From 6a0437d30c9408415e92e4aada17711ebbdef537 Mon Sep 17 00:00:00 2001
From: Sapan Bhatia <sapanb@cs.princeton.edu>
Date: Thu, 2 Apr 2009 19:47:19 +0000
Subject: [PATCH] Checking in KyoungSoo's changes for dynamically setting
 buffer sizes

---
 fd_bmsocket.c | 55 +++++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 49 insertions(+), 6 deletions(-)

diff --git a/fd_bmsocket.c b/fd_bmsocket.c
index 334b51e..6a830ed 100644
--- a/fd_bmsocket.c
+++ b/fd_bmsocket.c
@@ -5,10 +5,28 @@
 #include <errno.h>
 #include "fdpass.h"
 
-unsigned int rcvbuf = 16*1024*1024;
+#define MAX_BUFSIZE (32*1024*1024)
 
-int main(int argc, char *argv[]) {
+/*------------------------------------------------------------------*/
+void
+receive_argument(int control_fd, int *rcvbuf, int *sndbuf)
+{
+  if (recv(control_fd, rcvbuf, sizeof(int), 0) != sizeof(int)) {
+    fprintf(stderr, "receiving the first argument failed\n");
+    exit(-1);
+  }
+  if (recv(control_fd, sndbuf, sizeof(int), 0) != sizeof(int)) {
+    fprintf(stderr, "receiving the first argument failed\n");
+    exit(-1);
+  }
+}
+/*------------------------------------------------------------------*/
+int 
+main(int argc, char *argv[]) 
+{
     int control_channel_fd, magic_socket;
+    int rcvbufsize = 0, sndbufsize = 0;
+    
     if (argc < 3) {
         printf("This script is called by vsys.\n");
         exit(1);
@@ -16,15 +34,40 @@ int main(int argc, char *argv[]) {
 
     sscanf(argv[2],"%d", &control_channel_fd);
 
-    magic_socket = socket(AF_INET, SOCK_STREAM, 0);
+    /* receive paramaters: rcvbufsize and sndbufsize */
+    receive_argument(control_channel_fd, &rcvbufsize, &sndbufsize);
+    if (rcvbufsize > MAX_BUFSIZE)
+      rcvbufsize = MAX_BUFSIZE;
+    if (sndbufsize > MAX_BUFSIZE)
+      sndbufsize = MAX_BUFSIZE;
 
+    magic_socket = socket(AF_INET, SOCK_STREAM, 0);
     if (magic_socket == -1) {
-        printf("Error creating socket: %d\n", errno);
+      fprintf(stderr, "Error creating socket: %d\n", errno);
+      exit(1);
+    }
+
+    /* buffer size <= 0 means we should ignore the parameter */
+    if (rcvbufsize > 0) {
+      if (setsockopt(magic_socket, 
+		     SOL_SOCKET, 
+		     SO_RCVBUFFORCE, 
+		     &rcvbufsize, sizeof(unsigned int))) {
+        fprintf(stderr, "Error calling setsockopt for RCVBUFFORCE: %d\n", 
+		errno);
         exit(1);
+      }
     }
-    if (setsockopt(magic_socket, SOL_SOCKET, SO_RCVBUFFORCE, &rcvbuf, sizeof(unsigned int))) {
-        printf("Error calling setsockopt: %d\n", errno);
+    if (sndbufsize > 0) {
+      if (setsockopt(magic_socket, 
+		     SOL_SOCKET, 
+		     SO_SNDBUFFORCE, 
+		     &sndbufsize, sizeof(unsigned int))) {
+        fprintf(stderr, "Error calling setsockopt for SNDBUFFORCE: %d\n", 
+		errno);
         exit(1);
+      }
     }
+
     send_fd(control_channel_fd, magic_socket);
 }
-- 
2.43.0