Changeset 527 for trunk/kernel/devices

Timestamp:

Aug 30, 2018, 10:26:27 PM (6 years ago)

Author:

viala@…

Message:

Rewrite if-then-else return function into switch case.

For safety reason and performance:

1) Safety: GCC complain with a warning if you forgot an enum variant.
2) code-gen just outperform naive if-then-else.

Location:

trunk/kernel/devices

Files:

• dev_txt.c (modified) (1 diff)
• dev_txt.h (modified) (2 diffs)

trunk/kernel/devices/dev_txt.c

@@ -49 +49 @@
 
 ////////////////////////////////////////
-char * dev_txt_type_str( uint32_t type )
-{
-    if     ( type == TXT_SYNC_WRITE ) return "TXT_SYNC_WRITE";
-    else if( type == TXT_READ       ) return "TXT_READ";
-    else if( type == TXT_WRITE      ) return "TXT_WRITE";
-    else                              return "undefined"; 
+const char * dev_txt_type_str( dev_txt_cmd_t type )
+{
+  switch (type) {
+    case (TXT_SYNC_WRITE): return "TXT_SYNC_WRITE";
+    case (TXT_READ):       return "TXT_READ";
+    case (TXT_WRITE):      return "TXT_WRITE";
+    default:               return "undefined";
+  }
 }
 

trunk/kernel/devices/dev_txt.h

@@ -78 +78 @@
  *****************************************************************************************/
 
-enum
+typedef enum
 {
     TXT_READ       = 0,
     TXT_WRITE      = 1,
     TXT_SYNC_WRITE = 2,
-};
+} dev_txt_cmd_t;
 
 typedef struct txt_command_s
@@ -113 +113 @@
  * @ type     : command type (TXT_READ / TXT_WRITE / TXT_SYNC_WRITE)
  *****************************************************************************************/
-char * dev_txt_type_str( uint32_t type );
+const char * dev_txt_type_str( dev_txt_cmd_t type );
 
 /******************************************************************************************