execnt.c

C++的一个好库。。。现在很流行

}
static FILETIME negate_FILETIME(FILETIME t)
{
    /* 2s complement negation */
    return add_64(~t.dwHighDateTime, ~t.dwLowDateTime, 0, 1);
}

/* COnvert a FILETIME to a number of seconds */
static double filetime_seconds(FILETIME t)
{
    return t.dwHighDateTime * (double)(1UL << 31) * 2 + t.dwLowDateTime * 1.0e-7;
}

static void
record_times(int pid, timing_info* time)
{
    FILETIME creation, exit, kernel, user;
    if (GetProcessTimes((HANDLE)pid, &creation, &exit, &kernel, &user))
    {
        /* Compute the elapsed time */
#if 0 /* We don't know how to get this number this on Unix */
        time->elapsed = filetime_seconds(
            add_FILETIME( exit, negate_FILETIME(creation) )
        );
#endif 

        time->system = filetime_seconds(kernel);
        time->user = filetime_seconds(user);            
    }
        
    CloseHandle((HANDLE)pid);
}
    

/*
 * execcmd() - launch an async command execution
 */

void
execcmd( 
	char *string,
	void (*func)( void *closure, int status, timing_info* ),
	void *closure,
	LIST *shell )
{
    int pid;
    int slot;
    int raw_cmd = 0 ;
    char *argv_static[ MAXARGC + 1 ];	/* +1 for NULL */
    char **argv = argv_static;
    char *p;

    /* Check to see if we need to hack around the line-length limitation. */
    /* Look for a JAMSHELL setting of "%", indicating that the command
     * should be invoked directly */
    if ( shell && !strcmp(shell->string,"%") && !list_next(shell) )
    {
        raw_cmd = 1;
        shell = 0;
    }

    if ( !is_win95_defined )
        set_is_win95();
          
    /* Find a slot in the running commands table for this one. */
    if ( is_win95 )
    {
        /* only synchronous spans are supported on Windows 95/98 */
        slot = 0;
    }
    else
    {
        for( slot = 0; slot < MAXJOBS; slot++ )
            if( !cmdtab[ slot ].pid )
                break;
    }
    if( slot == MAXJOBS )
    {
        printf( "no slots for child!\n" );
        exit( EXITBAD );
    }
  
    if( !cmdtab[ slot ].tempfile )
    {
        const char *tempdir;
        DWORD procID;

        tempdir = getTempDir();
  
        /* SVA - allocate 64 other just to be safe */
        cmdtab[ slot ].tempfile = malloc( strlen( tempdir ) + 64 );
  
        procID = GetCurrentProcessId();
  
        sprintf( cmdtab[ slot ].tempfile, "%s\\jam%d-%02d.bat", 
                 tempdir, procID, slot );		
    }

    /* Trim leading, ending white space */

    while( isspace( *string ) )
        ++string;

    /* Write to .BAT file unless the line would be too long and it
     * meets the other spawnability criteria.
     */
    if( raw_cmd && can_spawn( string ) >= MAXLINE )
    {
        if( DEBUG_EXECCMD )
            printf("Executing raw command directly\n");        
    }
    else
    {
        FILE *f;
        raw_cmd = 0;
        
        /* Write command to bat file. */
        f = fopen( cmdtab[ slot ].tempfile, "w" );
        if (!f)
        {
            printf( "failed to write command file!\n" );
            exit( EXITBAD );
        }
        fputs( string, f );
        fclose( f );

        string = cmdtab[ slot ].tempfile;
        
        if( DEBUG_EXECCMD )
        {
            if (shell)
                printf("using user-specified shell: %s", shell->string);
            else
                printf("Executing through .bat file\n");
        }
    }

