+	auto config = xdg_config_find ("config");
+	if (!config)
+		return;
+
+	vector<string> tokens;
+	while (parse_line (*config, tokens)) {
+		if (tokens.empty ())
+			continue;
+
+		if      (tokens.front () == "full-view")
+			g.full_view = tokens.size () > 1 && tokens.at (1) == "1";
+		else if (tokens.front () == "gravity")
+			g.gravity   = tokens.size () > 1 && tokens.at (1) == "1";
+		else if (tokens.front () == "history")
+			load_history_level (tokens);
+	}
+}
+
+fun save_config () {
+	auto config = xdg_config_write ("config");
+	if (!config)
+		return;
+
+	write_line (*config, {"full-view", g.full_view ? "1" : "0"});
+	write_line (*config, {"gravity",   g.gravity   ? "1" : "0"});
+
+	char hostname[256];
+	if (gethostname (hostname, sizeof hostname))
+		*hostname = 0;
+
+	auto ppid = std::to_string (getppid ());
+	for (auto i = g.levels.begin (); i != g.levels.end (); i++)
+		write_line (*config, {"history", hostname, ppid, i->path,
+			to_string (i->offset), to_string (i->cursor), i->filename});
+	write_line (*config, {"history", hostname, ppid, g.cwd,
+		to_string (g.offset), to_string (g.cursor),
+		g.entries[g.cursor].filename});
+}
+
 int main (int argc, char *argv[]) {
 	(void) argc;
 	(void) argv;
@@ -1159,6 +1287,7 @@ int main (int argc, char *argv[]) {
 
 	locale::global (locale (""));
 	load_bindings ();
+	load_config ();
 
 	if (!initscr () || cbreak () == ERR || noecho () == ERR || nonl () == ERR) {
 		cerr << "cannot initialize screen" << endl;
@@ -1168,6 +1297,7 @@ int main (int argc, char *argv[]) {
 	load_colors ();
 	reload ();
 	g.start_dir = g.cwd;
+	pop_levels ();
 	update ();
 
 	// Invoking keypad() earlier would make ncurses flush its output buffer,
@@ -1179,9 +1309,15 @@ int main (int argc, char *argv[]) {
 	}
 
 	wint_t c;
-	while (!read_key (c) || handle (c))
+	while (!read_key (c) || handle (c)) {
 		inotify_check ();
+		if (g.message_ttl && !--g.message_ttl) {
+			g.message.clear ();
+			update ();
+		}
+	}
 	endwin ();
+	save_config ();
 
 	// Presumably it is going to end up as an argument, so quote it
 	if (!g.chosen.empty ())