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