>From 150c30aec340d6ce00afa1251e6962c012449407 Mon Sep 17 00:00:00 2001
From: Assaf Gordon <address@hidden>
Date: Mon, 25 Feb 2019 18:03:19 -0700
Subject: [PATCH 3/3] env: add --list-blocked-signals/--list-signal-actions
 options

Example:

  $ ( trap '' PIPE && env --list-signal-actions )
  PIPE     (13): ignore

* NEWS: Mention new options.
* doc/coreutils.texi (env invocation): Mention new options.
* src/env.c (longopts,usage): Add new options.
(list_signal_actions, list_blocked_signals): New functions.
(main): Handle new options.
---
 NEWS               |  3 +++
 doc/coreutils.texi |  8 ++++++
 src/env.c          | 73 +++++++++++++++++++++++++++++++++++++++++++++++++++++-
 3 files changed, 83 insertions(+), 1 deletion(-)

diff --git a/NEWS b/NEWS
index cb8aa107f..3cef6066e 100644
--- a/NEWS
+++ b/NEWS
@@ -87,6 +87,9 @@ GNU coreutils NEWS                                    -*- outline -*-
   env now supports '--{block,unblock,setmask}-singal[=SIG]' to block/unblock
   signal delivery before executing a program.
 
+  env now supports '--list-signal-actions' and '--list-blocked-signals'
+  options.
+
 ** New commands
 
   basenc is added to complement existing base64,base32 commands,
diff --git a/doc/coreutils.texi b/doc/coreutils.texi
index 8f5212a72..b63161803 100644
--- a/doc/coreutils.texi
+++ b/doc/coreutils.texi
@@ -17309,6 +17309,14 @@ Unblock signal @var{sig}.
 Set list of blocked signals to @var{sig}. All other signals will be unblocked.
 
 
address@hidden --list-signal-actions
+List non-default actions for all signals and exit.
+If all signals are set to their default action, nothing is printed.
+
address@hidden --list-blocked-signals
+List blocked (masked) signals and exit.
+If no signals are blocked, nothing is printed.
+
 
 @item -p
 Equivalent to @option{--default-signal=PIPE} - sets SIGPIPE to its default
diff --git a/src/env.c b/src/env.c
index 4cae7d47f..43856200f 100644
--- a/src/env.c
+++ b/src/env.c
@@ -78,7 +78,9 @@ enum
   IGNORE_SIGNAL_OPTION,
   BLOCK_SIGNAL_OPTION,
   UNBLOCK_SIGNAL_OPTION,
-  SETMASK_SIGNAL_OPTION
+  SETMASK_SIGNAL_OPTION,
+  LIST_SIGNAL_ACTIONS_OPTION,
+  LIST_BLOCKED_SIGNALS_OPTION,
 };
 
 static struct option const longopts[] =
@@ -89,9 +91,11 @@ static struct option const longopts[] =
   {"chdir", required_argument, NULL, 'C'},
   {"default-signal", optional_argument, NULL, DEFAULT_SIGNAL_OPTION},
   {"ignore-signal",  optional_argument, NULL, IGNORE_SIGNAL_OPTION},
+  {"list-signal-actions", no_argument, NULL,  LIST_SIGNAL_ACTIONS_OPTION},
   {"block-signal",   optional_argument, NULL, BLOCK_SIGNAL_OPTION},
   {"unblock-signal", optional_argument, NULL, UNBLOCK_SIGNAL_OPTION},
   {"setmask-signal", optional_argument, NULL, SETMASK_SIGNAL_OPTION},
+  {"list-blocked-signals", no_argument, NULL, LIST_BLOCKED_SIGNALS_OPTION},
   {"debug", no_argument, NULL, 'v'},
   {"split-string", required_argument, NULL, 'S'},
   {GETOPT_HELP_OPTION_DECL},
@@ -143,6 +147,15 @@ Set each NAME to VALUE in the environment and run COMMAND.\n\
                         used to pass multiple arguments on shebang lines\n\
 "), stdout);
       fputs (_("\
+      --list-signal-actions   list non-default actions for signals and exit.\n\
+                              if all signals use their default actions,\n\
+                              nothing is printed.\n\
+"), stdout);
+      fputs (_("\
+      --list-blocked-signals  list blocked (masked) signals and exit.\n\
+                              if no signals are blocked, nothing is printed.\n\
+"), stdout);
+      fputs (_("\
   -p                   same as --default-signal=PIPE\n\
 "), stdout);
       fputs (_("\
@@ -670,6 +683,35 @@ reset_signal_handlers (void)
 }
 
 static void
+list_signal_actions (void)
+{
+  char signame[SIG2STR_MAX];
+  const char* action;
+
+  for (int i = 1; i < SIGNUM_BOUND; i++)
+    {
+      struct sigaction act;
+      if (sigaction (i, NULL, &act))
+        continue;
+
+      if (act.sa_flags & SA_SIGINFO)
+        action = "sig-action";
+      else if (act.sa_handler == SIG_DFL)
+        continue; /* no need to print defaults.  */
+      else if (act.sa_handler == SIG_IGN)
+        action = "ignore";
+      else
+        action = "sig-handler";
+
+      sig2str (i, signame);
+      printf ("%-10s (%2d): %s\n", signame, i, action);
+    }
+
+  exit (EXIT_SUCCESS);
+}
+
+
+static void
 parse_block_signal_params (const char* optarg, bool block)
 {
   char signame[SIG2STR_MAX];
@@ -747,6 +789,29 @@ set_signal_proc_mask (void)
     die (EXIT_CANCELED, errno, _("failed to set signal process mask"));
 }
 
+static void
+list_blocked_signals (void)
+{
+  sigset_t set;
+  char signame[SIG2STR_MAX];
+
+  sigemptyset (&set);
+  if (sigprocmask (0, NULL, &set))
+    die (EXIT_CANCELED, errno, _("failed to get signal process mask"));
+
+  for (int i = 1; i < SIGNUM_BOUND; i++)
+    {
+      if (!sigismember (&set, i))
+        continue;
+
+      sig2str (i, signame);
+      printf ("%-10s (%2d)\n", signame, i);
+    }
+
+  exit (EXIT_SUCCESS);
+}
+
+
 int
 main (int argc, char **argv)
 {
@@ -790,6 +855,9 @@ main (int argc, char **argv)
         case IGNORE_SIGNAL_OPTION:
           parse_signal_action_params (optarg, false);
           break;
+        case LIST_SIGNAL_ACTIONS_OPTION:
+          list_signal_actions ();
+          break;
         case BLOCK_SIGNAL_OPTION:
           parse_block_signal_params (optarg, true);
           break;
@@ -801,6 +869,9 @@ main (int argc, char **argv)
           sigemptyset (&block_signals);
           parse_block_signal_params (optarg, true);
           break;
+        case LIST_BLOCKED_SIGNALS_OPTION:
+          list_blocked_signals ();
+          break;
         case 'C':
           newdir = optarg;
           break;
-- 
2.11.0