I found some sample code for device manager information, I try to write on txt file but there will stop working.
I don't know what is the root cause for this problem.
below link is the original sample code.
http://white5168.blogspot.com/2013/05/drivercmgetdevnodestatus.html#.W1FLpdIzaM9
below code is where I added.
Please help to check.
while (!SetupDiGetDeviceRegistryProperty(hDevInfo,
&DeviceInfoData,
ucSPDRP[j],
&DataType,
(PBYTE)Buffer,
BufferSize,
&BufferSize)) {
if (GetLastError() == ERROR_INSUFFICIENT_BUFFER)
{
// Change the buffer size.
if (Buffer) LocalFree(Buffer);
Buffer = (LPSTR)LocalAlloc(LPTR, BufferSize * 2);
}
else
break;// Insert error handling here.
}
file << cStatus[j];
file << (const char *)Buffer << "\n";
file.flush();
}
printf("%s : %s\n", cStatus[j], (const char *)Buffer);
if (Buffer) LocalFree(Buffer);
Related
I am using CreateNamedPipe. It returns 0XFFFFFFFF but when I call GetLastError and perror I get "NO ERROR".
I have checked https://learn.microsoft.com/en-us/windows/win32/ipc/multithreaded-pipe-server and I heve coded very similar.
I coded this using an example provided here: https://stackoverflow.com/questions/47731784/c-createnamedpipe-error-path-not-found-3#= and he says it means ERROR_PATH_NOT_FOUND (3). But my address is "\\.\pipe\pipe_com1. Note that StackOverflow seems to remove the extra slashes but you will see them in the paste of my code.
I followed the example here: Create Named Pipe C++ Windows but I still get the error. Here is my code:
// Create a named pipe
// It is used to test TcpToNamedPipe to be sore it it is addressing the named pipe
#include <windows.h>
#include <stdio.h>
#include <process.h>
char ch;
int main(int nargs, char** argv)
{
if (nargs != 2)
{
printf("Usage pipe name is first arg\n");
printf("press any key to exit ");
scanf("%c", &ch);
return -1;
}
char buffer[1024];
HANDLE hPipe;
DWORD dwRead;
sprintf(buffer, "\\\\.\\pipe\\%s", argv[1]);
hPipe = CreateNamedPipe((LPCWSTR)buffer,
PIPE_ACCESS_DUPLEX,
PIPE_TYPE_BYTE | PIPE_READMODE_BYTE | PIPE_WAIT, // FILE_FLAG_FIRST_PIPE_INSTANCE is not needed but forces CreateNamedPipe(..) to fail if the pipe already exists...
1,
1024*16,
1024*16,
NMPWAIT_USE_DEFAULT_WAIT,
NULL);
if (hPipe == INVALID_HANDLE_VALUE)
{
//int errorno = GetLastError();
//printf("error creating pipe %d\n", errorno);
perror("");
printf("press any key to exit ");
scanf("%c", &ch);
return -1;
}
while (hPipe != INVALID_HANDLE_VALUE)
{
if (ConnectNamedPipe(hPipe, NULL) != FALSE) // wait for someone to connect to the pipe
{
while (ReadFile(hPipe, buffer, sizeof(buffer) - 1, &dwRead, NULL) != FALSE)
{
/* add terminating zero */
buffer[dwRead] = '\0';
/* do something with data in buffer */
printf("%s", buffer);
}
}
DisconnectNamedPipe(hPipe);
}
return 0;
}
I'm guessing that the pointer to the address may be wrong and CreateNamedPipe is not seeing the name of the pipe properly. So I used disassembly and notice that the address is in fact a far pointer. Here is that disassembly:
00CA1A45 mov esi,esp
00CA1A47 push 0
00CA1A49 push 0
00CA1A4B push 4000h
00CA1A50 push 4000h
00CA1A55 push 1
00CA1A57 push 0
00CA1A59 push 3
00CA1A5B lea eax,[buffer]
00CA1A61 push eax
00CA1A62 call dword ptr [__imp__CreateNamedPipeW#32 (0CAB00Ch)]
Can someone spot my problem?
I'm doing a script using CAPL and am stuck for a solution to grep the login ID from Windows. Could some please help show how to get Windows user login ID from within a CAPL program code, if this is possible?
