unix/SysLocalAPIManager.cpp

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/* Copyright (c) 2005-2009 Rexx Language Association. All rights reserved.    */
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#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
 
#include "SysLocalAPIManager.hpp"
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/stat.h>
 
 
void SysLocalAPIManager::startServerProcess()
{
    char apiExeName[] = "rxapi";
    char *apiExeArg[2];
    apiExeArg[0] = apiExeName;
    apiExeArg[1] = NULL;
 
    if (signal(SIGPIPE, SIG_IGN) == SIG_ERR) {
        return;
    }
 
    pid_t pid = fork();
    if (pid < 0) {
        throw new ServiceException(API_FAILURE, "Unable to start API server");
    }
    if (pid != 0) {
        // we are the parent process
        return;
    }
    // if we get here we are the child process
 
    // become the session leader
    setsid();
 
    // housekeeping - chdir to the root subdir and close all open files
    int ignore = chdir("/");
    umask(0);
    for(int i = 0; i < 1024; i++) {
        close(i);
    }
 
    // now start rxapi
    if (execvp(apiExeName, apiExeArg) == -1) {
        throw new ServiceException(API_FAILURE, "Unable to start API server");
    }
 
    return;
}
 
 
/**
 * Check to see if we've inherited a session queue from a calling process.  This shows
 * up as an environment variable value.
 *
 * @param sessionQueue
 *               The returned session queue handle, if it exists.
 *
 * @return true if the session queue is inherited, false if a new once needs to be created.
 */
bool SysLocalAPIManager::getActiveSessionQueue(QueueHandle &sessionQueue)
{
    // check to see if we have an env variable set...if we do we
    // inherit from our parent session
    char *envbuffer = getenv("RXQUEUESESSION");
    if (envbuffer != NULL)
    {
        sscanf(envbuffer, "%p", (char **)&sessionQueue);
        return true;
    }
    return false;
}
 
/**
 * Set the active session queue as an environment variable.
 *
 * @param sessionQueue
 *               The session queue handle.
 */
void SysLocalAPIManager::setActiveSessionQueue(QueueHandle sessionQueue)
{
    char envbuffer[MAX_QUEUE_NAME_LENGTH+1];
    // set this as an environment variable for programs we call
    snprintf(envbuffer, sizeof envbuffer, "%p", (void *)sessionQueue);
    setenv("RXQUEUESESSION", envbuffer, 1); // overwrite the old value
}