feat(editor): 'autowriteall' on SIGHUP/SIGQUIT #32843

Problem:
Upon receiving a deadly signal, Nvim doesn't write buffers even if
the option 'autowriteall' is set.

Solution:
Write to all writable buffers upon SIGHUP or SIGQUIT (but not
SIGTERM), if the option 'autowriteall' is set.

Co-authored-by: Justin M. Keyes <justinkz@gmail.com>

3 files changed, 79 insertions, 8 deletions

diff --git a/runtime/doc/news.txt b/runtime/doc/news.txt
index 2644bb24b2..c8fa343e46 100644
--- a/runtime/doc/news.txt
+++ b/runtime/doc/news.txt
@@ -134,6 +134,7 @@ OPTIONS
 
 • 'completefuzzycollect' enables fuzzy collection of candidates for (some)
   |ins-completion| modes.
+• 'autowriteall' write all buffers upon receiving `SIGHUP`, `SIGQUIT` or `SIGTSTP`.
 
 PERFORMANCE
 
diff --git a/src/nvim/os/signal.c b/src/nvim/os/signal.c
index 11f99d0a0f..55efce0337 100644
--- a/src/nvim/os/signal.c
+++ b/src/nvim/os/signal.c
@@ -12,16 +12,18 @@
 #include "nvim/eval.h"
 #include "nvim/event/defs.h"
 #include "nvim/event/signal.h"
+#include "nvim/ex_cmds2.h"
 #include "nvim/globals.h"
 #include "nvim/log.h"
 #include "nvim/main.h"
+#include "nvim/option_vars.h"
 #include "nvim/os/signal.h"
 
 #ifdef SIGPWR
 # include "nvim/memline.h"
 #endif
 
-static SignalWatcher spipe, shup, squit, sterm, susr1, swinch;
+static SignalWatcher spipe, shup, squit, sterm, susr1, swinch, ststp;
 #ifdef SIGPWR
 static SignalWatcher spwr;
 #endif
@@ -48,6 +50,7 @@ void signal_init(void)
   signal_watcher_init(&main_loop, &shup, NULL);
   signal_watcher_init(&main_loop, &squit, NULL);
   signal_watcher_init(&main_loop, &sterm, NULL);
+  signal_watcher_init(&main_loop, &ststp, NULL);
 #ifdef SIGPWR
   signal_watcher_init(&main_loop, &spwr, NULL);
 #endif
@@ -67,6 +70,7 @@ void signal_teardown(void)
   signal_watcher_close(&shup, NULL);
   signal_watcher_close(&squit, NULL);
   signal_watcher_close(&sterm, NULL);
+  signal_watcher_close(&ststp, NULL);
 #ifdef SIGPWR
   signal_watcher_close(&spwr, NULL);
 #endif
@@ -88,6 +92,9 @@ void signal_start(void)
   signal_watcher_start(&squit, on_signal, SIGQUIT);
 #endif
   signal_watcher_start(&sterm, on_signal, SIGTERM);
+#ifdef SIGTSTP
+  signal_watcher_start(&ststp, on_signal, SIGTSTP);
+#endif
 #ifdef SIGPWR
   signal_watcher_start(&spwr, on_signal, SIGPWR);
 #endif
@@ -109,6 +116,7 @@ void signal_stop(void)
   signal_watcher_stop(&squit);
 #endif
   signal_watcher_stop(&sterm);
+  signal_watcher_stop(&ststp);
 #ifdef SIGPWR
   signal_watcher_stop(&spwr);
 #endif
@@ -143,6 +151,10 @@ static char *signal_name(int signum)
 #endif
   case SIGTERM:
     return "SIGTERM";
+#ifdef SIGTSTP
+  case SIGTSTP:
+    return "SIGTSTP";
+#endif
 #ifdef SIGQUIT
   case SIGQUIT:
     return "SIGQUIT";
@@ -177,6 +189,10 @@ static void deadly_signal(int signum)
 
   snprintf(IObuff, IOSIZE, "Nvim: Caught deadly signal '%s'\n", signal_name(signum));
 
