1 /*
2 * Licensed under a two-clause BSD-style license.
3 * See LICENSE for details.
4 */
6 #include "git-compat-util.h"
7 #include "line_buffer.h"
8 #include "strbuf.h"
10 #define COPY_BUFFER_LEN 4096
12 int buffer_init(struct line_buffer *buf, const char *filename)
13 {
14 buf->infile = filename ? fopen(filename, "r") : stdin;
15 if (!buf->infile)
16 return -1;
17 return 0;
18 }
20 int buffer_deinit(struct line_buffer *buf)
21 {
22 int err;
23 if (buf->infile == stdin)
24 return ferror(buf->infile);
25 err = ferror(buf->infile);
26 err |= fclose(buf->infile);
27 return err;
28 }
30 int buffer_read_char(struct line_buffer *buf)
31 {
32 return fgetc(buf->infile);
33 }
35 /* Read a line without trailing newline. */
36 char *buffer_read_line(struct line_buffer *buf)
37 {
38 char *end;
39 if (!fgets(buf->line_buffer, sizeof(buf->line_buffer), buf->infile))
40 /* Error or data exhausted. */
41 return NULL;
42 end = buf->line_buffer + strlen(buf->line_buffer);
43 if (end[-1] == '\n')
44 end[-1] = '\0';
45 else if (feof(buf->infile))
46 ; /* No newline at end of file. That's fine. */
47 else
48 /*
49 * Line was too long.
50 * There is probably a saner way to deal with this,
51 * but for now let's return an error.
52 */
53 return NULL;
54 return buf->line_buffer;
55 }
57 char *buffer_read_string(struct line_buffer *buf, uint32_t len)
58 {
59 strbuf_reset(&buf->blob_buffer);
60 strbuf_fread(&buf->blob_buffer, len, buf->infile);
61 return ferror(buf->infile) ? NULL : buf->blob_buffer.buf;
62 }
64 void buffer_read_binary(struct line_buffer *buf,
65 struct strbuf *sb, uint32_t size)
66 {
67 strbuf_fread(sb, size, buf->infile);
68 }
70 void buffer_copy_bytes(struct line_buffer *buf, uint32_t len)
71 {
72 char byte_buffer[COPY_BUFFER_LEN];
73 uint32_t in;
74 while (len > 0 && !feof(buf->infile) && !ferror(buf->infile)) {
75 in = len < COPY_BUFFER_LEN ? len : COPY_BUFFER_LEN;
76 in = fread(byte_buffer, 1, in, buf->infile);
77 len -= in;
78 fwrite(byte_buffer, 1, in, stdout);
79 if (ferror(stdout)) {
80 buffer_skip_bytes(buf, len);
81 return;
82 }
83 }
84 }
86 void buffer_skip_bytes(struct line_buffer *buf, uint32_t len)
87 {
88 char byte_buffer[COPY_BUFFER_LEN];
89 uint32_t in;
90 while (len > 0 && !feof(buf->infile) && !ferror(buf->infile)) {
91 in = len < COPY_BUFFER_LEN ? len : COPY_BUFFER_LEN;
92 in = fread(byte_buffer, 1, in, buf->infile);
93 len -= in;
94 }
95 }
97 void buffer_reset(struct line_buffer *buf)
98 {
99 strbuf_release(&buf->blob_buffer);
100 }