/**************************************************************\

  drsdaq

  Main program for data acquisition, starts threads for console input.
  
  Original program by S. Commichau.
  
  Oliver Grimm, May 2010
 
\**************************************************************/

#define LOCKFILE "/tmp/CT3_DAQ_LOCK"

#include <stdio.h>
#include <signal.h>
#include <readline/readline.h>
#include <readline/history.h>

#include "DAQReadout.h"

// Function prototypes
void CrashHandler(int);
void ExitFunction();

// ================
//   Main program
// ================
//
// Several unlikely system call failures are handled via throwing an exception.

int main() {

  char str[MAX_COM_SIZE], *Command;
  int LockDescriptor;

  // Assure only one instance of program runs (lock creator written to log file)
  // Lock file deleted by destructor
  if((LockDescriptor = open(LOCKFILE,O_WRONLY|O_CREAT|O_EXCL, S_IWUSR|S_IRUSR|S_IRGRP|S_IROTH)) == -1) {
    if(errno==EEXIST) {
      printf("Error: Lock file already existing\n");
      snprintf(str, sizeof(str), "paste %s -s -d ' '",LOCKFILE);
      system(str);
    }
    else printf("Could not create lock file %s (%s)\n", LOCKFILE, strerror(errno));
    exit(EXIT_FAILURE);
  }
  close(LockDescriptor);
  sprintf(str,"echo Created >%s; date >>%s; echo by $USER@$HOSTNAME >>%s",LOCKFILE,LOCKFILE,LOCKFILE);
  system(str);

  // Readline library uses getc() (allows interruption by signal)
  rl_getc_function = getc;

  // writev() in DAQ thread needs to be able to write at least 3 chunks
  if(IOV_MAX < 2) {
	printf("Fatal error: IOV_MAX is less than 2, cannot use writev() to write event data.\n");
	exit(EXIT_FAILURE);
  }
     
  system("clear");
  printf("\n*** DRS readout (built %s, %s, revision %s) *** \n\n",__DATE__, __TIME__, REVISION);

  // Set exit function
  atexit(&ExitFunction);

  // Construct main instance (static ensures destructor is called with exit())
  static DAQReadout M;

  // Set signal handlers
  signal(SIGILL, &CrashHandler);
  signal(SIGABRT, &CrashHandler);
  signal(SIGFPE, &CrashHandler);
  signal(SIGSEGV, &CrashHandler);
  signal(SIGBUS, &CrashHandler);

  // Command loop
  while (!M.ExitRequest) {
    // Assemble prompt
    if (M.NumBoards == 0) snprintf(M.Prompt,sizeof(M.Prompt),"\rDAQ> "); 
    else if (M.FirstBoard == M.LastBoard) snprintf(M.Prompt,sizeof(M.Prompt),"\rDAQ|B%d> ",M.FirstBoard); 
    else snprintf(M.Prompt,sizeof(M.Prompt),"\rDAQ|B%d-%d> ",M.FirstBoard,M.LastBoard); 

    // Read Command
    Command = readline(M.Prompt);
    if (Command == NULL) continue;
    if(strlen(Command)>0) add_history(Command);

    // Process command
	DimClient::sendCommand(SERVER_NAME"/Command", Command);
    free(Command);
  }
}


// Remove lock file before running default signal code
void CrashHandler(int Signal) {

  remove(LOCKFILE);
  printf("Caught signal number %d. Removed lockfile and performing standard signal action. Good luck.\n",Signal);
  signal(Signal, SIG_DFL);
  raise(Signal);
}

// This function will be implicitly called by exit()
void ExitFunction() {

  if (remove(LOCKFILE) == -1) {
    printf("Could not remove lock file %s (%s)\n", LOCKFILE, strerror(errno));
  }
}