I was playing around with some multithreading example code shown below (taken from from http://www.bogotobogo.com/cplusplus/multithreading_win32A.php) using codeblocks (build option was set to c++11).
#include <windows.h>
#include <iostream>
#include <stdio.h>
DWORD WINAPI myThread(LPVOID lpParameter)
{
unsigned int& myCounter = *((unsigned int*)lpParameter);
while(myCounter < 0xFFFFFFFF) ++myCounter;
return 0;
}
int main(int argc, char* argv[])
{
using namespace std;
unsigned int myCounter = 0;
DWORD myThreadID;
HANDLE myHandle = CreateThread(0, 0, myThread, &myCounter, 0, &myThreadID);
char myChar = ' ';
while(myChar != 'q') {
cout << myCounter << endl;
myChar = getchar();
}
CloseHandle(myHandle);
return 0;
}
When I built the project the "cwchar" file was opened and I got the huge list of "has not declared" errors shown below. I'm not sure what's wrong here, any ideas?
||=== Build: Debug in TEST2 (compiler: GNU GCC Compiler) ===|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|177|error: '::wcscat' has not been declared|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|178|error: '::wcscmp' has not been declared|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|179|error: '::wcscoll' has not been declared|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|180|error: '::wcscpy' has not been declared|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|181|error: '::wcscspn' has not been declared|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|183|error: '::wcslen' has not been declared|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|184|error: '::wcsncat' has not been declared|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|185|error: '::wcsncmp' has not been declared|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|186|error: '::wcsncpy' has not been declared|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|188|error: '::wcsspn' has not been declared|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|193|error: '::wcstok' has not been declared|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|196|error: '::wcsxfrm' has not been declared|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|204|error: '::wcschr' has not been declared|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|205|error: '::wcspbrk' has not been declared|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|206|error: '::wcsrchr' has not been declared|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|207|error: '::wcsstr' has not been declared|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar||In function 'wchar_t* std::wcschr(wchar_t*, wchar_t)':|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|213|error: invalid conversion from 'const wchar_t*' to 'wchar_t*' [-fpermissive]|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|212|note: initializing argument 1 of 'wchar_t* std::wcschr(wchar_t*, wchar_t)'|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar||In function 'wchar_t* std::wcspbrk(wchar_t*, const wchar_t*)':|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|217|error: invalid conversion from 'const wchar_t*' to 'wchar_t*' [-fpermissive]|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|216|note: initializing argument 1 of 'wchar_t* std::wcspbrk(wchar_t*, const wchar_t*)'|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar||In function 'wchar_t* std::wcsrchr(wchar_t*, wchar_t)':|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|221|error: invalid conversion from 'const wchar_t*' to 'wchar_t*' [-fpermissive]|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|220|note: initializing argument 1 of 'wchar_t* std::wcsrchr(wchar_t*, wchar_t)'|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar||In function 'wchar_t* std::wcsstr(wchar_t*, const wchar_t*)':|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|225|error: invalid conversion from 'const wchar_t*' to 'wchar_t*' [-fpermissive]|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\cwchar|224|note: initializing argument 1 of 'wchar_t* std::wcsstr(wchar_t*, const wchar_t*)'|
c:\mingw\lib\gcc\mingw32\5.3.0\include\c++\bits\char_traits.h|358|error: 'wcslen' was not declared in this scope|
||=== Build failed: 21 error(s), 0 warning(s) (0 minute(s), 1 second(s)) ===|
Please read the error message, you have a typo in your code:
HANDLE myHandle = CreateThread(0, 0, myThread, &myCounter;, 0, &myThreadID;);
Remove the extra ';' from this line and you should be fine!
I fixed the problem by moving the #include <windows.h> line from it's original position to below the #include <stdio.h> line. Includes now look like this:
#include <iostream>
#include <stdio.h>
#include <windows.h>
Don't ask my why it worked lol.
Related
I wrote a simple program to attach to execve system call with a kprobe, but I am unable to see the relevant output.
