Add a new DynamicMeter class for runtime Meter extension

This commit is based on exploratory work by Sohaib Mohamed.
The end goal is two-fold - to support addition of Meters we
build via configuration files for both the PCP platform and
for scripts ( https://github.com/htop-dev/htop/issues/526 )

Here, we focus on generic code and the PCP support.  A new
class DynamicMeter is introduced - it uses the special case
'param' field handling that previously was used only by the
CPUMeter, such that every runtime-configured Meter is given
a unique identifier.  Unlike with the CPUMeter this is used
internally only.  When reading/writing to htoprc instead of
CPU(N) - where N is an integer param (CPU number) - we use
the string name for each meter.  For example, if we have a
configuration for a DynamicMeter for some Redis metrics, we
might read and write "Dynamic(redis)".  This identifier is
subsequently matched (back) up to the configuration file so
we're able to re-create arbitrary user configurations.

The PCP platform configuration file format is fairly simple.
We expand configs from several directories, including the
users homedir alongside htoprc (below htop/meters/) and also
/etc/pcp/htop/meters.  The format will be described via a
new pcp-htop(5) man page, but its basically ini-style and
each Meter has one or more metric expressions associated, as
well as specifications for labels, color and so on via a dot
separated notation for individual metrics within the Meter.

A few initial sample configuration files are provided below
./pcp/meters that give the general idea.  The PCP "derived"
metric specification - see pmRegisterDerived(3) - is used
as the syntax for specifying metrics in PCP DynamicMeters.

48 files changed, 1044 insertions, 68 deletions

diff --git a/AvailableMetersPanel.c b/AvailableMetersPanel.c
index 22f2c5ef..048c7175 100644
--- a/AvailableMetersPanel.c
+++ b/AvailableMetersPanel.c
@@ -12,6 +12,7 @@ in the source distribution for its full text.
 #include <stdlib.h>
 
 #include "CPUMeter.h"
+#include "DynamicMeter.h"
 #include "FunctionBar.h"
 #include "Header.h"
 #include "ListItem.h"
@@ -91,6 +92,49 @@ const PanelClass AvailableMetersPanel_class = {
    .eventHandler = AvailableMetersPanel_eventHandler
 };
 
+// Handle (&CPUMeter_class) entries in the AvailableMetersPanel
+static void AvailableMetersPanel_addCPUMeters(Panel* super, const MeterClass* type, const ProcessList* pl) {
+   if (pl->cpuCount > 1) {
+      Panel_add(super, (Object*) ListItem_new("CPU average", 0));
+      for (unsigned int i = 1; i <= pl->cpuCount; i++) {
+         char buffer[50];
+         xSnprintf(buffer, sizeof(buffer), "%s %d", type->uiName, Settings_cpuId(pl->settings, i - 1));
+         Panel_add(super, (Object*) ListItem_new(buffer, i));
+      }
+   } else {
+      Panel_add(super, (Object*) ListItem_new(type->uiName, 1));
+   }
+}
+
+typedef struct {
+   Panel* super;
+   unsigned int id;
+   unsigned int offset;
+} DynamicIterator;
+
+static void AvailableMetersPanel_addDynamicMeter(ATTR_UNUSED ht_key_t key, void* value, void* data) {
+   const DynamicMeter* meter = (const DynamicMeter*)value;
+   DynamicIterator* iter = (DynamicIterator*)data;
+   unsigned int identifier = (iter->offset << 16) | iter->id;
+   const char* label = meter->description ? meter->description : meter->caption;
+   if (!label) label = meter->name; /* last fallback to name, guaranteed set */
+   Panel_add(iter->super, (Object*) ListItem_new(label, identifier));
+   iter->id++;
+}
+
+// Handle (&DynamicMeter_class) entries in the AvailableMetersPanel
+static void AvailableMetersPanel_addDynamicMeters(Panel* super, const ProcessList *pl, unsigned int offset) {
+   DynamicIterator iter = { .super = super, .id = 1, .offset = offset };
+   assert(pl->dynamicMeters != NULL);
+   Hashtable_foreach(pl->dynamicMeters, AvailableMetersPanel_addDynamicMeter, &iter);
+}
+
+// Handle remaining Platform Meter entries in the AvailableMetersPanel
+static void AvailableMetersPanel_addPlatformMeter(Panel* super, const MeterClass* type, unsigned int offset) {
+   const char* label = type->description ? type->description : type->uiName;
+   Panel_add(super, (Object*) ListItem_new(label, offset << 16));
+}
+
 AvailableMetersPanel* AvailableMetersPanel_new(Settings* settings, Header* header, Panel* leftMeters, Panel* rightMeters, ScreenManager* scr, const ProcessList* pl) {
    AvailableMetersPanel* this = AllocThis(AvailableMetersPanel);
    Panel* super = (Panel*) this;
@@ -104,26 +148,19 @@ AvailableMetersPanel* AvailableMetersPanel_new(Settings* settings, Header* heade
    this->scr = scr;
 
