diff --git a/sbin/sysctl/sysctl.8 b/sbin/sysctl/sysctl.8 index f6c1bb9e730..ec2e0540acb 100644 --- a/sbin/sysctl/sysctl.8 +++ b/sbin/sysctl/sysctl.8 @@ -44,7 +44,7 @@ .Ar name Ns Op = Ns Ar value .Ar ... .Nm -.Op Fl beNnox +.Op Fl bdeNnox .Fl a .Sh DESCRIPTION The @@ -71,6 +71,8 @@ the command line. Force the value of the variable(s) to be output in raw, binary format. No names are printed and no terminating newlines are output. This is mostly useful with a single variable. +.It Fl d +Print the description of the variable instead of its value. .It Fl e Separate the name and the value of the variable(s) with .Ql = . diff --git a/sbin/sysctl/sysctl.c b/sbin/sysctl/sysctl.c index 5ffb810a4b5..eb30b6e0303 100644 --- a/sbin/sysctl/sysctl.c +++ b/sbin/sysctl/sysctl.c @@ -58,7 +58,7 @@ static const char rcsid[] = #include #include -static int aflag, bflag, eflag, Nflag, nflag, oflag, xflag; +static int aflag, bflag, dflag, eflag, Nflag, nflag, oflag, xflag; static int oidfmt(int *, int, char *, u_int *); static void parse(char *); @@ -71,8 +71,8 @@ usage(void) { (void)fprintf(stderr, "%s\n%s\n", - "usage: sysctl [-beNnox] variable[=value] ...", - " sysctl [-beNnox] -a"); + "usage: sysctl [-bdeNnox] variable[=value] ...", + " sysctl [-bdeNnox] -a"); exit(1); } @@ -83,7 +83,7 @@ main(int argc, char **argv) setbuf(stdout,0); setbuf(stderr,0); - while ((ch = getopt(argc, argv, "AabeNnowxX")) != -1) { + while ((ch = getopt(argc, argv, "AabdeNnowxX")) != -1) { switch (ch) { case 'A': /* compatibility */ @@ -95,6 +95,9 @@ main(int argc, char **argv) case 'b': bflag = 1; break; + case 'd': + dflag = 1; + break; case 'e': eflag = 1; break; @@ -409,6 +412,15 @@ show_var(int *oid, int nlen) else sep = ": "; + if (dflag) { /* just print description */ + qoid[1] = 5; + j = sizeof(buf); + i = sysctl(qoid, nlen + 2, buf, &j, 0, 0); + if (!nflag) + printf("%s%s", name, sep); + printf("%s", buf); + return (0); + } /* find an estimate of how much we need for this var */ j = 0; i = sysctl(oid, nlen, 0, &j, 0, 0); diff --git a/sys/kern/kern_sysctl.c b/sys/kern/kern_sysctl.c index 94e4a725a5e..39decc7d78e 100644 --- a/sys/kern/kern_sysctl.c +++ b/sys/kern/kern_sysctl.c @@ -310,6 +310,8 @@ sysctl_remove_oid(struct sysctl_oid *oidp, int del, int recurse) } sysctl_unregister_oid(oidp); if (del) { + if (oidp->descr) + free(oidp->descr, M_SYSCTLOID); free((void *)(uintptr_t)(const void *)oidp->oid_name, M_SYSCTLOID); free(oidp, M_SYSCTLOID); @@ -370,6 +372,12 @@ sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent, oidp->oid_arg2 = arg2; } oidp->oid_fmt = fmt; + if (descr) { + int len = strlen(descr) + 1; + oidp->descr = malloc(len, M_SYSCTLOID, M_WAITOK); + if (oidp->descr) + strcpy(oidp->descr, descr); + } /* Update the context, if used */ if (clist != NULL) sysctl_ctx_entry_add(clist, oidp); @@ -409,6 +417,7 @@ SYSINIT(sysctl, SI_SUB_KMEM, SI_ORDER_ANY, sysctl_register_all, 0); * {0,2,...} return the next OID. * {0,3} return the OID of the name in "new" * {0,4,...} return the kind & format info for the "..." OID. + * {0,5,...} return the description the "..." OID. */ static void @@ -708,6 +717,24 @@ sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS) SYSCTL_NODE(_sysctl, 4, oidfmt, CTLFLAG_RD, sysctl_sysctl_oidfmt, ""); +static int +sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS) +{ + struct sysctl_oid *oid; + int error; + + error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); + if (error) + return (error); + + if (!oid->descr) + return (ENOENT); + error = SYSCTL_OUT(req, oid->descr, strlen(oid->descr) + 1); + return (error); +} + +SYSCTL_NODE(_sysctl, 5, oiddescr, CTLFLAG_RD, sysctl_sysctl_oiddescr, ""); + /* * Default "handler" functions. */ diff --git a/sys/sys/sysctl.h b/sys/sys/sysctl.h index 71440572c56..422889faa9c 100644 --- a/sys/sys/sysctl.h +++ b/sys/sys/sysctl.h @@ -140,6 +140,7 @@ struct sysctl_oid { int (*oid_handler)(SYSCTL_HANDLER_ARGS); const char *oid_fmt; int oid_refcnt; + char *descr; }; #define SYSCTL_IN(r, p, l) (r->newfunc)(r, p, l) @@ -181,7 +182,7 @@ TAILQ_HEAD(sysctl_ctx_list, sysctl_ctx_entry); #define SYSCTL_OID(parent, nbr, name, kind, a1, a2, handler, fmt, descr) \ static struct sysctl_oid sysctl__##parent##_##name = { \ &sysctl_##parent##_children, { 0 }, \ - nbr, kind, a1, a2, #name, handler, fmt, 0 }; \ + nbr, kind, a1, a2, #name, handler, fmt, 0, descr }; \ DATA_SET(sysctl_set, sysctl__##parent##_##name); #define SYSCTL_ADD_OID(ctx, parent, nbr, name, kind, a1, a2, handler, fmt, descr) \