Pass in the vector insertion point as a pointer

2 files changed, 5 insertions, 3 deletions

diff --git a/Alc/helpers.c b/Alc/helpers.c
index 2fbb588b..97f7988e 100644
--- a/Alc/helpers.c
+++ b/Alc/helpers.c
@@ -796,14 +796,16 @@ ALboolean vector_resize(void *ptr, size_t base_size, size_t obj_count, size_t ob
     return AL_TRUE;
 }
 
-ALboolean vector_insert(void *ptr, size_t base_size, size_t obj_size, ptrdiff_t ins_elem, const void *datstart, const void *datend)
+ALboolean vector_insert(void *ptr, size_t base_size, size_t obj_size, void *ins_pos, const void *datstart, const void *datend)
 {
     vector_ *vecptr = ptr;
     if(datstart != datend)
     {
+        ptrdiff_t ins_elem = ((char*)ins_pos - ((char*)(*vecptr) + base_size)) / obj_size;
         ptrdiff_t numins = ((const char*)datend - (const char*)datstart) / obj_size;
         if(!vector_reserve(vecptr, base_size, VECTOR_SIZE(*vecptr)+numins, obj_size, AL_TRUE))
             return AL_FALSE;
+        /* NOTE: ins_pos may have been invalidated if *vecptr moved. Use ins_elem instead. */
         if(ins_elem < (*vecptr)->Size)
         {
             memmove((char*)(*vecptr) + base_size + ((ins_elem+numins)*obj_size),
diff --git a/Alc/vector.h b/Alc/vector.h
index 7f3d769c..d12b8ad1 100644
--- a/Alc/vector.h
+++ b/Alc/vector.h
@@ -35,8 +35,8 @@ ALboolean vector_resize(void *ptr, size_t base_size, size_t obj_count, size_t ob
 #define VECTOR_ITER_BEGIN(_x) ((_x)->Data)
 #define VECTOR_ITER_END(_x)   ((_x)->Data + VECTOR_SIZE((_x)))
 
-ALboolean vector_insert(void *ptr, size_t base_size, size_t obj_size, ptrdiff_t ins_elem, const void *datstart, const void *datend);
-#define VECTOR_INSERT(_x, _i, _s, _e) (vector_insert(&(_x), sizeof(*(_x)), sizeof((_x)->Data[0]), (_i)-VECTOR_ITER_BEGIN(_x), (_s), (_e)))
+ALboolean vector_insert(void *ptr, size_t base_size, size_t obj_size, void *ins_pos, const void *datstart, const void *datend);
+#define VECTOR_INSERT(_x, _i, _s, _e) (vector_insert(&(_x), sizeof(*(_x)), sizeof((_x)->Data[0]), (_i), (_s), (_e)))
 
 #define VECTOR_PUSH_BACK(_x, _obj) (vector_reserve(&(_x), sizeof(*(_x)), VECTOR_SIZE(_x)+1, sizeof((_x)->Data[0]), AL_FALSE) && \
                                     (((_x)->Data[(_x)->Size++] = (_obj)),AL_TRUE))