Cache the address of the mode struct in the Image header

Author: wiredfool

src/libImaging/Arrow.c

@@ -62,7 +62,6 @@ image_band_json(Imaging im) {
     // Bands can be 4 bands * 2 characters each
     int len = strlen(format) + 8 + 1;
     int err;
-    ModeData *modedata = getModeData(im->mode);
 
     json = calloc(1, len);
 
@@ -74,10 +73,10 @@ image_band_json(Imaging im) {
         json,
         len,
         format,
-        modedata->band_names[0],
-        modedata->band_names[1],
-        modedata->band_names[2],
-        modedata->band_names[3]
+        im->modedata->band_names[0],
+        im->modedata->band_names[1],
+        im->modedata->band_names[2],
+        im->modedata->band_names[3]
     );
     if (err < 0) {
         return NULL;
@@ -99,7 +98,7 @@ single_band_json(Imaging im) {
         return NULL;
     }
 
-    err = PyOS_snprintf(json, len, format, getModeData(im->mode)->band_names[0]);
+    err = PyOS_snprintf(json, len, format, im->modedata->band_names[0]);
     if (err < 0) {
         return NULL;
     }
@@ -189,9 +188,8 @@ int
 export_imaging_schema(Imaging im, struct ArrowSchema *schema) {
     int retval = 0;
     char *band_json;
-    ModeData *modedata = getModeData(im->mode);
 
-    if (strcmp(modedata->arrow_band_format, "") == 0) {
+    if (strcmp(im->modedata->arrow_band_format, "") == 0) {
         return IMAGING_ARROW_INCOMPATIBLE_MODE;
     }
 
@@ -200,10 +198,10 @@ export_imaging_schema(Imaging im, struct ArrowSchema *schema) {
         return IMAGING_ARROW_MEMORY_LAYOUT;
     }
 
-    modedata = getModeData(im->mode);
-
     if (im->bands == 1) {
-        retval = export_named_type(schema, modedata->arrow_band_format, modedata->band_names[0]);
+        retval = export_named_type(schema,
+                                   im->modedata->arrow_band_format,
+                                   im->modedata->band_names[0]);
         if (retval != 0) {
             return retval;
         }
@@ -225,7 +223,7 @@ export_imaging_schema(Imaging im, struct ArrowSchema *schema) {
     schema->children = calloc(1, sizeof(struct ArrowSchema *));
     schema->children[0] = (struct ArrowSchema *)calloc(1, sizeof(struct ArrowSchema));
     retval = export_named_type(
-        schema->children[0], modedata->arrow_band_format, modedata->name
+        schema->children[0], im->modedata->arrow_band_format, im->modedata->name
     );
     if (retval != 0) {
         free(schema->children[0]);
@@ -409,7 +407,7 @@ export_fixed_pixel_array(Imaging im, struct ArrowArray *array) {
 
 int
 export_imaging_array(Imaging im, struct ArrowArray *array) {
-    if (strcmp(getModeData(im->mode)->arrow_band_format, "") == 0) {
+    if (strcmp(im->modedata->arrow_band_format, "") == 0) {
         return IMAGING_ARROW_INCOMPATIBLE_MODE;
     }
 

src/libImaging/Imaging.h

@@ -80,6 +80,7 @@ typedef struct {
 struct ImagingMemoryInstance {
     /* Format */
     ModeID mode; /* Image mode (IMAGING_MODE_*) */
+    const ModeData *modedata; /* mode data struct */
     int type;    /* Data type (IMAGING_TYPE_*) */
     int depth;   /* Depth (ignored in this version) */
     int bands;   /* Number of bands (1, 2, 3, or 4) */

src/libImaging/Storage.c

@@ -60,6 +60,7 @@ ImagingNewPrologueSubtype(const ModeID mode, int xsize, int ysize, int size) {
     im->ysize = ysize;
     im->refcount = 1;
     im->type = IMAGING_TYPE_UINT8;
+    im->modedata = getModeData(mode);
 
     if (mode == IMAGING_MODE_1) {
         /* 1-bit images */
@@ -635,7 +636,6 @@ ImagingNewArrow(
     if (!im) {
         return NULL;
     }
-    ModeData *modedata = getModeData(mode);
 
     int64_t pixels = (int64_t)xsize * (int64_t)ysize;
 
@@ -646,7 +646,7 @@ ImagingNewArrow(
           && im->pixelsize == 4             // 4xchar* storage
           && im->bands >= 2)                // INT32 into any INT32 Storage mode
          ||                                 // (()||()) &&
-         (strcmp(schema->format, modedata->arrow_band_format) == 0  // same mode
+         (strcmp(schema->format, im->modedata->arrow_band_format) == 0  // same mode
           && im->bands == 1))                                 // Single band match
         && pixels == external_array->length) {
         // one arrow element per, and it matches a pixelsize*char
@@ -660,7 +660,7 @@ ImagingNewArrow(
         && schema->n_children > 0            // make sure schema is well formed.
         && schema->children                  // make sure schema is well formed
         && strcmp(schema->children[0]->format, "C") == 0  // Expected format
-        && strcmp(modedata->arrow_band_format, "C") == 0  // Expected Format
+        && strcmp(im->modedata->arrow_band_format, "C") == 0  // Expected Format
         && pixels == external_array->length               // expected length
         && external_array->n_children == 1                // array is well formed
         && external_array->children                       // array is well formed
@@ -674,7 +674,7 @@ ImagingNewArrow(
     if (strcmp(schema->format, "C") == 0            // uint8
         && im->pixelsize == 4                       // storage as 32 bpc
         && schema->n_children == 0                  // make sure schema is well formed.
-        && strcmp(modedata->arrow_band_format, "C") == 0  // expected format
+        && strcmp(im->modedata->arrow_band_format, "C") == 0  // expected format
         && 4 * pixels == external_array->length) {  // expected length
         // single flat array, interleaved storage.
         if (ImagingBorrowArrow(im, external_array, 1, array_capsule)) {