[datapipe] Make submode_repr() functions generally available

Debugging bitmapped submode changes is made more difficult than
what it needs to be due to bitmap-to-human-readable-string
helper functions being available in modetransition module only.

Move the helper functionality to datapipe module and make it
available for all mce modules.

Signed-off-by: Simo Piiroinen <simo.piiroinen@jollamobile.com>

datapipe.c

@@ -939,6 +939,75 @@ void mce_datapipe_quit(void)
 	free_datapipe(&proximity_blank_pipe);
 }
 
+/** Convert submode_t bitmap changes to human readable string
+ *
+ * @param prev  submode_t bitmap changed from
+ * @param curr  submode_t bitmap changed to
+ *
+ * @return human readable representation of submode
+ */
+const char *submode_change_repr(submode_t prev, submode_t curr)
+{
+	static const struct {
+		submode_t bit; const char *name;
+	} lut[] = {
+		{ MCE_INVALID_SUBMODE,          "INVALID"          },
+		{ MCE_TKLOCK_SUBMODE,           "TKLOCK"           },
+		{ MCE_EVEATER_SUBMODE,          "EVEATER"          },
+		{ MCE_BOOTUP_SUBMODE,           "BOOTUP"           },
+		{ MCE_TRANSITION_SUBMODE,       "TRANSITION"       },
+		{ MCE_AUTORELOCK_SUBMODE,       "AUTORELOCK"       },
+		{ MCE_VISUAL_TKLOCK_SUBMODE,    "VISUAL_TKLOCK"    },
+		{ MCE_POCKET_SUBMODE,           "POCKET"           },
+		{ MCE_PROXIMITY_TKLOCK_SUBMODE, "PROXIMITY_TKLOCK" },
+		{ MCE_MALF_SUBMODE,             "MALF"             },
+		{ 0,0 }
+	};
+
+	static char buff[128];
+	char *pos = buff;
+	char *end = buff + sizeof buff - 1;
+
+	auto inline void add(const char *str)
+	{
+		while( pos < end && *str )
+			*pos++ = *str++;
+	}
+
+	for( int i = 0; lut[i].name; ++i ) {
+		const char *tag = 0;
+
+		if( curr & lut[i].bit ) {
+			tag = (prev & lut[i].bit) ? "" : "+";
+		}
+		else if( prev & lut[i].bit ) {
+			tag = "-";
+		}
+
+		if( tag ) {
+			if( pos> buff ) add(" ");
+			add(tag);
+			add(lut[i].name);
+		}
+	}
+	if( pos == buff ) {
+		add("NONE");
+	}
+	*pos = 0;
+	return buff;
+}
+
+/** Convert submode_t bitmap to human readable string
+ *
+ * @param submode submode_t bitmap
+ *
+ * @return human readable representation of submode
+ */
+const char *submode_repr(submode_t submode)
+{
+  return submode_change_repr(submode, submode);
+}
+
 /** Convert system_state_t enum to human readable string
  *
  * @param state system_state_t enumeration value

mce.h

@@ -170,6 +170,9 @@ const char *alarm_state_repr(alarm_ui_state_t state);
 /** System sub-modes; several of these can be active at once */
 typedef gint submode_t;
 
+const char *submode_change_repr(submode_t prev, submode_t curr);
+const char *submode_repr(submode_t submode);
+
 /** Submode invalid */
 #define MCE_INVALID_SUBMODE		(1 << 31)
 

modetransition.c

@@ -33,51 +33,6 @@
 
 #include <glib/gstdio.h>
 
-/** Submode change in human readable form
- */
-static char *mce_submode_change(const submode_t prev, const submode_t curr)
-{
-	static const struct {
-		submode_t bit; const char *name;
-	} lut[] = {
-		{ MCE_INVALID_SUBMODE,          "INVALID"          },
-		{ MCE_TKLOCK_SUBMODE,           "TKLOCK"           },
-		{ MCE_EVEATER_SUBMODE,          "EVEATER"          },
-		{ MCE_BOOTUP_SUBMODE,           "BOOTUP"           },
-		{ MCE_TRANSITION_SUBMODE,       "TRANSITION"       },
-		{ MCE_AUTORELOCK_SUBMODE,       "AUTORELOCK"       },
-		{ MCE_VISUAL_TKLOCK_SUBMODE,    "VISUAL_TKLOCK"    },
-		{ MCE_POCKET_SUBMODE,           "POCKET"           },
-		{ MCE_PROXIMITY_TKLOCK_SUBMODE, "PROXIMITY_TKLOCK" },
-		{ MCE_MALF_SUBMODE,             "MALF"             },
-		{ 0,0 }
-	};
-
-	char temp[256], *pos = temp;
-
-	*pos = 0;
-	for( int i = 0; lut[i].name; ++i ) {
-		const char *tag = 0;
-
-		if( curr & lut[i].bit ) {
-			tag = (prev & lut[i].bit) ? "" : "+";
-		}
-		else if( prev & lut[i].bit ) {
-			tag = "-";
-		}
-		if( tag ) {
-			if( pos > temp ) *pos++ = ' ';
-			pos = stpcpy(pos, tag);
-			pos = stpcpy(pos, lut[i].name);
-		}
-	}
-	if( pos == temp ) {
-		pos = stpcpy(pos, "NORMAL");
-	}
-	*pos = 0;
-	return strdup(temp);
-}
-
 /**
  * Set the MCE submode flags
  *
@@ -91,11 +46,8 @@ static gboolean mce_set_submode_int32(const submode_t submode)
 	if (old_submode == submode)
 		goto EXIT;
 
-	if( mce_log_p(LL_NOTICE) ) {
-		char *delta = mce_submode_change(old_submode, submode);
-		mce_log(LL_NOTICE, "submode change: %s", delta ?: "???");
-		free(delta);
-	}
+	mce_log(LL_NOTICE, "submode change: %s",
+		submode_change_repr(old_submode, submode));
 
 	execute_datapipe(&submode_pipe, GINT_TO_POINTER(submode),
 			 USE_INDATA, CACHE_INDATA);