7 #include "thread_util.h"
17 * @param executablePath - path to the program that will be run
19 * Creates two pipes - one for each direction between the parent process and the AI program
21 * The child process closes unused sides of the pipe, and then calls exec to replace itself with the AI program
22 * The parent process closes unused sides of the pipe, and sets up member variables - associates streams with the pipe fd's for convenience.
24 Program::Program(const char * executablePath) : input(NULL), output(NULL), pid(0), paused(false)
30 if (executablePath[0] != '"')
31 args.push_back((char*)executablePath);
33 args.push_back((char*)(executablePath)+1);
37 token = strstr(args[args.size()-1], " ");
48 while (*token != '\0' && iswspace(*token));
50 if (*token != '\0' && !iswspace(*token))
52 args.push_back(token);
57 while (token != NULL);
59 char ** arguments = new char*[args.size()+2];
60 for (unsigned int i=0; i < args.size(); ++i)
61 arguments[i] = args[i];
63 //See if file exists and is executable...
64 if (access(executablePath, X_OK) != 0)
70 int readPipe[2]; int writePipe[2];
71 assert(pipe(readPipe) == 0);
72 assert(pipe(writePipe) == 0);
77 close(readPipe[0]); //close end that parent reads from
78 close(writePipe[1]); //close end that parent writes to
80 //TODO: Fix possible bug here if the process is already a daemon
81 assert(writePipe[0] != 0 && readPipe[1] != 1);
82 dup2(writePipe[0],0); close(writePipe[0]); //pipe end child reads from goes to STDIN
83 dup2(readPipe[1], 1); close(readPipe[1]); //pipe end child writes to goes to STDOUT
85 //TODO: Somehow force the exec'd process to be unbuffered
86 setbuf(stdin, NULL); //WARNING: These lines don't appear to have any affect
87 setbuf(stdout, NULL); //You should add them at the start of the wrapped program.
88 //If your wrapped program is not written in C/C++, you will probably have a problem
91 if (access(executablePath, X_OK) == 0) //Check we STILL have permissions to start the file
92 execv(executablePath,arguments); ///Replace process with desired executable
94 fprintf(stderr, "Program::Program - Could not run program \"%s\"!\n", executablePath);
95 exit(EXIT_FAILURE); //We will probably have to terminate the whole program if this happens
99 close(writePipe[0]); //close end that child writes to
100 close(readPipe[1]); //close end that child reads from
102 input = fdopen(readPipe[0],"r"); output = fdopen(writePipe[1],"w");
104 setbuf(output, NULL);
111 * Writes EOF to the wrapped program and then closes all streams
112 * Kills the wrapped program if it does not exit within 1 second.
116 if (Running()) //Check if the process created is still running...
118 //fputc(EOF, output); //If it was, tell it to stop with EOF
120 TimerThread timer(2); //Wait for 2 seconds
122 while (!timer.Finished())
142 * Forces the program to pause by sending SIGSTOP
143 * Program can be resumed by calling Continue() (which sends SIGCONT)
144 * @returns true if the program could be paused, false if it couldn't (probably because it wasn't running)
146 bool Program::Pause()
148 if (pid > 0 && kill(pid,SIGSTOP) == 0)
157 * Causes a paused program to continue
158 * @returns true if the program could be continued, false if it couldn't (probably because it wasn't running)
160 bool Program::Continue()
162 if (pid > 0 && kill(pid,SIGCONT) == 0)
171 * @returns true iff the program is paused
173 bool Program::Paused() const
180 * Sends a message to the wrapped AI program
181 * WARNING: Always prints a new line after the message (so don't include a new line)
182 * This is because everything is always line buffered.
183 * @returns true if the message was successfully sent; false if it was not (ie: the process was not running!)
185 bool Program::SendMessage(const char * print, ...)
187 if (!Running()) //Is the process running...
193 if (vfprintf(output, print, ap) < 0 || fprintf(output, "\n") < 0)
208 * Retrieves a message from the wrapped AI program, waiting a maximum amount of time
209 * @param buffer - C++ string to store the resultant message in
210 * @param timeout - Maximum amount of time to wait before failure. If timeout <= 0, then GetMessage will wait indefinately.
211 * @returns true if the response was recieved within the specified time, false if it was not, or an EOF was recieved, or the process was not running.
213 bool Program::GetMessage(string & buffer, double timeout)
215 if (!Running() || timeout == 0)
218 assert(&buffer != NULL);
219 GetterThread getterThread(input, buffer);
220 assert(&(getterThread.buffer) != NULL);
222 TimerThread timerThread(timeout*1000000);
224 getterThread.Start();
229 while (!getterThread.Finished())
231 if (timeout > 0 && timerThread.Finished())
245 if (buffer.size() == 1 && buffer[0] == EOF)
253 * Returns true iff the process is running
254 * @returns what I just said, fool
256 bool Program::Running() const
258 return (pid > 0 && kill(pid,0) == 0);