For example, if the Windows user login ID is 'kp21ml' , I want to read this ID from a CAPL function, as shown below.
byte UserIdCheck()
{
char uid[10];
byte CanMessageTrasmission;
strncpy(uid, xxxx(), 6); // where xxxx() is the unknown OS or system function that could return the login ID ?
if (strncmp(uid, "kp21ml") != 0)
{
write("Access denied!"); // Message to CANoe's Write window
CanMessageTrasmission = 0;
}
else
{
// Access ok
CanMessageTrasmission = 1;
}
return CanMessageTrasmission;
}
I use this CAPL book as my reference guide, which is very good:
http://docplayer.net/15013371-Programming-with-capl.html
But I couldn't find anything to do with system access. I would appreciate your help.
Thanks
Juno
I'm afraid you won't be able to do that directly from a CAPL script.
I generally create a CAPL-DLL and include that in my CANoe project when I need to access some OS level functionality. Though I use it mostly for accessing an external device (e.g. USB) or to interact with another program using sockets over local host, the principle is the same.
You can find more information in CANoe's documentation with examples but the CAPL-DLL source code provided in CANoe samples is a little difficult to understand.
I've attempted to strip some of the "unnecessary" parts in the following code sample; this example will create a CAPL-DLL which "exposes" the multiplyBy10 function and basically allows you to call multiplyBy10 from you CAPL script):
#define USECDLL_FEATURE
#define _BUILDNODELAYERDLL
#pragma warning( disable : 4786 )
#include "cdll.h"
#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <map>
char moduleName[_MAX_FNAME];
HINSTANCE moduleHandle;
unsigned int
CAPLEXPORT far CAPLPASCAL multiplyBy10 (unsigned char value)
{
unsigned int result = value * 10;
freopen("CONOUT$", "w", stdout);
std::cout << "multiplyBy10() - value: " << int(value) << ", result: " << result << std::endl;
return (result);
}
CAPL_DLL_INFO4 table[] =
{
{CDLL_VERSION_NAME, (CAPL_FARCALL)CDLL_VERSION, "", "", CAPL_DLL_CDECL, 0xABD, CDLL_EXPORT},
{"multiplyBy10", (CAPL_FARCALL)multiplyBy10, "CAPL_DLL", "This is a demo function", 'L', 1, "D", "", { "value"}},
{0, 0}
};
CAPLEXPORT CAPL_DLL_INFO4 far * caplDllTable4 = table;
bool
WINAPI DllMain(HINSTANCE handle, DWORD reason, void*)
{
static FILE * stream;
switch (reason)
{
case DLL_PROCESS_ATTACH:
{
moduleHandle = handle;
char path_buffer[_MAX_PATH];
DWORD result = GetModuleFileName(moduleHandle, path_buffer, _MAX_PATH);
char drive[_MAX_DRIVE];
char dir[_MAX_DIR];
char fname[_MAX_FNAME];
char ext[_MAX_EXT];
_splitpath_s(path_buffer, drive, dir, fname, ext);
strcpy_s(moduleName, fname);
AllocConsole();
freopen_s(&stream, "conout$", "w", stdout);
std::cout << "DLL_PROCESS_ATTACH" << std::endl;
return 1;
}
case DLL_PROCESS_DETACH:
{
std::cout << "DLL_PROCESS_DETACH" << std::endl;
FreeConsole();
fclose(stream);
return 1;
}
}
return 1;
}
I am implementing a communication between 2 processes using a queue. The problem is that when I call the function mq_receive, I get this error: Message too long.
I have done the following:
struct mq_attr attr;
long size = attr.mq_msgsize;
.... // initializing the queue "/gateway"
int rc = mq_receive(gateway, buffer, size, &prio);
If I print the size value, I get size=1, while when I print the same size but from another program (got by the same mechanism), I get something not long integer ( -1217186280 )...
How can I solve this error?....so while size = 1, I believe it's right to say "message too long" but why is 1?
P.S. I have also tried to put :
int rc = mq_receive(gateway, buffer, sizeof(buffer), &prio);
but with no result.
It seems like you need to read the docs more carefully. When you call mq_receive you should pass size of the destination buffer. This size must be greater than the mq_msgsize attribute of the queue. In addition, it seems like you have an error in queue attributes initialisation that makes proper mq_receive call impossible. Here is standard message queue session:
Fill mq_attr struct (doc):
struct mq_attr attr;
attr.mq_flags = 0;
attr.mq_maxmsg = 10;
attr.mq_msgsize = 33;
attr.mq_curmsgs = 0;
Create queue with mq_open in master process (doc):
mqd_t queue = mq_open(qname, O_CREAT|O_RDWR, 0644, &attr);
In writer process open queue for writing:
mqd_t queue = mq_open(qname, O_WRONLY);
And send some text. Length of the text must be lesser than mq_msgsize attribute of the queue (doc):
mq_send(queue, "some message", strlen("some message")+1, 1);
In reader process open queue for reading:
mqd_t queue = mq_open(qname, O_RDONLY);
And then allocate buffer and receive message. Size of buffer *must be greater than the mq_msgsize attribute of the queue. Here we create 50-byte buffer while mq_msgsize == 33 (doc):
char rcvmsg[50];
int iret = mq_receive(queue, rcvmsg, 50, NULL);
Also remember that you should use %ld for print long instead of %d.
