lua: avoid tarantool console quit if sigint signal sending

changelogs/unreleased/gh-2717-noquit-on-sigint.md

@@ -0,0 +1,4 @@
+## bugfix/lua
+
+* Fixed the behavior of tarantool console on SIGINT. Now Ctrl+C discards
+  the current input and prints the new prompt (gh-2717).

src/box/lua/console.c

@@ -41,6 +41,7 @@
 #include "iostream.h"
 #include "lua/msgpack.h"
 #include "lua-yaml/lyaml.h"
+#include "main.h"
 #include "serialize_lua.h"
 #include <lua.h>
 #include <lauxlib.h>
@@ -226,13 +227,37 @@ console_push_line(char *line)
 	free(line);
 }
 
+static bool sigint_called;
+/*
+ * The pointer to interactive fiber is needed to wake it up
+ * when SIGINT handler is called.
+ */
+static struct fiber *interactive_fb;
+
+/*
+ * The sigint callback for console mode.
+ */
+static void
+console_sigint_handler(ev_loop *loop, struct ev_signal *w, int revents)
+{
+	(void)loop;
+	(void)w;
+	(void)revents;
+
+	sigint_called = true;
+	fiber_wakeup(interactive_fb);
+}
+
 /* implements readline() Lua API */
 static int
 lbox_console_readline(struct lua_State *L)
 {
 	const char *prompt = NULL;
 	int top;
 	int completion = 0;
+	interactive_fb = fiber();
+	sigint_cb_t old_cb = set_sigint_cb(console_sigint_handler);
+	sigint_called = false;
 
 	if (lua_gettop(L) > 0) {
 		switch (lua_type(L, 1)) {
@@ -284,12 +309,35 @@ lbox_console_readline(struct lua_State *L)
 	while (top == lua_gettop(L)) {
 		while (coio_wait(STDIN_FILENO, COIO_READ,
 				 TIMEOUT_INFINITY) == 0) {
+			if (sigint_called) {
+				const char *line_end = "^C\n";
+				ssize_t rc = write(STDOUT_FILENO, line_end,
+						   strlen(line_end));
+				(void)rc;
+				/*
+				 * Discard current input and disable search
+				 * mode.
+				 */
+				RL_UNSETSTATE(RL_STATE_ISEARCH |
+					      RL_STATE_NSEARCH |
+					      RL_STATE_SEARCH);
+				rl_on_new_line();
+				rl_replace_line("", 0);
+				lua_pushstring(L, "");
+
+				readline_L = NULL;
+				sigint_called = false;
+				set_sigint_cb(old_cb);
+				return 1;
+			}
 			/*
 			 * Make sure the user of interactive
 			 * console has not hanged us, otherwise
 			 * we might spin here forever eating
 			 * the whole cpu time.
 			 */
+			if (fiber_is_cancelled())
+				set_sigint_cb(old_cb);
 			luaL_testcancel(L);
 		}
 		rl_callback_read_char();
@@ -299,6 +347,7 @@ lbox_console_readline(struct lua_State *L)
 	/* Incidents happen. */
 #pragma GCC poison readline_L
 	rl_attempted_completion_function = NULL;
+	set_sigint_cb(old_cb);
 	luaL_testcancel(L);
 	return 1;
 }

src/main.cc

@@ -180,6 +180,20 @@ signal_cb(ev_loop *loop, struct ev_signal *w, int revents)
 	tarantool_exit(0);
 }
 
+/*
+ * Handle SIGINT like SIGTERM by default, but allow to overwrite the behavior.
+ * Used by console.
+ */
+static sigint_cb_t signal_sigint_cb = signal_cb;
+
+sigint_cb_t
+set_sigint_cb(sigint_cb_t new_sigint_cb)
+{
+	sigint_cb_t old_cb = signal_sigint_cb;
+	ev_set_cb(&ev_sigs[1], new_sigint_cb);
+	return old_cb;
+}
+
 static void
 signal_sigwinch_cb(ev_loop *loop, struct ev_signal *w, int revents)
 {
@@ -253,7 +267,7 @@ signal_init(void)
 	crash_signal_init();
 
 	ev_signal_init(&ev_sigs[0], sig_checkpoint, SIGUSR1);
-	ev_signal_init(&ev_sigs[1], signal_cb, SIGINT);
+	ev_signal_init(&ev_sigs[1], signal_sigint_cb, SIGINT);
 	ev_signal_init(&ev_sigs[2], signal_cb, SIGTERM);
 	ev_signal_init(&ev_sigs[3], signal_sigwinch_cb, SIGWINCH);
 	ev_signal_init(&ev_sigs[4], say_logrotate, SIGHUP);

src/main.h

@@ -45,6 +45,21 @@ tarantool_exit(int);
 void
 load_cfg(void);
 
