release/src/router/libjson-c/printbuf.h

   1 /*
   2  * $Id: printbuf.h,v 1.4 2006/01/26 02:16:28 mclark Exp $
   3  *
   4  * Copyright (c) 2004, 2005 Metaparadigm Pte. Ltd.
   5  * Michael Clark <michael@metaparadigm.com>
   6  *
   7  * This library is free software; you can redistribute it and/or modify
   8  * it under the terms of the MIT license. See COPYING for details.
   9  *
  10  *
  11  * Copyright (c) 2008-2009 Yahoo! Inc.  All rights reserved.
  12  * The copyrights to the contents of this file are licensed under the MIT License
  13  * (http://www.opensource.org/licenses/mit-license.php)
  14  */
  15
  16 #ifndef _printbuf_h_
  17 #define _printbuf_h_
  18
  19 #ifdef __cplusplus
  20 extern "C" {
  21 #endif
  22
  23 struct printbuf {
  24   char *buf;
  25   int bpos;
  26   int size;
  27 };
  28
  29 extern struct printbuf*
  30 printbuf_new(void);
  31
  32 /* As an optimization, printbuf_memappend_fast is defined as a macro
  33  * that handles copying data if the buffer is large enough; otherwise
  34  * it invokes printbuf_memappend_real() which performs the heavy
  35  * lifting of realloc()ing the buffer and copying data.
  36  * Your code should not use printbuf_memappend directly--use
  37  * printbuf_memappend_fast instead.
  38  */
  39 extern int
  40 printbuf_memappend(struct printbuf *p, const char *buf, int size);
  41
  42 #define printbuf_memappend_fast(p, bufptr, bufsize)          \
  43 do {                                                         \
  44   if ((p->size - p->bpos) > bufsize) {                       \
  45     memcpy(p->buf + p->bpos, (bufptr), bufsize);             \
  46     p->bpos += bufsize;                                      \
  47     p->buf[p->bpos]= '\0';                                   \
  48   } else {  printbuf_memappend(p, (bufptr), bufsize); }      \
  49 } while (0)
  50
  51 #define printbuf_length(p) ((p)->bpos)
  52
  53 /**
  54  * Set len bytes of the buffer to charvalue, starting at offset offset.
  55  * Similar to calling memset(x, charvalue, len);
  56  *
  57  * The memory allocated for the buffer is extended as necessary.
  58  *
  59  * If offset is -1, this starts at the end of the current data in the buffer.
  60  */
  61 extern int
  62 printbuf_memset(struct printbuf *pb, int offset, int charvalue, int len);
  63
  64 extern int
  65 sprintbuf(struct printbuf *p, const char *msg, ...);
  66
  67 extern void
  68 printbuf_reset(struct printbuf *p);
  69
  70 extern void
  71 printbuf_free(struct printbuf *p);
  72
  73 #ifdef __cplusplus
  74 }
  75 #endif
  76
  77 #endif