    /* Forumulate argv */
    /* If shell was defined, be prepared for % and ! subs. */
    /* Otherwise, use stock /bin/sh (on unix) or cmd.exe (on NT). */

    if( shell )
    {
        int i;
        char jobno[4];
        int gotpercent = 0;

        sprintf( jobno, "%d", slot + 1 );

        for( i = 0; shell && i < MAXARGC; i++, shell = list_next( shell ) )
        {
            switch( shell->string[0] )
            {
            case '%':	argv[i] = string; gotpercent++; break;
            case '!':	argv[i] = jobno; break;
            default:	argv[i] = shell->string;
            }
            if( DEBUG_EXECCMD )
                printf( "argv[%d] = '%s'\n", i, argv[i] );
        }

        if( !gotpercent )
            argv[i++] = string;

        argv[i] = 0;
    }
    else if (raw_cmd)
    {
        argv = string_to_args(string);
    }
    else
    {
        /* don't worry, this is ignored on Win95/98, see later.. */
        argv[0] = "cmd.exe";
        argv[1] = "/Q/C";		/* anything more is non-portable */
        argv[2] = string;
        argv[3] = 0;
    }

    /* Catch interrupts whenever commands are running. */

    if( !cmdsrunning++ )
        istat = signal( SIGINT, onintr );

    /* Start the command */

    /* on Win95, we only do a synchronous call */
    if ( is_win95 )
    {
        static const char* hard_coded[] =
            {
                "del", "erase", "copy", "mkdir", "rmdir", "cls", "dir",
                "ren", "rename", "move", 0
            };
          
        const char**  keyword;
        int           len, spawn = 1;
        int           result;
        timing_info time = {0,0};
          
        for ( keyword = hard_coded; keyword[0]; keyword++ )
        {
            len = strlen( keyword[0] );
            if ( strnicmp( string, keyword[0], len ) == 0 &&
                 !isalnum(string[len]) )
            {
                /* this is one of the hard coded symbols, use 'system' to run */
                /* them.. except for "del"/"erase"                            */
                if ( keyword - hard_coded < 2 )
                    result = process_del( string );
                else
                    result = system( string );

                spawn  = 0;
                break;
            }
        }
          
        if (spawn)
        {
            char**  args;
            
            /* convert the string into an array of arguments */
            /* we need to take care of double quotes !!      */
            args = string_to_args( string );
            if ( args )
            {
#if 0
                char** arg;
                fprintf( stderr, "%s: ", args[0] );
                arg = args+1;
                while ( arg[0] )
                {
                    fprintf( stderr, " {%s}", arg[0] );
                    arg++;
                }
                fprintf( stderr, "\n" );
#endif              
                result = spawnvp( P_WAIT, args[0], args );
                record_times(result, &time);
                free_argv( args );
            }
            else
                result = 1;
        }
        func( closure, result ? EXEC_CMD_FAIL : EXEC_CMD_OK, &time );
        return;
    }

    if( DEBUG_EXECCMD )
    {
        char **argp = argv;

        printf("Executing command");
        while(*argp != 0)
        {
            printf(" [%s]", *argp);
            argp++;
        }
        printf("\n");
    }

    /* the rest is for Windows NT only */
    /* spawn doesn't like quotes around the command name */
    if ( argv[0][0] == '"')
    {
        int l = strlen(argv[0]);

        /* Clobber any closing quote, shortening the string by one
         * element */
        if (argv[0][l-1] == '"')
            argv[0][l-1] = '\0';
        
        /* Move everything *including* the original terminating zero
         * back one place in memory, covering up the opening quote */
        memmove(argv[0],argv[0]+1,l);
    }
    if( ( pid = spawnvp( P_NOWAIT, argv[0], argv ) ) == -1 )
    {
        perror( "spawn" );
        exit( EXITBAD );
    }
    /* Save the operation for execwait() to find. */

    cmdtab[ slot ].pid = pid;
    cmdtab[ slot ].func = func;
    cmdtab[ slot ].closure = closure;

    /* Wait until we're under the limit of concurrent commands. */
    /* Don't trust globs.jobs alone.                            */

    while( cmdsrunning >= MAXJOBS || cmdsrunning >= globs.jobs )
        if( !execwait() )
            break;
    
    if (argv != argv_static)
    {
        free_argv(argv);
    }
}

/*
 * execwait() - wait and drive at most one execution completion
 */

int
execwait()
{
	int i;
	int status, w;
	int rstat;
    timing_info time;

	/* Handle naive make1() which doesn't know if cmds are running. */

	if( !cmdsrunning )
	    return 0;

    if ( is_win95 )
        return 0;
          
