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 /* Read a line without trailing newline. */
31 char *buffer_read_line(struct line_buffer *buf)
32 {
33 char *end;
34 if (!fgets(buf->line_buffer, sizeof(buf->line_buffer), buf->infile))
35 /* Error or data exhausted. */
36 return NULL;
37 end = buf->line_buffer + strlen(buf->line_buffer);
38 if (end[-1] == '\n')
39 end[-1] = '\0';
40 else if (feof(buf->infile))
41 ; /* No newline at end of file. That's fine. */
42 else
43 /*
44 * Line was too long.
45 * There is probably a saner way to deal with this,
46 * but for now let's return an error.
47 */
48 return NULL;
49 return buf->line_buffer;
50 }
52 char *buffer_read_string(struct line_buffer *buf, uint32_t len)
53 {
54 strbuf_reset(&buf->blob_buffer);
55 strbuf_fread(&buf->blob_buffer, len, buf->infile);
56 return ferror(buf->infile) ? NULL : buf->blob_buffer.buf;
57 }
59 void buffer_copy_bytes(struct line_buffer *buf, uint32_t len)
60 {
61 char byte_buffer[COPY_BUFFER_LEN];
62 uint32_t in;
63 while (len > 0 && !feof(buf->infile) && !ferror(buf->infile)) {
64 in = len < COPY_BUFFER_LEN ? len : COPY_BUFFER_LEN;
65 in = fread(byte_buffer, 1, in, buf->infile);
66 len -= in;
67 fwrite(byte_buffer, 1, in, stdout);
68 if (ferror(stdout)) {
69 buffer_skip_bytes(buf, len);
70 return;
71 }
72 }
73 }
75 void buffer_skip_bytes(struct line_buffer *buf, uint32_t len)
76 {
77 char byte_buffer[COPY_BUFFER_LEN];
78 uint32_t in;
79 while (len > 0 && !feof(buf->infile) && !ferror(buf->infile)) {
80 in = len < COPY_BUFFER_LEN ? len : COPY_BUFFER_LEN;
81 in = fread(byte_buffer, 1, in, buf->infile);
82 len -= in;
83 }
84 }
86 void buffer_reset(struct line_buffer *buf)
87 {
88 strbuf_release(&buf->blob_buffer);
89 }