Is is possible to configure Aldec Riviera-PRO simulator to break simulation on either $error or $warning SystemVerilog calls? If it is then how?
I don't think there's a specific config option for promoting $error or $warning to a breakpoint in Riviera-PRO, although it worth checking with their support. You do have a couple of options:
Replace $error with $fatal
Write a VPI module to overload the system tasks with custom C code
The second option would look something like this:
#include "vpi_user.h"
// System function overload on $warning and $error to stop sim
static int system_function_overload(char *userdata)
{
vpiHandle systfref, args_iter, argh;
struct t_vpi_value argval;
const char *msg = "*** NO MESSAGE PROVIDED ***";
// Obtain a handle to the argument list
systfref = vpi_handle(vpiSysTfCall, NULL);
args_iter = vpi_iterate(vpiArgument, systfref);
// Pull out the string passed in as the first argument
if (args_iter) {
argh = vpi_scan(args_iter);
argval.format = vpiStringVal;
vpi_get_value(argh, &argval);
vpi_free_object(args_iter);
msg = argval.value.str;
}
vpi_printf("BREAK sim from %s:%d with msg %s\n",
vpi_get_str(vpiFile, systfref),
vpi_get(vpiLineNo, systfref),
msg);
vpi_control(vpiStop);
return 0;
}
static void register_system_functions(void)
{
s_vpi_systf_data tfData = { vpiSysTask, vpiSysTask };
tfData.sizetf = NULL;
tfData.compiletf = system_function_compiletf;
tfData.calltf = system_function_overload;
tfData.user_data = NULL;
tfData.tfname = "$warning";
vpi_register_systf( &tfData );
tfData.tfname = "$error";
vpi_register_systf( &tfData );
}
void (*vlog_startup_routines[])(void) = {
register_system_functions,
0
};
Related
I'd like to generate logging messages from within a C function embedded in a DML method. Take the example code below where the fib() function is called from the write() method of the regs bank. The log methods available to C all require a pointer to the current device.
Is there a way to get the device that calls the embedded function? Do I need to pass the device pointer into fib()?
dml 1.2;
device simple_embedded;
parameter documentation = "Embedding C code example for"
+ " Model Builder User's Guide";
parameter desc = "example of C code";
extern int fib(int x);
bank regs {
register r0 size 4 #0x0000 {
parameter allocate = false;
parameter configuration = "none";
method write(val) {
log "info": "Fibonacci(%d) = %d.", val, fib(val);
}
method read() -> (value) {
// Must be implemented to compile
}
}
}
header %{
int fib(int x);
%}
footer %{
int fib(int x) {
SIM_LOG_INFO(1, mydev, 0, "Generating Fibonacci for %d", x);
if (x < 2) return 1;
else return fib(x-1) + fib(x-2);
}
%}
I want to log from an embedded C function.
I solved this by passing the Simics conf_object_t pointer along to C. Just like implied in the question.
So you would use:
int fib(conf_object_t *mydev, int x) {
SIM_LOG_INFO(1, mydev, 0, "Generating Fibonacci for %d", x);
}
And
method write(val) {
log "info": "Fibonacci(%d) = %d.", val, fib(dev.obj,val);
}
Jakob's answer is the right one if your purpose is to offload some computations to C code (which makes sense in many situations, like when functionality is implemented by a lib).
However, if you just want a way to pass a callback to an API that asks for a function pointer, then it is easier to keep the implementation within DML and use a method reference, like:
method init() {
SIM_add_notifier(obj, trigger_fib_notifier_type, obj, &trigger_fib,
&dev.regs.r0.val);
}
method trigger_fib(conf_object_t *_, lang_void *aux) {
value = *cast(aux, uint64 *);
local int result = fib(value);
log info: "result: %d", result;
}
method fib(int x) -> (int) {
log info: "Generating Fibonacci for %d", x;
if (x < 2) return 1;
else return fib(x-1) + fib(x-2);
}
I'm using boost::asio with ncurses for a command-line game. The game needs to draw on the screen at a fixed time interval, and other operations (e.g. networking or file operations) are also executed whenever necessary. All these things can be done with async_read()/async_write() or equivalent on boost::asio.
However, I also need to read keyboard input, which (I think) comes from stdin. The usual way to read input in ncurses is to call getch(), which can be configured to either blocking (wait until there is a character available for consumption) or non-blocking (return a sentinel value of there no characters available) mode.
