truss: decode sysctl names.

Submitted by:	Pawel Biernacki
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D21688

diff --git a/usr.bin/truss/syscall.h b/usr.bin/truss/syscall.h
index 3ac2c1b7f4acbf7da12fe201419dd144964cae3d..74fbcb7b254512f3bad093e97908e869896d3198 100644 (file)
--- a/usr.bin/truss/syscall.h
+++ b/usr.bin/truss/syscall.h
@@ -131,6 +131,7 @@ enum Argtype {
        Sockprotocol,
        Socktype,
        Sysarch,
+       Sysctl,
        Umtxop,
        Waitoptions,
        Whence,

diff --git a/usr.bin/truss/syscalls.c b/usr.bin/truss/syscalls.c
index 9b883ff558a9e5ac4e03697fd55cb34f036c0bb5..e6a1fbd21bf8bd969561a2be2b28676f2a35303e 100644 (file)
--- a/usr.bin/truss/syscalls.c
+++ b/usr.bin/truss/syscalls.c
@@ -51,6 +51,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/socket.h>
 #define _WANT_FREEBSD11_STAT
 #include <sys/stat.h>
+#include <sys/sysctl.h>
 #include <sys/time.h>
 #include <sys/un.h>
 #include <sys/wait.h>
@@ -506,6 +507,12 @@ static struct syscall decoded_syscalls[] = {
          .args = { { Name, 0 }, { Atfd, 1 }, { Name, 2 } } },
        { .name = "sysarch", .ret_type = 1, .nargs = 2,
          .args = { { Sysarch, 0 }, { Ptr, 1 } } },
+       { .name = "__sysctl", .ret_type = 1, .nargs = 6,
+         .args = { { Sysctl, 0 }, { Sizet, 1 }, { Ptr, 2 }, { Ptr, 3 },
+                   { Ptr, 4 }, { Sizet, 5 } } },
+       { .name = "__sysctlbyname", .ret_type = 1, .nargs = 6,
+         .args = { { Name, 0 }, { Sizet, 1 }, { Ptr, 2 }, { Ptr, 3 },
+                   { Ptr, 4}, { Sizet, 5 } } },
        { .name = "thr_kill", .ret_type = 1, .nargs = 2,
          .args = { { Long, 0 }, { Signal, 1 } } },
        { .name = "thr_self", .ret_type = 1, .nargs = 1,
@@ -1551,6 +1558,15 @@ print_cmsgs(FILE *fp, pid_t pid, bool receive, struct msghdr *msghdr)
        free(cmsgbuf);
 }
 
+static void
+print_sysctl_oid(FILE *fp, int *oid, int len)
+{
+       int i;
+
+       for (i = 0; i < len; i++)
+               fprintf(fp, ".%d", oid[i]);
+}
+
 /*
  * Converts a syscall argument into a string.  Said string is
  * allocated via malloc(), so needs to be free()'d.  sc is
@@ -2267,6 +2283,62 @@ print_arg(struct syscall_args *sc, unsigned long *args, register_t *retval,
                print_integer_arg(sysdecode_sysarch_number, fp,
                    args[sc->offset]);
                break;
+       case Sysctl: {
+               char name[BUFSIZ];
+               int oid[CTL_MAXNAME + 2], qoid[CTL_MAXNAME + 2];
+               size_t i;
+               int len;
+
+               memset(name, 0, sizeof(name));
+               len = args[sc->offset + 1];
+               if (get_struct(pid, (void *)args[sc->offset], oid,
+                   len * sizeof(oid[0])) != -1) {
+                       fprintf(fp, "\"");
+                       if (oid[0] == CTL_SYSCTL) {
+                               fprintf(fp, "sysctl.");
+                               switch (oid[1]) {
+                               case CTL_SYSCTL_DEBUG:
+                                       fprintf(fp, "debug");
+                                       break;
+                               case CTL_SYSCTL_NAME:
+                                       fprintf(fp, "name");
+                                       print_sysctl_oid(fp, oid + 2, len - 2);
+                                       break;
+                               case CTL_SYSCTL_NEXT:
+                                       fprintf(fp, "next");
+                                       break;
+                               case CTL_SYSCTL_NAME2OID:
+                                       fprintf(fp, "name2oid");
+                                       break;
+                               case CTL_SYSCTL_OIDFMT:
+                                       fprintf(fp, "oidfmt");
+                                       print_sysctl_oid(fp, oid + 2, len - 2);
+                                       break;
+                               case CTL_SYSCTL_OIDDESCR:
+                                       fprintf(fp, "oiddescr");
+                                       print_sysctl_oid(fp, oid + 2, len - 2);
+                                       break;
+                               case CTL_SYSCTL_OIDLABEL:
+                                       fprintf(fp, "oidlabel");
+                                       print_sysctl_oid(fp, oid + 2, len - 2);
+                                       break;
+                               default:
+                                       print_sysctl_oid(fp, oid + 1, len - 1);
+                               }
+                       } else {
+                               qoid[0] = CTL_SYSCTL;
+                               qoid[1] = CTL_SYSCTL_NAME;
+                               memcpy(qoid + 2, oid, len * sizeof(int));
+                               i = sizeof(name);
+                               if (sysctl(qoid, len + 2, name, &i, 0, 0) == -1)
+                                       print_sysctl_oid(fp, qoid + 2, len);
+                               else
+                                       fprintf(fp, "%s", name);
+                       }
+                       fprintf(fp, "\"");
+               }
+               break;
+       }
        case PipeFds:
                /*
                 * The pipe() system call in the kernel returns its