Test for WIN32 instead of __MINGW32_

The code which is conditional on MinGW32 is actually conditional on Windows.
Use the WIN32 symbol, which is defined by the MINGW32 and MSVC environments,
but not by Cygwin.

Define SNPRINTF_SIZE_CORR=1 for MSVC too, as its vsnprintf function does
not add NUL at the end of the buffer if the result fits the buffer size
exactly.

Signed-off-by: Frank Li <lznuaa@gmail.com>
Signed-off-by: Marius Storm-Olsen <mstormo@gmail.com>
Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

compat/snprintf.c

@@ -2,12 +2,14 @@
 
 /*
  * The size parameter specifies the available space, i.e. includes
- * the trailing NUL byte; but Windows's vsnprintf expects the
+ * the trailing NUL byte; but Windows's vsnprintf uses the entire
- * number of characters to write, and does not necessarily write the
+ * buffer and avoids the trailing NUL, should the buffer be exactly
- * trailing NUL.
+ * big enough for the result. Defining SNPRINTF_SIZE_CORR to 1 will
+ * therefore remove 1 byte from the reported buffer size, so we
+ * always have room for a trailing NUL byte.
  */
 #ifndef SNPRINTF_SIZE_CORR
-#if defined(__MINGW32__) && defined(__GNUC__) && __GNUC__ < 4
+#if defined(WIN32) && (!defined(__GNUC__) || __GNUC__ < 4)
 #define SNPRINTF_SIZE_CORR 1
 #else
 #define SNPRINTF_SIZE_CORR 0

help.c

@@ -126,7 +126,7 @@ static int is_executable(const char *name)
 	    !S_ISREG(st.st_mode))
 		return 0;
 
-#ifdef __MINGW32__
+#ifdef WIN32
 {	/* cannot trust the executable bit, peek into the file instead */
 	char buf[3] = { 0 };
 	int n;

pager.c

@@ -9,7 +9,7 @@
 
 static int spawned_pager;
 
-#ifndef __MINGW32__
+#ifndef WIN32
 static void pager_preexec(void)
 {
 	/*
@@ -72,7 +72,7 @@ void setup_pager(void)
 		static const char *env[] = { "LESS=FRSX", NULL };
 		pager_process.env = env;
 	}
-#ifndef __MINGW32__
+#ifndef WIN32
 	pager_process.preexec_cb = pager_preexec;
 #endif
 	if (start_command(&pager_process))

run-command.c

@@ -75,7 +75,7 @@ fail_pipe:
 
 	trace_argv_printf(cmd->argv, "trace: run_command:");
 
-#ifndef __MINGW32__
+#ifndef WIN32
 	fflush(NULL);
 	cmd->pid = fork();
 	if (!cmd->pid) {
@@ -315,7 +315,7 @@ int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const
 	return run_command(&cmd);
 }
 
-#ifdef __MINGW32__
+#ifdef WIN32
 static unsigned __stdcall run_thread(void *data)
 {
 	struct async *async = data;
@@ -331,7 +331,7 @@ int start_async(struct async *async)
 		return error("cannot create pipe: %s", strerror(errno));
 	async->out = pipe_out[0];
 
-#ifndef __MINGW32__
+#ifndef WIN32
 	/* Flush stdio before fork() to avoid cloning buffers */
 	fflush(NULL);
 
@@ -360,7 +360,7 @@ int start_async(struct async *async)
 
 int finish_async(struct async *async)
 {
-#ifndef __MINGW32__
+#ifndef WIN32
 	int ret = wait_or_whine(async->pid, "child process", 0);
 #else
 	DWORD ret = 0;

run-command.h

@@ -70,7 +70,7 @@ struct async {
 	int (*proc)(int fd, void *data);
 	void *data;
 	int out;	/* caller reads from here and closes it */
-#ifndef __MINGW32__
+#ifndef WIN32
 	pid_t pid;
 #else
 	HANDLE tid;

setup.c

@@ -41,7 +41,7 @@ const char *prefix_path(const char *prefix, int len, const char *path)
 const char *prefix_filename(const char *pfx, int pfx_len, const char *arg)
 {
 	static char path[PATH_MAX];
-#ifndef __MINGW32__
+#ifndef WIN32
 	if (!pfx || !*pfx || is_absolute_path(arg))
 		return arg;
 	memcpy(path, pfx, pfx_len);