/*
 * Copyright (c) 2000 IET Inc.
 * Copyright (c) 1994-1999 Vectaport Inc.
 *
 * Permission to use, copy, modify, distribute, and sell this software and
 * its documentation for any purpose is hereby granted without fee, provided
 * that the above copyright notice appear in all copies and that both that
 * copyright notice and this permission notice appear in supporting
 * documentation, and that the names of the copyright holders not be used in
 * advertising or publicity pertaining to distribution of the software
 * without specific, written prior permission.  The copyright holders make
 * no representations about the suitability of this software for any purpose.
 * It is provided "as is" without express or implied warranty.
 *
 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
 * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
 * IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL,
 * INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
 * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
 * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 * 
 */

/*
 * ComTerpServ is a ComTerp with added ability to load its input from a buffer.
 */

#ifndef comterpserv_h
#define comterpserv_h

/*
 * Server-oriented interpreter deals with strings
 */

#ifdef HAVE_ACE
#include <ace/config.h>
#endif

#include <ComTerp/comterp.h>

//: extended ComTerp that works with buffered IO.
class ComTerpServ : public ComTerp {
public:
    ComTerpServ(int bufsize = 1024*1024, int fd = -1);
    // construct with optional 'bufsize', and on an optional 'fd'.
    ~ComTerpServ();

    void load_string(const char*);
    // load string to be interpreted into buffer.
    void read_string(const char*);
    // load string to be interpreted into buffer, and read postfix
    // tokens from it.
    postfix_token* gen_code(const char*, int& codelen);
    // generate buffer of length 'codelen' of postfix tokens ready
    // to be converted into ComValue objects and executed.

    virtual int run(boolean one_expr=false, boolean nested=false);
    // run this interpreter until quit or exit command.
    virtual ComValue& run(const char*, boolean nested=false);
    // interpret and return value of expression.  'nested' flag used
    // to indicated nested call to the run() method, to avoid
    // re-initialization.
    virtual ComValue& run(postfix_token*, int);
    // execute a buffer of postfix tokens and return the value.
    
    virtual int runfile(const char*);
    // run interpreter on commands read from a file.

    void add_defaults();
    // add a default list of ComFunc objects to this interpreter.

    virtual boolean is_serv() { return true; } 
    // flag to test if ComTerp or ComTerpServ

protected:

    static char* s_fgets(char* s, int n, void* serv);
    // signature like fgets used to copy input from a buffer.
    static int s_feof(void* serv);
    // signature like feof used to relay end-of-file.
    static int s_ferror(void* serv);
    // signature like ferror used to relay error info.
    static int s_fputs(const char* s, void* serv);
    // signature like fputs used to copy output back to buffer.
    static char* fd_fgets(char* s, int n, void* serv);
    // signature like fgets used to explicitly read from an filedescriptor.
    static int fd_fputs(const char* s, void* serv);
    // signature like fputs used to explicitly read from an filedescriptor.

protected:
    char* _instr;
    int _inpos;
    char* _outstr;
    int _outpos;
    int _fd;
    FILE* _fptr;
    int _instat;
    int _logger_mode;

    friend class ComterpHandler;
    friend class ComTerpIOHandler;
};

#endif