    Panel_setHeader(super, "Available meters");
-   // Platform_meterTypes[0] should be always (&CPUMeter_class), which we will
-   // handle separately in the code below.
-   for (int i = 1; Platform_meterTypes[i]; i++) {
+   // Platform_meterTypes[0] should be always (&CPUMeter_class) which we will
+   // handle separately in the code below.  Likewise, identifiers for Dynamic
+   // Meters are handled separately - similar to CPUs, this allows generation
+   // of multiple different Meters (also using 'param' to distinguish them).
+   for (unsigned int i = 1; Platform_meterTypes[i]; i++) {
       const MeterClass* type = Platform_meterTypes[i];
       assert(type != &CPUMeter_class);
-      const char* label = type->description ? type->description : type->uiName;
-      Panel_add(super, (Object*) ListItem_new(label, i << 16));
-   }
-   // Handle (&CPUMeter_class)
-   const MeterClass* type = &CPUMeter_class;
-   unsigned int cpus = pl->cpuCount;
-   if (cpus > 1) {
-      Panel_add(super, (Object*) ListItem_new("CPU average", 0));
-      for (unsigned int i = 1; i <= cpus; i++) {
-         char buffer[50];
-         xSnprintf(buffer, sizeof(buffer), "%s %d", type->uiName, Settings_cpuId(this->settings, i - 1));
-         Panel_add(super, (Object*) ListItem_new(buffer, i));
-      }
-   } else {
-      Panel_add(super, (Object*) ListItem_new("CPU", 1));
+      if (type == &DynamicMeter_class)
+         AvailableMetersPanel_addDynamicMeters(super, pl, i);
+      else
+         AvailableMetersPanel_addPlatformMeter(super, type, i);
    }
+   AvailableMetersPanel_addCPUMeters(super, &CPUMeter_class, pl);
+
    return this;
 }
diff --git a/CPUMeter.c b/CPUMeter.c
index 1e30ce34..0bea79fd 100644
--- a/CPUMeter.c
+++ b/CPUMeter.c
@@ -50,6 +50,14 @@ static void CPUMeter_init(Meter* this) {
    }
 }
 
