1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16#ifndef _ADB_UTILS_H
17#define _ADB_UTILS_H
18
19/* bounded buffer functions */
20
21/* all these functions are used to append data to a bounded buffer.
22 *
23 * after each operation, the buffer is guaranteed to be zero-terminated,
24 * even in the case of an overflow. they all return the new buffer position
25 * which allows one to use them in succession, only checking for overflows
26 * at the end. For example:
27 *
28 *    BUFF_DECL(temp,p,end,1024);
29 *    char*    p;
30 *
31 *    p = buff_addc(temp, end, '"');
32 *    p = buff_adds(temp, end, string);
33 *    p = buff_addc(temp, end, '"');
34 *
35 *    if (p >= end) {
36 *        overflow detected. note that 'temp' is
37 *        zero-terminated for safety.
38 *    }
39 *    return strdup(temp);
40 */
41
42/* tries to add a character to the buffer, in case of overflow
43 * this will only write a terminating zero and return buffEnd.
44 */
45char*   buff_addc (char*  buff, char*  buffEnd, int  c);
46
47/* tries to add a string to the buffer */
48char*   buff_adds (char*  buff, char*  buffEnd, const char*  s);
49
50/* tries to add a bytes to the buffer. the input can contain zero bytes,
51 * but a terminating zero will always be appended at the end anyway
52 */
53char*   buff_addb (char*  buff, char*  buffEnd, const void*  data, int  len);
54
55/* tries to add a formatted string to a bounded buffer */
56char*   buff_add  (char*  buff, char*  buffEnd, const char*  format, ... );
57
58/* convenience macro used to define a bounded buffer, as well as
59 * a 'cursor' and 'end' variables all in one go.
60 *
61 * note: this doesn't place an initial terminating zero in the buffer,
62 * you need to use one of the buff_ functions for this. or simply
63 * do _cursor[0] = 0 manually.
64 */
65#define  BUFF_DECL(_buff,_cursor,_end,_size)   \
66    char   _buff[_size], *_cursor=_buff, *_end = _cursor + (_size)
67
68#endif /* _ADB_UTILS_H */
69