initial commit

libraries/lvgl/src/misc/lv_utils.c

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+/**
+ * @file lv_utils.c
+ *
+ */
+
+/*********************
+ *      INCLUDES
+ *********************/
+#include <stddef.h>
+
+#include "lv_utils.h"
+
+/*********************
+ *      DEFINES
+ *********************/
+
+/**********************
+ *      TYPEDEFS
+ **********************/
+
+/**********************
+ *  STATIC PROTOTYPES
+ **********************/
+
+/**********************
+ *  STATIC VARIABLES
+ **********************/
+
+/**********************
+ *      MACROS
+ **********************/
+
+/**********************
+ *   GLOBAL FUNCTIONS
+ **********************/
+
+/** Searches base[0] to base[n - 1] for an item that matches *key.
+ *
+ * @note The function cmp must return negative if its first
+ *  argument (the search key) is less than its second (a table entry),
+ *  zero if equal, and positive if greater.
+ *
+ *  @note Items in the array must be in ascending order.
+ *
+ * @param key    Pointer to item being searched for
+ * @param base   Pointer to first element to search
+ * @param n      Number of elements
+ * @param size   Size of each element
+ * @param cmp    Pointer to comparison function (see #unicode_list_compare as a comparison function
+ * example)
+ *
+ * @return a pointer to a matching item, or NULL if none exists.
+ */
+void * _lv_utils_bsearch(const void * key, const void * base, uint32_t n, uint32_t size,
+                         int32_t (*cmp)(const void * pRef, const void * pElement))
+{
+    const char * middle;
+    int32_t c;
+
+    for(middle = base; n != 0;) {
+        middle += (n / 2) * size;
+        if((c = (*cmp)(key, middle)) > 0) {
+            n    = (n / 2) - ((n & 1) == 0);
+            base = (middle += size);
+        }
+        else if(c < 0) {
+            n /= 2;
+            middle = base;
+        }
+        else {
+            return (char *)middle;
+        }
+    }
+    return NULL;
+}
+
+/**********************
+ *   STATIC FUNCTIONS
+ **********************/