osdProcess.c File Reference

#include <string.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <unistd.h>
#include <sched.h>
#include <sys/types.h>
#include <pwd.h>
#include "osiProcess.h"
#include "errlog.h"
#include "epicsAssert.h"

Include dependency graph for osdProcess.c:

Go to the source code of this file.

Functions
LIBCOM_API osiGetUserNameReturn epicsStdCall	osiGetUserName (char *pBuf, unsigned bufSizeIn)
LIBCOM_API osiSpawnDetachedProcessReturn epicsStdCall	osiSpawnDetachedProcess (const char *pProcessName, const char *pBaseExecutableName)

Function Documentation

LIBCOM_API osiGetUserNameReturn epicsStdCall osiGetUserName	(	char *	pBuf,
		unsigned	bufSizeIn
	)

Definition at line 33 of file osdProcess.c.

{
    struct passwd *p;

    p = getpwuid ( getuid () );
    if ( p && p->pw_name ) {
        size_t len = strlen ( p->pw_name );
        unsigned uiLength;

        if ( len > UINT_MAX || len <= 0 ) {
            return osiGetUserNameFail;
        }
        uiLength = (unsigned) len;

        if ( uiLength + 1 >= bufSizeIn ) {
            return osiGetUserNameFail;
        }

        strncpy ( pBuf, p->pw_name, (size_t) bufSizeIn );

        return osiGetUserNameSuccess;
    }
    else {
        return osiGetUserNameFail;
    }
}

LIBCOM_API osiSpawnDetachedProcessReturn epicsStdCall osiSpawnDetachedProcess	(	const char *	pProcessName,
		const char *	pBaseExecutableName
	)

Definition at line 61 of file osdProcess.c.

{
    int status;

    /*
     * create a duplicate process
     */
    status = fork ();
    if (status < 0) {
        return osiSpawnDetachedProcessFail;
    }

    /*
     * return to the caller
     * in the initiating (parent) process
     */
    if (status) {
        return osiSpawnDetachedProcessSuccess;
    }

    /*
     * This is executed only by the new child process.
     * Close all open files except for STDIO, so they will not
     * be inherited by the new program.
     */
    {
        int fd, maxfd = sysconf ( _SC_OPEN_MAX );
        for ( fd = 0; fd <= maxfd; fd++ ) {
            if (fd==STDIN_FILENO) continue;
            if (fd==STDOUT_FILENO) continue;
            if (fd==STDERR_FILENO) continue;
            close (fd);
        }
    }

#if defined(_POSIX_THREAD_PRIORITY_SCHEDULING) && _POSIX_THREAD_PRIORITY_SCHEDULING > 0
    /*
     * Drop real-time SCHED_FIFO priority
     */
    {
        struct sched_param p;

        p.sched_priority = 0;
        status = sched_setscheduler(0, SCHED_OTHER, &p);
    }
#endif /* _POSIX_THREAD_PRIORITY_SCHEDULING */

    /*
     * Run the specified executable
     */
    status = execlp (pBaseExecutableName, pBaseExecutableName, (char *)NULL);
    if ( status < 0 ) {
        fprintf ( stderr, "**** The executable \"%s\" couldn't be located\n", pBaseExecutableName );
        fprintf ( stderr, "**** because of errno = \"%s\".\n", strerror (errno) );
        fprintf ( stderr, "**** You may need to modify your PATH environment variable.\n" );
        fprintf ( stderr, "**** Unable to start \"%s\" process.\n", pProcessName);
    }
    /* Don't run our parent's atexit() handlers */
    _exit ( -1 );
}