Using blocking mode would necessitate running getch() on a separate thread, which doesn't play well with ncurses. Using non-blocking mode, however, would cause my application to consume CPU time spinning in a loop until the user presses their keyboard. I've read this answer, which suggests that we can add stdin to the list of file descriptors in a select() call, which would block until one of the file descriptors has new data.
Since I'm using boost::asio, I can't directly use select(). I can't call async_read, because that would consume the character, leaving getch() with nothing to read. Is there something in boost::asio like async_read, but merely checks the existence of input without consuming it?
I think you should be able to use the posix stream descriptor to watch for input on file descriptor 0:
ba::posix::stream_descriptor d(io, 0);
input_loop = [&](error_code ec) {
if (!ec) {
program.on_input();
d.async_wait(ba::posix::descriptor::wait_type::wait_read, input_loop);
}
};
There, program::on_input() would call getch() with no timeout() until it returns ERR:
struct Program {
Program() {
initscr();
ESCDELAY = 0;
timeout(0);
cbreak();
noecho();
keypad(stdscr, TRUE); // receive special keys
clock = newwin(2, 40, 0, 0);
monitor = newwin(10, 40, 2, 0);
syncok(clock, true); // automatic updating
syncok(monitor, true);
scrollok(monitor, true); // scroll the input monitor window
}
~Program() {
delwin(monitor);
delwin(clock);
endwin();
}
void on_clock() {
wclear(clock);
char buf[32];
time_t t = time(NULL);
if (auto tmp = localtime(&t)) {
if (strftime(buf, sizeof(buf), "%T", tmp) == 0) {
strncpy(buf, "[error formatting time]", sizeof(buf));
}
} else {
strncpy(buf, "[error getting time]", sizeof(buf));
}
wprintw(clock, "Async: %s", buf);
wrefresh(clock);
}
void on_input() {
for (auto ch = getch(); ch != ERR; ch = getch()) {
wprintw(monitor, "received key %d ('%c')\n", ch, ch);
}
wrefresh(monitor);
}
WINDOW *monitor = nullptr;
WINDOW *clock = nullptr;
};
With the following main program you'd run it for 10 seconds (because Program doesn't yet know how to exit):
int main() {
Program program;
namespace ba = boost::asio;
using boost::system::error_code;
using namespace std::literals;
ba::io_service io;
std::function<void(error_code)> input_loop, clock_loop;
// Reading input when ready on stdin
ba::posix::stream_descriptor d(io, 0);
input_loop = [&](error_code ec) {
if (!ec) {
program.on_input();
d.async_wait(ba::posix::descriptor::wait_type::wait_read, input_loop);
}
};
// For fun, let's also update the time
ba::high_resolution_timer tim(io);
clock_loop = [&](error_code ec) {
if (!ec) {
program.on_clock();
tim.expires_from_now(100ms);
tim.async_wait(clock_loop);
}
};
input_loop(error_code{});
clock_loop(error_code{});
io.run_for(10s);
}
This works:
Full Listing
#include <boost/asio.hpp>
#include <boost/asio/posix/descriptor.hpp>
#include <iostream>
#include "ncurses.h"
#define CTRL_R 18
#define CTRL_C 3
#define TAB 9
#define NEWLINE 10
#define RETURN 13
#define ESCAPE 27
#define BACKSPACE 127
#define UP 72
#define LEFT 75
#define RIGHT 77
#define DOWN 80
struct Program {
Program() {
initscr();
ESCDELAY = 0;
timeout(0);
cbreak();
noecho();
keypad(stdscr, TRUE); // receive special keys
clock = newwin(2, 40, 0, 0);
monitor = newwin(10, 40, 2, 0);
syncok(clock, true); // automatic updating
syncok(monitor, true);
scrollok(monitor, true); // scroll the input monitor window
}
~Program() {
delwin(monitor);
delwin(clock);
endwin();
}
void on_clock() {
wclear(clock);
char buf[32];
time_t t = time(NULL);
if (auto tmp = localtime(&t)) {
if (strftime(buf, sizeof(buf), "%T", tmp) == 0) {
strncpy(buf, "[error formatting time]", sizeof(buf));
}
} else {
strncpy(buf, "[error getting time]", sizeof(buf));
}
wprintw(clock, "Async: %s", buf);
wrefresh(clock);
}
void on_input() {
for (auto ch = getch(); ch != ERR; ch = getch()) {