+// Custom uiName runtime logic to include the param (processor)
+static void CPUMeter_getUiName(const Meter* this, char* buffer, size_t length) {
+   if (this->param > 0)
+      xSnprintf(buffer, sizeof(length), "%s %u", Meter_uiName(this), this->param);
+   else
+      xSnprintf(buffer, sizeof(length), "%s", Meter_uiName(this));
+}
+
 static void CPUMeter_updateValues(Meter* this) {
    unsigned int cpu = this->param;
    if (cpu > this->pl->cpuCount) {
@@ -326,6 +334,7 @@ const MeterClass CPUMeter_class = {
       .display = CPUMeter_display
    },
    .updateValues = CPUMeter_updateValues,
+   .getUiName = CPUMeter_getUiName,
    .defaultMode = BAR_METERMODE,
    .maxItems = CPU_METER_ITEMCOUNT,
    .total = 100.0,
diff --git a/CRT.c b/CRT.c
index 5353c7b7..6418f9ad 100644
--- a/CRT.c
+++ b/CRT.c
@@ -195,6 +195,15 @@ static int CRT_colorSchemes[LAST_COLORSCHEME][LAST_COLORELEMENT] = {
       [ZFS_COMPRESSED] = ColorPair(Blue, Black),
       [ZFS_RATIO] = ColorPair(Magenta, Black),
       [ZRAM] = ColorPair(Yellow, Black),
+      [DYNAMIC_GRAY] = ColorPairGrayBlack,
+      [DYNAMIC_DARKGRAY] = A_BOLD | ColorPairGrayBlack,
+      [DYNAMIC_RED] = ColorPair(Red, Black),
+      [DYNAMIC_GREEN] = ColorPair(Green, Black),
+      [DYNAMIC_BLUE] = ColorPair(Blue, Black),
+      [DYNAMIC_CYAN] = ColorPair(Cyan, Black),
+      [DYNAMIC_MAGENTA] = ColorPair(Magenta, Black),
+      [DYNAMIC_YELLOW] = ColorPair(Yellow, Black),
+      [DYNAMIC_WHITE] = ColorPair(White, Black),
    },
    [COLORSCHEME_MONOCHROME] = {
       [RESET_COLOR] = A_NORMAL,
@@ -288,6 +297,15 @@ static int CRT_colorSchemes[LAST_COLORSCHEME][LAST_COLORELEMENT] = {
       [ZFS_COMPRESSED] = A_BOLD,
       [ZFS_RATIO] = A_BOLD,
       [ZRAM] = A_NORMAL,
+      [DYNAMIC_GRAY] = A_DIM,
+      [DYNAMIC_DARKGRAY] = A_DIM,
+      [DYNAMIC_RED] = A_BOLD,
+      [DYNAMIC_GREEN] = A_NORMAL,
+      [DYNAMIC_BLUE] = A_NORMAL,
+      [DYNAMIC_CYAN] = A_BOLD,
+      [DYNAMIC_MAGENTA] = A_NORMAL,
+      [DYNAMIC_YELLOW] = A_NORMAL,
+      [DYNAMIC_WHITE] = A_BOLD,
    },
    [COLORSCHEME_BLACKONWHITE] = {
       [RESET_COLOR] = ColorPair(Black, White),
@@ -380,7 +398,16 @@ static int CRT_colorSchemes[LAST_COLORSCHEME][LAST_COLORELEMENT] = {
       [ZFS_OTHER] = ColorPair(Magenta, White),
       [ZFS_COMPRESSED] = ColorPair(Cyan, White),
       [ZFS_RATIO] = ColorPair(Magenta, White),
-      [ZRAM] = ColorPair(Yellow, White)
+      [ZRAM] = ColorPair(Yellow, White),
+      [DYNAMIC_GRAY] = ColorPair(Black, White),
+      [DYNAMIC_DARKGRAY] = A_BOLD | ColorPair(Black, White),
+      [DYNAMIC_RED] = ColorPair(Red, White),
+      [DYNAMIC_GREEN] = ColorPair(Green, White),
+      [DYNAMIC_BLUE] = ColorPair(Blue, White),
+      [DYNAMIC_CYAN] = ColorPair(Yellow, White),
+      [DYNAMIC_MAGENTA] = ColorPair(Magenta, White),
+      [DYNAMIC_YELLOW] = ColorPair(Yellow, White),
