Commit | Line | Data |
---|---|---|
da7c5cc6 | 1 | /* |
0880b18e | 2 | * Copyright (c) 1982, 1986 Regents of the University of California. |
9db58063 | 3 | * All rights reserved. |
da7c5cc6 | 4 | * |
9db58063 KM |
5 | * %sccs.include.redist.c% |
6 | * | |
a85f307a | 7 | * @(#)subr_log.c 7.15 (Berkeley) %G% |
da7c5cc6 | 8 | */ |
c45816fa RC |
9 | |
10 | /* | |
11 | * Error log buffer for kernel printf's. | |
12 | */ | |
13 | ||
94368568 | 14 | #include "param.h" |
94368568 | 15 | #include "proc.h" |
0a23a89f | 16 | #include "vnode.h" |
94368568 JB |
17 | #include "ioctl.h" |
18 | #include "msgbuf.h" | |
19 | #include "file.h" | |
c45816fa RC |
20 | |
21 | #define LOG_RDPRI (PZERO + 1) | |
22 | ||
c45816fa RC |
23 | #define LOG_ASYNC 0x04 |
24 | #define LOG_RDWAIT 0x08 | |
25 | ||
26 | struct logsoftc { | |
27 | int sc_state; /* see above for possibilities */ | |
77f9c500 | 28 | struct selinfo sc_selp; /* process waiting on select call */ |
f9b02bae | 29 | int sc_pgid; /* process/group for async I/O */ |
c45816fa RC |
30 | } logsoftc; |
31 | ||
bd10af3f MK |
32 | int log_open; /* also used in log() */ |
33 | ||
0b355a6e | 34 | /*ARGSUSED*/ |
8429d022 | 35 | logopen(dev, flags, mode, p) |
c45816fa | 36 | dev_t dev; |
8429d022 MK |
37 | int flags, mode; |
38 | struct proc *p; | |
c45816fa | 39 | { |
9db58063 | 40 | register struct msgbuf *mbp = msgbufp; |
c45816fa | 41 | |
bd10af3f | 42 | if (log_open) |
18c9b20d | 43 | return (EBUSY); |
bd10af3f | 44 | log_open = 1; |
8429d022 | 45 | logsoftc.sc_pgid = p->p_pid; /* signal process only */ |
c45816fa RC |
46 | /* |
47 | * Potential race here with putchar() but since putchar should be | |
48 | * called by autoconf, msg_magic should be initialized by the time | |
49 | * we get here. | |
50 | */ | |
9db58063 | 51 | if (mbp->msg_magic != MSG_MAGIC) { |
c45816fa RC |
52 | register int i; |
53 | ||
9db58063 KM |
54 | mbp->msg_magic = MSG_MAGIC; |
55 | mbp->msg_bufx = mbp->msg_bufr = 0; | |
c45816fa | 56 | for (i=0; i < MSG_BSIZE; i++) |
9db58063 | 57 | mbp->msg_bufc[i] = 0; |
c45816fa | 58 | } |
18c9b20d | 59 | return (0); |
c45816fa RC |
60 | } |
61 | ||
0b355a6e | 62 | /*ARGSUSED*/ |
1a2bdfeb | 63 | logclose(dev, flag, mode, p) |
c45816fa | 64 | dev_t dev; |
1a2bdfeb CT |
65 | int flag, mode; |
66 | struct proc *p; | |
c45816fa | 67 | { |
77f9c500 | 68 | |
bd10af3f | 69 | log_open = 0; |
c45816fa | 70 | logsoftc.sc_state = 0; |
1a77c6b4 | 71 | return (0); |
c45816fa RC |
72 | } |
73 | ||
0b355a6e | 74 | /*ARGSUSED*/ |
f9b02bae | 75 | logread(dev, uio, flag) |
c45816fa RC |
76 | dev_t dev; |
77 | struct uio *uio; | |
f9b02bae | 78 | int flag; |
c45816fa | 79 | { |
9db58063 | 80 | register struct msgbuf *mbp = msgbufp; |
c45816fa | 81 | register long l; |
c45816fa RC |
82 | register int s; |
83 | int error = 0; | |
84 | ||
c45816fa | 85 | s = splhigh(); |
9db58063 | 86 | while (mbp->msg_bufr == mbp->msg_bufx) { |
f9b02bae | 87 | if (flag & IO_NDELAY) { |
c45816fa | 88 | splx(s); |
18c9b20d | 89 | return (EWOULDBLOCK); |
c45816fa RC |
90 | } |
91 | logsoftc.sc_state |= LOG_RDWAIT; | |
9db58063 | 92 | if (error = tsleep((caddr_t)mbp, LOG_RDPRI | PCATCH, |
86f4eb6e MT |
93 | "klog", 0)) { |
94 | splx(s); | |
95 | return (error); | |
