aboutsummaryrefslogtreecommitdiffstats
path: root/libqpdf/FileInputSource.cc
blob: 4e4a34bff97ac560b749ee6412a10f29ee6ad4df (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
#include <qpdf/FileInputSource.hh>
#include <string.h>
#include <qpdf/QUtil.hh>
#include <qpdf/QPDFExc.hh>
#include <algorithm>

FileInputSource::FileInputSource() :
    close_file(false),
    file(0)
{
}

void
FileInputSource::setFilename(char const* filename)
{
    destroy();
    this->filename = filename;
    this->close_file = true;
    this->file = QUtil::safe_fopen(this->filename.c_str(), "rb");
}

void
FileInputSource::setFile(
    char const* description, FILE* filep, bool close_file)
{
    destroy();
    this->filename = description;
    this->close_file = close_file;
    this->file = filep;
    this->seek(0, SEEK_SET);
}

FileInputSource::~FileInputSource()
{
    destroy();
}

void
FileInputSource::destroy()
{
    if (this->file && this->close_file)
    {
	fclose(this->file);
	this->file = 0;
    }
}

qpdf_offset_t
FileInputSource::findAndSkipNextEOL()
{
    qpdf_offset_t result = 0;
    bool done = false;
    char buf[10240];
    while (! done)
    {
        qpdf_offset_t cur_offset = QUtil::tell(this->file);
        size_t len = this->read(buf, sizeof(buf));
        if (len == 0)
        {
            done = true;
            result = this->tell();
        }
        else
        {
            char* p1 = static_cast<char*>(memchr(buf, '\r', len));
            char* p2 = static_cast<char*>(memchr(buf, '\n', len));
            char* p = (p1 && p2) ? std::min(p1, p2) : p1 ? p1 : p2;
            if (p)
            {
                result = cur_offset + (p - buf);
                // We found \r or \n.  Keep reading until we get past
                // \r and \n characters.
                this->seek(result + 1, SEEK_SET);
                char ch;
                while (! done)
                {
                    if (this->read(&ch, 1) == 0)
                    {
                        done = true;
                    }
                    else if (! ((ch == '\r') || (ch == '\n')))
                    {
                        this->unreadCh(ch);
                        done = true;
                    }
                }
            }
        }
    }
    return result;
}

std::string const&
FileInputSource::getName() const
{
    return this->filename;
}

qpdf_offset_t
FileInputSource::tell()
{
    return QUtil::tell(this->file);
}

void
FileInputSource::seek(qpdf_offset_t offset, int whence)
{
    QUtil::os_wrapper(std::string("seek to ") + this->filename + ", offset " +
		      QUtil::int_to_string(offset) + " (" +
		      QUtil::int_to_string(whence) + ")",
		      QUtil::seek(this->file, offset, whence));
}

void
FileInputSource::rewind()
{
    ::rewind(this->file);
}

size_t
FileInputSource::read(char* buffer, size_t length)
{
    this->last_offset = this->tell();
    size_t len = fread(buffer, 1, length, this->file);
    if (len == 0)
    {
        if (ferror(this->file))
        {
            throw QPDFExc(qpdf_e_system,
                          this->filename, "",
                          this->last_offset,
                          std::string("read ") +
                          QUtil::int_to_string(length) + " bytes");
        }
        else if (length > 0)
        {
            this->seek(0, SEEK_END);
            this->last_offset = this->tell();
        }
    }
    return len;
}

void
FileInputSource::unreadCh(char ch)
{
    QUtil::os_wrapper(this->filename + ": unread character",
		      ungetc(static_cast<unsigned char>(ch), this->file));
}