wprintw(monitor, "received key %d ('%c')\n", ch, ch);
}
wrefresh(monitor);
}
WINDOW *monitor = nullptr;
WINDOW *clock = nullptr;
};
int main() {
Program program;
namespace ba = boost::asio;
using boost::system::error_code;
using namespace std::literals;
ba::io_service io;
std::function<void(error_code)> input_loop, clock_loop;
// Reading input when ready on stdin
ba::posix::stream_descriptor d(io, 0);
input_loop = [&](error_code ec) {
if (!ec) {
program.on_input();
d.async_wait(ba::posix::descriptor::wait_type::wait_read, input_loop);
}
};
// For fun, let's also update the time
ba::high_resolution_timer tim(io);
clock_loop = [&](error_code ec) {
if (!ec) {
program.on_clock();
tim.expires_from_now(100ms);
tim.async_wait(clock_loop);
}
};
input_loop(error_code{});
clock_loop(error_code{});
io.run_for(10s);
}
According to some parts of ECL manual, necessary part of the library (that has been compiled by lisp) initialisation in C program is performing its initialisation as:
ecl_init_module(NULL, init_func_for_library);
In all examples provided first parameter is NULL.
What other values can it take and to what end? Certainly the parameter itself should have some meaning.
NB. In other parts of the manual, for performing initialisation, it is recommended to use read_VV instead. What does that do?
Inspecting the source code, we can see that NULL is bound to a variable named block; when it is NULL, a default, empty codeblock is used instead:
cl_object
ecl_init_module(cl_object block, void (*entry_point)(cl_object))
{
...
if (block == NULL)
block = ecl_make_codeblock();
...
}
Code blocks look like some sort of context/environment structures:
cl_object
ecl_make_codeblock()
{
cl_object block = ecl_alloc(t_codeblock);
block = ecl_alloc_object(t_codeblock);
block->cblock.self_destruct = 0;
block->cblock.locked = 0;
block->cblock.handle = NULL;
block->cblock.data = NULL;
block->cblock.data_size = 0;
block->cblock.temp_data = NULL;
block->cblock.temp_data_size = 0;
block->cblock.data_text = NULL;
block->cblock.next = ECL_NIL;
block->cblock.name = ECL_NIL;
block->cblock.links = ECL_NIL;
block->cblock.cfuns_size = 0;
block->cblock.cfuns = NULL;
block->cblock.source = ECL_NIL;
block->cblock.error = ECL_NIL;
block->cblock.refs = ecl_make_fixnum(0);
si_set_finalizer(block, ECL_T);
return block;
}
I guess in most cases, passing NULL is sufficient. Presumably you could call ecl_init_module with an existing code block to share to some state with another module; without a better understanding of how the interpreter works, this is however risky.
I would like to implement my own OPC DA client (versions 2.02, 2.05a, 3.00) from scratch but without using any third-party. Also I would like to make use of OPCEnum.exe service to get a list of installed OPC servers. Is there any kind of document that explains detailed and step by step the process to implement an OPC client?
I have a c# implementation but actually it's hard to fit it in here. I'll try to summarize the steps required.
Mostly you need to have OpcRcw.Comn.dll and OpcRcw.Da.dll from the OPC Core Components Redistributable package downloable for free from Opcfoundation.org. Once installed, the files are located in C:\Windows\assembly\GAC_MSIL. Create a reference in your project.
About coding, this is what you should do (there are three objects you want to implement, Server, Group and Item):
Let's start with server:
Type typeofOPCserver = Type.GetTypeFromProgID(serverName, computerName, true);
m_opcServer = (IOPCServer)Activator.CreateInstance(typeofOPCserver);
m_opcCommon = (IOPCCommon)m_opcServer;
IConnectionPointContainer icpc = (IConnectionPointContainer)m_opcServer;
Guid sinkGUID = typeof(IOPCShutdown).GUID;
icpc.FindConnectionPoint(ref sinkGUID, out m_OPCCP);
m_OPCCP.Advise(this, out m_cookie_CP);
I've striped a LOT of checking to fit it in here, take it as a sample...