96 | } | |
c45816fa RC |
97 | } |
98 | splx(s); | |
99 | logsoftc.sc_state &= ~LOG_RDWAIT; | |
100 | ||
101 | while (uio->uio_resid > 0) { | |
9db58063 | 102 | l = mbp->msg_bufx - mbp->msg_bufr; |
c45816fa | 103 | if (l < 0) |
9db58063 | 104 | l = MSG_BSIZE - mbp->msg_bufr; |
8011f5df | 105 | l = MIN(l, uio->uio_resid); |
b52a4e53 | 106 | if (l == 0) |
18c9b20d | 107 | break; |
9db58063 | 108 | error = uiomove((caddr_t)&mbp->msg_bufc[mbp->msg_bufr], |
c4ec2128 | 109 | (int)l, uio); |
c45816fa RC |
110 | if (error) |
111 | break; | |
9db58063 KM |
112 | mbp->msg_bufr += l; |
113 | if (mbp->msg_bufr < 0 || mbp->msg_bufr >= MSG_BSIZE) | |
114 | mbp->msg_bufr = 0; | |
c45816fa | 115 | } |
18c9b20d | 116 | return (error); |
c45816fa RC |
117 | } |
118 | ||
0b355a6e | 119 | /*ARGSUSED*/ |
8429d022 | 120 | logselect(dev, rw, p) |
c45816fa RC |
121 | dev_t dev; |
122 | int rw; | |
8429d022 | 123 | struct proc *p; |
c45816fa RC |
124 | { |
125 | int s = splhigh(); | |
126 | ||
127 | switch (rw) { | |
128 | ||
129 | case FREAD: | |
9db58063 | 130 | if (msgbufp->msg_bufr != msgbufp->msg_bufx) { |
b52a4e53 MK |
131 | splx(s); |
132 | return (1); | |
133 | } | |
77f9c500 | 134 | selrecord(p, &logsoftc.sc_selp); |
c45816fa | 135 | break; |
c45816fa RC |
136 | } |
137 | splx(s); | |
18c9b20d | 138 | return (0); |
c45816fa RC |
139 | } |
140 | ||
141 | logwakeup() | |
142 | { | |
f9b02bae | 143 | struct proc *p; |
c45816fa | 144 | |
bd10af3f MK |
145 | if (!log_open) |
146 | return; | |
77f9c500 | 147 | selwakeup(&logsoftc.sc_selp); |
f9b02bae MK |
148 | if (logsoftc.sc_state & LOG_ASYNC) { |
149 | if (logsoftc.sc_pgid < 0) | |
fa1aff05 | 150 | gsignal(-logsoftc.sc_pgid, SIGIO); |
f9b02bae MK |
151 | else if (p = pfind(logsoftc.sc_pgid)) |
152 | psignal(p, SIGIO); | |
153 | } | |
c45816fa | 154 | if (logsoftc.sc_state & LOG_RDWAIT) { |
9db58063 | 155 | wakeup((caddr_t)msgbufp); |
c45816fa RC |
156 | logsoftc.sc_state &= ~LOG_RDWAIT; |
157 | } | |
158 | } | |
159 | ||
160 | /*ARGSUSED*/ | |
1a2bdfeb CT |
161 | logioctl(dev, com, data, flag, p) |
162 | dev_t dev; | |
163 | int com; | |
c45816fa | 164 | caddr_t data; |
1a2bdfeb CT |
165 | int flag; |
166 | struct proc *p; | |
c45816fa RC |
167 | { |
168 | long l; | |
169 | int s; | |
170 | ||
171 | switch (com) { | |
172 | ||
173 | /* return number of characters immediately available */ | |
174 | case FIONREAD: | |
175 | s = splhigh(); | |
9db58063 | 176 | l = msgbufp->msg_bufx - msgbufp->msg_bufr; |
c45816fa RC |
177 | splx(s); |
178 | if (l < 0) | |
179 | l += MSG_BSIZE; | |
a85f307a | 180 | *(int *)data = l; |
c45816fa RC |
181 | break; |
182 | ||
183 | case FIONBIO: | |
c45816fa RC |
184 | break; |
185 | ||
186 | case FIOASYNC: | |
187 | if (*(int *)data) | |
188 | logsoftc.sc_state |= LOG_ASYNC; | |
189 | else | |
190 | logsoftc.sc_state &= ~LOG_ASYNC; | |
191 | break; | |
192 | ||
f9b02bae | 193 | case TIOCSPGRP: |
8fe87cbb | 194 | logsoftc.sc_pgid = *(int *)data; |
c45816fa RC |
195 | break; |
196 | ||
197 | case TIOCGPGRP: | |
f9b02bae | 198 | *(int *)data = logsoftc.sc_pgid; |
c45816fa RC |
199 | break; |
200 | ||
201 | default: | |
18c9b20d | 202 | return (-1); |
c45816fa | 203 | } |
18c9b20d | 204 | return (0); |
c45816fa | 205 | } |