Here is my one.c (BPF program):
#include <errno.h>
#include <bpf/bpf.h>
#include <stdio.h>
#include <string.h>
#include "bpf_load.h"
#include "bpf_util.h"
#include "libbpf.h"
#define SEC(NAME) __attribute__((section(NAME), used))
SEC("kprobe/execve")
int bpf_prog1(struct pt_regs *ctx)
{
char m[]="hello world";
bpf_trace_printk(m,sizeof(m));
return 0;
}
char _license[] SEC("license") = "GPL";
bpf_load.c (user space loader):
#include "bpf_load.h"
#include <stdio.h>
#include <linux/bpf.h>
#include <sys/resource.h>
int main(int argc, char **argv) {
if (load_bpf_file("one.o")) {
printf("%s", bpf_log_buf);
return 1;
}
return 0;
}
And the Makefile:
CLANG = clang
EXECABLE = monitor-exec
BPFCODE = one
BPFTOOLS = /kernel-src/samples/bpf
BPFLOADER = $(BPFTOOLS)/bpf_load.c
INCLUDE += -I/kernel-src/samples/bpf
INCLUDE += -I/kernel-src/tools/lib
CCINCLUDE += -I/kernel-src/tools/testing/selftests/bpf
CCINCLUDE += -I/kernel-src/tools/lib/bpf
CCINCLUDE += ${INCLUDE}
LOADINCLUDE += -I/kernel-src/tools/include
LOADINCLUDE += -I/kernel-src/tools/perf
LOADINCLUDE += ${INCLUDE}
LIBRARY_PATH = -L/usr/local/lib64
BPFSO = -lbpf
.PHONY: clean bpfload build
clean:
rm -f *.o *.so $(EXECABLE)
build: ${BPFCODE.c} ${BPFLOADER}
$(CLANG) -O2 -DHAVE_ATTR_TEST=0 -target bpf -c $(BPFCODE:=.c) $(CCINCLUDE) -o ${BPFCODE:=.o}
bpfload: build
clang -o $(EXECABLE) -DHAVE_ATTR_TEST=0 -lelf $(LOADINCLUDE) $(LIBRARY_PATH) $(BPFSO) \
$(BPFLOADER) loader.c
$(EXECABLE): bpfload
.DEFAULT_GOAL := $(EXECABLE)
As of now I don't get any errors from the Makefile.
I am getting the following output when I execute ./monitor-exec
invalid relo for insn[6].code 0x85
bpf_load_program() err=22
last insn is not an exit or jmp
processed 0 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
last insn is not an exit or jmp
processed 0 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
I am unable to understand what I am doing wrong. I am just attaching a kprobe and that should print hello world when that system call occurs.
In your eBPF program:
#include <errno.h>
#include <bpf/bpf.h>
#include <stdio.h>
#include <string.h>
#include "bpf_load.h"
#include "bpf_util.h"
#include "libbpf.h"
#define SEC(NAME) __attribute__((section(NAME), used))
SEC("kprobe/execve")
int bpf_prog1(struct pt_regs *ctx)
{
char m[]="hello world";
bpf_trace_printk(m,sizeof(m));
return 0;
}
You use bpf_trace_printk() correctly (although you might want to add a \n at the end of your message or your output will be messy), but it turns out none of the files you include contains the definition for this helper.
bpf_trace_printk() is compiled as part of the kernel and won't ever be compiled into your BPF object file. When trying to load your program, the function load_bpf_file() does a relocation step where it places the number associated to bpf_trace_printk() (in user API) in the relevant instruction of the eBPF bytecode.
But it needs to find this number somewhere. It is defined in header linux/bpf.h (pulled from several of your includes) as FN(trace_printk) (some macro magic going on), resulting de facto in a #define BPF_FUNC_trace_prink 6. But you need to tell your loading function that it corresponds to the bpf_trace_prink() you're calling!
Two solutions:
Manually declare it:
static int (*bpf_trace_printk)(const char *fmt, int fmt_size, ...) =
(void *) BPF_FUNC_trace_printk;
Or add a header that contains it, e.g. tools/lib/bpf/bpf_helpers.h in kernel repo. In your case:
#include <bpf/bpf_helpers.h>
(Note that this header is generated when compiling libbpf, it is not present in the repository by default.)
I try to run a sample code as below. The ioctl returned -1 and the error is "Invalid argument". What I know is that ioctl here is used to check the state of shift. Does ioctl return success when the shift is pressed? If not, how do I know the shift is pressed by using ioctl?
Plus, it's under xterm.
