Document the "copy-some-dirlinks" trick in the man page.

[rsync/rsync.git] / syscall.c

diff --git a/syscall.c b/syscall.c
index 2d704a8..aba0009 100644 (file)
--- a/syscall.c
+++ b/syscall.c
@@ -31,6 +31,7 @@
 
 extern int dry_run;
 extern int am_root;
+extern int am_sender;
 extern int read_only;
 extern int list_only;
 extern int preserve_perms;
@@ -58,8 +59,48 @@ int do_symlink(const char *lnk, const char *fname)
 {
        if (dry_run) return 0;
        RETURN_ERROR_IF_RO_OR_LO;
+
+#ifdef NO_SYMLINK_XATTRS
+       /* For --fake-super, we create a normal file with mode 0600
+        * and write the lnk into it. */
+       if (am_root < 0) {
+               int ok, len = strlen(lnk);
+               int fd = open(fname, O_WRONLY|O_CREAT|O_TRUNC, S_IWUSR|S_IRUSR);
+               if (fd < 0)
+                       return -1;
+               ok = write(fd, lnk, len) == len;
+               if (close(fd) < 0)
+                       ok = 0;
+               return ok ? 0 : -1;
+       }
+#endif
+
        return symlink(lnk, fname);
 }
+
+#ifdef NO_SYMLINK_XATTRS
+ssize_t do_readlink(const char *path, char *buf, size_t bufsiz)
+{
+       /* For --fake-super, we read the link from the file. */
+       if (am_root < 0) {
+               int fd = open(path, O_RDONLY|O_NOFOLLOW);
+               if (fd >= 0) {
+                       int len = read(fd, buf, bufsiz);
+                       close(fd);
+                       return len;
+               }
+               if (errno != ELOOP)
+                       return -1;
+               /* A real symlink needs to be turned into a fake one on the receiving
+                * side, so tell the generator that the link has no length. */
+               if (!am_sender)
+                       return 0;
+               /* Otherwise fall through and let the sender report the real length. */
+       }
+
+       return readlink(path, buf, bufsiz);
+}
+#endif
 #endif
 
 #ifdef HAVE_LINK
@@ -154,10 +195,11 @@ int do_chmod(const char *path, mode_t mode)
        int code;
        if (dry_run) return 0;
        RETURN_ERROR_IF_RO_OR_LO;
-       if (S_ISLNK(mode)) {
 #ifdef HAVE_LCHMOD
-               code = lchmod(path, mode & CHMOD_BITS);
-#elif defined HAVE_SETATTRLIST
+       code = lchmod(path, mode & CHMOD_BITS);
+#else
+       if (S_ISLNK(mode)) {
+# if defined HAVE_SETATTRLIST
                struct attrlist attrList;
                uint32_t m = mode & CHMOD_BITS; /* manpage is wrong: not mode_t! */
 
@@ -165,11 +207,12 @@ int do_chmod(const char *path, mode_t mode)
                attrList.bitmapcount = ATTR_BIT_MAP_COUNT;
                attrList.commonattr = ATTR_CMN_ACCESSMASK;
                code = setattrlist(path, &attrList, &m, sizeof m, FSOPT_NOFOLLOW);
-#else
+# else
                code = 1;
-#endif
+# endif
        } else
                code = chmod(path, mode & CHMOD_BITS); /* DISCOURAGED FUNCTION */
+#endif /* !HAVE_LCHMOD */
        if (code != 0 && (preserve_perms || preserve_executability))
                return code;
        return 0;