release/src/router/udpxy/prbuf.h

   1 /* @(#) interface to memory-buffer printf API
   2  *
   3  * Copyright 2008-2011 Pavel V. Cherenkov (pcherenkov@gmail.com)
   4  *
   5  *  This file is part of udpxy.
   6  *
   7  *  udpxy is free software: you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation, either version 3 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  udpxy is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *  GNU General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License
  18  *  along with udpxy.  If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #ifndef PRBUF_H_12272007bsl_
  22 #define PRBUF_H_12272007bsl_
  23
  24 typedef struct printbuf* prbuf_t;
  25
  26 #ifdef __cplusplus
  27     extern "C" {
  28 #endif
  29
  30
  31 /* create/open print buffer
  32  *
  33  * @param pb    - address of the new print buffer
  34  * @param buf   - (pre-allocated) memory buffer
  35  *                to associate new printbuffer with
  36  * @param n     - size (in bytes) of the memory buffer
  37  *
  38  * @return 0 if success: contents of pb are updated with
  39  *         the address on new printbuffer; -1 otherwise
  40  */
  41 int prbuf_open( prbuf_t* pb, void* buf, size_t n );
  42
  43
  44 /* close print buffer
  45  *
  46  * @param pb    - print buffer to close
  47  *
  48  * @return 0 if success, -1 otherwise
  49  */
  50 int prbuf_close( prbuf_t pb );
  51
  52
  53 /* write a formatted string into the print buffer,
  54  * beginning at the current position (each write
  55  * advances the position appropriately)
  56  *
  57  * @param   - destination print buffer
  58  * @param   - printf-style format string
  59  *
  60  * @return 0 if end of buffer has been reached,
  61  *         -1 in case of error,
  62  *         n > 0, where n is the number of characters written
  63  *         into the buffer (not including trailing zero character)
  64  */
  65 int prbuf_printf( prbuf_t pb, const char* format, ... );
  66
  67
  68 /* @ return length of the text inside the buffer
  69  *   NOT including the termination zero character
  70  *
  71  */
  72 size_t prbuf_len( prbuf_t pb );
  73
  74
  75 /* set current position to the beginning of the print buffer
  76  *
  77  * @param pb    - destination print buffer
  78  */
  79 void prbuf_rewind( prbuf_t pb );
  80
  81 #ifdef __cplusplus
  82 }
  83 #endif
  84
  85 #endif /* PRBUF_H_12272007bsl_ */
  86
  87 /* __EOF__ */
  88