/* 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 */