summaryrefslogtreecommitdiff
path: root/fitz/stm_read.c
blob: 3bdddade1fdc54aa2f989695a59f6614cb9a00f5 (plain)
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
#include "fitz.h"

int
fz_read(fz_stream *stm, unsigned char *buf, int len)
{
	int avail, count;

	avail = stm->wp - stm->rp;
	if (avail)
	{
		count = MIN(len, avail);
		memcpy(buf, stm->rp, count);
		stm->rp += count;
	}
	else
	{
		count = 0;
	}

	if (stm->dead)
		return count;

	while (len > count)
	{
		int n = stm->read(stm, buf + count, len - count);
		if (n < 0)
		{
			stm->dead = 1;
			return fz_rethrow(n, "read error");
		}
		if (n == 0)
			break;
		stm->pos += n;
		count += n;
	}

	return count;
}

void
fz_fillbuffer(fz_stream *stm)
{
	int n;

	assert(stm->rp == stm->wp);

	n = fz_read(stm, stm->bp, stm->ep - stm->bp);
	if (n < 0)
		fz_catch(n, "read error; treating as end of file");
	else
	{
		stm->rp = stm->bp;
		stm->wp = stm->bp + n;
	}
}

fz_error
fz_readall(fz_buffer **bufp, fz_stream *stm)
{
	fz_buffer *buf;
	int n;

	buf = fz_newbuffer(16 * 1024);

	while (1)
	{
		if (buf->len == buf->cap)
			fz_growbuffer(buf);

		n = fz_read(stm, buf->data + buf->len, buf->cap - buf->len);
		if (n < 0)
		{
			fz_dropbuffer(buf);
			return fz_rethrow(n, "read error");
		}
		if (n == 0)
			break;

		buf->len += n;
	}

	*bufp = buf;
	return fz_okay;
}

void
fz_readline(fz_stream *stm, char *mem, int n)
{
	char *s = mem;
	int c = EOF;
	while (n > 1)
	{
		c = fz_readbyte(stm);
		if (c == EOF)
			break;
		if (c == '\r') {
			c = fz_peekbyte(stm);
			if (c == '\n')
				fz_readbyte(stm);
			break;
		}
		if (c == '\n')
			break;
		*s++ = c;
		n--;
	}
	if (n)
		*s = '\0';
}

int
fz_tell(fz_stream *stm)
{
	return stm->pos - (stm->wp - stm->rp);
}

void
fz_seek(fz_stream *stm, int offset, int whence)
{
	if (stm->seek)
		stm->seek(stm, offset, whence);
	else if (whence != 2)
	{
		if (whence == 0)
			offset -= fz_tell(stm);
		if (offset < 0)
			fz_warn("cannot seek backwards");
		/* dog slow, but rare enough */
		while (offset-- > 0)
			fz_readbyte(stm);
	}
	else
		fz_warn("cannot seek");
}