path: root/src/util/strings.c

/*
     This file is part of GNUnet.
     (C) 2005, 2006 Christian Grothoff (and other contributing authors)

     GNUnet 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 2, or (at your
     option) any later version.

     GNUnet 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 GNUnet; see the file COPYING.  If not, write to the
     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
     Boston, MA 02111-1307, USA.
*/

/**
 * @file util/strings.c
 * @brief string functions
 * @author Nils Durner
 * @author Christian Grothoff
 */

#include "platform.h"
#if HAVE_ICONV
#include <iconv.h>
#endif
#include "gnunet_common.h"
#include "gnunet_strings_lib.h"

#define LOG(kind,...) GNUNET_log_from (kind, "util", __VA_ARGS__)

#define LOG_STRERROR(kind,syscall) GNUNET_log_from_strerror (kind, "util", syscall)


/**
 * Fill a buffer of the given size with
 * count 0-terminated strings (given as varargs).
 * If "buffer" is NULL, only compute the amount of
 * space required (sum of "strlen(arg)+1").
 *
 * Unlike using "snprintf" with "%s", this function
 * will add 0-terminators after each string.  The
 * "GNUNET_string_buffer_tokenize" function can be
 * used to parse the buffer back into individual
 * strings.
 *
 * @param buffer the buffer to fill with strings, can
 *               be NULL in which case only the necessary
 *               amount of space will be calculated
 * @param size number of bytes available in buffer
 * @param count number of strings that follow
 * @param ... count 0-terminated strings to copy to buffer
 * @return number of bytes written to the buffer
 *         (or number of bytes that would have been written)
 */
size_t
GNUNET_STRINGS_buffer_fill (char *buffer, size_t size, unsigned int count, ...)
{
  size_t needed;
  size_t slen;
  const char *s;
  va_list ap;

  needed = 0;
  va_start (ap, count);
  while (count > 0)
  {
    s = va_arg (ap, const char *);

    slen = strlen (s) + 1;
    if (buffer != NULL)
    {
      GNUNET_assert (needed + slen <= size);
      memcpy (&buffer[needed], s, slen);
    }
    needed += slen;
    count--;
  }
  va_end (ap);
  return needed;
}


/**
 * Given a buffer of a given size, find "count"
 * 0-terminated strings in the buffer and assign
 * the count (varargs) of type "const char**" to the
 * locations of the respective strings in the
 * buffer.
 *
 * @param buffer the buffer to parse
 * @param size size of the buffer
 * @param count number of strings to locate
 * @return offset of the character after the last 0-termination
 *         in the buffer, or 0 on error.
 */
unsigned int
GNUNET_STRINGS_buffer_tokenize (const char *buffer, size_t size,
                                unsigned int count, ...)
{
  unsigned int start;
  unsigned int needed;
  const char **r;
  va_list ap;

  needed = 0;
  va_start (ap, count);
  while (count > 0)
  {
    r = va_arg (ap, const char **);

    start = needed;
    while ((needed < size) && (buffer[needed] != '\0'))
      needed++;
    if (needed == size)
    {
      va_end (ap);
      return 0;                 /* error */
    }
    *r = &buffer[start];
    needed++;                   /* skip 0-termination */
    count--;
  }
  va_end (ap);
  return needed;
}


/**
 * Convert a given filesize into a fancy human-readable format.
 *
 * @param size number of bytes
 * @return fancy representation of the size (possibly rounded) for humans
 */
char *
GNUNET_STRINGS_byte_size_fancy (unsigned long long size)
{
  const char *unit = _( /* size unit */ "b");
  char *ret;

  if (size > 5 * 1024)
  {
    size = size / 1024;
    unit = "KiB";
    if (size > 5 * 1024)
    {
      size = size / 1024;
      unit = "MiB";
      if (size > 5 * 1024)
      {
        size = size / 1024;
        unit = "GiB";
        if (size > 5 * 1024)
        {
          size = size / 1024;
          unit = "TiB";
        }
      }
    }
  }
  ret = GNUNET_malloc (32);
  GNUNET_snprintf (ret, 32, "%llu %s", size, unit);
  return ret;
}


/**
 * Convert a given fancy human-readable size to bytes.
 *
 * @param fancy_size human readable string (i.e. 1 MB)