summaryrefslogtreecommitdiff
path: root/vcs-svn/line_buffer.c
blob: 57cc1cec033f638e6d408370039b46b653289e84 (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
/*
 * Licensed under a two-clause BSD-style license.
 * See LICENSE for details.
 */
 
#include "git-compat-util.h"
#include "line_buffer.h"
#include "strbuf.h"
 
#define COPY_BUFFER_LEN 4096
 
int buffer_init(struct line_buffer *buf, const char *filename)
{
	buf->infile = filename ? fopen(filename, "r") : stdin;
	if (!buf->infile)
		return -1;
	return 0;
}
 
int buffer_fdinit(struct line_buffer *buf, int fd)
{
	buf->infile = fdopen(fd, "r");
	if (!buf->infile)
		return -1;
	return 0;
}
 
int buffer_tmpfile_init(struct line_buffer *buf)
{
	buf->infile = tmpfile();
	if (!buf->infile)
		return -1;
	return 0;
}
 
int buffer_deinit(struct line_buffer *buf)
{
	int err;
	if (buf->infile == stdin)
		return ferror(buf->infile);
	err = ferror(buf->infile);
	err |= fclose(buf->infile);
	return err;
}
 
FILE *buffer_tmpfile_rewind(struct line_buffer *buf)
{
	rewind(buf->infile);
	return buf->infile;
}
 
long buffer_tmpfile_prepare_to_read(struct line_buffer *buf)
{
	long pos = ftell(buf->infile);
	if (pos < 0)
		return error("ftell error: %s", strerror(errno));
	if (fseek(buf->infile, 0, SEEK_SET))
		return error("seek error: %s", strerror(errno));
	return pos;
}
 
int buffer_ferror(struct line_buffer *buf)
{
	return ferror(buf->infile);
}
 
int buffer_read_char(struct line_buffer *buf)
{
	return fgetc(buf->infile);
}
 
/* Read a line without trailing newline. */
char *buffer_read_line(struct line_buffer *buf)
{
	char *end;
	if (!fgets(buf->line_buffer, sizeof(buf->line_buffer), buf->infile))
		/* Error or data exhausted. */
		return NULL;
	end = buf->line_buffer + strlen(buf->line_buffer);
	if (end[-1] == '\n')
		end[-1] = '\0';
	else if (feof(buf->infile))
		; /* No newline at end of file.  That's fine. */
	else
		/*
		 * Line was too long.
		 * There is probably a saner way to deal with this,
		 * but for now let's return an error.
		 */
		return NULL;
	return buf->line_buffer;
}
 
size_t buffer_read_binary(struct line_buffer *buf,
				struct strbuf *sb, size_t size)
{
	return strbuf_fread(sb, size, buf->infile);
}
 
off_t buffer_copy_bytes(struct line_buffer *buf, off_t nbytes)
{
	char byte_buffer[COPY_BUFFER_LEN];
	off_t done = 0;
	while (done < nbytes && !feof(buf->infile) && !ferror(buf->infile)) {
		off_t len = nbytes - done;
		size_t in = len < COPY_BUFFER_LEN ? len : COPY_BUFFER_LEN;
		in = fread(byte_buffer, 1, in, buf->infile);
		done += in;
		fwrite(byte_buffer, 1, in, stdout);
		if (ferror(stdout))
			return done + buffer_skip_bytes(buf, nbytes - done);
	}
	return done;
}
 
off_t buffer_skip_bytes(struct line_buffer *buf, off_t nbytes)
{
	char byte_buffer[COPY_BUFFER_LEN];
	off_t done = 0;
	while (done < nbytes && !feof(buf->infile) && !ferror(buf->infile)) {
		off_t len = nbytes - done;
		size_t in = len < COPY_BUFFER_LEN ? len : COPY_BUFFER_LEN;
		done += fread(byte_buffer, 1, in, buf->infile);
	}
	return done;
}