+      [DYNAMIC_WHITE] = A_BOLD | ColorPair(Black, White),
    },
    [COLORSCHEME_LIGHTTERMINAL] = {
       [RESET_COLOR] = ColorPair(Black, Black),
@@ -474,6 +501,15 @@ static int CRT_colorSchemes[LAST_COLORSCHEME][LAST_COLORELEMENT] = {
       [ZFS_COMPRESSED] = ColorPair(Cyan, Black),
       [ZFS_RATIO] = A_BOLD | ColorPair(Magenta, Black),
       [ZRAM] = ColorPair(Yellow, Black),
+      [DYNAMIC_GRAY] = ColorPairGrayBlack,
+      [DYNAMIC_DARKGRAY] = A_BOLD | ColorPairGrayBlack,
+      [DYNAMIC_RED] = ColorPair(Red, Black),
+      [DYNAMIC_GREEN] = ColorPair(Green, Black),
+      [DYNAMIC_BLUE] = ColorPair(Blue, Black),
+      [DYNAMIC_CYAN] = ColorPair(Cyan, Black),
+      [DYNAMIC_MAGENTA] = ColorPair(Magenta, Black),
+      [DYNAMIC_YELLOW] = ColorPair(Yellow, Black),
+      [DYNAMIC_WHITE] = ColorPairWhiteDefault,
    },
    [COLORSCHEME_MIDNIGHT] = {
       [RESET_COLOR] = ColorPair(White, Blue),
@@ -567,6 +603,15 @@ static int CRT_colorSchemes[LAST_COLORSCHEME][LAST_COLORELEMENT] = {
       [ZFS_COMPRESSED] = A_BOLD | ColorPair(White, Blue),
       [ZFS_RATIO] = A_BOLD | ColorPair(Magenta, Blue),
       [ZRAM] = A_BOLD | ColorPair(Yellow, Blue),
+      [DYNAMIC_GRAY] = ColorPairGrayBlack,
+      [DYNAMIC_DARKGRAY] = A_BOLD | ColorPairGrayBlack,
+      [DYNAMIC_RED] = ColorPair(Red, Blue),
+      [DYNAMIC_GREEN] = ColorPair(Green, Blue),
+      [DYNAMIC_BLUE] = ColorPair(Black, Blue),
+      [DYNAMIC_CYAN] = ColorPair(Cyan, Blue),
+      [DYNAMIC_MAGENTA] = ColorPair(Magenta, Blue),
+      [DYNAMIC_YELLOW] = ColorPair(Yellow, Blue),
+      [DYNAMIC_WHITE] = ColorPair(White, Blue),
    },
    [COLORSCHEME_BLACKNIGHT] = {
       [RESET_COLOR] = ColorPair(Cyan, Black),
@@ -658,6 +703,15 @@ static int CRT_colorSchemes[LAST_COLORSCHEME][LAST_COLORELEMENT] = {
       [ZFS_COMPRESSED] = ColorPair(Blue, Black),
       [ZFS_RATIO] = ColorPair(Magenta, Black),
       [ZRAM] = ColorPair(Yellow, Black),
+      [DYNAMIC_GRAY] = ColorPairGrayBlack,
+      [DYNAMIC_DARKGRAY] = A_BOLD | ColorPairGrayBlack,
+      [DYNAMIC_RED] = ColorPair(Red, Black),
+      [DYNAMIC_GREEN] = ColorPair(Green, Black),
+      [DYNAMIC_BLUE] = ColorPair(Blue, Black),
+      [DYNAMIC_CYAN] = ColorPair(Cyan, Black),
+      [DYNAMIC_MAGENTA] = ColorPair(Magenta, Black),
+      [DYNAMIC_YELLOW] = ColorPair(Yellow, Black),
+      [DYNAMIC_WHITE] = ColorPair(White, Black),
    },
    [COLORSCHEME_BROKENGRAY] = { 0 } // dynamically generated.
 };
diff --git a/CRT.h b/CRT.h
index e85247bd..9f3ecb44 100644
--- a/CRT.h
+++ b/CRT.h
@@ -131,6 +131,15 @@ typedef enum ColorElements_ {
    ZFS_COMPRESSED,
    ZFS_RATIO,
    ZRAM,
+   DYNAMIC_GRAY,
+   DYNAMIC_DARKGRAY,
+   DYNAMIC_RED,
+   DYNAMIC_GREEN,
+   DYNAMIC_BLUE,
+   DYNAMIC_CYAN,
+   DYNAMIC_MAGENTA,
+   DYNAMIC_YELLOW,
+   DYNAMIC_WHITE,
    LAST_COLORELEMENT
 } ColorElements;
 
