Factor out some common functionality in an effort to make

this code more readable.

diff --git a/src/processes.c b/src/processes.c
index beee341..924f6ce 100644 (file)
--- a/src/processes.c
+++ b/src/processes.c
@@ -359,6 +359,31 @@ static int ps_list_match (const char *name, const char *cmdline, procstat_t *ps)
        return (0);
 } /* int ps_list_match */
 
+static void ps_update_counter (
+        _Bool init,
+        derive_t *group_counter,
+        derive_t *curr_counter, unsigned long *curr_value,
+        derive_t new_counter, unsigned long new_value) {
+    if (init)
+    {
+        *curr_value = new_value;
+        *curr_counter += new_value;
+        *group_counter += new_value;
+        return;
+    }
+
+    if (new_counter < *curr_counter)
+    {
+        *curr_value = new_counter + (ULONG_MAX - *curr_counter);
+    }
+    else
+    {
+        *curr_value = new_counter - *curr_counter;
+    }
+    *curr_counter = new_counter;
+    *group_counter += *curr_value;
+}
+
 /* add process entry to 'instances' of process 'name' (or refresh it) */
 static void ps_list_add (const char *name, const char *cmdline, procstat_entry_t *entry)
 {
@@ -370,6 +395,8 @@ static void ps_list_add (const char *name, const char *cmdline, procstat_entry_t
 
        for (ps = list_head_g; ps != NULL; ps = ps->next)
        {
+        _Bool want_init;
+
                if ((ps_list_match (name, cmdline, ps)) == 0)
                        continue;
 
@@ -426,79 +453,27 @@ static void ps_list_add (const char *name, const char *cmdline, procstat_entry_t
                ps->cswitch_vol   += ((pse->cswitch_vol == -1)?0:pse->cswitch_vol);
                ps->cswitch_invol += ((pse->cswitch_invol == -1)?0:pse->cswitch_invol);
 
-               if ((entry->vmem_minflt_counter == 0)
-                               && (entry->vmem_majflt_counter == 0))
-               {
-                       pse->vmem_minflt_counter += entry->vmem_minflt;
-                       pse->vmem_minflt = entry->vmem_minflt;
-
-                       pse->vmem_majflt_counter += entry->vmem_majflt;
-                       pse->vmem_majflt = entry->vmem_majflt;
-               }
-               else
-               {
-                       if (entry->vmem_minflt_counter < pse->vmem_minflt_counter)
-                       {
-                               pse->vmem_minflt = entry->vmem_minflt_counter
-                                       + (ULONG_MAX - pse->vmem_minflt_counter);
-                       }
-                       else
-                       {
-                               pse->vmem_minflt = entry->vmem_minflt_counter - pse->vmem_minflt_counter;
-                       }
-                       pse->vmem_minflt_counter = entry->vmem_minflt_counter;
-
-                       if (entry->vmem_majflt_counter < pse->vmem_majflt_counter)
-                       {
-                               pse->vmem_majflt = entry->vmem_majflt_counter
-                                       + (ULONG_MAX - pse->vmem_majflt_counter);
-                       }
-                       else
-                       {
-                               pse->vmem_majflt = entry->vmem_majflt_counter - pse->vmem_majflt_counter;
-                       }
-                       pse->vmem_majflt_counter = entry->vmem_majflt_counter;
-               }
-
-               ps->vmem_minflt_counter += pse->vmem_minflt;
-               ps->vmem_majflt_counter += pse->vmem_majflt;
-
-               if ((entry->cpu_user_counter == 0)
-                               && (entry->cpu_system_counter == 0))
-               {
-                       pse->cpu_user_counter += entry->cpu_user;
-                       pse->cpu_user = entry->cpu_user;
-
-                       pse->cpu_system_counter += entry->cpu_system;
-                       pse->cpu_system = entry->cpu_system;
-               }
-               else
-               {
-                       if (entry->cpu_user_counter < pse->cpu_user_counter)
-                       {
-                               pse->cpu_user = entry->cpu_user_counter
-                                       + (ULONG_MAX - pse->cpu_user_counter);
-                       }
-                       else
-                       {
-                               pse->cpu_user = entry->cpu_user_counter - pse->cpu_user_counter;
-                       }
-                       pse->cpu_user_counter = entry->cpu_user_counter;
-
-                       if (entry->cpu_system_counter < pse->cpu_system_counter)
-                       {
-                               pse->cpu_system = entry->cpu_system_counter
-                                       + (ULONG_MAX - pse->cpu_system_counter);
-                       }
-                       else
-                       {
-                               pse->cpu_system = entry->cpu_system_counter - pse->cpu_system_counter;
-                       }
-                       pse->cpu_system_counter = entry->cpu_system_counter;
-               }
-
-               ps->cpu_user_counter   += pse->cpu_user;
-               ps->cpu_system_counter += pse->cpu_system;
+               want_init = (entry->vmem_minflt_counter == 0)
+                               && (entry->vmem_majflt_counter == 0);
+               ps_update_counter (want_init,
+                               &ps->vmem_minflt_counter,
+                               &pse->vmem_minflt_counter, &pse->vmem_minflt,
+                               entry->vmem_minflt_counter, entry->vmem_minflt);
+               ps_update_counter (want_init,
+                               &ps->vmem_majflt_counter,
+                               &pse->vmem_majflt_counter, &pse->vmem_majflt,
+                               entry->vmem_majflt_counter, entry->vmem_majflt);
+
+               want_init = (entry->cpu_user_counter == 0)
+                               && (entry->cpu_system_counter == 0);
+               ps_update_counter (want_init,
+                               &ps->cpu_user_counter,
+                               &pse->cpu_user_counter, &pse->cpu_user,
+                               entry->cpu_user_counter, entry->cpu_user);
+               ps_update_counter (want_init,
+                               &ps->cpu_system_counter,
+                               &pse->cpu_system_counter, &pse->cpu_system,
+                               entry->cpu_system_counter, entry->cpu_system);
        }
 }