/* glpenv03.c (terminal output) */

 /***********************************************************************

 *  This code is part of GLPK (GNU Linear Programming Kit).

 *

 *  Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008,

 *  2009, 2010 Andrew Makhorin, Department for Applied Informatics,

 *  Moscow Aviation Institute, Moscow, Russia. All rights reserved.

 *  E-mail: <mao@gnu.org>.

 *

 *  GLPK is free software: you can redistribute it and/or modify it

 *  under the terms of the GNU General Public License as published by

 *  the Free Software Foundation, either version 3 of the License, or

 *  (at your option) any later version.

 *

 *  GLPK is distributed in the hope that it will be useful, but WITHOUT

 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY

 *  or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public

 *  License for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with GLPK. If not, see <http://www.gnu.org/licenses/>.

 ***********************************************************************/

 #include "glpapi.h"

 /***********************************************************************

 *  NAME

 *

 *  glp_printf - write formatted output to terminal

 *

 *  SYNOPSIS

 *

 *  void glp_printf(const char *fmt, ...);

 *

 *  DESCRIPTION

 *

 *  The routine glp_printf uses the format control string fmt to format

 *  its parameters and writes the formatted output to the terminal. */

 void glp_printf(const char *fmt, ...)

 {     va_list arg;

       va_start(arg, fmt);

       xvprintf(fmt, arg);

       va_end(arg);

       return;

 }

 /***********************************************************************

 *  NAME

 *

 *  glp_vprintf - write formatted output to terminal

 *

 *  SYNOPSIS

 *

 *  void glp_vprintf(const char *fmt, va_list arg);

 *

 *  DESCRIPTION

 *

 *  The routine glp_vprintf uses the format control string fmt to format

 *  its parameters specified by the list arg and writes the formatted

 *  output to the terminal. */

 void glp_vprintf(const char *fmt, va_list arg)

 {     ENV *env = get_env_ptr();

       /* if terminal output is disabled, do nothing */

       if (!env->term_out) goto skip;

       /* format the output */

       vsprintf(env->term_buf, fmt, arg);

       /* pass the output to the user-defined routine */

       if (env->term_hook != NULL)

       {  if (env->term_hook(env->term_info, env->term_buf) != 0)

             goto skip;

       }

       /* send the output to the terminal */

       fputs(env->term_buf, stdout);

       fflush(stdout);

       /* copy the output to the text file */

       if (env->tee_file != NULL)

       {  fputs(env->term_buf, env->tee_file);

          fflush(env->tee_file);

       }

 skip: return;

 }

 /***********************************************************************

 *  NAME

 *

 *  glp_term_out - enable/disable terminal output

 *

 *  SYNOPSIS

 *

 *  int glp_term_out(int flag);

 *

 *  DESCRIPTION

 *

 *  Depending on the parameter flag the routine glp_term_out enables or

 *  disables terminal output performed by glpk routines:

 *

 *  GLP_ON  - enable terminal output;

 *  GLP_OFF - disable terminal output.

 *

 *  RETURNS

 *

 *  The routine glp_term_out returns the previous value of the terminal

 *  output flag. */

 int glp_term_out(int flag)

 {     ENV *env = get_env_ptr();

       int old = env->term_out;

       if (!(flag == GLP_ON || flag == GLP_OFF))

          xerror("glp_term_out: flag = %d; invalid value\n", flag);

       env->term_out = flag;

       return old;

 }

 /***********************************************************************

 *  NAME

 *

 *  glp_term_hook - install hook to intercept terminal output

 *

 *  SYNOPSIS

 *

 *  void glp_term_hook(int (*func)(void *info, const char *s),

 *     void *info);

 *

 *  DESCRIPTION

 *

 *  The routine glp_term_hook installs a user-defined hook routine to

 *  intercept all terminal output performed by glpk routines.

 *

 *  This feature can be used to redirect the terminal output to other

 *  destination, for example to a file or a text window.

 *

 *  The parameter func specifies the user-defined hook routine. It is

 *  called from an internal printing routine, which passes to it two

 *  parameters: info and s. The parameter info is a transit pointer,

 *  specified in the corresponding call to the routine glp_term_hook;

 *  it may be used to pass some information to the hook routine. The

 *  parameter s is a pointer to the null terminated character string,

 *  which is intended to be written to the terminal. If the hook routine

 *  returns zero, the printing routine writes the string s to the

 *  terminal in a usual way; otherwise, if the hook routine returns

 *  non-zero, no terminal output is performed.

 *

 *  To uninstall the hook routine the parameters func and info should be

 *  specified as NULL. */

 void glp_term_hook(int (*func)(void *info, const char *s), void *info)

 {     ENV *env = get_env_ptr();

       if (func == NULL)

       {  env->term_hook = NULL;

          env->term_info = NULL;

       }

       else

       {  env->term_hook = func;

          env->term_info = info;

       }

       return;

 }

 /***********************************************************************

 *  NAME

 *

 *  glp_open_tee - start copying terminal output to text file

 *

 *  SYNOPSIS

 *

 *  int glp_open_tee(const char *fname);

 *

 *  DESCRIPTION

 *

 *  The routine glp_open_tee starts copying all the terminal output to

 *  an output text file, whose name is specified by the character string

 *  fname.

 *

 *  RETURNS

 *

 *  0 - operation successful

 *  1 - copying terminal output is already active

 *  2 - unable to create output file */

 int glp_open_tee(const char *fname)

 {     ENV *env = get_env_ptr();

       if (env->tee_file != NULL)

       {  /* copying terminal output is already active */

          return 1;

       }

       env->tee_file = fopen(fname, "w");

       if (env->tee_file == NULL)

       {  /* unable to create output file */

          return 2;

       }

       return 0;

 }

 /***********************************************************************

 *  NAME

 *

 *  glp_close_tee - stop copying terminal output to text file

 *

 *  SYNOPSIS

 *

 *  int glp_close_tee(void);

 *

 *  DESCRIPTION

 *

 *  The routine glp_close_tee stops copying the terminal output to the

 *  output text file previously open by the routine glp_open_tee closing

 *  that file.

 *

 *  RETURNS

 *

 *  0 - operation successful

 *  1 - copying terminal output was not started */

 int glp_close_tee(void)

 {     ENV *env = get_env_ptr();

       if (env->tee_file == NULL)

       {  /* copying terminal output was not started */

          return 1;

       }

       fclose(env->tee_file);

       env->tee_file = NULL;

       return 0;

 }

 /* eof */