streambuf.cpp revision 0b70d74ee05462446d178279177702296709eb9e 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *  * Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 *  * Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in
12 *    the documentation and/or other materials provided with the
13 *    distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <streambuf>
30#include <algorithm>  // for min
31namespace std {
32
33// Implementation of the streambuf, common stuff for all the stream buffers.
34streambuf::streambuf()
35    : mPutBeg(0), mPutCurr(0), mPutEnd(0) { }
36
37streambuf::streambuf(const streambuf& sb)
38    : mPutBeg(sb.mPutBeg), mPutCurr(sb.mPutCurr), mPutEnd(sb.mPutEnd) { }
39
40streambuf::~streambuf() {}
41
42streamsize streambuf::xsputn(const char_type* str, streamsize num) {
43    streamsize written = 0;
44
45    while (written < num) {
46        const streamsize avail = this->epptr() - this->pptr();
47        if (avail) {
48            const streamsize remaining = num - written;
49            const streamsize len = std::min(avail, remaining);
50            traits_type::copy(this->pptr(), str, len);
51            written += len;
52            str += len;
53            this->pbump(len);
54        }
55
56        if (written < num) {
57            // Indicate to the impl that we overflown. Either the impl
58            // can increase its buffer and consume one character (in
59            // which case eof() is not returned) or it can't and we
60            // stop here.
61            int_type c = this->overflow(traits_type::to_int_type(*str));
62            if (!traits_type::eq_int_type(c, traits_type::eof())) {
63                ++written;
64                ++str;
65            } else {
66                break;
67            }
68        }
69    }
70    return written;
71}
72
73}  // namespace std
74