From 041c4f41df5d143fa4612b3432df6b31a685a9e9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=A9r=C3=A9my=20Zurcher?= <jeremy@asynk.ch>
Date: Thu, 13 Jun 2013 14:59:26 +0200
Subject: [PATCH] add EAPI Eina_List* eina_list_reduce(Eina_List *list,
 Eina_Reduce_Cb func, void *acc)

- apply the reduce function on the list nodes
- typedef void (*Eina_Reduce_Cb)(const void *data, void *acc)
---
 src/lib/eina/eina_list.c        | 20 ++++++++++++++++++++
 src/lib/eina/eina_list.h        | 13 +++++++++++++
 src/lib/eina/eina_types.h       | 12 ++++++++++++
 src/tests/eina/eina_test_list.c | 14 ++++++++++++--
 4 files changed, 57 insertions(+), 2 deletions(-)

diff --git a/src/lib/eina/eina_list.c b/src/lib/eina/eina_list.c
index 3cf7940a4b..e2cb1cde22 100644
--- a/src/lib/eina/eina_list.c
+++ b/src/lib/eina/eina_list.c
@@ -1198,6 +1198,26 @@ eina_list_map(Eina_List *list, Eina_Map_Cb func)
    return list;
 }
 
+EAPI Eina_List *
+eina_list_reduce(Eina_List *list, Eina_Reduce_Cb func, void *acc)
+{
+   const Eina_List *l;
+   void *data;
+
+   if (!list)
+     return NULL;
+
+   EINA_MAGIC_CHECK_LIST(list, NULL);
+
+   if (func == NULL)
+     return list;
+
+   EINA_LIST_FOREACH(list, l, data)
+      func(data, acc);
+
+   return list;
+}
+
 EAPI Eina_List *
 eina_list_shuffle(Eina_List *list, Eina_Random_Cb func)
 {
diff --git a/src/lib/eina/eina_list.h b/src/lib/eina/eina_list.h
index 3163031ef3..509b60a873 100644
--- a/src/lib/eina/eina_list.h
+++ b/src/lib/eina/eina_list.h
@@ -970,6 +970,19 @@ EAPI Eina_List            *eina_list_filter(Eina_List *list, Eina_Filter_Cb func
  */
 EAPI Eina_List            *eina_list_map(Eina_List *list, Eina_Map_Cb func) EINA_WARN_UNUSED_RESULT;
 
+/**
+ * @brief Apply a reduce function on all nodes of list
+ *
+ * @param list The list to reduce.
+ * @param func The reduce function to apply on nodes.
+ * @param acc The pointer to the accumulator of the reduce function.
+ * @return The same list.
+ * @since 1.8
+ *
+ * @warning @p list must be a pointer to the first element of the list.
+ */
+EAPI Eina_List            *eina_list_reduce(Eina_List *list, Eina_Reduce_Cb func, void *acc) EINA_WARN_UNUSED_RESULT;
+
 /**
  * @brief Shuffle list.
  *
diff --git a/src/lib/eina/eina_types.h b/src/lib/eina/eina_types.h
index c5e213cf11..160da8d38b 100644
--- a/src/lib/eina/eina_types.h
+++ b/src/lib/eina/eina_types.h
@@ -359,6 +359,18 @@ typedef void (*Eina_Map_Cb)(const void *data);
  */
 #define EINA_MAP_CB(function) ((Eina_Map_Cb)function)
 
+/**
+ * @typedef Eina_Reduce_Cb
+ * Function to be applied on nodes.
+ */
+typedef void (*Eina_Reduce_Cb)(const void *data, void *acc);
+
+/**
+ * @def EINA_REDUCE_CB
+ * Macro to cast to Eina_Reduce_Cb.
+ */
+#define EINA_REDUCE_CB(function) ((Eina_Reduce_Cb)function)
+
 /**
  * @typedef Eina_Random_Cb
  * Function used in shuffling functions. An integer betwen min and max
diff --git a/src/tests/eina/eina_test_list.c b/src/tests/eina/eina_test_list.c
index 45c296d56b..2e01061d73 100644
--- a/src/tests/eina/eina_test_list.c
+++ b/src/tests/eina/eina_test_list.c
@@ -506,10 +506,16 @@ static void map_cb(int *data)
    *data = *data * 3;
 }
 
-START_TEST(eina_test_filter)
+static void reduce_cb(int *data, int *acc)
+{
+   *acc += (*data * 3);
+}
+
+START_TEST(eina_test_filter_map_reduce)
 {
    int i;
    int *p;
+   int sum;
    int data[] = { 6, 9, 93, 42, 1, 7, 9, 81, 1664, 1337 };
    int result1[] = { 6, 9, 42, 1, 7, 9 };
    int result2[] = { 18, 27, 126, 3, 21, 27 };
@@ -545,6 +551,10 @@ START_TEST(eina_test_filter)
            p = eina_list_nth(l, i);
            fail_if(*p != result2[i]);
         }
+
+   l = eina_list_reduce(l, EINA_REDUCE_CB(reduce_cb), &sum);
+      fail_if(sum != 666);
+
    l = eina_list_free(l);
 
    list = eina_list_free(list);
@@ -562,5 +572,5 @@ eina_test_list(TCase *tc)
    tcase_add_test(tc, eina_test_list_split);
    tcase_add_test(tc, eina_test_shuffle);
    tcase_add_test(tc, eina_test_remove_duplicates);
-   tcase_add_test(tc, eina_test_filter);
+   tcase_add_test(tc, eina_test_filter_map_reduce);
 }