	/* Pick up process pid and status */
    
    while( ( w = wait( &status ) ) == -1 && errno == EINTR )
        ;

	if( w == -1 )
	{
	    printf( "child process(es) lost!\n" );
	    perror("wait");
	    exit( EXITBAD );
	}

	/* Find the process in the cmdtab. */

	for( i = 0; i < MAXJOBS; i++ )
	    if( w == cmdtab[ i ].pid )
		break;

	if( i == MAXJOBS )
	{
	    printf( "waif child found!\n" );
	    exit( EXITBAD );
	}

    record_times(cmdtab[i].pid, &time);
    
	/* Clear the temp file */
    if ( cmdtab[i].tempfile )
        unlink( cmdtab[ i ].tempfile );

	/* Drive the completion */

	if( !--cmdsrunning )
	    signal( SIGINT, istat );

	if( intr )
	    rstat = EXEC_CMD_INTR;
	else if( w == -1 || status != 0 )
	    rstat = EXEC_CMD_FAIL;
	else
	    rstat = EXEC_CMD_OK;

	cmdtab[ i ].pid = 0;
	/* SVA don't leak temp files */
	if(cmdtab[i].tempfile != NULL)
	{
            free(cmdtab[i].tempfile);
            cmdtab[i].tempfile = NULL;
	}
	(*cmdtab[ i ].func)( cmdtab[ i ].closure, rstat, &time );

	return 1;
}

# if !defined( __BORLANDC__ )

/* The possible result codes from check_process_exit, below */
typedef enum { process_error, process_active, process_finished } process_state;

/* Helper for my_wait() below.  Checks to see whether the process has
 * exited and if so, records timing information.
 */
static process_state
check_process_exit(
    HANDLE process         /* The process we're looking at */
    
  , int* status            /* Storage for the finished process' exit
                            * code.  If the process is still active
                            * this location is left untouched. */
    
  , HANDLE* active_handles /* Storage for the process handle if it is
                            * found to be still active, or NULL.  The
                            * process is treated as though it is
                            * complete.  */
    
  , int* num_active        /* The current length of active_handles */
)
{
    DWORD exitcode;
    process_state result;

    /* Try to get the process exit code */
    if (!GetExitCodeProcess(process, &exitcode))
    {
        result = process_error; /* signal an error */
    }
    else if (
        exitcode == STILL_ACTIVE     /* If the process is still active */
        && active_handles != 0       /* and we've been passed a place to buffer it */
    )
    {
        active_handles[(*num_active)++] = process; /* push it onto the active stack */
        result = process_active;
    }
    else
    {
        *status = (int)((exitcode & 0xff) << 8);
        result = process_finished;
    }
    
    return result;
}

static int
my_wait( int *status )
{
	int i, num_active = 0;
	DWORD exitcode, waitcode;
	HANDLE active_handles[MAXJOBS];

	/* first see if any non-waited-for processes are dead,
	 * and return if so.
	 */
	for ( i = 0; i < globs.jobs; i++ )
    {
        int pid = cmdtab[i].pid;
        
	    if ( pid )
        {
            process_state state
                = check_process_exit((HANDLE)pid, status, active_handles, &num_active);
            
            if ( state == process_error )
                goto FAILED;
            else if ( state == process_finished )
                return pid;
	    }
	}

	/* if a child exists, wait for it to die */
	if ( !num_active )
    {
	    errno = ECHILD;
	    return -1;
	}
    
	waitcode = WaitForMultipleObjects( num_active,
                                       active_handles,
                                       FALSE,
                                       INFINITE );
	if ( waitcode != WAIT_FAILED )
    {
	    if ( waitcode >= WAIT_ABANDONED_0
             && waitcode < WAIT_ABANDONED_0 + num_active )
            i = waitcode - WAIT_ABANDONED_0;
	    else
            i = waitcode - WAIT_OBJECT_0;
        
        if ( check_process_exit(active_handles[i], status, 0, 0) == process_finished )
            return (int)active_handles[i];
	}

FAILED:
	errno = GetLastError();
	return -1;
    
}

# endif /* !__BORLANDC__ */

# endif /* USE_EXECNT */