libs3-1.4/inc/string_buffer.h

   1 /** **************************************************************************
   2  * string_buffer.h
   3  *
   4  * Copyright 2008 Bryan Ischo <bryan@ischo.com>
   5  *
   6  * This file is part of libs3.
   7  *
   8  * libs3 is free software: you can redistribute it and/or modify it under the
   9  * terms of the GNU General Public License as published by the Free Software
  10  * Foundation, version 3 of the License.
  11  *
  12  * In addition, as a special exception, the copyright holders give
  13  * permission to link the code of this library and its programs with the
  14  * OpenSSL library, and distribute linked combinations including the two.
  15  *
  16  * libs3 is distributed in the hope that it will be useful, but WITHOUT ANY
  17  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  18  * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
  19  * details.
  20  *
  21  * You should have received a copy of the GNU General Public License version 3
  22  * along with libs3, in a file named COPYING.  If not, see
  23  * <http://www.gnu.org/licenses/>.
  24  *
  25  ************************************************************************** **/
  26
  27 #ifndef STRING_BUFFER_H
  28 #define STRING_BUFFER_H
  29
  30 #include <stdio.h>
  31
  32
  33 // Declare a string_buffer with the given name of the given maximum length
  34 #define string_buffer(name, len)                                        \
  35     char name[len + 1];                                                 \
  36     int name##Len
  37
  38
  39 // Initialize a string_buffer
  40 #define string_buffer_initialize(sb)                                    \
  41     do {                                                                \
  42         sb[0] = 0;                                                      \
  43         sb##Len = 0;                                                    \
  44     } while (0)
  45
  46
  47 // Append [len] bytes of [str] to [sb], setting [all_fit] to 1 if it fit, and
  48 // 0 if it did not
  49 #define string_buffer_append(sb, str, len, all_fit)                     \
  50     do {                                                                \
  51         sb##Len += snprintf(&(sb[sb##Len]), sizeof(sb) - sb##Len - 1,   \
  52                             "%.*s", (int) (len), str);                  \
  53         if (sb##Len > (int) (sizeof(sb) - 1)) {                         \
  54             sb##Len = sizeof(sb) - 1;                                   \
  55             all_fit = 0;                                                \
  56         }                                                               \
  57         else {                                                          \
  58             all_fit = 1;                                                \
  59         }                                                               \
  60     } while (0)
  61
  62
  63 // Declare a string multibuffer with the given name of the given maximum size
  64 #define string_multibuffer(name, size)                                  \
  65     char name[size];                                                    \
  66     int name##Size
  67
  68
  69 // Initialize a string_multibuffer
  70 #define string_multibuffer_initialize(smb)                              \
  71     do {                                                                \
  72         smb##Size = 0;                                                  \
  73     } while (0)
  74
  75
  76 // Evaluates to the current string within the string_multibuffer
  77 #define string_multibuffer_current(smb)                                  \
  78     &(smb[smb##Size])
  79
  80
  81 // Adds a new string to the string_multibuffer
  82 #define string_multibuffer_add(smb, str, len, all_fit)                  \
  83     do {                                                                \
  84         smb##Size += (snprintf(&(smb[smb##Size]),                       \
  85                                sizeof(smb) - smb##Size,                 \
  86                                "%.*s", (int) (len), str) + 1);          \
  87         if (smb##Size > (int) sizeof(smb)) {                            \
  88             smb##Size = sizeof(smb);                                    \
  89             all_fit = 0;                                                \
  90         }                                                               \
  91         else {                                                          \
  92             all_fit = 1;                                                \
  93         }                                                               \
  94     } while (0)
  95
  96
  97 // Appends to the current string in the string_multibuffer.  There must be a
  98 // current string, meaning that string_multibuffer_add must have been called
  99 // at least once for this string_multibuffer.
 100 #define string_multibuffer_append(smb, str, len, all_fit)               \
 101     do {                                                                \
 102         smb##Size--;                                                    \
 103         string_multibuffer_add(smb, str, len, all_fit);                 \
 104     } while (0)
 105
 106
 107 #endif /* STRING_BUFFER_H */