3 * $Id: selbuf.c,v 1.4 2000/06/17 10:38:14 mdw Exp $
5 * Line-buffering select handler
7 * (c) 1999 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of the mLib utilities library.
14 * mLib is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU Library General Public License as
16 * published by the Free Software Foundation; either version 2 of the
17 * License, or (at your option) any later version.
19 * mLib is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU Library General Public License for more details.
24 * You should have received a copy of the GNU Library General Public
25 * License along with mLib; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
30 /*----- Revision history --------------------------------------------------*
33 * Revision 1.4 2000/06/17 10:38:14 mdw
34 * Add support for variable buffer sizes.
36 * Revision 1.3 1999/05/22 13:41:00 mdw
37 * Fix end-of-file detection and error handling.
39 * Revision 1.2 1999/05/17 20:36:50 mdw
40 * Make the magical constants for the buffer flags uppercase.
42 * Revision 1.1 1999/05/14 21:01:15 mdw
43 * Integrated `select' handling bits from the background resolver project.
47 /*----- Header files ------------------------------------------------------*/
54 #include <sys/types.h>
62 /*----- Main code ---------------------------------------------------------*/
64 /* --- @selbuf_enable@ --- *
66 * Arguments: @selbuf *b@ = pointer to buffer block
70 * Use: Enables a buffer for reading, and emits any queued lines
71 * to the buffer's owner.
74 void selbuf_enable(selbuf *b)
76 if (!(b->b.f & LBUF_ENABLE)) {
77 b->b.f |= LBUF_ENABLE;
78 sel_addfile(&b->reader);
79 lbuf_flush(&b->b, 0, 0);
83 /* --- @selbuf_disable@ --- *
85 * Arguments: @selbuf *b@ = pointer to a buffer block
89 * Use: Disables a buffer. It won't be read from until it's
93 void selbuf_disable(selbuf *b)
95 if (b->b.f & LBUF_ENABLE) {
96 b->b.f &= ~LBUF_ENABLE;
97 sel_rmfile(&b->reader);
101 /* --- @selbuf_read@ --- *
103 * Arguments: @int fd@ = file descriptor to read from
104 * @int mode@ = what we can do to the file
105 * @void *vp@ = pointer to buffer context
109 * Use: Acts on the result of a @select@ call.
112 static void selbuf_read(int fd, unsigned mode, void *vp)
119 sz = lbuf_free(&b->b, &p);
124 lbuf_flush(&b->b, p, n);
125 else switch (errno) {
128 #if EAGAIN != EWOULDBLOCK
137 /* --- @selbuf_setsize@ --- *
139 * Arguments: @selbuf *b@ = pointer to buffer block
140 * @size_t sz@ = size of buffer
144 * Use: Sets the size of the buffer used for reading lines.
147 void selbuf_setsize(selbuf *b, size_t sz)
149 lbuf_setsize(&b->b, sz);
152 /* --- @selbuf_init@ --- *
154 * Arguments: @selbuf *b@ = pointer to buffer block
155 * @sel_state *s@ = pointer to select state to attach to
156 * @int fd@ = file descriptor to listen to
157 * @void (*func)(char *s, void *p)@ = function to call
158 * @void *p@ = argument for function
162 * Use: Initializes a buffer block.
165 void selbuf_init(selbuf *b,
168 void (*func)(char */*s*/, void */*p*/),
171 lbuf_init(&b->b, func, p);
172 b->b.f &= ~LBUF_ENABLE;
173 sel_initfile(s, &b->reader, fd, SEL_READ, selbuf_read, b);
177 /* --- @selbuf_destroy@ --- *
179 * Arguments: @selbuf *b@ = pointer to buffer block
183 * Use: Deallocates a line buffer and frees any resources it owned.
186 void selbuf_destroy(selbuf *b)
192 /*----- That's all, folks -------------------------------------------------*/