diff --git a/CommandLine.c b/CommandLine.c
index 60582dcf..4a721a3d 100644
--- a/CommandLine.c
+++ b/CommandLine.c
@@ -22,6 +22,7 @@ in the source distribution for its full text.
 
 #include "Action.h"
 #include "CRT.h"
+#include "DynamicMeter.h"
 #include "Hashtable.h"
 #include "Header.h"
 #include "IncSet.h"
@@ -288,7 +289,8 @@ int CommandLine_run(const char* name, int argc, char** argv) {
    Process_setupColumnWidths();
 
    UsersTable* ut = UsersTable_new();
-   ProcessList* pl = ProcessList_new(ut, flags.pidMatchList, flags.userId);
+   Hashtable* dm = DynamicMeters_new();
+   ProcessList* pl = ProcessList_new(ut, dm, flags.pidMatchList, flags.userId);
 
    Settings* settings = Settings_new(pl->cpuCount);
    pl->settings = settings;
diff --git a/DynamicMeter.c b/DynamicMeter.c
new file mode 100644
index 00000000..7b39fdaa
--- /dev/null
+++ b/DynamicMeter.c
@@ -0,0 +1,98 @@
+/*
+htop - DynamicMeter.c
+(C) 2021 htop dev team
+(C) 2021 Red Hat, Inc.  All Rights Reserved.
+Released under the GNU GPLv2, see the COPYING file
+in the source distribution for its full text.
+*/
+#include "config.h" // IWYU pragma: keep
+
+#include "DynamicMeter.h"
+
+#include "CRT.h"
+#include "Object.h"
+#include "Platform.h"
+#include "ProcessList.h"
+#include "RichString.h"
+#include "XUtils.h"
+
+
+static const int DynamicMeter_attributes[] = {
+   DYNAMIC_GRAY,
+   DYNAMIC_DARKGRAY,
+   DYNAMIC_RED,
+   DYNAMIC_GREEN,
+   DYNAMIC_BLUE,
+   DYNAMIC_CYAN,
+   DYNAMIC_MAGENTA,
+   DYNAMIC_YELLOW,
+   DYNAMIC_WHITE
+};
+
+Hashtable* DynamicMeters_new(void) {
+   return Platform_dynamicMeters();
+}
+
+typedef struct {
+   unsigned int key;
+   const char* name;
+} DynamicIterator;
+
+static void DynamicMeter_compare(ht_key_t key, void* value, void* data) {
+   const DynamicMeter* meter = (const DynamicMeter*)value;
+   DynamicIterator* iter = (DynamicIterator*)data;
+   if (String_eq(iter->name, meter->name))
+      iter->key = key;
+}
+
+unsigned int DynamicMeter_search(const ProcessList* pl, const char* name) {
+   DynamicIterator iter = { .key = 0, .name = name };
+   if (pl->dynamicMeters)
+      Hashtable_foreach(pl->dynamicMeters, DynamicMeter_compare, &iter);
+   return iter.key;
+}
+
+const char* DynamicMeter_lookup(const ProcessList* pl, unsigned int key) {
+   const DynamicMeter* meter = Hashtable_get(pl->dynamicMeters, key);
+   return meter ? meter->name : NULL;
+}
+
+static void DynamicMeter_init(Meter* meter) {
+   Platform_dynamicMeterInit(meter);
+}
+
+static void DynamicMeter_updateValues(Meter* meter) {
+   Platform_dynamicMeterUpdateValues(meter);
+}
+
+static void DynamicMeter_display(const Object* cast, RichString* out) {
+   const Meter* meter = (const Meter*)cast;
+   Platform_dynamicMeterDisplay(meter, out);
+}
+
+static void DynamicMeter_getUiName(const Meter* this, char* name, size_t length) {
+   const ProcessList* pl = this->pl;
+   const DynamicMeter* meter = Hashtable_get(pl->dynamicMeters, this->param);
+   if (meter) {
+      const char* uiName = meter->caption ? meter->caption : meter->name;
+      xSnprintf(name, length, "%s", uiName);
+   }
+}
+
+const MeterClass DynamicMeter_class = {
+   .super = {
+      .extends = Class(Meter),
+      .delete = Meter_delete,
+      .display = DynamicMeter_display
+   },
+   .init = DynamicMeter_init,
+   .updateValues = DynamicMeter_updateValues,
+   .getUiName = DynamicMeter_getUiName,
+   .defaultMode = TEXT_METERMODE,
+   .maxItems = 0,
+   .total = 100.0,
+   .attributes = DynamicMeter_attributes,
+   .name = "Dynamic",
+   .uiName = "Dynamic",
+   .caption = "",
+};
diff --git a/DynamicMeter.h b/DynamicMeter.h
new file mode 100644
index 00000000..3d1bc9f2
--- /dev/null
+++ b/DynamicMeter.h
@@ -0,0 +1,25 @@
+#ifndef HEADER_DynamicMeter
+#define HEADER_DynamicMeter
+
+#include "Meter.h"
+
+
+typedef struct DynamicMeter_ {
+   char name[32];  /* unique name, cannot contain spaces */
+   char* caption;
+   char* description;
+   unsigned int type;
+   double maximum;
+
+   void* dynamicData;  /* platform-specific meter data */
+} DynamicMeter;
+
+Hashtable* DynamicMeters_new(void);
+
+const char* DynamicMeter_lookup(const ProcessList* pl, unsigned int param);
+
+unsigned int DynamicMeter_search(const ProcessList* pl, const char* name);
+
+extern const MeterClass DynamicMeter_class;
+
+#endif
diff --git a/Header.c b/Header.c
index d2d7f694..0fdafea5 100644
--- a/Header.c
+++ b/Header.c
@@ -13,6 +13,8 @@ in the source distribution for its full text.
 #include <string.h>
 
