mingw: implement basic `symlink()` functionality (file symlinks only)

Implement `symlink()`. This implementation always creates _file_
symlinks (remember: Windows discerns between symlinks pointing to
directories and those pointing to files). Support for directory symlinks
will be added in a subseqeuent commit.

This implementation fails with `ENOSYS` if symlinks are disabled or
unsupported.

Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/compat/mingw-posix.h b/compat/mingw-posix.h
index 896aa976b1949b854837651f6c762eab5083e807..2d989fd762474ec8d1051cf7e858a2d547d2074a 100644 (file)
--- a/compat/mingw-posix.h
+++ b/compat/mingw-posix.h
@@ -121,8 +121,6 @@ struct utsname {
  * trivial stubs
  */
 
-static inline int symlink(const char *oldpath UNUSED, const char *newpath UNUSED)
-{ errno = ENOSYS; return -1; }
 static inline int fchmod(int fildes UNUSED, mode_t mode UNUSED)
 { errno = ENOSYS; return -1; }
 #ifndef __MINGW64_VERSION_MAJOR
@@ -195,6 +193,7 @@ int setitimer(int type, struct itimerval *in, struct itimerval *out);
 int sigaction(int sig, struct sigaction *in, struct sigaction *out);
 int link(const char *oldpath, const char *newpath);
 int uname(struct utsname *buf);
+int symlink(const char *target, const char *link);
 int readlink(const char *path, char *buf, size_t bufsiz);
 
 /*

diff --git a/compat/mingw.c b/compat/mingw.c
index b407a2ac07f9d48e20a30a6b8b01cdd8956f332d..8d366794c44e5501c2bea6ee44cb5166bf9689f7 100644 (file)
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -2698,6 +2698,34 @@ int link(const char *oldpath, const char *newpath)
        return 0;
 }
 
+int symlink(const char *target, const char *link)
+{
+       wchar_t wtarget[MAX_PATH], wlink[MAX_PATH];
+       int len;
+
+       /* fail if symlinks are disabled or API is not supported (WinXP) */
+       if (!has_symlinks) {
+               errno = ENOSYS;
+               return -1;
+       }
+
+       if ((len = xutftowcs_path(wtarget, target)) < 0
+                       || xutftowcs_path(wlink, link) < 0)
+               return -1;
+
+       /* convert target dir separators to backslashes */
+       while (len--)
+               if (wtarget[len] == '/')
+                       wtarget[len] = '\\';
+
+       /* create file symlink */
+       if (!CreateSymbolicLinkW(wlink, wtarget, 0)) {
+               errno = err_win_to_posix(GetLastError());
+               return -1;
+       }
+       return 0;
+}
+
 int readlink(const char *path, char *buf, size_t bufsiz)
 {
        WCHAR wpath[MAX_PATH];