Set readcount to TIFF_VARIABLE for a variable number of values

python-pillow · May 28, 2022 · 40a918d · 40a918d
1 parent 0a4a772
commit 40a918d
Showing 1 changed file with 3 additions and 11 deletions.
diff --git a/src/libImaging/TiffDecode.c b/src/libImaging/TiffDecode.c
@@ -815,11 +815,11 @@ ImagingLibTiffMergeFieldInfo(
 
     // custom fields added with ImagingLibTiffMergeFieldInfo are only used for
     // decoding, ignore readcount;
-    int readcount = 1;
+    int readcount = is_var_length ? TIFF_VARIABLE : 1;
     // we support writing a single value, or a variable number of values
-    int writecount = 1;
+    int writecount = is_var_length ? TIFF_VARIABLE : 1;
     // whether the first value should encode the number of values.
-    int passcount = 0;
+    int passcount = (is_var_length && field_type != TIFF_ASCII) ? 1 : 0;
 
     TIFFFieldInfo info[] = {
         {key,
@@ -831,14 +831,6 @@ ImagingLibTiffMergeFieldInfo(
          passcount,
          "CustomField"}};
 
-    if (is_var_length) {
-        info[0].field_writecount = -1;
-    }
-
-    if (is_var_length && field_type != TIFF_ASCII) {
-        info[0].field_passcount = 1;
-    }
-
     n = sizeof(info) / sizeof(info[0]);
 
     // Test for libtiff 4.0 or later, excluding libtiff 3.9.6 and 3.9.7