if self.ctx == 0:
raise DigestError("Unable to create digest context")
if libcrypto.EVP_DigestSignInit(self.ctx,pointer(pctx),d,None,self.key) <= 0:
if self.ctx == 0:
raise DigestError("Unable to create digest context")
if libcrypto.EVP_DigestSignInit(self.ctx,pointer(pctx),d,None,self.key) <= 0: