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 | * | |
8429d022 | 7 | * @(#)subr_log.c 7.11 (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 */ | |
28 | struct proc *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*/ |
c45816fa RC |
63 | logclose(dev, flag) |
64 | dev_t dev; | |
65 | { | |
bd10af3f | 66 | log_open = 0; |
c45816fa RC |
67 | logsoftc.sc_state = 0; |
68 | logsoftc.sc_selp = 0; | |
c45816fa RC |
69 | } |
70 | ||
0b355a6e | 71 | /*ARGSUSED*/ |
f9b02bae | 72 | logread(dev, uio, flag) |
c45816fa RC |
73 | dev_t dev; |
74 | struct uio *uio; | |
f9b02bae | 75 | int flag; |
c45816fa | 76 | { |
9db58063 | 77 | register struct msgbuf *mbp = msgbufp; |
c45816fa | 78 | register long l; |
c45816fa RC |
79 | register int s; |
80 | int error = 0; | |
81 | ||
c45816fa | 82 | s = splhigh(); |
9db58063 | 83 | while (mbp->msg_bufr == mbp->msg_bufx) { |
f9b02bae | 84 | if (flag & IO_NDELAY) { |
c45816fa | 85 | splx(s); |
18c9b20d | 86 | return (EWOULDBLOCK); |
c45816fa RC |
87 | } |
88 | logsoftc.sc_state |= LOG_RDWAIT; | |
9db58063 | 89 | if (error = tsleep((caddr_t)mbp, LOG_RDPRI | PCATCH, |
86f4eb6e MT |
90 | "klog", 0)) { |
91 | splx(s); | |
92 | return (error); | |
93 | } | |
c45816fa RC |
94 | } |
95 | splx(s); | |
96 | logsoftc.sc_state &= ~LOG_RDWAIT; | |
97 | ||
98 | while (uio->uio_resid > 0) { | |
9db58063 | 99 | l = mbp->msg_bufx - mbp->msg_bufr; |
c45816fa | 100 | if (l < 0) |
9db58063 | 101 | l = MSG_BSIZE - mbp->msg_bufr; |
8011f5df | 102 | l = MIN(l, uio->uio_resid); |
b52a4e53 | 103 | if (l == 0) |
18c9b20d | 104 | break; |
9db58063 | 105 | error = uiomove((caddr_t)&mbp->msg_bufc[mbp->msg_bufr], |
c4ec2128 | 106 | (int)l, uio); |
c45816fa RC |
107 | if (error) |
108 | break; | |
9db58063 KM |
109 | mbp->msg_bufr += l; |
110 | if (mbp->msg_bufr < 0 || mbp->msg_bufr >= MSG_BSIZE) | |
111 | mbp->msg_bufr = 0; | |
c45816fa | 112 | } |
18c9b20d | 113 | return (error); |
c45816fa RC |
114 | } |
115 | ||
0b355a6e | 116 | /*ARGSUSED*/ |
8429d022 | 117 | logselect(dev, rw, p) |
c45816fa RC |
118 | dev_t dev; |
119 | int rw; | |
8429d022 | 120 | struct proc *p; |
c45816fa RC |
121 | { |
122 | int s = splhigh(); | |
123 | ||
124 | switch (rw) { | |
125 | ||
126 | case FREAD: | |
9db58063 | 127 | if (msgbufp->msg_bufr != msgbufp->msg_bufx) { |
b52a4e53 MK |
128 | splx(s); |
129 | return (1); | |
130 | } | |
8429d022 | 131 | logsoftc.sc_selp = p; |
c45816fa | 132 | break; |
c45816fa RC |
133 | } |
134 | splx(s); | |
18c9b20d | 135 | return (0); |
c45816fa RC |
136 | } |
137 | ||
138 | logwakeup() | |
139 | { | |
f9b02bae | 140 | struct proc *p; |
c45816fa | 141 | |
bd10af3f MK |
142 | if (!log_open) |
143 | return; | |
c45816fa RC |
144 | if (logsoftc.sc_selp) { |
145 | selwakeup(logsoftc.sc_selp, 0); | |
146 | logsoftc.sc_selp = 0; | |
147 | } | |
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*/ | |
f9b02bae | 161 | logioctl(dev, com, data, flag) |
c45816fa RC |
162 | caddr_t data; |
163 | { | |
164 | long l; | |
165 | int s; | |
166 | ||
167 | switch (com) { | |
168 | ||
169 | /* return number of characters immediately available */ | |
170 | case FIONREAD: | |
171 | s = splhigh(); | |
9db58063 | 172 | l = msgbufp->msg_bufx - msgbufp->msg_bufr; |
c45816fa RC |
173 | splx(s); |
174 | if (l < 0) | |
175 | l += MSG_BSIZE; | |
176 | *(off_t *)data = l; | |
177 | break; | |
178 | ||
179 | case FIONBIO: | |
c45816fa RC |
180 | break; |
181 | ||
182 | case FIOASYNC: | |
183 | if (*(int *)data) | |
184 | logsoftc.sc_state |= LOG_ASYNC; | |
185 | else | |
186 | logsoftc.sc_state &= ~LOG_ASYNC; | |
187 | break; | |
188 | ||
f9b02bae | 189 | case TIOCSPGRP: |
8fe87cbb | 190 | logsoftc.sc_pgid = *(int *)data; |
c45816fa RC |
191 | break; |
192 | ||
193 | case TIOCGPGRP: | |
f9b02bae | 194 | *(int *)data = logsoftc.sc_pgid; |
c45816fa RC |
195 | break; |
196 | ||
197 | default: | |
18c9b20d | 198 | return (-1); |
c45816fa | 199 | } |
18c9b20d | 200 | return (0); |
c45816fa | 201 | } |