2 * Copyright (C) 1996-2005 The Free Software Foundation, Inc.
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2, or (at your option)
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
15 /* Declarations concerning the buffer data structure. */
17 #if defined (SERVER_SUPPORT) || defined (CLIENT_SUPPORT)
20 * We must read data from a child process and send it across the
21 * network. We do not want to block on writing to the network, so we
22 * store the data from the child process in memory. A BUFFER
23 * structure holds the status of one communication, and uses a linked
24 * list of buffer_data structures to hold data.
30 struct buffer_data *data;
32 /* Last buffer on data chain. */
33 struct buffer_data *last;
35 /* Nonzero if the buffer is in nonblocking mode. */
38 /* Functions must be provided to transfer data in and out of the
39 buffer. Either the input or output field must be set, but not
42 /* Read data into the buffer DATA. There is room for up to SIZE
43 bytes. In blocking mode, wait until some input, at least NEED
44 bytes, is available (NEED may be 0 but that is the same as NEED
45 == 1). In non-blocking mode return immediately no matter how
46 much input is available; NEED is ignored. Return 0 on success,
47 or -1 on end of file, or an errno code. Set the number of
50 If there are a nonzero number of bytes available, less than NEED,
51 followed by end of file, just read those bytes and return 0. */
52 int (*input) PROTO((void *closure, char *data, int need, int size,
55 /* Write data. This should write up to HAVE bytes from DATA.
56 This should return 0 on success, or an errno code. It should
57 set the number of bytes written in *WROTE. */
58 int (*output) PROTO((void *closure, const char *data, int have,
61 /* Flush any data which may be buffered up after previous calls to
62 OUTPUT. This should return 0 on success, or an errno code. */
63 int (*flush) PROTO((void *closure));
65 /* Change the blocking mode of the underlying communication
66 stream. If BLOCK is non-zero, it should be placed into
67 blocking mode. Otherwise, it should be placed into
68 non-blocking mode. This should return 0 on success, or an
70 int (*block) PROTO ((void *closure, int block));
72 /* Shut down the communication stream. This does not mean that it
73 should be closed. It merely means that no more data will be
74 read or written, and that any final processing that is
75 appropriate should be done at this point. This may be NULL.
76 It should return 0 on success, or an errno code. This entry
77 point exists for the compression code. */
78 int (*shutdown) PROTO((struct buffer *));
80 /* This field is passed to the INPUT, OUTPUT, and BLOCK functions. */
83 /* Function to call if we can't allocate memory. */
84 void (*memory_error) PROTO((struct buffer *));
87 /* Data is stored in lists of these structures. */
91 /* Next buffer in linked list. */
92 struct buffer_data *next;
95 * A pointer into the data area pointed to by the text field. This
96 * is where to find data that has not yet been written out.
100 /* The number of data bytes found at BUFP. */
104 * Actual buffer. This never changes after the structure is
105 * allocated. The buffer is BUFFER_DATA_SIZE bytes.
110 /* The size we allocate for each buffer_data structure. */
111 #define BUFFER_DATA_SIZE (4096)
113 /* The type of a function passed as a memory error handler. */
114 typedef void (*BUFMEMERRPROC) PROTO ((struct buffer *));
116 extern struct buffer *buf_initialize PROTO((int (*) (void *, char *, int,
118 int (*) (void *, const char *,
121 int (*) (void *, int),
122 int (*) (struct buffer *),
123 void (*) (struct buffer *),
125 extern void buf_free PROTO((struct buffer *));
126 extern struct buffer *buf_nonio_initialize PROTO((void (*) (struct buffer *)));
127 extern struct buffer *stdio_buffer_initialize
128 PROTO((FILE *, int, int, void (*) (struct buffer *)));
129 extern FILE *stdio_buffer_get_file PROTO((struct buffer *));
130 extern struct buffer *compress_buffer_initialize
131 PROTO((struct buffer *, int, int, void (*) (struct buffer *)));
132 extern struct buffer *packetizing_buffer_initialize
133 PROTO((struct buffer *, int (*) (void *, const char *, char *, int),
134 int (*) (void *, const char *, char *, int, int *), void *,
135 void (*) (struct buffer *)));
136 extern int buf_empty PROTO((struct buffer *));
137 extern int buf_empty_p PROTO((struct buffer *));
138 extern void buf_output PROTO((struct buffer *, const char *, int));
139 extern void buf_output0 PROTO((struct buffer *, const char *));
140 extern void buf_append_char PROTO((struct buffer *, int));
141 extern int buf_send_output PROTO((struct buffer *));
142 extern int buf_flush PROTO((struct buffer *, int));
143 extern int set_nonblock PROTO((struct buffer *));
144 extern int set_block PROTO((struct buffer *));
145 extern int buf_send_counted PROTO((struct buffer *));
146 extern int buf_send_special_count PROTO((struct buffer *, int));
147 extern void buf_append_data PROTO((struct buffer *,
148 struct buffer_data *,
149 struct buffer_data *));
150 extern void buf_append_buffer PROTO((struct buffer *, struct buffer *));
151 extern int buf_read_file PROTO((FILE *, long, struct buffer_data **,
152 struct buffer_data **));
153 extern int buf_read_file_to_eof PROTO((FILE *, struct buffer_data **,
154 struct buffer_data **));
155 extern int buf_input_data PROTO((struct buffer *, int *));
156 extern int buf_read_line PROTO((struct buffer *, char **, int *));
157 extern int buf_read_data PROTO((struct buffer *, int, char **, int *));
158 extern void buf_copy_lines PROTO((struct buffer *, struct buffer *, int));
159 extern int buf_copy_counted PROTO((struct buffer *, struct buffer *, int *));
160 extern int buf_chain_length PROTO((struct buffer_data *));
161 extern int buf_length PROTO((struct buffer *));
162 extern int buf_shutdown PROTO((struct buffer *));
164 #ifdef SERVER_FLOWCONTROL
165 extern int buf_count_mem PROTO((struct buffer *));
166 #endif /* SERVER_FLOWCONTROL */
168 #endif /* defined (SERVER_SUPPORT) || defined (CLIENT_SUPPORT) */