leptonica: serialization tweaks, memory handling

ocrmypdf/leptonica.py

@@ -19,7 +19,6 @@ from .lib._leptonica import ffi
 from functools import lru_cache
 
 lept = ffi.dlopen(find_library('lept'))
-libc = ffi.dlopen(None)
 
 logger = logging.getLogger(__name__)
 
@@ -120,6 +119,7 @@ class Pix:
 
         char_data = ffi.cast('char *', data[0])
         data_bytes = ffi.buffer(char_data, size[0])[:]
+        lept.lept_free(char_data)
         return dict(data=data_bytes)
 
     def __setstate__(self, state):

ocrmypdf/lib/compile_leptonica.py

@@ -61,7 +61,10 @@ l_int32 * makePixelSumTab8 ( void );
 
 PIX * pixDeserializeFromMemory ( const l_uint32 *data, size_t nbytes );
 l_int32 pixSerializeToMemory ( PIX *pixs, l_uint32 **pdata, size_t *pnbytes );
+
+void lept_free(void *ptr);
 """)
 
+
 if __name__ == '__main__':
     ffi.compile()