Add a Windows-specific fallback to getenv("HOME");

This fixes msysGit issue 482 properly.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

compat/mingw.c

@@ -1969,6 +1969,23 @@ pid_t waitpid(pid_t pid, int *status, int options)
 	return -1;
 }
 
+const char *get_windows_home_directory(void)
+{
+	static const char *home_directory = NULL;
+	struct strbuf buf = STRBUF_INIT;
+
+	if (home_directory)
+		return home_directory;
+
+	home_directory = getenv("HOME");
+	if (home_directory && *home_directory)
+		return home_directory;
+
+	strbuf_addf(&buf, "%s/%s", getenv("HOMEDRIVE"), getenv("HOMEPATH"));
+	home_directory = strbuf_detach(&buf, NULL);
+
+	return home_directory;
+}
 int xutftowcsn(wchar_t *wcs, const char *utfs, size_t wcslen, int utflen)
 {
 	int upos = 0, wpos = 0;
@@ -2158,3 +2175,27 @@ void mingw_startup()
 	/* initialize Unicode console */
 	winansi_init();
 }
+
+int mingw_offset_1st_component(const char *path)
+{
+	int offset = 0;
+	if (has_dos_drive_prefix(path))
+		offset = 2;
+
+	/* unc paths */
+	else if (is_dir_sep(path[0]) && is_dir_sep(path[1])) {
+
+		/* skip server name */
+		char *pos = strpbrk(path + 2, "\\/");
+		if (!pos)
+			return 0; /* Error: malformed unc path */
+
+		do {
+			pos++;
+		} while (*pos && !is_dir_sep(*pos));
+
+		offset = pos - path;
+	}
+
+	return offset + is_dir_sep(path[offset]);
+}

compat/mingw.h

@@ -487,3 +487,6 @@ static int mingw_main(c,v)
  * Used by Pthread API implementation for Windows
  */
 extern int err_win_to_posix(DWORD winerr);
+
+extern const char *get_windows_home_directory();
+#define get_home_directory() get_windows_home_directory()

git-compat-util.h

@@ -727,4 +727,8 @@ struct tm *git_gmtime_r(const time_t *, struct tm *);
 #define mark_as_git_dir(x) /* noop */
 #endif
 
+#ifndef get_home_directory
+#define get_home_directory() getenv("HOME")
+#endif
+
 #endif

path.c

@@ -133,7 +133,7 @@ char *git_path(const char *fmt, ...)
 void home_config_paths(char **global, char **xdg, char *file)
 {
 	char *xdg_home = getenv("XDG_CONFIG_HOME");
-	char *home = getenv("HOME");
+	const char *home = get_home_directory();
 	char *to_free = NULL;
 
 	if (!home) {
@@ -274,7 +274,7 @@ char *expand_user_path(const char *path)
 		const char *username = path + 1;
 		size_t username_len = first_slash - username;
 		if (username_len == 0) {
-			const char *home = getenv("HOME");
+			const char *home = get_home_directory();
 			if (!home)
 				goto return_null;
 			strbuf_add(&user_path, home, strlen(home));

shell.c

@@ -55,7 +55,7 @@ static char *make_cmd(const char *prog)
 
 static void cd_to_homedir(void)
 {
-	const char *home = getenv("HOME");
+	const char *home = get_home_directory();
 	if (!home)
 		die("could not determine user's home directory; HOME is unset");
 	if (chdir(home) == -1)