lavu/mem: un-inline av_size_mult()

There seems to be no compelling reason for it to be inline.

1 files changed, 18 insertions, 0 deletions

diff --git a/libavutil/mem.c b/libavutil/mem.c
index a52d33d4a6..063635fb22 100644
--- a/libavutil/mem.c
+++ b/libavutil/mem.c
@@ -547,3 +547,21 @@ void av_fast_mallocz(void *ptr, unsigned int *size, size_t min_size)
 {
     fast_malloc(ptr, size, min_size, 1);
 }
+
+int av_size_mult(size_t a, size_t b, size_t *r)
+{
+    size_t t;
+
+#if (!defined(__INTEL_COMPILER) && AV_GCC_VERSION_AT_LEAST(5,1)) || AV_HAS_BUILTIN(__builtin_mul_overflow)
+    if (__builtin_mul_overflow(a, b, &t))
+        return AVERROR(EINVAL);
+#else
+    t = a * b;
+    /* Hack inspired from glibc: don't try the division if nelem and elsize
+     * are both less than sqrt(SIZE_MAX). */
+    if ((a | b) >= ((size_t)1 << (sizeof(size_t) * 4)) && a && t / a != b)
+        return AVERROR(EINVAL);
+#endif
+    *r = t;
+    return 0;
+}