+  if (p_awa && signum != SIGTERM) {
+    autowrite_all();
+  }
+
   // Preserve files and exit.
   preserve_exit(IObuff);
 }
@@ -197,6 +213,9 @@ static void on_signal(SignalWatcher *handle, int signum, void *data)
     break;
 #endif
   case SIGTERM:
+#ifdef SIGTSTP
+  case SIGTSTP:
+#endif
 #ifdef SIGQUIT
   case SIGQUIT:
 #endif
diff --git a/test/functional/autocmd/signal_spec.lua b/test/functional/autocmd/signal_spec.lua
index 4416afb3ba..03e991f21c 100644
--- a/test/functional/autocmd/signal_spec.lua
+++ b/test/functional/autocmd/signal_spec.lua
@@ -8,39 +8,90 @@ local fn = n.fn
 local next_msg = n.next_msg
 local is_os = t.is_os
 local skip = t.skip
+local read_file = t.read_file
+local feed = n.feed
+local retry = t.retry
 
 if skip(is_os('win'), 'Only applies to POSIX systems') then
   return
 end
 
-local function posix_kill(signame, pid)
-  os.execute('kill -s ' .. signame .. ' -- ' .. pid .. ' >/dev/null')
-end
+describe("'autowriteall' on signal exit", function()
+  before_each(clear)
+
+  local function test_deadly_sig(signame, awa, should_write)
+    local testfile = 'Xtest_SIG' .. signame .. (awa and '_awa' or '_noawa')
+    local teststr = 'Testaaaaaaa'
+    finally(function()
+      os.remove(testfile)
+    end)
+
+    if awa then
+      command('set autowriteall')
+    end
+
+    command('edit ' .. testfile)
+    feed('i' .. teststr)
+    vim.uv.kill(fn.getpid(), signame)
+
+    retry(nil, 5000, function()
+      eq((should_write and (teststr .. '\n') or nil), read_file(testfile))
+    end)
+  end
+
+  it('dont write if SIGTERM & awa on', function()
+    test_deadly_sig('sigterm', true, false)
+  end)
+  it('dont write if SIGTERM & awa off', function()
+    test_deadly_sig('sigterm', false, false)
+  end)
+
+  it('write if SIGHUP & awa on', function()
+    test_deadly_sig('sighup', true, true)
+  end)
+  it('dont write if SIGHUP & awa off', function()
+    test_deadly_sig('sighup', false, false)
+  end)
+
+  it('write if SIGTSTP & awa on', function()
+    test_deadly_sig('sigtstp', true, true)
+  end)
+  it('dont write if SIGTSTP & awa off', function()
+    test_deadly_sig('sigtstp', false, false)
+  end)
+
+  it('write if SIGQUIT & awa on', function()
+    test_deadly_sig('sigquit', true, true)
+  end)
+  it('dont write if SIGQUIT & awa off', function()
+    test_deadly_sig('sigquit', false, false)
+  end)
+end)
 
 describe('autocmd Signal', function()
   before_each(clear)
 
   it('matches *', function()
     command('autocmd Signal * call rpcnotify(1, "foo")')
-    posix_kill('USR1', fn.getpid())
+    vim.uv.kill(fn.getpid(), 'sigusr1')
     eq({ 'notification', 'foo', {} }, next_msg())
   end)
 
   it('matches SIGUSR1', function()
     command('autocmd Signal SIGUSR1 call rpcnotify(1, "foo")')
-    posix_kill('USR1', fn.getpid())
+    vim.uv.kill(fn.getpid(), 'sigusr1')
     eq({ 'notification', 'foo', {} }, next_msg())
   end)
 
   it('matches SIGWINCH', function()
     command('autocmd Signal SIGWINCH call rpcnotify(1, "foo")')
-    posix_kill('WINCH', fn.getpid())
+    vim.uv.kill(fn.getpid(), 'sigwinch')
     eq({ 'notification', 'foo', {} }, next_msg())
   end)
 
   it('does not match unknown patterns', function()
     command('autocmd Signal SIGUSR2 call rpcnotify(1, "foo")')
-    posix_kill('USR1', fn.getpid())
+    vim.uv.kill(fn.getpid(), 'sigusr2')
     eq(nil, next_msg(500))
   end)
 end)