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.

CMakeLists.txt

@@ -3432,6 +3432,7 @@ set(SHARK_PUBLIC_HEADERS
 	include/ws_compiler_tests.h
 	include/ws_diag_control.h
 	include/ws_log_defs.h
+	include/ws_posix_compat.h
 	include/ws_symbol_export.h
 	include/wireshark.h
 	${CMAKE_BINARY_DIR}/ws_version.h

cmakeconfig.h.in

@@ -306,10 +306,6 @@
 /* Define to 1 if the 'ssize_t' type exists. */
 #cmakedefine HAVE_SSIZE_T 1
 
-#ifndef HAVE_SSIZE_T
-#  define ssize_t long int
-#endif
-
 #if defined(_MSC_VER)
 #  define strncasecmp strnicmp
 #  define popen       _popen

doc/plugins.example/CMakeLists.txt

@@ -7,7 +7,7 @@
 # SPDX-License-Identifier: GPL-2.0-or-later
 #
 
-cmake_minimum_required(VERSION 3.1)
+cmake_minimum_required(VERSION 3.12)
 cmake_policy(SET CMP0048 NEW)
 
 project(Hello VERSION 0.0.1 DESCRIPTION "Wireshark Hello Plugin" LANGUAGES C)
@@ -18,12 +18,18 @@ if(NOT Wireshark_PLUGINS_ENABLED)
 	message(WARNING "Wireshark was compiled without support for plugins")
 endif()
 
+include(CheckTypeSize)
+check_type_size("ssize_t" SSIZE_T)
+
 set(CMAKE_C_VISIBILITY_PRESET hidden)
 if (CMAKE_COMPILER_IS_GNUCC)
     set(CMAKE_C_FLAGS  "-Wall -Wextra ${CMAKE_C_FLAGS}")
 endif()
 
-add_definitions(-DVERSION=\"${PROJECT_VERSION}\")
+add_compile_definitions(
+	VERSION=\"${PROJECT_VERSION}\"
+	$<$<BOOL:${HAVE_SSIZE_T}>:HAVE_SSIZE_T>
+)
 
 add_library(hello MODULE hello.c)
 set_target_properties(hello PROPERTIES PREFIX "" DEFINE_SYMBOL "")

dumpcap.c

@@ -1260,7 +1260,7 @@ static void *cap_thread_read(void *arg)
                        break;
                    }
                } else {
-                   bytes_read += b;
+                   bytes_read += (DWORD)b;
                }
            }
 #ifdef _WIN32
@@ -1485,7 +1485,11 @@ cap_pipe_read_data_bytes(capture_src *pcap_src, char *errmsg, size_t errmsgl)
                 }
                 return -1;
             }
+#ifdef _WIN32
+            bytes_read += (DWORD)b;
+#else
             bytes_read += b;
+#endif
         }
     }
     pcap_src->cap_pipe_bytes_read += bytes_read;
@@ -2317,7 +2321,11 @@ pcap_pipe_dispatch(loop_data *ld, capture_src *pcap_src, char *errmsg, size_t er
                     result = PD_PIPE_ERR;
                 break;
             }
+#ifdef _WIN32
+            pcap_src->cap_pipe_bytes_read += (DWORD)b;
+#else
             pcap_src->cap_pipe_bytes_read += b;
+#endif
         }
 #ifdef _WIN32
         else {
@@ -2374,7 +2382,11 @@ pcap_pipe_dispatch(loop_data *ld, capture_src *pcap_src, char *errmsg, size_t er
                     result = PD_PIPE_ERR;
                 break;
             }
+#ifdef _WIN32
+            pcap_src->cap_pipe_bytes_read += (DWORD)b;
+#else
             pcap_src->cap_pipe_bytes_read += b;
+#endif
         }
 #ifdef _WIN32
         else {

include/wireshark.h

@@ -43,6 +43,7 @@
 #include <ws_attributes.h>
 #include <ws_compiler_tests.h>
 #include <ws_diag_control.h>
+#include <ws_posix_compat.h>
 #include <ws_symbol_export.h>
 
 #include <wsutil/ws_assert.h>

include/ws_posix_compat.h

@@ -0,0 +1,33 @@
+/* ws_posix_compat.h
+ * Definitions for POSIX compatibility.
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef __POSIX_COMPAT_H__
+#define __POSIX_COMPAT_H__
+
+#include <stdint.h>
+#include <limits.h>
+
+#if !defined(SSIZE_MAX) && !defined(HAVE_SSIZE_T)
+#if defined(_WIN64)
+
+typedef int64_t ssize_t;
+
+#define SSIZE_MAX INT64_MAX
+
+#else /* !_WIN64 */
+
+typedef signed long int ssize_t;
+
+#define SSIZE_MAX LONG_MAX
+
+#endif /* _WIN64 */
+#endif /* !SSIZE_MAX && !HAVE_SSIZE_T */
+
+#endif /* __POSIX_COMPAT_H__ */

plugins/codecs/sbc/sbc.c

@@ -12,7 +12,7 @@
 
 #include "config.h"
 
-#include <glib.h>
+#include <wireshark.h>
 #include <sbc/sbc.h>
 
 #include "wsutil/codecs.h"

sync_pipe.h

@@ -18,6 +18,7 @@
 #ifndef __SYNC_PIPE_H__
 #define __SYNC_PIPE_H__
 
+#include <ws_posix_compat.h>
 
 /*
  * Maximum length of sync pipe message data.  Must be < 2^24, as the

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;
 }
 

wsutil/filesystem.c

@@ -2265,7 +2265,7 @@ gboolean
 copy_file_binary_mode(const char *from_filename, const char *to_filename)
 {
     int           from_fd, to_fd, err;
-    ssize_t       nread, nwritten;
+    int           nread, nwritten;
     guint8        *pd = NULL;
 
     /* Copy the raw bytes of the file. */