 #include "CRT.h"
+#include "CPUMeter.h"
+#include "DynamicMeter.h"
 #include "Macros.h"
 #include "Object.h"
 #include "Platform.h"
@@ -70,7 +72,10 @@ void Header_writeBackToSettings(const Header* this) {
       for (int i = 0; i < len; i++) {
          const Meter* meter = (Meter*) Vector_get(vec, i);
          char* name;
-         if (meter->param) {
+         if (meter->param && As_Meter(meter) == &DynamicMeter_class) {
+            const char* dynamic = DynamicMeter_lookup(this->pl, meter->param);
+            xAsprintf(&name, "%s(%s)", As_Meter(meter)->name, dynamic);
+         } else if (meter->param && As_Meter(meter) == &CPUMeter_class) {
             xAsprintf(&name, "%s(%u)", As_Meter(meter)->name, meter->param);
          } else {
             xAsprintf(&name, "%s", As_Meter(meter)->name);
@@ -87,9 +92,13 @@ MeterModeId Header_addMeterByName(Header* this, const char* name, int column) {
    char* paren = strchr(name, '(');
    unsigned int param = 0;
    if (paren) {
-      int ok = sscanf(paren, "(%10u)", &param);
-      if (!ok)
-         param = 0;
+      char* end, dynamic[32] = {0};
+      int ok = sscanf(paren, "(%10u)", &param); // CPUMeter
+      if (!ok) {
+         ok = sscanf(paren, "(%30s)", dynamic); // DynamicMeter
+         if (ok && (end = strrchr(dynamic, ')'))) *end = '\0';
+         param = ok ? DynamicMeter_search(this->pl, dynamic) : 0;
+      }
       *paren = '\0';
    }
    MeterModeId mode = TEXT_METERMODE;
diff --git a/Makefile.am b/Makefile.am
index 079bcd86..ce50d0f7 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -39,6 +39,7 @@ myhtopsources = \
 	DateTimeMeter.c \
 	DiskIOMeter.c \
 	DisplayOptionsPanel.c \
+	DynamicMeter.c \
 	EnvScreen.c \
 	FunctionBar.c \
 	Hashtable.c \
@@ -93,6 +94,7 @@ myhtopheaders = \
 	DateTimeMeter.h \
 	DiskIOMeter.h \
 	DisplayOptionsPanel.h \
+	DynamicMeter.h \
 	EnvScreen.h \
 	FunctionBar.h \
 	Hashtable.h \
@@ -357,6 +359,7 @@ endif
 # --------------------------
 
