log_init.c

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/*!
 * \file   log/lib/src/log_init.c
 * \brief  Initialize the LOG_tag
 *
 * \date   02/13/2003
 * \author Jork Loeser <jork.loeser@inf.tu-dresden.de>
 *
 */
/* (c) 2003 Technische Universitaet Dresden
 * This file is part of DROPS, which is distributed under the terms of the
 * GNU General Public License 2. Please see the COPYING file for details.
 */

#include <l4/log/l4log.h>
#include <l4/crtx/ctor.h>
#include <l4/util/mbi_argv.h>
char LOG_tag[9] __attribute__((weak));
char LOG_tag[9] = "";

/* Initialize the LOG_tag after the cmdline has been parsed, but before
 * the l4env or other systems come up.
 */
L4C_CTOR(LOG_setup_tag, L4CTOR_BEFORE_BACKEND);

/*!\brief Set the LOG tag.
 *
 * This function should be called by the startup-code, prior to any output
 * of the loglib (if used) or the thread-creation using the thread package.
 * If l4util_progname is empty, it will be filled with the first 8 chars of
 * the last portion of the program name.
 *
 * With L4Env, this function is called after initializing l4util's argc/argv.
 * It is called via constructors a second time before calling main().
 * Without L4Env and the __main() from l4util, this function is called
 * as constructor after initializing argc/argv.
 */
void LOG_setup_tag(void)
{
  const char *name = l4util_argv[0];

  if (!name)
    return;

  if (LOG_tag[0] == 0)
    {
      char *d;
      const char *e;

      /* look for last '/' in name */
      for (e = name; *e; e++)
        if (*e == '/')
          name = e + 1;

      e = LOG_tag + sizeof(LOG_tag) - 1;
      for (d = LOG_tag; *name && d < e; )
        *d++ = *name++;
      *d = 0;
    }
}