Add a ws_posix_compat.h header

Currently used to define ssize_t on platforms that lack it.

Fix some Windows build errors caused by moving the definition into a
separate header.

Fix some narrowing warnings on Windows x64 from changing the definition
of ssize_t from long int to int64_t.

The casts in dumpcap are ugly but necessary. The whole code needs
to be rewritten for portability, or the warnings disabled.

1 files changed, 1 insertions, 1 deletions

diff --git a/wiretap/file_wrappers.c b/wiretap/file_wrappers.c
index 337010d625..a513389648 100644
--- a/wiretap/file_wrappers.c
+++ b/wiretap/file_wrappers.c
@@ -275,7 +275,7 @@ buf_read(FILE_T state, struct wtap_reader_buf *buf)
     if (ret == 0)
         state->eof = TRUE;
     state->raw_pos += ret;
-    buf->avail += ret;
+    buf->avail += (guint)ret;
     return 0;
 }