 pcp_platform_headers = \
+	pcp/PCPDynamicMeter.h \
 	pcp/PCPProcess.h \
 	pcp/PCPProcessList.h \
 	pcp/Platform.h \
@@ -369,6 +372,7 @@ pcp_platform_headers = \
 	zfs/ZfsCompressedArcMeter.h
 
 pcp_platform_sources = \
+	pcp/PCPDynamicMeter.c \
 	pcp/PCPProcess.c \
 	pcp/PCPProcessList.c \
 	pcp/Platform.c \
diff --git a/Meter.c b/Meter.c
index ae867e1c..0052773c 100644
--- a/Meter.c
+++ b/Meter.c
@@ -138,14 +138,13 @@ ListItem* Meter_toListItem(const Meter* this, bool moving) {
    } else {
       mode[0] = '\0';
    }
-   char number[10];
-   if (this->param > 0) {
-      xSnprintf(number, sizeof(number), " %u", this->param);
-   } else {
-      number[0] = '\0';
-   }
+   char name[32];
+   if (Meter_getUiNameFn(this))
+      Meter_getUiName(this, name, sizeof(name));
+   else
+      xSnprintf(name, sizeof(name), "%s", Meter_uiName(this));
    char buffer[50];
-   xSnprintf(buffer, sizeof(buffer), "%s%s%s", Meter_uiName(this), number, mode);
+   xSnprintf(buffer, sizeof(buffer), "%s%s", name, mode);
    ListItem* li = ListItem_new(buffer, 0);
    li->moving = moving;
    return li;
diff --git a/Meter.h b/Meter.h
index cd9c9b8e..40cad332 100644
--- a/Meter.h
+++ b/Meter.h
@@ -53,14 +53,16 @@ typedef void(*Meter_Done)(Meter*);
 typedef void(*Meter_UpdateMode)(Meter*, int);
 typedef void(*Meter_UpdateValues)(Meter*);
 typedef void(*Meter_Draw)(Meter*, int, int, int);
+typedef void(*Meter_GetUiName)(const Meter*, char*, size_t);
 
 typedef struct MeterClass_ {
    const ObjectClass super;
    const Meter_Init init;
    const Meter_Done done;
    const Meter_UpdateMode updateMode;
-   const Meter_Draw draw;
    const Meter_UpdateValues updateValues;
+   const Meter_Draw draw;
+   const Meter_GetUiName getUiName;
    const int defaultMode;
    const double total;
    const int* const attributes;
@@ -80,6 +82,8 @@ typedef struct MeterClass_ {
 #define Meter_drawFn(this_)            As_Meter(this_)->draw
 #define Meter_doneFn(this_)            As_Meter(this_)->done
 #define Meter_updateValues(this_)      As_Meter(this_)->updateValues((Meter*)(this_))
+#define Meter_getUiNameFn(this_)       As_Meter(this_)->getUiName
+#define Meter_getUiName(this_,n_,l_)   As_Meter(this_)->getUiName((const Meter*)(this_),n_,l_)
 #define Meter_defaultMode(this_)       As_Meter(this_)->defaultMode
 #define Meter_attributes(this_)        As_Meter(this_)->attributes
 #define Meter_name(this_)              As_Meter(this_)->name
diff --git a/ProcessList.c b/ProcessList.c
index da5d7a91..82f719f8 100644
--- a/ProcessList.c
+++ b/ProcessList.c
@@ -19,7 +19,7 @@ in the source distribution for its full text.
 #include "XUtils.h"
 
 
-ProcessList* ProcessList_init(ProcessList* this, const ObjectClass* klass, UsersTable* usersTable, Hashtable* pidMatchList, uid_t userId) {
+ProcessList* ProcessList_init(ProcessList* this, const ObjectClass* klass, UsersTable* usersTable, Hashtable* dynamicMeters, Hashtable* pidMatchList, uid_t userId) {
    this->processes = Vector_new(klass, true, DEFAULT_SIZE);
    this->processes2 = Vector_new(klass, true, DEFAULT_SIZE); // tree-view auxiliary buffer
 
