Support dynamic screens with 'top-most' entities beyond processes

This implements our concept of 'dynamic screens' in htop, with a
first use-case of pcp-htop displaying things like top-filesystem
and top-cgroups under new screen tabs.  However the idea is more
general than use in pcp-htop and we've paved the way here for us
to collectively build mroe general tabular screens in core htop,
as well.

From the pcp-htop side of things, dynamic screens are configured
using text-based configuration files that define the mapping for
PCP metrics to columns (and metric instances to rows).  Metrics
are defined either directly (via metric names) or indirectly via
PCP derived metric specifications.  Value scaling and the units
displayed is automatic based on PCP metric units and data types.

This commit represents a collaborative effort of several months,
primarily between myself, Nathan and BenBE.

Signed-off-by: Sohaib Mohamed <sohaib.amhmd@gmail.com>
Signed-off-by: Nathan Scott <nathans@redhat.com>

1 files changed, 31 insertions, 1 deletions

diff --git a/pcp/Platform.c b/pcp/Platform.c
index 87a2ec1f..53336197 100644
--- a/pcp/Platform.c
+++ b/pcp/Platform.c
@@ -25,6 +25,7 @@ in the source distribution for its full text.
 #include "DiskIOMeter.h"
 #include "DynamicColumn.h"
 #include "DynamicMeter.h"
+#include "DynamicScreen.h"
 #include "FileDescriptorMeter.h"
 #include "HostnameMeter.h"
 #include "LoadAverageMeter.h"
@@ -46,6 +47,7 @@ in the source distribution for its full text.
 #include "linux/ZramStats.h"
 #include "pcp/PCPDynamicColumn.h"
 #include "pcp/PCPDynamicMeter.h"
+#include "pcp/PCPDynamicScreen.h"
 #include "pcp/PCPMachine.h"
 #include "pcp/PCPMetric.h"
 #include "pcp/PCPProcessList.h"
@@ -355,6 +357,7 @@ bool Platform_init(void) {
 
    pcp->columns.offset = PCP_METRIC_COUNT + pcp->meters.cursor;
    PCPDynamicColumns_init(&pcp->columns);
+   PCPDynamicScreens_init(&pcp->screens, &pcp->columns);
 
    sts = pmLookupName(pcp->totalMetrics, pcp->names, pcp->pmids);
    if (sts < 0) {
@@ -386,6 +389,7 @@ bool Platform_init(void) {
    PCPMetric_enable(PCP_UNAME_MACHINE, true);
    PCPMetric_enable(PCP_UNAME_DISTRO, true);
 
+   /* enable metrics for all dynamic columns (including those from dynamic screens) */
    for (size_t i = pcp->columns.offset; i < pcp->columns.offset + pcp->columns.count; i++)
       PCPMetric_enable(i, true);
 
@@ -417,6 +421,10 @@ void Platform_dynamicMetersDone(Hashtable* meters) {
    PCPDynamicMeters_done(meters);
 }
 
+void Platform_dynamicScreensDone(Hashtable* screens) {
+   PCPDynamicScreens_done(screens);
+}
+
 void Platform_done(void) {
    pmDestroyContext(pcp->context);
    if (pcp->result)
@@ -850,7 +858,7 @@ Hashtable* Platform_dynamicColumns(void) {
    return pcp->columns.table;
 }
 
-const char* Platform_dynamicColumnInit(unsigned int key) {
+const char* Platform_dynamicColumnName(unsigned int key) {
    PCPDynamicColumn* this = Hashtable_get(pcp->columns.table, key);
    if (this) {
       PCPMetric_enable(this->id, true);
@@ -871,3 +879,25 @@ bool Platform_dynamicColumnWriteField(const Process* proc, RichString* str, unsi
    }
    return false;
 }
+
+Hashtable* Platform_dynamicScreens(void) {
+   return pcp->screens.table;
+}
+
+void Platform_defaultDynamicScreens(Settings* settings) {
+   PCPDynamicScreen_appendScreens(&pcp->screens, settings);
+}
+
+void Platform_addDynamicScreen(ScreenSettings* ss) {
+   PCPDynamicScreen_addDynamicScreen(&pcp->screens, ss);
+}
+
+void Platform_addDynamicScreenAvailableColumns(Panel* availableColumns, const char* screen) {
+   Hashtable* screens = pcp->screens.table;
+   PCPDynamicScreens_addAvailableColumns(availableColumns, screens, screen);
+}
+
+void Platform_updateTables(Machine* host) {
+    PCPDynamicScreen_appendTables(&pcp->screens, host);
+    PCPDynamicColumns_setupWidths(&pcp->columns);
+}