+/* The type of sigint callback's pointer. */
+struct ev_loop;
+struct ev_signal;
+typedef void
+(*sigint_cb_t)(struct ev_loop *loop, struct ev_signal *w, int revents);
+
+/*
+ * This function is needed for setting the new sigint callback.
+ * Returns the pointer to the old callback function.
+ * The main scenario is to replace the current callback
+ * and having an opportunity to set the old one back.
+ */
+sigint_cb_t
+set_sigint_cb(sigint_cb_t new_sigint_cb);
+
 #if defined(__cplusplus)
 } /* extern "C" */
 #endif /* defined(__cplusplus) */

test/app-tap/gh-2717-no-quit-sigint.test.lua

@@ -0,0 +1,204 @@
+#!/usr/bin/env tarantool
+
+local tap = require('tap')
+local popen = require('popen')
+local process_timeout = require('process_timeout')
+local fio = require('fio')
+local clock = require('clock')
+local fiber = require('fiber')
+
+--
+-- gh-2717: tarantool console quit on sigint.
+--
+local file_read_timeout = 60.0
+local file_read_interval = 0.2
+local file_open_timeout = 60.0
+local prompt = 'tarantool> '
+
+local TARANTOOL_PATH = arg[-1]
+local test = tap.test('gh-2717-no-quit-sigint')
+
+test:plan(6)
+local cmd = 'ERRINJ_STDIN_ISATTY=1 ' .. TARANTOOL_PATH .. ' -i 2>&1'
+local ph = popen.new({cmd}, {
+    shell = true,
+    setsid = true,
+    group_signal = true,
+    stdout = popen.opts.PIPE,
+    stderr = popen.opts.DEVNULL,
+    stdin = popen.opts.PIPE,
+})
+assert(ph, 'process is not up')
+
+local start_time = clock.monotonic()
+local time_quota = 10.0
+
+local output = ''
+while output:find(prompt) == nil
+        and clock.monotonic() - start_time < time_quota do
+    output = output .. ph:read({timeout = 1.0})
+end
+assert(clock.monotonic() - start_time < time_quota, 'time_quota is violated')
+ph:signal(popen.signal.SIGINT)
+
+while output:find(prompt .. '^C\n---\n...\n\n' .. prompt) == nil and
+        clock.monotonic() - start_time < time_quota do
+    local data = ph:read({timeout = 1.0})
+    if data ~= nil then
+        output = output .. data
+    end
+end
+assert(clock.monotonic() - start_time < time_quota, 'time_quota is violated')
+
+test:unlike(ph:info().status.state, popen.state.EXITED,
+            'SIGINT doesn\'t kill tarantool in interactive mode')
+test:like(output, prompt .. '^C\n---\n...\n\n' .. prompt,
+          'Ctrl+C discards the input and calls the new prompt')
+
+ph:shutdown({stdin = true})
+ph:close()
+
+--
+-- gh-2717: testing daemonized tarantool on signaling INT
+-- and nested console output.
+--
+local log_file = fio.abspath('tarantool.log')
+local pid_file = fio.abspath('tarantool.pid')
+local xlog_file = fio.abspath('00000000000000000000.xlog')
+local snap_file = fio.abspath('00000000000000000000.snap')
+local sock = fio.abspath('tarantool.soc')
+
+local user_grant = ' box.schema.user.grant(\'guest\', \'super\')'
+local arg = ' -e \"box.cfg{pid_file=\''
+            .. pid_file .. '\', log=\'' .. log_file .. '\', listen=\'unix/:'
+            .. sock .. '\'}' .. user_grant .. '\"'
+
+start_time = clock.monotonic()
+time_quota = 10.0
+
+os.remove(log_file)
+os.remove(pid_file)
+os.remove(xlog_file)
+os.remove(snap_file)
+
+local ph_server = popen.shell(TARANTOOL_PATH .. arg, 'r')
+
+local f = process_timeout.open_with_timeout(log_file, file_open_timeout)
+assert(f, 'error while opening ' .. log_file)
+
+cmd = 'ERRINJ_STDIN_ISATTY=1 ' .. TARANTOOL_PATH .. ' -i 2>&1'
+local ph_client = popen.new({cmd}, {
+    shell = true,
+    setsid = true,
+    group_signal = true,
+    stdout = popen.opts.PIPE,
+    stderr = popen.opts.DEVNULL,
+    stdin = popen.opts.PIPE,
+})
+assert(ph_client, 'the nested console is not up')
+
+ph_client:write('require("console").connect(\'unix/:' .. sock .. '\')\n')
+
+local client_data = ''
+while string.endswith(client_data, 'unix/:' .. sock .. '>') == nil
