1 /* Public domain. */
2
3 #include "buffer.h"
4 #include "byte.h"
5 #include "error.h"
6
oneread(int (* op)(),int fd,char * buf,unsigned int len)7 static 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
getthis(buffer * s,char * buf,unsigned int len)18 static 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
buffer_feed(buffer * s)27 int 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
buffer_bget(buffer * s,char * buf,unsigned int len)40 int 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
buffer_get(buffer * s,char * buf,unsigned int len)50 int 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
buffer_peek(buffer * s)60 char *buffer_peek(buffer *s)
61 {
62 return s->x + s->n;
63 }
64
buffer_seek(buffer * s,unsigned int len)65 void buffer_seek(buffer *s,unsigned int len)
66 {
67 s->n += len;
68 s->p -= len;
69 }
70