From b9e0da92007a733357ce7a2893168b31a9665a9f Mon Sep 17 00:00:00 2001
From: Hisham Muhammad <hisham@gobolinux.org>
Date: Thu, 5 Apr 2018 19:31:18 -0300
Subject: [PATCH] Collapse current subtree pressing Backspace

---
 Action.c      | 24 ++++++++++++++++++++++++
 Process.c     |  2 ++
 Process.h     |  2 ++
 ProcessList.c |  2 +-
 4 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/Action.c b/Action.c
index dc830b57..f7d7d4da 100644
--- a/Action.c
+++ b/Action.c
@@ -155,6 +155,21 @@ static bool expandCollapse(Panel* panel) {
    return true;
 }
 
+static bool collapseIntoParent(Panel* panel) {
+   Process* p = (Process*) Panel_getSelected(panel);
+   if (!p) return false;
+   pid_t ppid = Process_getParentPid(p);
+   for (int i = 0; i < Panel_size(panel); i++) {
+      Process* q = (Process*) Panel_get(panel, i);
+      if (q->pid == ppid) {
+         q->showChildren = false;
+         Panel_setSelected(panel, i);
+         return true;
+      }
+   }
+   return false;
+}
+
 Htop_Reaction Action_setSortKey(Settings* settings, ProcessField sortKey) {
    ScreenSettings* ss = settings->ss;
    ss->sortKey = sortKey;
@@ -264,6 +279,14 @@ static Htop_Reaction actionExpandOrCollapse(State* st) {
    return changed ? HTOP_RECALCULATE : HTOP_OK;
 }
 
+static Htop_Reaction actionCollapseIntoParent(State* st) {
+   if (!st->settings->treeView) {
+      return HTOP_OK;
+   }
+   bool changed = collapseIntoParent(st->panel);
+   return changed ? HTOP_RECALCULATE : HTOP_OK;
+}
+
 static Htop_Reaction actionExpandCollapseOrSortColumn(State* st) {
    return st->settings->ss->treeView ? actionExpandOrCollapse(st) : actionSetSortColumn(st);
 }
@@ -570,6 +593,7 @@ void Action_setBindings(Htop_Action* keys) {
    keys['+'] = actionExpandOrCollapse;
    keys['='] = actionExpandOrCollapse;
    keys['-'] = actionExpandOrCollapse;
+   keys['\177'] = actionCollapseIntoParent;
    keys['u'] = actionFilterByUser;
    keys['F'] = Action_follow;
    keys['S'] = actionSetup;
diff --git a/Process.c b/Process.c
index 0a184b70..28c53dbc 100644
--- a/Process.c
+++ b/Process.c
@@ -179,6 +179,8 @@ typedef struct ProcessClass_ {
 
 #define As_Process(this_)              ((ProcessClass*)((this_)->super.klass))
 
+#define Process_getParentPid(process_)    (process_->tgid == process_->pid ? process_->ppid : process_->tgid)
+
 #define Process_isChildOf(process_, pid_) (process_->tgid == pid_ || (process_->tgid == process_->pid && process_->ppid == pid_))
 
 #define Process_sortState(state) ((state) == 'I' ? 0x100 : (state))
diff --git a/Process.h b/Process.h
index 3ff67d4c..b3b5e9e0 100644
--- a/Process.h
+++ b/Process.h
@@ -157,6 +157,8 @@ typedef struct ProcessClass_ {
 
 #define As_Process(this_)              ((ProcessClass*)((this_)->super.klass))
 
+#define Process_getParentPid(process_)    (process_->tgid == process_->pid ? process_->ppid : process_->tgid)
+
 #define Process_isChildOf(process_, pid_) (process_->tgid == pid_ || (process_->tgid == process_->pid && process_->ppid == pid_))
 
 #define Process_sortState(state) ((state) == 'I' ? 0x100 : (state))
diff --git a/ProcessList.c b/ProcessList.c
index 5b6a98f3..3d65bf4b 100644
--- a/ProcessList.c
+++ b/ProcessList.c
@@ -229,7 +229,7 @@ void ProcessList_sort(ProcessList* this) {
                ProcessList_buildTree(this, process->pid, 0, 0, direction, false);
                break;
             }
-            pid_t ppid = process->tgid == process->pid ? process->ppid : process->tgid;
+            pid_t ppid = Process_getParentPid(process);
             // Bisect the process vector to find parent
             int l = 0, r = size;
             // If PID corresponds with PPID (e.g. "kernel_task" (PID:0, PPID:0)