cleanup, always using realloc now, added proper error messages.

Author: itzpr3d4t0r

src_c/alphablit.c

@@ -597,9 +597,9 @@ pg_cached_blitcopy(SDL_Surface *src, SDL_Surface *dst,
     for (i = 0; i < destinations->size; i++) {
         CachedBlitDest *item = &destinations->sequence[i];
 
-        const Py_ssize_t src_pitch = item->w * sizeof(Uint32);
-        const Py_ssize_t src_skip = src->pitch / 4;
-        const Py_ssize_t dst_skip = dst->pitch / 4;
+        const int src_pitch = item->w * sizeof(Uint32);
+        const int src_skip = src->pitch / 4;
+        const int dst_skip = dst->pitch / 4;
 
         Uint32 *srcp32 = (Uint32 *)src->pixels + item->x + item->y * src_skip;
         Uint32 *dstp32 = item->pixels;
@@ -616,24 +616,15 @@ int
 SoftCachedBlitPyGame(SDL_Surface *src, SDL_Surface *dst, int blend_flags,
                      BlitSequence *destinations)
 {
-    int okay;
-    int src_locked;
-    int dst_locked;
-    SDL_BlendMode src_blend;
+    int okay = 1;
+    int src_locked = 0, dst_locked = 0;
 
-    /* Everything is okay at the beginning...  */
-    okay = 1;
-
-    /* Lock the destination if it's in hardware */
-    dst_locked = 0;
     if (SDL_MUSTLOCK(dst)) {
         if (SDL_LockSurface(dst) < 0)
             okay = 0;
         else
             dst_locked = 1;
     }
-    /* Lock the source if it's in hardware */
-    src_locked = 0;
     if (SDL_MUSTLOCK(src)) {
         if (SDL_LockSurface(src) < 0)
             okay = 0;
@@ -642,6 +633,7 @@ SoftCachedBlitPyGame(SDL_Surface *src, SDL_Surface *dst, int blend_flags,
     }
 
     if (okay) {
+        SDL_BlendMode src_blend;
         switch (blend_flags) {
             case 0:
                 /* unhandled cases */
@@ -661,13 +653,12 @@ SoftCachedBlitPyGame(SDL_Surface *src, SDL_Surface *dst, int blend_flags,
         }
     }
 
-    /* We need to unlock the surfaces if they're locked */
     if (dst_locked)
         SDL_UnlockSurface(dst);
     if (src_locked)
         SDL_UnlockSurface(src);
-    /* Blit is done! */
-    return (okay ? 0 : -1);
+
+    return okay ? 0 : -1;
 }
 
 /* --------------------------------------------------------- */

src_c/surface.c

@@ -2157,6 +2157,8 @@ surf_blits(pgSurfaceObject *self, PyObject *args, PyObject *keywds)
 #define FBLITS_ERR_CACHE_RLE_NOT_SUPPORTED 16
 #define FBLITS_ERR_FLAG_NOT_SUPPORTED 17
 #define FBLITS_ERR_NO_MEMORY 18
+#define FBLITS_ERR_INVALID_SEQUENCE_LENGTH 19
+#define FBLITS_ERR_INVALID_DESTINATION 20
 
 int
 _surf_fblits_item_check_and_blit(pgSurfaceObject *self, PyObject *item,
@@ -2255,20 +2257,10 @@ _surf_fblits_cached_item_check_and_blit(pgSurfaceObject *self, PyObject *item,
         return FBLITS_ERR_CACHE_RLE_NOT_SUPPORTED;
     }
 
-    /* manage destinations memory allocation or reallocation */
+    /* manage destinations memory */
     Py_ssize_t new_size = PyList_GET_SIZE(pos_list);
-    if (destinations->sequence == NULL) {
-        destinations->sequence =
-            (CachedBlitDest *)malloc(new_size * sizeof(CachedBlitDest));
-        destinations->size = destinations->alloc_size = new_size;
-        if (!destinations->sequence) {
-            return FBLITS_ERR_NO_MEMORY;
-        }
-    }
-    else if (new_size > 0 && new_size <= destinations->alloc_size) {
-        destinations->size = new_size;
-    }
-    else if (new_size > destinations->alloc_size) {
+    if (new_size > destinations->alloc_size) {
+        /* no realloc as we don't care about the previous destinations */
         destinations->sequence = (CachedBlitDest *)realloc(
             destinations->sequence, new_size * sizeof(CachedBlitDest));
 
@@ -2277,8 +2269,13 @@ _surf_fblits_cached_item_check_and_blit(pgSurfaceObject *self, PyObject *item,
 
         destinations->size = destinations->alloc_size = new_size;
     }
+    else if (new_size > 0 && new_size <= destinations->alloc_size) {
+        destinations->size = new_size;
+    }
     else {
-        return FBLITS_ERR_INCORRECT_ARGS_NUM;
+        if (new_size == 0)
+            return 0;
+        return FBLITS_ERR_INVALID_SEQUENCE_LENGTH;
     }
 
     /* load destinations */
@@ -2294,7 +2291,7 @@ _surf_fblits_cached_item_check_and_blit(pgSurfaceObject *self, PyObject *item,
 
         if (!pg_IntFromObj(PyTuple_GET_ITEM(tup, 0), &x) ||
             !pg_IntFromObj(PyTuple_GET_ITEM(tup, 1), &y)) {
-            return FBLITS_ERR_INCORRECT_ARGS_NUM;
+            return FBLITS_ERR_INVALID_DESTINATION;
         }
 
         if (x < -src->w || x > dst->w || y < -src->h || y > dst->h)
@@ -2367,6 +2364,9 @@ _surf_fblits_cached_item_check_and_blit(pgSurfaceObject *self, PyObject *item,
         pgSurface_Unprep(self);
     pgSurface_Unprep((pgSurfaceObject *)src_surf);
 
+    if (error == -1)
+        error = BLITS_ERR_BLIT_FAIL;
+
     return error;
 }
 
@@ -2518,6 +2518,12 @@ surf_fblits(pgSurfaceObject *self, PyObject *const *args, Py_ssize_t nargs)
                          "supported for this operation");
         case FBLITS_ERR_NO_MEMORY:
             return RAISE(PyExc_MemoryError, "No memory available");
+        case FBLITS_ERR_INVALID_SEQUENCE_LENGTH:
+            return RAISE(PyExc_ValueError,
+                         "Invalid sequence length for cached blit");
+        case FBLITS_ERR_INVALID_DESTINATION:
+            return RAISE(PyExc_TypeError,
+                         "Invalid destination position for cached blit");
     }
     return RAISE(PyExc_TypeError, "Unknown error");
 }