From e83419d043e4f1e11f52d9a3360b0e5bdea71031 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>
Date: Wed, 26 Sep 2018 07:31:10 +0200
Subject: [PATCH] hib-res-generator: add "noresume"

This is an override parameter, to totally skip dehiberanation.
---
 TODO                                            |  5 ++---
 man/systemd-hibernate-resume-generator.xml      | 14 +++++++++++---
 .../hibernate-resume-generator.c                | 17 +++++++++++++++--
 3 files changed, 28 insertions(+), 8 deletions(-)

diff --git a/TODO b/TODO
index f848b9741e..59ea95746c 100644
--- a/TODO
+++ b/TODO
@@ -86,11 +86,10 @@ Features:
 
   1. add resume_offset support to the resume code (i.e. support swap files
      properly)
-  2. check of swap is on weird storage and refuse if so
+  2. check if swap is on weird storage and refuse if so
   3. add env-var based option to disable hibernation
   4. figure out what to do with swap-on-luks
-  5. add autodetection of hibernation images, and add "noresume" to disable
-     this
+  5. add autodetection of hibernation images
 
 * portables: introduce a new unit file directory /etc/systemd/system.attached/
   or so, where we attach portable services to
diff --git a/man/systemd-hibernate-resume-generator.xml b/man/systemd-hibernate-resume-generator.xml
index 86d45dc4af..8f0cc5d044 100644
--- a/man/systemd-hibernate-resume-generator.xml
+++ b/man/systemd-hibernate-resume-generator.xml
@@ -28,11 +28,13 @@
   <refsect1>
     <title>Description</title>
 
-    <para><filename>systemd-hibernate-resume-generator</filename> is a
-    generator that instantiates
+    <para><command>systemd-hibernate-resume-generator</command> is a
+    generator that initiates the procedure to resume the system from hibernation.
+    It instantiates the
     <citerefentry><refentrytitle>systemd-hibernate-resume@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
     unit according to the value of <option>resume=</option> parameter
-    specified on the kernel command line.</para>
+    specified on the kernel command line, which will instruct the kernel
+    to resume the system from the hibernation image on that device.</para>
   </refsect1>
 
   <refsect1>
@@ -54,6 +56,12 @@
         supported.</para></listitem>
       </varlistentry>
 
+      <varlistentry>
+        <term><varname>noresume</varname></term>
+
+        <listitem><para>Do not try to resume from hibernation. If this parameter is
+        present, <varname>resume=</varname> is ignored.</para></listitem>
+      </varlistentry>
     </variablelist>
   </refsect1>
 
diff --git a/src/hibernate-resume/hibernate-resume-generator.c b/src/hibernate-resume/hibernate-resume-generator.c
index 8ff44c3bb9..036493a389 100644
--- a/src/hibernate-resume/hibernate-resume-generator.c
+++ b/src/hibernate-resume/hibernate-resume-generator.c
@@ -15,6 +15,7 @@
 
 static const char *arg_dest = "/tmp";
 static char *arg_resume_device = NULL;
+static bool arg_noresume = false;
 
 static int parse_proc_cmdline_item(const char *key, const char *value, void *data) {
 
@@ -28,8 +29,15 @@ static int parse_proc_cmdline_item(const char *key, const char *value, void *dat
                 if (!s)
                         return log_oom();
 
-                free(arg_resume_device);
-                arg_resume_device = s;
+                free_and_replace(arg_resume_device, s);
+
+        } else if (streq(key, "noresume")) {
+                if (value) {
+                        log_warning("\"noresume\" kernel command line switch specified with an argument, ignoring.");
+                        return 0;
+                }
+
+                arg_noresume = true;
         }
 
         return 0;
@@ -85,6 +93,11 @@ int main(int argc, char *argv[]) {
         if (r < 0)
                 log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");
 
+        if (arg_noresume) {
+                log_notice("Found \"noresume\" on the kernel command line, quitting.");
+                return EXIT_SUCCESS;
+        }
+
         r = process_resume();
         free(arg_resume_device);