When debugging realtime POSIX queues, you should start with a sample program which works and go forward from there. Once you have the sample program running, it should be a simple matter of ensuring that your own code follows all the steps.
The following program has been tested successfully under Ubuntu 11.04:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <mqueue.h>
#define MQNAME "/pax"
#define MQMESG "Hello there!"
static mqd_t serverUp (void) {
int rc;
mqd_t svrHndl;
struct mq_attr mqAttr;
printf ("Bringing up server.\n");
rc = mq_unlink (MQNAME);
if (rc < 0) {
printf (" Warning %d (%s) on server mq_unlink.\n",
errno, strerror (errno));
}
mqAttr.mq_maxmsg = 10;
mqAttr.mq_msgsize = 1024;
svrHndl = mq_open (MQNAME, O_RDWR|O_CREAT, S_IWUSR|S_IRUSR, &mqAttr);
if (svrHndl < 0) {
printf (" Error %d (%s) on server mq_open.\n",
errno, strerror (errno));
exit (1);
}
printf (" Server opened mqd_t of %d.\n", svrHndl);
return svrHndl;
}
static void serverReceive (mqd_t svrHndl) {
int rc;
char buffer[2048];
printf ("Server receiving on mqd_t %d.\n", svrHndl);
rc = mq_receive (svrHndl, buffer, sizeof (buffer), NULL);
if (rc < 0) {
printf (" Error %d (%s) on server mq_receive.\n",
errno, strerror (errno));
exit (1);
}
printf (" Received [%s].\n", buffer);
}
static void serverDown (mqd_t svrHndl) {
printf ("Bringing down server with mqd_t %d.\n", svrHndl);
mq_close (svrHndl);
}
static void clientSend (void) {
mqd_t cliHndl;
int rc;
printf ("Client sending.\n");
cliHndl = mq_open (MQNAME, O_RDWR);
if (cliHndl < 0) {
printf (" Error %d (%s) on client mq_open.\n",
errno, strerror (errno));
exit (1);
}
printf (" Client opened mqd_t of %d.\n", cliHndl);
rc = mq_send (cliHndl, MQMESG, sizeof (MQMESG), 1);
if (rc < 0) {
printf (" Error %d (%s) on client mq_send.\n",
errno, strerror (errno));
exit (1);
}
mq_close (cliHndl);
}
int main (void) {
mqd_t svrHndl;
svrHndl = serverUp ();
clientSend ();
serverReceive (svrHndl);
serverDown (svrHndl);
return 0;
}
The output on my system is:
Bringing up server.
Server opened mqd_t of 3.
Client sending.
Client opened mqd_t of 4.
Server receiving on mqd_t 3.
Received [Hello there!].
Bringing down server with mqd_t 3.
Don't forget to unlink the message queue before running your program again. If you dont unlink it, it will still use the old message queue settings. This happens when you end your program with Ctrl+C. I think it is a good idea to put the following code at the beginning of the program:
if(mq_unlink(QUEUENAME) == 0)
fprintf(stdout, "Message queue %s removed from system.\n", QUEUENAME);
An alternative form (C++ style) that checks for real errors (like permissions) and ignores the cases where the queue already exists or not:
int rc = mq_unlink(name.c_str());
if (rc != 0 && errno != ENOENT)
THROW_ERRNO_EXCEPTION();
// ENOENT is the status code if the queue doesn't exist, which is not an error
// if you are immediately going to create it.
Just a correction above...
