Compare all percentage fields with compareRealNumbers()

The SPACESHIP_NUMBER() macro does not work well with floating point
values that are possible to be NaNs. Change the compare logic of all
percentage fields of Process entries to use compareRealNumbers().

Signed-off-by: Kang-Che Sung <explorer09@gmail.com>

6 files changed, 25 insertions, 29 deletions

diff --git a/Process.c b/Process.c
index 7e2d11af..7244ad9f 100644
--- a/Process.c
+++ b/Process.c
@@ -1182,7 +1182,7 @@ int Process_compareByKey_Base(const Process* p1, const Process* p2, ProcessField
    switch (key) {
    case PERCENT_CPU:
    case PERCENT_NORM_CPU:
-      return SPACESHIP_NUMBER(p1->percent_cpu, p2->percent_cpu);
+      return compareRealNumbers(p1->percent_cpu, p2->percent_cpu);
    case PERCENT_MEM:
       return SPACESHIP_NUMBER(p1->m_resident, p2->m_resident);
    case COMM:
diff --git a/XUtils.c b/XUtils.c
index 9b7735f6..1af0dd4f 100644
--- a/XUtils.c
+++ b/XUtils.c
@@ -12,6 +12,7 @@ in the source distribution for its full text.
 #include <assert.h>
 #include <errno.h>
 #include <fcntl.h>
+#include <math.h>
 #include <stdarg.h>
 #include <stdint.h>
 #include <stdlib.h>
@@ -339,6 +340,16 @@ ssize_t full_write(int fd, const void* buf, size_t count) {
    return written;
 }
 
+/* Compares floating point values for ordering data entries. In this function,
+   NaN is considered "less than" any other floating point value (regardless of
+   sign), and two NaNs are considered "equal" regardless of payload. */
+int compareRealNumbers(double a, double b) {
+   int result = isgreater(a, b) - isgreater(b, a);
+   if (result)
+      return result;
+   return !isNaN(a) - !isNaN(b);
+}
+
 /* Computes the sum of all positive floating point values in an array.
    NaN values in the array are skipped. The returned sum will always be
    nonnegative. */
diff --git a/XUtils.h b/XUtils.h
index 68e370b0..fd1087d5 100644
--- a/XUtils.h
+++ b/XUtils.h
@@ -82,6 +82,11 @@ ssize_t xReadfileat(openat_arg_t dirfd, const char* pathname, void* buffer, size
 ATTR_ACCESS3_R(2, 3)
 ssize_t full_write(int fd, const void* buf, size_t count);
 
+/* Compares floating point values for ordering data entries. In this function,
+   NaN is considered "less than" any other floating point value (regardless of
+   sign), and two NaNs are considered "equal" regardless of payload. */
+int compareRealNumbers(double a, double b);
+
 /* Computes the sum of all positive floating point values in an array.
    NaN values in the array are skipped. The returned sum will always be
    nonnegative. */
diff --git a/linux/LinuxProcess.c b/linux/LinuxProcess.c
index 0a88644c..87561818 100644
--- a/linux/LinuxProcess.c
+++ b/linux/LinuxProcess.c
@@ -310,16 +310,6 @@ static void LinuxProcess_writeField(const Process* this, RichString* str, Proces
    RichString_appendAscii(str, attr, buffer);
 }
 