+        and clock.monotonic() - start_time < time_quota do
+    local cur_data = ph_client:read({timeout = 3.0})
+    if cur_data ~= nil and cur_data ~= '' then
+        client_data = client_data .. cur_data
+    end
+end
+assert(clock.monotonic() - start_time < time_quota, 'time_quota is violated')
+
+start_time = clock.monotonic()
+ph_client:signal(popen.signal.SIGINT)
+test:unlike(ph_client:info().status.state, popen.state.EXITED,
+            'SIGINT doesn\'t kill nested tarantool in interactive mode')
+while string.endswith(client_data, 'C\n---\n...\n\nunix/:' .. sock .. '>') == nil
+        and clock.monotonic() - start_time < time_quota do
+    local cur_data = ph_client:read({timeout = 3.0})
+    if cur_data ~= nil and cur_data ~= '' then
+        client_data = client_data .. cur_data
+    end
+end
+assert(clock.monotonic() - start_time < time_quota, 'time_quota is violated')
+
+ph_server:signal(popen.signal.SIGINT)
+
+local status = ph_server:wait(nil, popen.signal.SIGINT)
+test:unlike(status.state, popen.state.ALIVE,
+            'SIGINT terminates tarantool in daemon mode')
+
+start_time = clock.monotonic()
+local data = ''
+while data:match('got signal 2') == nil
+        and clock.monotonic() - start_time < time_quota do
+    data = data .. process_timeout.read_with_timeout(f,
+            file_read_timeout,
+            file_read_interval)
+end
+assert(data:match('got signal 2'), 'there is no one note about SIGINT')
+assert(clock.monotonic() - start_time < time_quota, 'time_quota is violated')
+
+f:close()
+ph_server:close()
+ph_client:close()
+os.remove(log_file)
+os.remove(pid_file)
+os.remove(xlog_file)
+os.remove(snap_file)
+
+--
+-- Testing case when the client and instance are called in the same console.
+--
+cmd = 'ERRINJ_STDIN_ISATTY=1 ' .. TARANTOOL_PATH .. ' -i 2>&1'
+ph = popen.new({cmd}, {
+    shell = true,
+    setsid = true,
+    group_signal = true,
+    stdout = popen.opts.PIPE,
+    stderr = popen.opts.DEVNULL,
+    stdin = popen.opts.PIPE,
+})
+assert(ph, 'process is not up')
+
+start_time = clock.monotonic()
+time_quota = 10.0
+
+output = ''
+while output:find(prompt) == nil
+        and clock.monotonic() - start_time < time_quota do
+    data = ph:read({timeout = 1.0})
+    if data ~= nil then
+        output = output .. data
+    end
+end
+assert(clock.monotonic() - start_time < time_quota, 'time_quota is violated')
+
+prompt = 'unix/:' .. sock .. '> '
+ph:write('_ = require(\'console\').listen(\'' .. sock .. '\')\n',
+         {timeout = 1.0})
+ph:write('_ = require(\'console\').connect(\'' .. sock .. '\')\n',
+         {timeout = 1.0})
+
+fiber.sleep(0.2)
+ph:signal(popen.signal.SIGINT)
+
+start_time = clock.monotonic()
+while string.endswith(output, prompt .. '^C\n---\n...\n\n' .. prompt) == false
+        and clock.monotonic() - start_time < time_quota do
+    local data = ph:read({timeout = 1.0})
+    if data ~= nil then
+        output = output .. data
+    end
+end
+assert(clock.monotonic() - start_time < time_quota, 'time_quota is violated')
+
+test:ok(string.endswith(output, prompt .. '^C\n---\n...\n\n' .. prompt),
+        'Ctrl+C discards the input and calls the new prompt')
+test:unlike(ph:info().status.state, popen.state.EXITED,
+            'SIGINT doesn\'t kill tarantool in interactive mode')
+
+ph:shutdown({stdin = true})
+ph:close()
+
+os.exit(test:check() and 0 or 1)

test/app-tap/suite.ini

@@ -4,7 +4,7 @@ description = application server tests (TAP)
 lua_libs = lua/require_mod.lua lua/serializer_test.lua lua/process_timeout.lua
 is_parallel = True
 use_unix_sockets_iproto = True
-release_disabled = gh-5040-inter-mode-isatty-via-errinj.test.lua
+release_disabled = gh-5040-inter-mode-isatty-via-errinj.test.lua gh-2717-no-quit-sigint.test.lua
 fragile = {
     "retries": 10,
     "tests": {