From: Davin McCall <davmac@davmac.org>
Date: Fri, 1 Jan 2016 02:16:00 +0000 (+0000)
Subject: Add "run-on-console" service option, to specify that a service
X-Git-Tag: v0.01~75
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=41b55b06ee54123e6c5a4fbc997ec0766d9c441c;p=oweals%2Fdinit.git

Add "run-on-console" service option, to specify that a service
runs on the console.

Only one service can be running on the console at a time, so
there is a queue to obtain the console.

Not 100% complete yet. Part of the functionality seems to have
crept in with previous commit though? git gremlins...
---

diff --git a/load_service.cc b/load_service.cc
index 8957f0e..a7f1fef 100644
--- a/load_service.cc
+++ b/load_service.cc
@@ -322,6 +322,10 @@ ServiceRecord * ServiceSet::loadServiceRecord(const char * name)
                     string sigtermsetting = read_setting_value(i, end);
                     onstart_flags.no_sigterm = (sigtermsetting == "yes" || sigtermsetting == "true");
                 }
+                else if (setting == "runs-on-console") {
+                    string runconsolesetting = read_setting_value(i, end);
+                    onstart_flags.runs_on_console = (runconsolesetting == "yes" || runconsolesetting == "true");
+                }
                 else {
                     throw ServiceDescriptionExc(name, "Unknown setting: " + setting);
                 }
diff --git a/service.h b/service.h
index ae05e26..ea83149 100644
--- a/service.h
+++ b/service.h
@@ -41,8 +41,10 @@ struct OnstartFlags {
     
     // Not actually "onstart" commands:
     bool no_sigterm : 1;  // do not send SIGTERM
+    bool runs_on_console : 1;  // run "in the foreground"
     
-    OnstartFlags() noexcept : release_console(false), rw_ready(false), no_sigterm(false)
+    OnstartFlags() noexcept : release_console(false), rw_ready(false),
+            no_sigterm(false), runs_on_console(false)
     {
     }
 };
@@ -186,6 +188,9 @@ class ServiceRecord
     
     ServiceSet *service_set; // the set this service belongs to
     
+    // Next service (after this one) in the queue for the console:
+    ServiceRecord *next_for_console;
+    
     // Process services:
     bool force_stop; // true if the service must actually stop. This is the
                      // case if for example the process dies; the service,
@@ -222,7 +227,7 @@ class ServiceRecord
     
     // For process services, start the process, return true on success
     bool start_ps_process() noexcept;
-    bool start_ps_process(const std::vector<const char *> &args) noexcept;
+    bool start_ps_process(const std::vector<const char *> &args, bool on_console) noexcept;
 
     // Callback from libev when a child process dies
     static void process_child_callback(struct ev_loop *loop, struct ev_child *w,
@@ -231,7 +236,7 @@ class ServiceRecord
     // A dependency has reached STARTED state
     void dependencyStarted() noexcept;
     
-    void allDepsStarted() noexcept;
+    void allDepsStarted(bool haveConsole = false) noexcept;
     
     // Check whether dependencies have started, and optionally ask them to start
     bool startCheckDependencies(bool do_start) noexcept;
@@ -247,13 +252,21 @@ class ServiceRecord
     
     void forceStop() noexcept; // force-stop this service and all dependents
     
-    void notifyListeners(ServiceEvent event)
+    void notifyListeners(ServiceEvent event) noexcept
     {
         for (auto l : listeners) {
             l->serviceEvent(this, event);
         }
     }
     
+    // Queue to run on the console. 'acquiredConsole()' will be called when the console is available.
+    void queueForConsole() noexcept;
+    
+    // Console is available.
+    void acquiredConsole() noexcept;
+    
+    // Release console (console must be currently held by this service)
+    void releaseConsole() noexcept;
     
     public:
 
@@ -374,6 +387,8 @@ class ServiceSet
     
     ShutdownType shutdown_type = ShutdownType::CONTINUE;  // Shutdown type, if stopping
     
+    ServiceRecord * console_queue_tail = nullptr; // last record in console queue
+    
     // Private methods
         
     // Load a service description, and dependencies, if there is no existing
@@ -421,6 +436,14 @@ class ServiceSet
     // transition to the 'stopped' state.
     void stopService(const std::string &name) noexcept;
     
+    // Set the console queue tail (returns previous tail)
+    ServiceRecord * consoleQueueTail(ServiceRecord * newTail) noexcept
+    {
+        auto prev_tail = console_queue_tail;
+        console_queue_tail = newTail;
+        return prev_tail;
+    }
+    
     // Notification from service that it is active (state != STOPPED)
     // Only to be called on the transition from inactive to active.
     void service_active(ServiceRecord *) noexcept;