Introduce has_dos_drive_prefix() and use it.

This function tests whether there is a C: style prefix in the argument.
It returns always 0 on Unix.

With this functions a number of conditionals #ifdef __MINGW32__/#endif
can be removed.

The getcwd() replacement was simplified: It tried to elide the translation
of backslashes to slashes if there was no drive prfix, but this
optimization is wrong: We could be looking at an UNC path, which we also
want to translate.

Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>

cache.h

@@ -484,11 +484,7 @@ int safe_create_leading_directories(char *path);
 char *enter_repo(char *path, int strict);
 static inline int is_absolute_path(const char *path)
 {
-#ifndef __MINGW32__
-	return path[0] == '/';
-#else
-	return path[0] == '/' || (path[0] && path[1] == ':');
-#endif
+	return path[0] == '/' || has_dos_drive_prefix(path);
 }
 const char *make_absolute_path(const char *path);
 

compat/mingw.c

@@ -330,16 +330,13 @@ struct tm *localtime_r(const time_t *timep, struct tm *result)
 #undef getcwd
 char *mingw_getcwd(char *pointer, int len)
 {
+	int i;
 	char *ret = getcwd(pointer, len);
 	if (!ret)
 		return ret;
-	if (pointer[0] != 0 && pointer[1] == ':') {
-		int i;
-		for (i = 2; pointer[i]; i++)
-			/* Thanks, Bill. You'll burn in hell for that. */
-			if (pointer[i] == '\\')
-				pointer[i] = '/';
-	}
+	for (i = 0; pointer[i]; i++)
+		if (pointer[i] == '\\')
+			pointer[i] = '/';
 	return ret;
 }
 

connect.c

@@ -528,13 +528,7 @@ struct child_process *git_connect(int fd[2], const char *url_orig,
 		end = host;
 
 	path = strchr(end, c);
-#ifdef __MINGW32__
-	/* host must have at least 2 chars to catch DOS C:/path */
-	if (path && path - end > 1)
-#else
-	if (path)
-#endif
-	{
+	if (path && !has_dos_drive_prefix(end)) {
 		if (c == ':') {
 			protocol = PROTO_SSH;
 			*path++ = '\0';

git-compat-util.h

@@ -650,6 +650,18 @@ char **copy_environ(void);
 void free_environ(char **env);
 char **env_setenv(char **env, const char *name);
 
+static inline int has_dos_drive_prefix(const char *path)
+{
+	return isalpha(*path) && path[1] == ':';
+}
+
+#else /* __MINGW32__ */
+
+static inline int has_dos_drive_prefix(const char *path)
+{
+	return 0;
+}
+
 #endif /* __MINGW32__ */
 
 #endif

setup.c

@@ -397,10 +397,8 @@ const char *setup_git_directory_gently(int *nongit_ok)
 
 	if (!getcwd(cwd, sizeof(cwd)-1))
 		die("Unable to read current working directory");
-#ifdef __MINGW32__
-	if (cwd[1] == ':')
+	if (has_dos_drive_prefix(cwd))
 		minoffset = 2;
-#endif
 
 	/*
 	 * Test in the following order (relative to the cwd):

sha1_file.c

@@ -85,10 +85,8 @@ int get_sha1_hex(const char *hex, unsigned char *sha1)
 
 static inline int offset_1st_component(const char *path)
 {
-#ifdef __MINGW32__
-	if (isalpha(path[0]) && path[1] == ':')
+	if (has_dos_drive_prefix(path))
 		return 2 + (path[2] == '/');
-#endif
 	return *path == '/';
 }