xref: /unit/src/nxt_sendbuf.h (revision 771:f349b2d68e75)
1 
2 /*
3  * Copyright (C) Igor Sysoev
4  * Copyright (C) NGINX, Inc.
5  */
6 
7 #ifndef _NXT_SENDBUF_H_INCLUDED_
8 #define _NXT_SENDBUF_H_INCLUDED_
9 
10 
11 /*
12  * The sendbuf interface is intended to send a buffer chain to a connection.
13  * It uses sendfile interface if available.  Otherwise it can send only
14  * memory buffers, so file buffers must be read in memory in advance.
15  *
16  * The sendbuf interface sets c->socket.write_ready to appropriate state
17  * and returns:
18  *
19  *   N > 0      if sendbuf sent N bytes.
20  *
21  *   0          if sendbuf was interrupted (EINTR and so on),
22  *              or sendbuf sent previously buffered data,
23  *              or single sync buffer has been encountered.
24  *              In all these cases sendbuf is ready to continue
25  *              operation, unless c->socket.write_ready is cleared.
26  *
27  *   NXT_AGAIN  if sendbuf did not send any bytes.
28  *
29  *   NXT_ERROR  if there was erorr.
30  *
31  * The sendbuf limit is size_t type since size_t is large enough and many
32  * sendfile implementations do not support anyway sending more than size_t
33  * at once.  The limit support is located at the sendbuf level otherwise
34  * an additional limited chain must be created on each sendbuf call.
35  */
36 
37 
38 typedef struct {
39     nxt_buf_t     *buf;
40     void          *tls;
41     nxt_socket_t  socket;
42     nxt_err_t     error;
43     nxt_off_t     sent;
44     size_t        size;
45     size_t        limit;
46 
47     uint8_t       ready;   /* 1 bit */
48     uint8_t       once;    /* 1 bit */
49     uint8_t       sync;    /* 1 bit */
50     uint8_t       last;    /* 1 bit */
51 } nxt_sendbuf_t;
52 
53 
54 typedef struct {
55     nxt_buf_t    *buf;
56     nxt_iobuf_t  *iobuf;
57     nxt_uint_t   niov;
58 
59     uint32_t     nmax;
60     uint8_t      sync;   /* 1 bit */
61     uint8_t      last;   /* 1 bit */
62     uint8_t      limit_reached;
63     uint8_t      nmax_reached;
64 
65     size_t       size;
66     size_t       limit;
67 } nxt_sendbuf_coalesce_t;
68 
69 
70 #if (NXT_HAVE_LINUX_SENDFILE)
71 #define NXT_HAVE_SENDFILE  1
72 ssize_t nxt_linux_event_conn_io_sendfile(nxt_conn_t *c, nxt_buf_t *b,
73     size_t limit);
74 #endif
75 
76 #if (NXT_HAVE_FREEBSD_SENDFILE)
77 #define NXT_HAVE_SENDFILE  1
78 ssize_t nxt_freebsd_event_conn_io_sendfile(nxt_conn_t *c, nxt_buf_t *b,
79     size_t limit);
80 #endif
81 
82 #if (NXT_HAVE_SOLARIS_SENDFILEV)
83 #define NXT_HAVE_SENDFILE  1
84 ssize_t nxt_solaris_event_conn_io_sendfilev(nxt_conn_t *c, nxt_buf_t *b,
85     size_t limit);
86 #endif
87 
88 #if (NXT_HAVE_MACOSX_SENDFILE)
89 #define NXT_HAVE_SENDFILE  1
90 ssize_t nxt_macosx_event_conn_io_sendfile(nxt_conn_t *c, nxt_buf_t *b,
91     size_t limit);
92 #endif
93 
94 #if (NXT_HAVE_AIX_SEND_FILE)
95 #define NXT_HAVE_SENDFILE  1
96 ssize_t nxt_aix_event_conn_io_send_file(nxt_conn_t *c, nxt_buf_t *b,
97     size_t limit);
98 #endif
99 
100 #if (NXT_HAVE_HPUX_SENDFILE)
101 #define NXT_HAVE_SENDFILE  1
102 ssize_t nxt_hpux_event_conn_io_sendfile(nxt_conn_t *c, nxt_buf_t *b,
103     size_t limit);
104 #endif
105 
106 ssize_t nxt_event_conn_io_sendbuf(nxt_conn_t *c, nxt_buf_t *b,
107     size_t limit);
108 
109 
110 nxt_uint_t nxt_sendbuf_mem_coalesce0(nxt_task_t *task, nxt_sendbuf_t *sb,
111     struct iovec *iov, nxt_uint_t niov_max);
112 nxt_uint_t nxt_sendbuf_mem_coalesce(nxt_task_t *task,
113     nxt_sendbuf_coalesce_t *sb);
114 size_t nxt_sendbuf_file_coalesce(nxt_sendbuf_coalesce_t *sb);
115 
116 /*
117  * Auxiliary nxt_sendbuf_copy_coalesce() interface copies small memory
118  * buffers into internal buffer before output.  It is intended for
119  * SSL/TLS libraries which lack vector I/O interface yet add noticeable
120  * overhead to each SSL/TLS record.
121  */
122 ssize_t nxt_sendbuf_copy_coalesce(nxt_conn_t *c, nxt_buf_mem_t *bm,
123     nxt_buf_t *b, size_t limit);
124 
125 nxt_buf_t *nxt_sendbuf_update(nxt_buf_t *b, size_t sent);
126 nxt_buf_t *nxt_sendbuf_completion(nxt_task_t *task, nxt_work_queue_t *wq,
127     nxt_buf_t *b);
128 void nxt_sendbuf_drain(nxt_task_t *task, nxt_work_queue_t *wq, nxt_buf_t *b);
129 
130 
131 #endif /* _NXT_SENDBUF_H_INCLUDED_ */
132