Then you need a method on server to add groups:
// Parameter as following:
// [in] active, so do OnDataChange callback
// [in] Request this Update Rate from Server
// [in] Client Handle, not necessary in this sample
// [in] No time interval to system UTC time
// [in] No Deadband, so all data changes are reported
// [in] Server uses english language to for text values
// [out] Server handle to identify this group in later calls
// [out] The answer from Server to the requested Update Rate
// [in] requested interface type of the group object
// [out] pointer to the requested interface
m_opcServer.AddGroup(m_groupName, Convert.ToInt32(m_isActive), m_reqUpdateRate, m_clientHandle, pTimeBias, pDeadband, m_LocaleID, out m_serverHandle, out m_revUpdateRate, ref iid, out objGroup);
// Get our reference from the created group
m_OPCGroupStateMgt = (IOPCGroupStateMgt)objGroup;
Finally you need to create items:
m_OPCItem = (IOPCItemMgt)m_OPCGroupStateMgt;
m_OPCItem.AddItems(itemList.Length, GetAllItemDefs(itemList), out ppResults, out ppErrors);
Where itemlist is an array of OPCITEMDEF[]. I build the above using GetAllItemDefs from a structure of mine.
private static OPCITEMDEF[] GetAllItemDefs(params OpcItem[] opcItemList)
{
OPCITEMDEF[] opcItemDefs = new OPCITEMDEF[opcItemList.Length];
for (int i = 0; i < opcItemList.Length; i++)
{
OpcItem opcItem = opcItemList[i];
opcItemDefs[i].szAccessPath = "";
opcItemDefs[i].bActive = Convert.ToInt32(opcItem.IsActive);
opcItemDefs[i].vtRequestedDataType = Convert.ToInt16(opcItem.ItemType, CultureInfo.InvariantCulture);
opcItemDefs[i].dwBlobSize = 0;
opcItemDefs[i].pBlob = IntPtr.Zero;
opcItemDefs[i].hClient = opcItem.ClientHandle;
opcItemDefs[i].szItemID = opcItem.Id;
}
return opcItemDefs;
}
Finally, about enumerating Servers, I use this two functions:
/// <summary>
/// Enumerates hosts that may be accessed for server discovery.
/// </summary>
[SecurityPermission(SecurityAction.LinkDemand, UnmanagedCode = true)]
public string[] EnumerateHosts()
{
IntPtr pInfo;
int entriesRead = 0;
int totalEntries = 0;
int result = NetServerEnum(
IntPtr.Zero,
LEVEL_SERVER_INFO_100,
out pInfo,
MAX_PREFERRED_LENGTH,
out entriesRead,
out totalEntries,
SV_TYPE_WORKSTATION | SV_TYPE_SERVER,
IntPtr.Zero,
IntPtr.Zero);
if (result != 0)
throw new ApplicationException("NetApi Error = " + String.Format("0x{0,0:X}", result));
string[] computers = new string[entriesRead];
IntPtr pos = pInfo;
for (int ii = 0; ii < entriesRead; ii++)
{
SERVER_INFO_100 info = (SERVER_INFO_100)Marshal.PtrToStructure(pos, typeof(SERVER_INFO_100));
computers[ii] = info.sv100_name;
pos = (IntPtr)(pos.ToInt32() + Marshal.SizeOf(typeof(SERVER_INFO_100)));
}
NetApiBufferFree(pInfo);
return computers;
}
/// <summary>
/// Returns a list of servers that support the specified specification on the specified host.
/// </summary>
[SecurityPermission(SecurityAction.LinkDemand, UnmanagedCode = true)]
public string[] GetAvailableServers(Specification specification)
{
lock (this)
{
// connect to the server.
ArrayList servers = new ArrayList();
MULTI_QI[] results = new MULTI_QI[1];
GCHandle hIID = GCHandle.Alloc(IID_IUnknown, GCHandleType.Pinned);
results[0].iid = hIID.AddrOfPinnedObject();
results[0].pItf = null;
results[0].hr = 0;
try
{
// create an instance.
Guid srvid = CLSID;
CoCreateInstanceEx(srvid, null, CLSCTX.CLSCTX_LOCAL_SERVER, IntPtr.Zero, 1, results);
m_server = (IOPCServerList2)results[0].pItf;
// convert the interface version to a guid.
