7 #include "thread_util.h"
18 * @param executablePath - path to the program that will be run
20 * Creates two pipes - one for each direction between the parent process and the AI program
22 * The child process closes unused sides of the pipe, and then calls exec to replace itself with the AI program
23 * The parent process closes unused sides of the pipe, and sets up member variables - associates streams with the pipe fd's for convenience.
25 Program::Program(const char * executablePath) : input(NULL), output(NULL), pid(0), paused(false)
31 if (executablePath[0] != '"')
32 args.push_back((char*)executablePath);
34 args.push_back((char*)(executablePath)+1);
38 token = strstr(args[args.size()-1], " ");
49 while (*token != '\0' && iswspace(*token));
51 if (*token != '\0' && !iswspace(*token))
53 args.push_back(token);
58 while (token != NULL);
60 char ** arguments = NULL;
63 arguments = new char*[args.size()+2];
64 for (unsigned int i=0; i < args.size(); ++i)
65 arguments[i] = args[i];
67 //See if file exists and is executable...
68 if (access(executablePath, X_OK) != 0)
74 int readPipe[2]; int writePipe[2];
75 assert(pipe(readPipe) == 0);
76 assert(pipe(writePipe) == 0);
81 close(readPipe[0]); //close end that parent reads from
82 close(writePipe[1]); //close end that parent writes to
84 //TODO: Fix possible bug here if the process is already a daemon
85 assert(writePipe[0] != 0 && readPipe[1] != 1);
86 dup2(writePipe[0],0); close(writePipe[0]); //pipe end child reads from goes to STDIN
87 dup2(readPipe[1], 1); close(readPipe[1]); //pipe end child writes to goes to STDOUT
89 //TODO: Somehow force the exec'd process to be unbuffered
90 setbuf(stdin, NULL); //WARNING: These lines don't appear to have any affect
91 setbuf(stdout, NULL); //You should add them at the start of the wrapped program.
92 //If your wrapped program is not written in C/C++, you will probably have a problem
95 if (access(executablePath, X_OK) == 0) //Check we STILL have permissions to start the file
97 execv(executablePath,arguments); ///Replace process with desired executable
99 perror("execv error:\n");
100 fprintf(stderr, "Program::Program - Could not run program \"%s\"!\n", executablePath);
101 exit(EXIT_FAILURE); //We will probably have to terminate the whole program if this happens
105 close(writePipe[0]); //close end that child writes to
106 close(readPipe[1]); //close end that child reads from
108 input = fdopen(readPipe[0],"r"); output = fdopen(writePipe[1],"w");
110 setbuf(output, NULL);
117 * Writes EOF to the wrapped program and then closes all streams
118 * Kills the wrapped program if it does not exit within 1 second.
122 if (Running()) //Check if the process created is still running...
124 //fputc(EOF, output); //If it was, tell it to stop with EOF
126 TimerThread timer(2); //Wait for 2 seconds
128 while (!timer.Finished())
148 * Forces the program to pause by sending SIGSTOP
149 * Program can be resumed by calling Continue() (which sends SIGCONT)
150 * @returns true if the program could be paused, false if it couldn't (probably because it wasn't running)
152 bool Program::Pause()
154 if (pid > 0 && kill(pid,SIGSTOP) == 0)
163 * Causes a paused program to continue
164 * @returns true if the program could be continued, false if it couldn't (probably because it wasn't running)
166 bool Program::Continue()
168 if (pid > 0 && kill(pid,SIGCONT) == 0)
177 * @returns true iff the program is paused
179 bool Program::Paused() const
186 * Sends a message to the wrapped AI program
187 * WARNING: Always prints a new line after the message (so don't include a new line)
188 * This is because everything is always line buffered.
189 * @returns true if the message was successfully sent; false if it was not (ie: the process was not running!)
191 bool Program::SendMessage(const char * print, ...)
193 if (!Running()) //Is the process running...
199 if (vfprintf(output, print, ap) < 0 || fprintf(output, "\n") < 0)
214 * Retrieves a message from the wrapped AI program, waiting a maximum amount of time
215 * @param buffer - C++ string to store the resultant message in
216 * @param timeout - Maximum amount of time to wait before failure. If timeout <= 0, then GetMessage will wait indefinately.
217 * @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.
219 bool Program::GetMessage(string & buffer, double timeout)
221 if (!Running() || timeout == 0)
224 assert(&buffer != NULL);
225 GetterThread getterThread(input, buffer);
226 assert(&(getterThread.buffer) != NULL);
228 TimerThread timerThread(timeout*1000000);
230 getterThread.Start();
235 while (!getterThread.Finished())
237 if (timeout > 0 && timerThread.Finished())
251 if (buffer.size() == 1 && buffer[0] == EOF)
259 * Returns true iff the process is running
260 * @returns what I just said, fool
262 bool Program::Running() const
264 return (pid > 0 && kill(pid,0) == 0);