#include <stdio.h>
#include <stdlib.h>
#include <sys/ioctl.h>
int main()
{
char shift_state;
shift_state = 6;
if (ioctl(0, TIOCLINUX, &shift_state) < 0) {
perror("ioctl TIOCLINUX 6 (get shift state)");
exit(1);
}
printf("%x\n", shift_state);
return 0;
}
I have tried to "simplify" a nice piece of example code, the hyperlink to the code is at the end of this message, to specify the directory string instead of passing it as a command line argument. The simplified code compiles and executes, but the filename and size are not what I expect: the file name appears to be a hex number, and the nFileSize.High is larger than the nFileSize.Low (the actual file sizes range from 0 to 100Mb). I think my type casting may have introduced errors. Any suggestions?
#include "stdafx.h"
#include <iostream>
#include <fstream>
#include <string>
#include <cctype>
#include <bitset>
#include <sstream>
#include <windows.h>
#include <tchar.h>
#include <stdio.h>
#include <strsafe.h>
#pragma comment(lib, "User32.lib")
using namespace std;
using namespace System; //set common language runtime support to /clr
int main()
{
WIN32_FIND_DATA ffd;
LARGE_INTEGER filesize;
//TCHAR szDir[MAX_PATH];
//size_t length_of_arg;
HANDLE hFind = INVALID_HANDLE_VALUE;
//DWORD dwError=0;
finstr = "C:\\Users\\MyName\\Documents\\Visual Studio 2010\\Projects\\Data Analysis\\Data Folder\\*";
//Just evaluate the first file before looping over all files
hFind = FindFirstFile((wchar_t*)(finstr.c_str()), &ffd);
wstring wsfname(ffd.cFileName);
string newtemp(wsfname.begin(), wsfname.end());
cout << "1st fname = " << ffd.cFileName << " newtemp = "<< newtemp << " nFSizeLo = "<< ffd.nFileSizeLow << " nFSizeHi = "<< ffd.nFileSizeHigh << "\n";
FindClose(hFind);
return 0;
}
Link to original example from Microsoft
https://msdn.microsoft.com/en-us/library/windows/desktop/aa365200(d=printer,v=vs.85).aspx
I've been banging my head against a wall trying to understand how to use CGAL's Circular Kernel to calculate the intersection(s) between a line segment (Line_Arc_2) and a Circle (Circle_2). Unfortunately there isn't much in the way of example code for the Circular Kernel, and I'm not finding the reference manual much help.
Here is code that I thought would work, but right now it won't even compile (Mac OS 10.9 using the latest system compiler):
#include <vector>
#include <iterator>
#include <CGAL/Exact_circular_kernel_2.h>
#include <CGAL/Circular_kernel_intersections.h>
#include <CGAL/intersections.h>
#include <CGAL/result_of.h>
#include <CGAL/iterator.h>
#include <CGAL/point_generators_2.h>
#include <boost/bind.hpp>
typedef CGAL::Exact_circular_kernel_2 CircK;
typedef CGAL::Point_2<CircK> Pt2;
typedef CGAL::Circle_2<CircK> Circ2;
typedef CGAL::Line_arc_2<CircK> LineArc2;
typedef CGAL::cpp11::result_of<CircK::Intersect_2(Circ2,LineArc2)>::type Res;
int main(){
int n = 0;
Circ2 c = Circ2(Pt2(1,0), Pt2(0,1), Pt2(-1, 0));
LineArc2 l = LineArc2( Pt2(0,-2), Pt2(0,2) );
std::vector<Res> result;
CGAL::intersection(c, l, std::back_inserter(result));
return 0;
}
I get an error on the result_of line: "error: no type named 'result_type' in...", and a second error that "no viable overloaded '='" is available for the intersection line.
Also, since this would probably be the follow up question once this is working: how do I actually get at the intersection points that are put in the vector? CGAL's documentation suggests to me "result" should contain pairs of a Circular_arc_point_2 and an unsigned int representing its multiplicity. Is this what I will actually get in this case? More generally, does anyone know a good tutorial for using the Circular Kernel and Spherical Kernel intersection routines?
Thanks!
So it seems that result_of doesn't work here, despite being suggested in the CGAL reference manual for the CircularKernel's intersection function.
