1/* Public domain. */
 2
 3#include "buffer.h"
 4#include "byte.h"
 5#include "error.h"
 6
 7static int oneread(int (*op)(),int fd,char *buf,unsigned int len)
 8{
 9  int r;
10
11  for (;;) {
12    r = op(fd,buf,len);
13    if (r == -1) if (errno == error_intr) continue;
14    return r;
15  }
16}
17
18static int getthis(buffer *s,char *buf,unsigned int len)
19{
20  if (len > s->p) len = s->p;
21  s->p -= len;
22  byte_copy(buf,len,s->x + s->n);
23  s->n += len;
24  return len;
25}
26
27int buffer_feed(buffer *s)
28{
29  int r;
30
31  if (s->p) return s->p;
32  r = oneread(s->op,s->fd,s->x,s->n);
33  if (r <= 0) return r;
34  s->p = r;
35  s->n -= r;
36  if (s->n > 0) byte_copyr(s->x + s->n,r,s->x);
37  return r;
38}
39
40int buffer_bget(buffer *s,char *buf,unsigned int len)
41{
42  int r;
43 
44  if (s->p > 0) return getthis(s,buf,len);
45  if (s->n <= len) return oneread(s->op,s->fd,buf,s->n);
46  r = buffer_feed(s); if (r <= 0) return r;
47  return getthis(s,buf,len);
48}
49
50int buffer_get(buffer *s,char *buf,unsigned int len)
51{
52  int r;
53 
54  if (s->p > 0) return getthis(s,buf,len);
55  if (s->n <= len) return oneread(s->op,s->fd,buf,len);
56  r = buffer_feed(s); if (r <= 0) return r;
57  return getthis(s,buf,len);
58}
59
60char *buffer_peek(buffer *s)
61{
62  return s->x + s->n;
63}
64
65void buffer_seek(buffer *s,unsigned int len)
66{
67  s->n += len;
68  s->p -= len;
69}