Add mtu option

This reverts commit 03cd87df1c.

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "mud"]
+	path = mud
+	url = https://github.com/angt/mud.git

Makefile.am

@@ -20,6 +20,11 @@ glorytun_SOURCES = \
     src/state.c \
     src/state.h
 
+glorytun_CFLAGS  += -I$(srcdir)/mud
+glorytun_SOURCES += \
+    mud/mud.h \
+    mud/mud.c
+
 EXTRA_DIST = \
     LICENSE \
     README.md \

README.md

@@ -1,6 +1,6 @@
-# Glorytun
+# π₁(Glorytun)=ℤ²
 
-Small, Simple and Stupid TCP VPN.
+Small, Simple and Stupid VPN over [mud](https://github.com/angt/mud).
 
 #### Work In Progress
 
@@ -13,7 +13,7 @@ and needs an AES-NI capable CPU.
 
 To build and install the latest version:
 
-    $ git clone https://github.com/angt/glorytun
+    $ git clone https://github.com/angt/glorytun --recursive --branch mud
     $ cd glorytun
     $ ./autogen.sh
     $ ./configure

src/state.c

@@ -7,16 +7,14 @@
 #include <fcntl.h>
 #include <sys/stat.h>
 
-static int state_fd = -1;
-
-int state_init (const char *filename)
+int state_create (const char *filename)
 {
     if (str_empty(filename))
-        return 0;
+        return -1;
 
-    state_fd = open(filename, O_WRONLY);
+    int fd = open(filename, O_WRONLY);
 
-    if (state_fd==-1) {
+    if (fd==-1) {
         if (errno!=EINTR)
             perror("open");
         return -1;
@@ -24,38 +22,41 @@ int state_init (const char *filename)
 
     struct stat st = {0};
 
-    if (fstat(state_fd, &st)==-1) {
+    if (fstat(fd, &st)==-1) {
         perror("fstat");
-        close(state_fd);
-        state_fd = -1;
+        close(fd);
         return -1;
     }
 
     if (!S_ISFIFO(st.st_mode)) {
         gt_log("`%s' is not a fifo\n", filename);
-        close(state_fd);
-        state_fd = -1;
+        close(fd);
         return -1;
     }
 
-    return 0;
+    return fd;
 }
 
-void state (const char *state, const char *info)
+void state_send (int fd, const char *state, const char *info)
 {
     if (str_empty(state))
         return;
 
+    if (fd==-1) {
+        gt_print("%s %s\n", state, info);
+        return;
+    }
+
     const char *strs[] = { state, " ", info, "\n" };
     char *str = str_cat(strs, COUNT(strs));
 
-    if (!str)
+    if (!str) {
+        perror("str_cat");
         return;
-
-    if (state_fd==-1) {
-        gt_print("%s", str);
-    } else {
-        if (write(state_fd, str, str_len(str))==-1 && errno!=EINTR)
-            perror("write");
     }
+
+    if (write(fd, str, str_len(str))==-1 && errno!=EINTR)
+        perror("write");
+
+    free(str);
 }

src/state.h

@@ -1,4 +1,4 @@
 #pragma once
 
-int  state_init (const char *);
-void state      (const char *, const char *);
+int  state_create (const char *);
+void state_send   (int, const char *, const char *);