[FFmpeg-devel] [PATCH 1/5] lavu: add av_dynarray_alloc_elem().

[Clément Bœsch]

---
 libavutil/mem.c     | 19 +++++++++++++++++++
 libavutil/mem.h     | 13 +++++++++++++
 libavutil/version.h |  2 +-
 3 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/libavutil/mem.c b/libavutil/mem.c
index 860c011..835c73a 100644
--- a/libavutil/mem.c
+++ b/libavutil/mem.c
@@ -250,6 +250,25 @@ void av_dynarray_add(void *tab_ptr, int *nb_ptr, void *elem)
     *nb_ptr = nb;
 }
 
+void *av_dynarray_alloc_elem(void **tab_ptr, int *nb_ptr, size_t elem_size)
+{
+    int nb = *nb_ptr;
+    uint8_t *tab = *tab_ptr;
+
+    if ((nb & (nb - 1)) == 0) {
+        int nb_alloc = nb == 0 ? 1 : nb * 2;
+        tab = av_realloc_f(tab, nb_alloc, elem_size);
+        if (!tab)
+            return NULL;
+        *tab_ptr = tab;
+    }
+    *nb_ptr = nb + 1;
+#if CONFIG_MEMORY_POISONING
+    memset(tab + nb*elem_size, 0x2a, elem_size);
+#endif
+    return tab + nb*elem_size;
+}
+
 static void fill16(uint8_t *dst, int len)
 {
     uint32_t v = AV_RN16(dst - 2);
diff --git a/libavutil/mem.h b/libavutil/mem.h
index ced9453..64d86ff 100644
--- a/libavutil/mem.h
+++ b/libavutil/mem.h
@@ -198,6 +198,19 @@ void av_freep(void *ptr);
 void av_dynarray_add(void *tab_ptr, int *nb_ptr, void *elem);
 
 /**
+ * Allocate an element of size elem_size to a dynamic array.
+ *
+ * @param tab_ptr   Pointer to the array.
+ * @param nb_ptr    Pointer to the number of elements in the array.
+ * @param elem_size Size of the elements in the array.
+ * @return          Pointer to the elem_size allocated space at the end of the
+ *                  array, or NULL in case of memory error
+ *
+ * @note this function is not compatible with av_dynarray_add
+ */
+void *av_dynarray_alloc_elem(void **tab_ptr, int *nb_ptr, size_t elem_size);
+
+/**
  * Multiply two size_t values checking for overflow.
  * @return  0 if success, AVERROR(EINVAL) if overflow.
  */
diff --git a/libavutil/version.h b/libavutil/version.h
index 6531397..e46e97c 100644
--- a/libavutil/version.h
+++ b/libavutil/version.h
@@ -75,7 +75,7 @@
  */
 
 #define LIBAVUTIL_VERSION_MAJOR  52
-#define LIBAVUTIL_VERSION_MINOR  26
+#define LIBAVUTIL_VERSION_MINOR  27
 #define LIBAVUTIL_VERSION_MICRO 100
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \
-- 
1.8.2.1