Make sure image nullness checks raise ValueErrors, not ModeErrors

Author: akx

src/libImaging/Bands.c

@@ -23,8 +23,12 @@ ImagingGetBand(Imaging imIn, int band) {
     int x, y;
 
     /* Check arguments */
-    if (!imIn || imIn->type != IMAGING_TYPE_UINT8) {
-        return (Imaging)ImagingError_NotSupportedError(NULL);
+    if (!imIn) {
+        return (Imaging)ImagingError_ValueError(NULL);
+    }
+
+    if (imIn->type != IMAGING_TYPE_UINT8) {
+        return (Imaging)ImagingError_NotSupportedError("only 8-bit images supported");
     }
 
     if (band < 0 || band >= imIn->bands) {
@@ -73,8 +77,13 @@ ImagingSplit(Imaging imIn, Imaging bands[4]) {
     int i, j, x, y;
 
     /* Check arguments */
-    if (!imIn || imIn->type != IMAGING_TYPE_UINT8) {
-        (void)ImagingError_NotSupportedError(NULL);
+    if (!imIn) {
+        (void)ImagingError_ValueError(NULL);
+        return 0;
+    }
+
+    if (imIn->type != IMAGING_TYPE_UINT8) {
+        (void)ImagingError_NotSupportedError("only 8-bit images supported");
         return 0;
     }
 
@@ -179,7 +188,7 @@ ImagingPutBand(Imaging imOut, Imaging imIn, int band) {
 
     /* Check arguments */
     if (!imIn || !imOut) {
-        return (Imaging)ImagingError_ModeError(NULL);
+        return (Imaging)ImagingError_ValueError(NULL);
     }
     if (imIn->bands != 1) {
         return (Imaging)ImagingError_ModeError("source image must have exactly 1 band");
@@ -231,6 +240,10 @@ ImagingFillBand(Imaging imOut, int band, int color) {
         return (Imaging)ImagingError_ValueError(NULL);
     }
 
+    if (!imOut) {
+        return (Imaging)ImagingError_ValueError("only 8-bit images supported");
+    }
+
     if (imOut->type != IMAGING_TYPE_UINT8) {
         return (Imaging)ImagingError_NotSupportedError("only 8-bit images supported");
     }

src/libImaging/Blend.c

@@ -23,7 +23,10 @@ ImagingBlend(Imaging imIn1, Imaging imIn2, float alpha) {
     int x, y;
 
     /* Check arguments */
-    if (!imIn1 || !imIn2 || imIn1->type != IMAGING_TYPE_UINT8 || imIn1->palette ||
+    if (!imIn1 || !imIn2) {
+        return (Imaging)ImagingError_ValueError(NULL);
+    }
+    if (imIn1->type != IMAGING_TYPE_UINT8 || imIn1->palette ||
         imIn1->mode == IMAGING_MODE_1 || imIn2->palette ||
         imIn2->mode == IMAGING_MODE_1) {
         return ImagingError_ModeError(NULL);

src/libImaging/Chops.c

@@ -68,8 +68,11 @@
 static Imaging
 create(Imaging im1, Imaging im2, const ModeID mode) {
     int xsize, ysize;
+    if (!im1 || !im2) {
+        return (Imaging)ImagingError_ValueError(NULL);
+    }
 
-    if (!im1 || !im2 || im1->type != IMAGING_TYPE_UINT8 ||
+    if (im1->type != IMAGING_TYPE_UINT8 ||
         (mode != IMAGING_MODE_UNKNOWN &&
          (im1->mode != IMAGING_MODE_1 || im2->mode != IMAGING_MODE_1))) {
         return (Imaging)ImagingError_ModeError(NULL);

src/libImaging/Convert.c

@@ -1581,7 +1581,7 @@ convert(Imaging imOut, Imaging imIn, ModeID mode, ImagingPalette palette, int di
     ImagingShuffler convert;
 
     if (!imIn) {
-        return (Imaging)ImagingError_ModeError(NULL);
+        return (Imaging)ImagingError_ValueError(NULL);
     }
 
     if (mode == IMAGING_MODE_UNKNOWN) {
@@ -1673,7 +1673,7 @@ ImagingConvertTransparent(Imaging imIn, const ModeID mode, int r, int g, int b)
     int y;
 
     if (!imIn) {
-        return (Imaging)ImagingError_ModeError(NULL);
+        return (Imaging)ImagingError_ValueError(NULL);
     }
 
     if (imIn->mode == IMAGING_MODE_RGB &&

src/libImaging/Crop.c

@@ -25,7 +25,7 @@ ImagingCrop(Imaging imIn, int sx0, int sy0, int sx1, int sy1) {
     INT32 zero = 0;
 
     if (!imIn) {
-        return (Imaging)ImagingError_ModeError(NULL);
+        return (Imaging)ImagingError_ValueError(NULL);
     }
 
     xsize = sx1 - sx0;

src/libImaging/Histo.c

@@ -65,7 +65,7 @@ ImagingGetHistogram(Imaging im, Imaging imMask, void *minmax) {
     FLOAT32 fmin, fmax, scale;
 
     if (!im) {
-        return ImagingError_ModeError(NULL);
+        return ImagingError_ValueError(NULL);
     }
 
     if (imMask) {

src/libImaging/Matrix.c

@@ -24,7 +24,7 @@ ImagingConvertMatrix(Imaging im, const ModeID mode, const float m[12]) {
 
     /* Assume there's enough data in the buffer */
     if (!im) {
-        return (Imaging)ImagingError_ModeError(NULL);
+        return (Imaging)ImagingError_ValueError(NULL);
     }
     if (im->bands != 3) {
         return (Imaging)ImagingError_ModeError("image must have exactly 3 bands");

src/libImaging/ModeFilter.c

@@ -25,7 +25,7 @@ ImagingModeFilter(Imaging im, int size) {
     int histogram[256];
 
     if (!im) {
-        return (Imaging)ImagingError_ModeError(NULL);
+        return (Imaging)ImagingError_ValueError(NULL);
     }
     if (im->bands != 1 || im->type != IMAGING_TYPE_UINT8) {
         return (Imaging)ImagingError_ModeError("image must have 8-bit data in 1 band");

src/libImaging/Negative.c

@@ -24,7 +24,7 @@ ImagingNegative(Imaging im) {
     int x, y;
 
     if (!im) {
-        return (Imaging)ImagingError_ModeError(NULL);
+        return (Imaging)ImagingError_ValueError(NULL);
     }
 
     imOut = ImagingNewDirty(im->mode, im->xsize, im->ysize);

src/libImaging/Offset.c

@@ -22,7 +22,7 @@ ImagingOffset(Imaging im, int xoffset, int yoffset) {
     Imaging imOut;
 
     if (!im) {
-        return (Imaging)ImagingError_ModeError(NULL);
+        return (Imaging)ImagingError_ValueError(NULL);
     }
 
     imOut = ImagingNewDirty(im->mode, im->xsize, im->ysize);