Use sizeof buffer instead of magic number

MemoryMeter.c

@@ -35,15 +35,15 @@ static void MemoryMeter_display(const Object* cast, RichString* out) {
    char buffer[50];
    const Meter* this = (const Meter*)cast;
    RichString_write(out, CRT_colors[METER_TEXT], ":");
-   Meter_humanUnit(buffer, this->total, 50);
+   Meter_humanUnit(buffer, this->total, sizeof(buffer));
    RichString_append(out, CRT_colors[METER_VALUE], buffer);
-   Meter_humanUnit(buffer, this->values[0], 50);
+   Meter_humanUnit(buffer, this->values[0], sizeof(buffer));
    RichString_append(out, CRT_colors[METER_TEXT], " used:");
    RichString_append(out, CRT_colors[MEMORY_USED], buffer);
-   Meter_humanUnit(buffer, this->values[1], 50);
+   Meter_humanUnit(buffer, this->values[1], sizeof(buffer));
    RichString_append(out, CRT_colors[METER_TEXT], " buffers:");
    RichString_append(out, CRT_colors[MEMORY_BUFFERS_TEXT], buffer);
-   Meter_humanUnit(buffer, this->values[2], 50);
+   Meter_humanUnit(buffer, this->values[2], sizeof(buffer));
    RichString_append(out, CRT_colors[METER_TEXT], " cache:");
    RichString_append(out, CRT_colors[MEMORY_CACHE], buffer);
 }

SwapMeter.c

@@ -33,9 +33,9 @@ static void SwapMeter_display(const Object* cast, RichString* out) {
    char buffer[50];
    const Meter* this = (const Meter*)cast;
    RichString_write(out, CRT_colors[METER_TEXT], ":");
-   Meter_humanUnit(buffer, this->total, 50);
+   Meter_humanUnit(buffer, this->total, sizeof(buffer));
    RichString_append(out, CRT_colors[METER_VALUE], buffer);
-   Meter_humanUnit(buffer, this->values[0], 50);
+   Meter_humanUnit(buffer, this->values[0], sizeof(buffer));
    RichString_append(out, CRT_colors[METER_TEXT], " used:");
    RichString_append(out, CRT_colors[METER_VALUE], buffer);
 }

zfs/ZfsArcMeter.c

@@ -50,24 +50,24 @@ static void ZfsArcMeter_display(const Object* cast, RichString* out) {
 
    if (this->values[5] > 0) {
       char buffer[50];
-      Meter_humanUnit(buffer, this->total, 50);
+      Meter_humanUnit(buffer, this->total, sizeof(buffer));
       RichString_append(out, CRT_colors[METER_VALUE], buffer);
-      Meter_humanUnit(buffer, this->values[5], 50);
+      Meter_humanUnit(buffer, this->values[5], sizeof(buffer));
       RichString_append(out, CRT_colors[METER_TEXT], " Used:");
       RichString_append(out, CRT_colors[METER_VALUE], buffer);
-      Meter_humanUnit(buffer, this->values[0], 50);
+      Meter_humanUnit(buffer, this->values[0], sizeof(buffer));
       RichString_append(out, CRT_colors[METER_TEXT], " MFU:");
       RichString_append(out, CRT_colors[ZFS_MFU], buffer);
-      Meter_humanUnit(buffer, this->values[1], 50);
+      Meter_humanUnit(buffer, this->values[1], sizeof(buffer));
       RichString_append(out, CRT_colors[METER_TEXT], " MRU:");
       RichString_append(out, CRT_colors[ZFS_MRU], buffer);
-      Meter_humanUnit(buffer, this->values[2], 50);
+      Meter_humanUnit(buffer, this->values[2], sizeof(buffer));
       RichString_append(out, CRT_colors[METER_TEXT], " Anon:");
       RichString_append(out, CRT_colors[ZFS_ANON], buffer);
-      Meter_humanUnit(buffer, this->values[3], 50);
+      Meter_humanUnit(buffer, this->values[3], sizeof(buffer));
       RichString_append(out, CRT_colors[METER_TEXT], " Hdr:");
       RichString_append(out, CRT_colors[ZFS_HEADER], buffer);
-      Meter_humanUnit(buffer, this->values[4], 50);
+      Meter_humanUnit(buffer, this->values[4], sizeof(buffer));
       RichString_append(out, CRT_colors[METER_TEXT], " Oth:");
       RichString_append(out, CRT_colors[ZFS_OTHER], buffer);
    } else {

zfs/ZfsCompressedArcMeter.c

@@ -47,13 +47,13 @@ static void ZfsCompressedArcMeter_display(const Object* cast, RichString* out) {
 
    if (this->values[0] > 0) {
       char buffer[50];
-      Meter_humanUnit(buffer, this->total, 50);
+      Meter_humanUnit(buffer, this->total, sizeof(buffer));
       RichString_append(out, CRT_colors[METER_VALUE], buffer);
       RichString_append(out, CRT_colors[METER_TEXT], " Uncompressed, ");
-      Meter_humanUnit(buffer, this->values[0], 50);
+      Meter_humanUnit(buffer, this->values[0], sizeof(buffer));
       RichString_append(out, CRT_colors[METER_VALUE], buffer);
       RichString_append(out, CRT_colors[METER_TEXT], " Compressed, ");
-      ZfsCompressedArcMeter_printRatioString(this, buffer, 50);
+      ZfsCompressedArcMeter_printRatioString(this, buffer, sizeof(buffer));
       RichString_append(out, CRT_colors[METER_VALUE], buffer);
       RichString_append(out, CRT_colors[METER_TEXT], " Ratio");
    } else {