Allow meters in text mode to span empty neighbors to the right

Closes: #484

Header.c

@@ -150,35 +150,71 @@ void Header_reinit(Header* this) {
 }
 
 void Header_draw(const Header* this) {
-   int height = this->height;
-   int pad = this->pad;
+   const int height = this->height;
+   const int pad = this->pad;
    attrset(CRT_colors[RESET_COLOR]);
    for (int y = 0; y < height; y++) {
       mvhline(y, 0, ' ', COLS);
    }
-   int width = COLS / this->nrColumns - (pad * this->nrColumns - 1) - 1;
+   const int width = COLS / this->nrColumns - (pad * this->nrColumns - 1) - 1;
    int x = pad;
 
    Header_forEachColumn(this, col) {
       Vector* meters = this->columns[col];
       for (int y = (pad / 2), i = 0; i < Vector_size(meters); i++) {
          Meter* meter = (Meter*) Vector_get(meters, i);
-         meter->draw(meter, x, y, width);
+
+         int actualWidth;
+         if (meter->mode == TEXT_METERMODE)
+            actualWidth = meter->columnWidthCount * width + (meter->columnWidthCount - 1) * (2 * pad + 1);
+         else
+            actualWidth = width;
+
+         meter->draw(meter, x, y, actualWidth);
          y += meter->h;
       }
       x += width + pad;
    }
 }
 
+/*
+ * Calculate how many columns the current meter is allowed to span,
+ * by counting how many columns to the right are empty or contain a BlankMeter.
+ * Returns the number of columns to span, i.e. if the direct neighbor is occupied 1.
+ */
+static int calcColumnWidthCount(const Header* this, const Meter* curMeter, const int pad, const int curColumn, const int curHeight) {
+   for (int i = curColumn + 1; i < this->nrColumns; i++) {
+      const Vector* meters = this->columns[i];
+
+      int height = pad;
+      for (int j = 0; j < Vector_size(meters); j++) {
+         const Meter* meter = (const Meter*) Vector_get(meters, j);
+
+         if (height >= curHeight + curMeter->h)
+            break;
+
+         height += meter->h;
+         if (height <= curHeight)
+            continue;
+
+         if (!Object_isA((const Object*) meter, (const ObjectClass*) &BlankMeter_class))
+            return i - curColumn;
+      }
+   }
+
+   return this->nrColumns - curColumn;
+}
+
 int Header_calculateHeight(Header* this) {
-   int pad = this->settings->headerMargin ? 2 : 0;
+   const int pad = this->settings->headerMargin ? 2 : 0;
    int maxHeight = pad;
 
    Header_forEachColumn(this, col) {
       const Vector* meters = this->columns[col];
       int height = pad;
       for (int i = 0; i < Vector_size(meters); i++) {
-         const Meter* meter = (const Meter*) Vector_get(meters, i);
+         Meter* meter = (Meter*) Vector_get(meters, i);
+         meter->columnWidthCount = calcColumnWidthCount(this, meter, pad, col, height);
          height += meter->h;
       }
       maxHeight = MAXIMUM(maxHeight, height);

Meter.h

@@ -98,6 +98,7 @@ struct Meter_ {
    int param;
    GraphData* drawData;
    int h;
+   int columnWidthCount;      /*<< only used internally by the Header */
    const ProcessList* pl;
    uint8_t curItems;
    const int* curAttributes;

Object.c

@@ -15,8 +15,6 @@ const ObjectClass Object_class = {
    .extends = NULL
 };
 
-#ifndef NDEBUG
-
 bool Object_isA(const Object* o, const ObjectClass* klass) {
    if (!o)
       return false;
@@ -29,5 +27,3 @@ bool Object_isA(const Object* o, const ObjectClass* klass) {
 
    return false;
 }
-
-#endif /* NDEBUG */

Object.h

@@ -57,10 +57,6 @@ typedef union {
 
 extern const ObjectClass Object_class;
 
-#ifndef NDEBUG
-
 bool Object_isA(const Object* o, const ObjectClass* klass);
 
-#endif /* NDEBUG */
-
 #endif