From eb071de23087ea19bfeb203c34479ea9f04e49fd Mon Sep 17 00:00:00 2001
From: XANTRONIX Development <dev@xantronix.com>
Date: Wed, 5 Aug 2020 22:38:49 -0400
Subject: [PATCH] Add SOCK_PARAMS to patty_client_setsockopt()

Add SOCK_PARAMS to patty_client_setsockopt() to allow for setting
(presently) the MTU and TX window of a given socket to accommodate the
needs of specific remote stations
---
 include/patty/ax25/sock.h |  5 +++++
 include/patty/client.h    |  5 +++++
 src/server.c              | 18 ++++++++++++++++++
 src/sock.c                |  8 ++++++++
 4 files changed, 36 insertions(+)

diff --git a/include/patty/ax25/sock.h b/include/patty/ax25/sock.h
index 08407cd..68bf94f 100644
--- a/include/patty/ax25/sock.h
+++ b/include/patty/ax25/sock.h
@@ -64,6 +64,7 @@ enum patty_ax25_sock_flow {
 };
 
 enum patty_ax25_sock_opt {
+    PATTY_AX25_SOCK_PARAMS,
     PATTY_AX25_SOCK_IF
 };
 
@@ -127,6 +128,10 @@ void patty_ax25_sock_init(patty_ax25_sock *sock);
 
 void patty_ax25_sock_reset(patty_ax25_sock *sock);
 
+void patty_ax25_sock_mtu_set(patty_ax25_sock *sock, size_t mtu);
+
+void patty_ax25_sock_window_set(patty_ax25_sock *sock, size_t window);
+
 void patty_ax25_sock_params_upgrade(patty_ax25_sock *sock);
 
 void patty_ax25_sock_params_max(patty_ax25_sock *sock);
diff --git a/include/patty/client.h b/include/patty/client.h
index d5c34af..8a3d948 100644
--- a/include/patty/client.h
+++ b/include/patty/client.h
@@ -56,6 +56,11 @@ typedef struct _patty_client_setsockopt_request {
     size_t len;
 } patty_client_setsockopt_request;
 
+typedef struct _patty_client_setsockopt_params {
+    size_t mtu,
+           window;
+} patty_client_setsockopt_params;
+
 typedef struct _patty_client_setsockopt_if {
     char name[8];
     int status;
diff --git a/src/server.c b/src/server.c
index d2793ca..19ee9ac 100644
--- a/src/server.c
+++ b/src/server.c
@@ -590,6 +590,23 @@ static int server_setsockopt(patty_ax25_server *server,
     }
 
     switch (request.opt) {
+        case PATTY_AX25_SOCK_PARAMS: {
+            patty_client_setsockopt_params data;
+
+            if (read(client, &data, request.len) < 0) {
+                goto error_read;
+            }
+
+            if (data.mtu)    patty_ax25_sock_mtu_set(sock,    data.mtu);
+            if (data.window) patty_ax25_sock_window_set(sock, data.window);
+
+            if (patty_ax25_sock_realloc_bufs(sock) < 0) {
+                goto error_realloc_bufs;
+            }
+
+            break;
+        }
+
         case PATTY_AX25_SOCK_IF: {
             patty_client_setsockopt_if data;
             patty_ax25_if *iface;
@@ -639,6 +656,7 @@ error_invalid_type:
 error_invalid_opt:
     return write(client, &response, sizeof(response));
 
+error_realloc_bufs:
 error_read:
     return -1;
 }
diff --git a/src/sock.c b/src/sock.c
index 6c50e7d..0bf35c5 100644
--- a/src/sock.c
+++ b/src/sock.c
@@ -227,6 +227,14 @@ void patty_ax25_sock_reset(patty_ax25_sock *sock) {
     patty_timer_clear(&sock->timer_t3);
 }
 
+void patty_ax25_sock_mtu_set(patty_ax25_sock *sock, size_t mtu) {
+    sock->n_maxlen_tx = mtu;
+}
+
+void patty_ax25_sock_window_set(patty_ax25_sock *sock, size_t window) {
+    sock->n_window_tx = window;
+}
+
 void patty_ax25_sock_params_upgrade(patty_ax25_sock *sock) {
     if (sock->version >= PATTY_AX25_2_2) {
         return;