Guid catid = new Guid(specification.ID);
// get list of servers in the specified specification.
IOPCEnumGUID enumerator = null;
m_server.EnumClassesOfCategories(1, new Guid[] { catid }, 0, null, out enumerator);
// read clsids.
Guid[] clsids = ReadClasses(enumerator);
// release enumerator
if (enumerator != null && enumerator.GetType().IsCOMObject)
Marshal.ReleaseComObject(enumerator);
// fetch class descriptions.
foreach (Guid clsid in clsids)
{
try
{
string url = CreateUrl(specification, clsid);
servers.Add(url);
}
catch (Exception) { }
}
}
catch
{
}
finally
{
if (hIID.IsAllocated) hIID.Free();
if (m_server != null && m_server.GetType().IsCOMObject)
Marshal.ReleaseComObject(m_server);
}
return (string[])servers.ToArray(typeof(string));
}
}
I know I've striped a lot but maybe it can still help you ;)
Please mark the answer as correct if you think I've been clear ;)
Kind Regards,
D.
#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
#include<sys/sem.h>
#include<sys/ipc.h>
int sem_id;
void update_file(int number)
{
struct sembuf sem_op;
FILE* file;
printf("Inside Update Process\n");
/* wait on the semaphore, unless it's value is non-negative. */
sem_op.sem_num = 0;
sem_op.sem_op = -1; /* <-- Amount by which the value of the semaphore is to be decreased */
sem_op.sem_flg = 0;
semop(sem_id, &sem_op, 1);
/* we "locked" the semaphore, and are assured exclusive access to file. */
/* manipulate the file in some way. for example, write a number into it. */
file = fopen("file.txt", "a+");
if (file) {
fprintf(file, " \n%d\n", number);
fclose(file);
}
/* finally, signal the semaphore - increase its value by one. */
sem_op.sem_num = 0;
sem_op.sem_op = 1;
sem_op.sem_flg = 0;
semop( sem_id, &sem_op, 1);
}
void write_file(char* contents)
{
printf("Inside Write Process\n");
struct sembuf sem_op;
sem_op.sem_num = 0;
sem_op.sem_op = -1;
sem_op.sem_flg = 0;
semop( sem_id, &sem_op, 1);
FILE *file = fopen("file.txt","w");
if(file)
{
fprintf(file,contents);
fclose(file);
}
sem_op.sem_num = 0;
sem_op.sem_op = 1;
sem_op.sem_flg = 0;
semop( sem_id, &sem_op, 1);
}
int main()
{
//key_t key = ftok("file.txt",'E');
sem_id = semget( IPC_PRIVATE, 1, 0600 | IPC_CREAT);
/*here 100 is any arbit number to be assigned as the key of the
semaphore,1 is the number of semaphores in the semaphore set, */
if(sem_id == -1)
{
perror("main : semget");
exit(1);
}
int rc = semctl( sem_id, 0, SETVAL, 1);
pid_t u = fork();
if(u == 0)
{
update_file(100);
exit(0);
}
else
{
wait();
}
pid_t w = fork();
if(w == 0)
{
write_file("Hello!!");
exit(0);
}
else
{
wait();
}
}
If I run the above code as a c code, the write_file() function is called after the update_file () function
Whereas if I run the same code as a c++ code, the order of execution is reverse... why is it so??
Just some suggestions, but it looks to me like it could be caused by a combination of things:
The wait() call is supposed to take a pointer argument (that can
be NULL). Compiler should have caught this, but you must be picking
up another definition somewhere that permits your syntax. You are
also missing an include for sys/wait.h. This might be why the
compiler isn't complaining as I'd expect it to.
Depending on your machine/OS configuration the fork'd process may
not get to run until after the parent yields. Assuming the "wait()"
you are calling isn't working the way we would be expecting, it is
possible for the parent to execute completely before the children
get to run.
Unfortunately, I wasn't able to duplicate the same temporal behavior. However, when I generated assembly files for each of the two cases (C & C++), I noticed that the C++ version is missing the "wait" system call, but the C version is as I would expect. To me, this suggests that somewhere in the C++ headers this special version without an argument is being #defined out of the code. This difference could be the reason behind the behavior you are seeing.
In a nutshell... add the #include, and change your wait calls to "wait(0)"