-/* Compares floating point values for ordering data entries. In this function,
-   NaN is considered "less than" any other floating point value (regardless of
-   sign), and two NaNs are considered "equal" regardless of payload. */
-static int compareRealNumbers(double a, double b) {
-   int result = isgreater(a, b) - isgreater(b, a);
-   if (result)
-      return result;
-   return !isNaN(a) - !isNaN(b);
-}
-
 static int LinuxProcess_compareByKey(const Process* v1, const Process* v2, ProcessField key) {
    const LinuxProcess* p1 = (const LinuxProcess*)v1;
    const LinuxProcess* p2 = (const LinuxProcess*)v2;
@@ -385,11 +375,11 @@ static int LinuxProcess_compareByKey(const Process* v1, const Process* v2, Proce
       return SPACESHIP_NUMBER(p1->oom, p2->oom);
    #ifdef HAVE_DELAYACCT
    case PERCENT_CPU_DELAY:
-      return SPACESHIP_NUMBER(p1->cpu_delay_percent, p2->cpu_delay_percent);
+      return compareRealNumbers(p1->cpu_delay_percent, p2->cpu_delay_percent);
    case PERCENT_IO_DELAY:
-      return SPACESHIP_NUMBER(p1->blkio_delay_percent, p2->blkio_delay_percent);
+      return compareRealNumbers(p1->blkio_delay_percent, p2->blkio_delay_percent);
    case PERCENT_SWAP_DELAY:
-      return SPACESHIP_NUMBER(p1->swapin_delay_percent, p2->swapin_delay_percent);
+      return compareRealNumbers(p1->swapin_delay_percent, p2->swapin_delay_percent);
    #endif
    case IO_PRIORITY:
       return SPACESHIP_NUMBER(LinuxProcess_effectiveIOPriority(p1), LinuxProcess_effectiveIOPriority(p2));
diff --git a/pcp/PCPDynamicColumn.c b/pcp/PCPDynamicColumn.c
index 23b896e6..2481d81d 100644
--- a/pcp/PCPDynamicColumn.c
+++ b/pcp/PCPDynamicColumn.c
@@ -338,9 +338,9 @@ int PCPDynamicColumn_compareByKey(const PCPProcess* p1, const PCPProcess* p2, Pr
       case PM_TYPE_U64:
          return SPACESHIP_NUMBER(atom2.ull, atom1.ull);
       case PM_TYPE_FLOAT:
-         return SPACESHIP_NUMBER(atom2.f, atom1.f);
+         return compareRealNumbers(atom2.f, atom1.f);
       case PM_TYPE_DOUBLE:
-         return SPACESHIP_NUMBER(atom2.d, atom1.d);
+         return compareRealNumbers(atom2.d, atom1.d);
       default:
          break;
    }
diff --git a/pcp/PCPProcess.c b/pcp/PCPProcess.c
index 2cb27814..eadc9eb4 100644
--- a/pcp/PCPProcess.c
+++ b/pcp/PCPProcess.c
@@ -199,16 +199,6 @@ static void PCPProcess_writeField(const Process* this, RichString* str, ProcessF
    RichString_appendWide(str, attr, buffer);
 }
 
-/* Compares floating point values for ordering data entries. In this function,
-   NaN is considered "less than" any other floating point value (regardless of
-   sign), and two NaNs are considered "equal" regardless of payload. */
-static int compareRealNumbers(double a, double b) {
-   int result = isgreater(a, b) - isgreater(b, a);
-   if (result)
-      return result;
-   return !isNaN(a) - !isNaN(b);
-}
-
 static int PCPProcess_compareByKey(const Process* v1, const Process* v2, ProcessField key) {
    const PCPProcess* p1 = (const PCPProcess*)v1;
    const PCPProcess* p2 = (const PCPProcess*)v2;
@@ -263,11 +253,11 @@ static int PCPProcess_compareByKey(const Process* v1, const Process* v2, Process
    case OOM:
       return SPACESHIP_NUMBER(p1->oom, p2->oom);
    case PERCENT_CPU_DELAY:
-      return SPACESHIP_NUMBER(p1->cpu_delay_percent, p2->cpu_delay_percent);
+      return compareRealNumbers(p1->cpu_delay_percent, p2->cpu_delay_percent);
    case PERCENT_IO_DELAY:
-      return SPACESHIP_NUMBER(p1->blkio_delay_percent, p2->blkio_delay_percent);
+      return compareRealNumbers(p1->blkio_delay_percent, p2->blkio_delay_percent);
    case PERCENT_SWAP_DELAY:
-      return SPACESHIP_NUMBER(p1->swapin_delay_percent, p2->swapin_delay_percent);
+      return compareRealNumbers(p1->swapin_delay_percent, p2->swapin_delay_percent);
    case CTXT:
       return SPACESHIP_NUMBER(p1->ctxt_diff, p2->ctxt_diff);
    case SECATTR: