From 9d595fd00d6c6e213f274046b7f61cb1f9b9837f Mon Sep 17 00:00:00 2001
From: skarg <skarg@1e814d3a-8a88-4260-be86-c0dc25669c1e>
Date: Mon, 27 Jul 2015 18:56:06 +0000
Subject: [PATCH] Fixed Wireshark extcap command line parameter interface to
 mstpcap utility on Windows (Thank you Roland!). Tested with Wireshark 1.99.7
 on Windows. To use extcap, run Wireshark and go to the About-dialog.  Find a
 tab located there named "Folders". Locate the extcap search path. Copy the
 mstpcap.exe to that folder, which may not exist. Restart Wireshark, and look
 for "BACnet MS/TP on COMx" interfaces. Configure the interface to change baud
 rate. Start or stop the capture directly from the interface.

---
 bacnet-stack/demo/mstpcap/main.c | 72 +++++++++++++-------------------
 1 file changed, 29 insertions(+), 43 deletions(-)

diff --git a/bacnet-stack/demo/mstpcap/main.c b/bacnet-stack/demo/mstpcap/main.c
index 9842dd69..37aad352 100644
--- a/bacnet-stack/demo/mstpcap/main.c
+++ b/bacnet-stack/demo/mstpcap/main.c
@@ -433,47 +433,35 @@ uint16_t MSTP_Get_Reply(
 static char Capture_Filename[32] = "mstp_20090123091200.cap";
 static FILE *pFile = NULL;      /* stream pointer */
 #if defined(_WIN32)
-static HANDLE hPipe = NULL;     /* pipe handle */
-static PSECURITY_DESCRIPTOR pPipeSD = NULL;
+static HANDLE hPipe = INVALID_HANDLE_VALUE;     /* pipe handle */
 static void named_pipe_create(
-    char *name)
+    char *pipe_name)
 {
-    SECURITY_ATTRIBUTES sa;
-
-    pPipeSD = (PSECURITY_DESCRIPTOR)(malloc(SECURITY_DESCRIPTOR_MIN_LENGTH));
-    if (!pPipeSD) {
-        Exit_Requested = true;
-        return;
-    }
-    if (!InitializeSecurityDescriptor(pPipeSD, SECURITY_DESCRIPTOR_REVISION)) {
-        free(pPipeSD);
-        pPipeSD = NULL;
-        Exit_Requested = true;
-        return;
-    }
-    /* When an object has no DACL (when the pDacl parameter is NULL),
-       no protection is assigned to the object, and all access requests
-       are granted. To help maintain security, restrict access by using
-       a DACL. */
-    if (!SetSecurityDescriptorDacl(pPipeSD, TRUE, (PACL)NULL, FALSE)) {
-        free(pPipeSD);
-        pPipeSD = NULL;
-        Exit_Requested = true;
-        return;
-    }
-    // now set up the security attributes
-    sa.nLength = sizeof(SECURITY_ATTRIBUTES);
-    sa.lpSecurityDescriptor = pPipeSD;
-    sa.bInheritHandle = TRUE;
-    fprintf(stdout, "mstpcap: Creating Named Pipe \"%s\"\n", name);
-    hPipe =
-        CreateNamedPipe(name, PIPE_ACCESS_OUTBOUND,
-        PIPE_TYPE_MESSAGE | PIPE_WAIT,
-        PIPE_UNLIMITED_INSTANCES, 65536, 65536, 0L, &sa);
-    if (hPipe == INVALID_HANDLE_VALUE) {
-        RS485_Print_Error();
-        Exit_Requested = true;
-        return;
+    fprintf(stdout, "mstpcap: Creating Named Pipe \"%s\"\n", pipe_name);
+    /* create the pipe */
+    while (hPipe == INVALID_HANDLE_VALUE)
+    {
+        /* use CreateFile rather than CreateNamedPipe */
+        hPipe = CreateFile(
+            pipe_name,
+            GENERIC_READ |
+            GENERIC_WRITE,
+            0,
+            NULL,
+            OPEN_EXISTING,
+            0,
+            NULL);
+        if (hPipe != INVALID_HANDLE_VALUE) {
+            break;
+        }
+        /* if an error occured at handle creation */
+        if (!WaitNamedPipe(pipe_name, 20000)) {
+            printf("Could not open pipe: waited for 20sec!\n"
+                "If this message was issued before the 20sec finished,\n"
+                "then the pipe doesn't exist!\n");
+            Exit_Requested = true;
+            return;
+        }
     }
     ConnectNamedPipe(hPipe, NULL);
 }
@@ -864,13 +852,11 @@ static BOOL WINAPI CtrlCHandler(
 {
     dwCtrlType = dwCtrlType;
 
-    if (hPipe) {
+    if (hPipe != INVALID_HANDLE_VALUE) {
         FlushFileBuffers(hPipe);
         DisconnectNamedPipe(hPipe);
         CloseHandle(hPipe);
-    }
-    if (pPipeSD) {
-        free(pPipeSD);
+        hPipe = INVALID_HANDLE_VALUE;
     }
     /* signal to main loop to exit */
     Exit_Requested = true;