"This size must be equal or greater than the mq_msgsize attribute of the queue"
Equal size is probably required if you are passing a struct instead of a buffer:
see: send struct in mq_send
hi guys how can i collect the packet length for each packet in the pcap file? thanks a lot
I suggest a high-tech method, which very few people know: reading the documentation.
man pcap tells us there are actually two different lengths available:
caplen a bpf_u_int32 giving the number of bytes of the packet that are
available from the capture
len a bpf_u_int32 giving the length of the packet, in bytes (which
might be more than the number of bytes available from the cap-
ture, if the length of the packet is larger than the maximum num-
ber of bytes to capture)
An example in C:
/* Grab a packet */
packet = pcap_next(handle, &header);
if (packet == NULL) { /* End of file */
break;
}
printf ("Got a packet with length of [%d] \n",
header.len);
Another one in Python with the pcapy library:
import pcapy
reader = pcapy.open_offline("packets.pcap")
while True:
try:
(header, payload) = reader.next()
print "Got a packet of length %d" % header.getlen()
except pcapy.PcapError:
break
Those two examples below work fine:
using C, WinPcap
using python, SCAPY
(WinPcap)(Compiler CL , Microsoft VC)
I have wrote this function (in C) to get packet size and it works fine.
Don't forget to include pcap.h and set HAVE_REMOTE in compiler preprocessors
u_int getpkt_size(char * pcapfile){
pcap_t *indesc;
char errbuf[PCAP_ERRBUF_SIZE];
char source[PCAP_BUF_SIZE];
u_int res;
struct pcap_pkthdr *pktheader;
u_char *pktdata;
u_int pktsize=0;
/* Create the source string according to the new WinPcap syntax */
if ( pcap_createsrcstr( source, // variable that will keep the source string
PCAP_SRC_FILE, // we want to open a file
NULL, // remote host
NULL, // port on the remote host
pcapfile, // name of the file we want to open
errbuf // error buffer
) != 0)
{
fprintf(stderr,"\nError creating a source string\n");
return 0;
}
/* Open the capture file */
if ( (indesc= pcap_open(source, 65536, PCAP_OPENFLAG_PROMISCUOUS, 1000, NULL, errbuf) ) == NULL)
{
fprintf(stderr,"\nUnable to open the file %s.\n", source);
return 0;
}
/* get the first packet*/
res=pcap_next_ex( indesc, &pktheader, &pktdata);
if (res !=1){
printf("\nError Reading PCAP File");
return 0;
}
/* Get the packet size*/
pktsize=pktheader->len;
/* Close the input file */
pcap_close(indesc);
return pktsize;
}
Another wroking Example in Python using the wonderful SCAPY
from scapy.all import *
pkts=rdpcap("data.pcap",1) # reading only 1 packet from the file
OnePkt=pkts[0]
print len(OnePkt) # prints the length of the packet
I'm trying to write raw audio bytes to a file using AudioFileWriteBytes(). Here's what I'm doing:
void writeSingleChannelRingBufferDataToFileAsSInt16(AudioFileID audioFileID, AudioConverterRef audioConverter, ringBuffer *rb, SInt16 *holdingBuffer) {
// First, figure out which bits of audio we'll be
// writing to file from the ring buffer
UInt32 lastFreshSample = rb->lastWrittenIndex;
OSStatus status;
int numSamplesToWrite;
UInt32 numBytesToWrite;
if (lastFreshSample < rb->lastReadIndex) {
numSamplesToWrite = kNumPointsInWave + lastFreshSample - rb->lastReadIndex - 1;
}
else {
numSamplesToWrite = lastFreshSample - rb->lastReadIndex;
}
numBytesToWrite = numSamplesToWrite*sizeof(SInt16);
Then we copy the audio data (stored as floats) to a holding buffer (SInt16) that will be written directly to the file. The copying looks funky because it's from a ring buffer.
UInt32 buffLen = rb->sizeOfBuffer - 1;
for (int i=0; i < numSamplesToWrite; ++i) {
holdingBuffer[i] = rb->data[(i + rb->lastReadIndex) & buffLen];
}
Okay, now we actually try to write the audio from the SInt16 buffer "holdingBuffer" to the audio file. The NSLog will spit out an error -40, but also claims that it's writing bytes. No data is written to file.
status = AudioFileWriteBytes(audioFileID, NO, 0, &numBytesToWrite, &holdingBuffer);
rb->lastReadIndex = lastFreshSample;
NSLog(#"Error = %d, wrote %d bytes", status, numBytesToWrite);
return;
What is this error -40? By the way, everything works fine if I write straight from the ringBuffer to the file. Of course it sounds like junk, because I'm writing floats, not SInt16s, but AudioFileWriteBytes doesn't complain.
The key is to explicitly change the endianness of the incoming data to big endian. All I had to do was wrap CFSwapInt16HostToBig around my data to get:
float audioVal = rb->data[(i + rb->lastReadIndex) & buffLen];
holdingBuffer[i] = CFSwapInt16HostToBig((SInt16) audioVal );