Here is a different version that seems to work and can properly handle the output:
#include <vector>
#include <iterator>
#include <CGAL/Exact_circular_kernel_2.h>
#include <CGAL/Circular_kernel_intersections.h>
#include <CGAL/intersections.h>
#include <CGAL/iterator.h>
typedef CGAL::Exact_circular_kernel_2 CircK;
typedef CGAL::Point_2<CircK> Pt2;
typedef CGAL::Circle_2<CircK> Circ2;
typedef CGAL::Line_arc_2<CircK> LineArc2;
typedef std::pair<CGAL::Circular_arc_point_2<CircK>, unsigned> IsectOutput;
using namespace std;
int main(){
int n = 0;
Circ2 c = Circ2(Pt2(1.0,0.0), Pt2(0.0,1.0), Pt2(-1.0, 0.0));
LineArc2 l = LineArc2( Pt2(0.0,-2.0), Pt2(0.0,2.0) );
std::vector<IsectOutput> output;
typedef CGAL::Dispatch_output_iterator< CGAL::cpp11::tuple<IsectOutput>,
CGAL::cpp0x::tuple< std::back_insert_iterator<std::vector<IsectOutput> > > > Dispatcher;
Dispatcher disp = CGAL::dispatch_output<IsectOutput>( std::back_inserter(output) );
CGAL::intersection(l, c, disp);
cout << output.size() << endl;
for( const auto& v : output ){
cout << "Point: (" << CGAL::to_double( v.first.x() ) << ", " << CGAL::to_double( v.first.y() ) << "), Mult: "
<< v.second << std::endl;
}
return 0;
}
result_of is working but the operator you are asking for does not exist, you are missing the output iterator.
However, I agree the doc is misleading. I'll try to fix it.
The following code is working fine:
#include <vector>
#include <iterator>
#include <CGAL/Exact_circular_kernel_2.h>
#include <CGAL/Circular_kernel_intersections.h>
#include <CGAL/intersections.h>
#include <CGAL/result_of.h>
#include <CGAL/iterator.h>
#include <CGAL/point_generators_2.h>
#include <boost/bind.hpp>
typedef CGAL::Exact_circular_kernel_2 CircK;
typedef CGAL::Point_2<CircK> Pt2;
typedef CGAL::Circle_2<CircK> Circ2;
typedef CGAL::Line_arc_2<CircK> LineArc2;
typedef boost::variant<std::pair<CGAL::Circular_arc_point_2<CircK>, unsigned> > InterRes;
typedef CGAL::cpp11::result_of<CircK::Intersect_2(Circ2,LineArc2,std::back_insert_iterator<std::vector<InterRes> >)>::type Res;
int main(){
Circ2 c = Circ2(Pt2(1,0), Pt2(0,1), Pt2(-1, 0));
LineArc2 l = LineArc2( Pt2(0,-2), Pt2(0,2) );
std::vector<InterRes> result;
CGAL::intersection(c, l, std::back_inserter(result));
return 0;
}
When I compile this code in Visual C++, I got the below error. Can help me solve this issue..
DWORD nBufferLength = MAX_PATH;
char szCurrentDirectory[MAX_PATH + 1];
GetCurrentDirectory(nBufferLength, szCurrentDirectory);
szCurrentDirectory[MAX_PATH +1 ] = '\0';
Error message:
Error 5 error C2664: 'GetCurrentDirectoryW' : cannot convert parameter 2 from 'char [261]' to 'LPWSTR' c:\car.cpp
Your program is configured to be compiled as unicode. Thats why GetCurrentDirectory is GetCurrentDirectoryW, which expects a LPWSTR (wchar_t*).
GetCurrentDirectoryW expects a wchar_t instead of char array. You can do this using TCHAR, which - like GetCurrentDirectory - depends on the unicode setting and always represents the appropriate character type.
Don't forget to prepend your '\0' with an L in order to make the char literal unicode, too!
It seems you have define UNICODE, _UNICODE compiler flags. In that case, you need to change the type of szCurrentDirectory from char to TCHAR.
Headers:
#include <iostream>
#include <fstream>
#include <direct.h>
#include <string.h>
#include <windows.h> //not sure
Function to get current directory:
std::string getCurrentDirectoryOnWindows()
{
const unsigned long maxDir = 260;
wchar_t currentDir[maxDir];
GetCurrentDirectory(maxDir, currentDir);
std::wstring ws(currentDir);
std::string current_dir(ws.begin(), ws.end());
return std::string(current_dir);
}
To call function:
std::string path = getCurrentDirectoryOnWindows(); //Output like: C:\Users\NameUser\Documents\Programming\MFC Program 5
To make dir (Folder) in current directory:
std::string FolderName = "NewFolder";
std::string Dir1 = getCurrentDirectoryOnWindows() + "\\" + FolderName;
_mkdir(Dir1.c_str());
This works for me in MFC C++.