projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 42ddb7eb BJ |
1 | /* |
| 2 | * Suck up system messages | |
| 3 | * dmesg | |
| 4 | * print current buffer | |
| 5 | * dmesg - | |
| 6 | * print and update incremental history | |
| 7 | */ | |
| 8 | ||
| 9 | #include <stdio.h> | |
| 10 | #include <sys/param.h> | |
| 11 | #include <a.out.h> | |
| 12 | #include <signal.h> | |
| 13 | ||
| 14 | char msgbuf[MSGBUFS]; | |
| 15 | char *msgbufp; | |
| 16 | int sflg; | |
| 17 | int of = -1; | |
| 18 | ||
| 19 | struct { | |
| 20 | char *omsgflg; | |
| 21 | int omindex; | |
| 22 | char omsgbuf[MSGBUFS]; | |
| 23 | } omesg; | |
| 24 | struct nlist nl[3] = { | |
| 25 | {"_msgbuf"}, | |
| 26 | {"_msgbufp"} | |
| 27 | }; | |
| 28 | ||
| 29 | main(argc, argv) | |
| 30 | char **argv; | |
| 31 | { | |
| 32 | int mem; | |
| 33 | register char *mp, *omp, *mstart; | |
| 34 | int timeout(); | |
| 35 | int samef; | |
| 36 | ||
| 37 | signal(SIGALRM, timeout); | |
| 38 | alarm(30); | |
| 39 | if (argc>1 && argv[1][0] == '-') { | |
| 40 | sflg++; | |
| 41 | argc--; | |
| 42 | argv++; | |
| 43 | } | |
| 44 | if (sflg) | |
| 45 | of = open("/usr/adm/msgbuf", 2); | |
| 46 | read(of, (char *)&omesg, sizeof(omesg)); | |
| 47 | lseek(of, 0L, 0); | |
| 48 | sflg = 0; | |
| 49 | nlist(argc>2? argv[2]:"/vmunix", nl); | |
| 50 | if (nl[0].n_type==0) | |
| 51 | done("No namelist\n"); | |
| 52 | if ((mem = open((argc>1? argv[1]: "/dev/kmem"), 0)) < 0) | |
| 53 | done("No mem\n"); | |
| 54 | lseek(mem, (long)nl[0].n_value, 0); | |
| 55 | read(mem, msgbuf, MSGBUFS); | |
| 56 | lseek(mem, (long)nl[1].n_value, 0); | |
| 57 | read(mem, (char *)&msgbufp, sizeof(msgbufp)); | |
| 58 | if (msgbufp < (char *)nl[0].n_value || msgbufp >= (char *)nl[0].n_value+MSGBUFS) | |
| 59 | done("Namelist mismatch\n"); | |
| 60 | msgbufp += msgbuf - (char *)nl[0].n_value; | |
| 61 | mstart = &msgbuf[omesg.omindex]; | |
| 62 | omp = &omesg.omsgbuf[msgbufp-msgbuf]; | |
| 63 | mp = msgbufp; | |
| 64 | samef = 1; | |
| 65 | do { | |
| 66 | if (*mp++ != *omp++) { | |
| 67 | mstart = msgbufp; | |
| 68 | samef = 0; | |
| 69 | pdate(); | |
| 70 | printf("...\n"); | |
| 71 | break; | |
| 72 | } | |
| 73 | if (mp == &msgbuf[MSGBUFS]) | |
| 74 | mp = msgbuf; | |
| 75 | if (omp == &omesg.omsgbuf[MSGBUFS]) | |
| 76 | omp = omesg.omsgbuf; | |
| 77 | } while (mp != mstart); | |
| 78 | if (samef && mstart == msgbufp) | |
| 79 | exit(0); | |
| 80 | mp = mstart; | |
| 81 | do { | |
| 82 | pdate(); | |
| 83 | if (*mp) | |
| 84 | putchar(*mp); | |
| 85 | mp++; | |
| 86 | if (mp == &msgbuf[MSGBUFS]) | |
| 87 | mp = msgbuf; | |
| 88 | } while (mp != msgbufp); | |
| 89 | done((char *)NULL); | |
| 90 | } | |
| 91 | ||
| 92 | done(s) | |
| 93 | char *s; | |
| 94 | { | |
| 95 | register char *p, *q; | |
| 96 | ||
| 97 | if (s && s!=omesg.omsgflg && sflg==0) { | |
| 98 | pdate(); | |
| 99 | printf(s); | |
| 100 | } | |
| 101 | omesg.omsgflg = s; | |
| 102 | q = omesg.omsgbuf; | |
| 103 | for (p = msgbuf; p < &msgbuf[MSGBUFS]; ) | |
| 104 | *q++ = *p++; | |
| 105 | omesg.omindex = msgbufp - msgbuf; | |
| 106 | write(of, (char *)&omesg, sizeof(omesg)); | |
| 107 | exit(s!=NULL); | |
| 108 | } | |
| 109 | ||
| 110 | pdate() | |
| 111 | { | |
| 112 | extern char *ctime(); | |
| 113 | static firstime; | |
| 114 | time_t tbuf; | |
| 115 | ||
| 116 | if (firstime==0) { | |
| 117 | firstime++; | |
| 118 | time(&tbuf); | |
| 119 | printf("\n%.12s\n", ctime(&tbuf)+4); | |
| 120 | } | |
| 121 | } | |
| 122 | ||
| 123 | timeout() | |
| 124 | { | |
| 125 | done("Buffer file screwed up\n"); | |
| 126 | } |