@@ -29,6 +29,7 @@ ProcessList* ProcessList_init(ProcessList* this, const ObjectClass* klass, Users
 
    this->usersTable = usersTable;
    this->pidMatchList = pidMatchList;
+   this->dynamicMeters = dynamicMeters;
 
    this->userId = userId;
 
diff --git a/ProcessList.h b/ProcessList.h
index 32bdfa18..da4a50da 100644
--- a/ProcessList.h
+++ b/ProcessList.h
@@ -50,6 +50,8 @@ typedef struct ProcessList_ {
    Hashtable* displayTreeSet;
    Hashtable* draftingTreeSet;
 
+   Hashtable* dynamicMeters;  /* runtime-discovered meters */
+
    struct timeval realtime;   /* time of the current sample */
    uint64_t realtimeMs;       /* current time in milliseconds */
    uint64_t monotonicMs;      /* same, but from monotonic clock */
@@ -84,12 +86,12 @@ typedef struct ProcessList_ {
    unsigned int cpuCount;
 } ProcessList;
 
-ProcessList* ProcessList_new(UsersTable* usersTable, Hashtable* pidMatchList, uid_t userId);
+ProcessList* ProcessList_new(UsersTable* usersTable, Hashtable* dynamicMeters, Hashtable* pidMatchList, uid_t userId);
 void ProcessList_delete(ProcessList* pl);
 void ProcessList_goThroughEntries(ProcessList* super, bool pauseProcessUpdate);
 
 
-ProcessList* ProcessList_init(ProcessList* this, const ObjectClass* klass, UsersTable* usersTable, Hashtable* pidMatchList, uid_t userId);
+ProcessList* ProcessList_init(ProcessList* this, const ObjectClass* klass, UsersTable* usersTable, Hashtable* dynamicMeters, Hashtable* pidMatchList, uid_t userId);
 
 void ProcessList_done(ProcessList* this);
 
diff --git a/darwin/DarwinProcessList.c b/darwin/DarwinProcessList.c
index 900677ae..91d62c4a 100644
--- a/darwin/DarwinProcessList.c
+++ b/darwin/DarwinProcessList.c
@@ -128,10 +128,10 @@ static struct kinfo_proc* ProcessList_getKInfoProcs(size_t* count) {
    CRT_fatalError("Unable to get kinfo_procs");
 }
 
-ProcessList* ProcessList_new(UsersTable* usersTable, Hashtable* pidMatchList, uid_t userId) {
+ProcessList* ProcessList_new(UsersTable* usersTable, Hashtable* dynamicMeters, Hashtable* pidMatchList, uid_t userId) {
    DarwinProcessList* this = xCalloc(1, sizeof(DarwinProcessList));
 
-   ProcessList_init(&this->super, Class(DarwinProcess), usersTable, pidMatchList, userId);
+   ProcessList_init(&this->super, Class(DarwinProcess), usersTable, dynamicMeters, pidMatchList, userId);
 
    /* Initialize the CPU information */
    this->super.cpuCount = ProcessList_allocateCPULoadInfo(&this->prev_load);
diff --git a/darwin/DarwinProcessList.h b/darwin/DarwinProcessList.h
index 1ae2f2b9..bd39ab0e 100644
--- a/darwin/DarwinProcessList.h
+++ b/darwin/DarwinProcessList.h
@@ -28,7 +28,7 @@ typedef struct DarwinProcessList_ {
    ZfsArcStats zfs;
 } DarwinProcessList;
 
-ProcessList* ProcessList_new(UsersTable* usersTable, Hashtable* pidMatchList, uid_t userId);
+ProcessList* ProcessList_new(UsersTable* usersTable, Hashtable* dynamicMeters, Hashtable* pidMatchList, uid_t userId);
 
 void ProcessList_delete(ProcessList* this);
 
diff --git a/darwin/Platf