openssl: fix compile-time warning in Curl_ossl_check_cxn()

... introduced in curl-7_48_0-293-g2968c83:

Error: COMPILER_WARNING:
lib/vtls/openssl.c: scope_hint: In function ‘Curl_ossl_check_cxn’
lib/vtls/openssl.c:767:15: warning: conversion to ‘int’ from ‘ssize_t’
may alter its value [-Wconversion]

diff --git a/lib/vtls/openssl.c b/lib/vtls/openssl.c
index af3c502a7b91552ba774eea6f26b6d85d7e30613..6b70c0ccc26bf697509d3d82388563eda58d88de 100644 (file)
--- a/lib/vtls/openssl.c
+++ b/lib/vtls/openssl.c
@@ -763,7 +763,7 @@ int Curl_ossl_check_cxn(struct connectdata *conn)
      recv MSG_PEEK instead. Bug #795 */
 #ifdef MSG_PEEK
   char buf;
-  int nread;
+  ssize_t nread;
   nread = recv((RECV_TYPE_ARG1)conn->sock[FIRSTSOCKET], (RECV_TYPE_ARG2)&buf,
                (RECV_TYPE_ARG3)1, (RECV_TYPE_ARG4)MSG_PEEK);
   if(nread == 0)