diff options
Diffstat (limited to 'usr/src')
| -rw-r--r-- | usr/src/cmd/mdb/common/modules/libc/libc.c | 45 |
1 files changed, 44 insertions, 1 deletions
diff --git a/usr/src/cmd/mdb/common/modules/libc/libc.c b/usr/src/cmd/mdb/common/modules/libc/libc.c index 4e2aabf061..69f4beda74 100644 --- a/usr/src/cmd/mdb/common/modules/libc/libc.c +++ b/usr/src/cmd/mdb/common/modules/libc/libc.c @@ -22,9 +22,9 @@ /* * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved. * Copyright (c) 2012 by Delphix. All rights reserved. - * Copyright 2017, Joyent, Inc. * Copyright (c) 2019 Carlos Neira <cneirabustos@gmail.com> * Copyright 2019 OmniOS Community Edition (OmniOSce) Association. + * Copyright 2019 Joyent, Inc. */ #include <sys/mdb_modapi.h> @@ -1097,9 +1097,14 @@ tid2ulwp(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv) return (error); } +/* + * This is used by both d_tsd and d_errno, and contains the sum of all + * members used by both commands. + */ typedef struct mdb_libc_ulwp { void *ul_ftsd[TSD_NFAST]; tsd_t *ul_stsd; + int *ul_errnop; } mdb_libc_ulwp_t; /* @@ -1368,7 +1373,45 @@ d_psinfo(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv) return (DCMD_OK); } +static int +d_errno(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv) +{ + mdb_libc_ulwp_t u; + uintptr_t ulwp_addr; + int error, errval; + + if (argc != 0 || (flags & DCMD_ADDRSPEC) == 0) + return (DCMD_USAGE); + + error = tid2ulwp_impl(addr, &ulwp_addr); + if (error != DCMD_OK) + return (error); + + /* + * For historical compatibility, thread 1's errno value is stored in + * a libc global variable 'errno', while each additional thread's + * errno value is stored in ulwp_t->ul_errno. In addition, + * ulwp_t->ul_errnop is set to the address of the thread's errno value, + * (i.e. for tid 1, curthead->ul_errnop = &errno, for tid > 1, + * curthread->ul_errnop = &curthread->ul_errno). + * + * Since errno itself uses *curthread->ul_errnop (see ___errno()) to + * return the thread's current errno value, we do the same. + */ + if (mdb_ctf_vread(&u, "ulwp_t", "mdb_libc_ulwp_t", ulwp_addr, 0) == -1) + return (DCMD_ERR); + + if (mdb_vread(&errval, sizeof (errval), (uintptr_t)u.ul_errnop) == -1) { + mdb_warn("cannot read error value at 0x%p", u.ul_errnop); + return (DCMD_ERR); + } + + mdb_printf("%d\n", errval); + return (DCMD_OK); +} + static const mdb_dcmd_t dcmds[] = { + { "errno", "?", "print errno of a given TID", d_errno, NULL }, { "jmp_buf", ":", "print jmp_buf contents", d_jmp_buf, NULL }, { "sigjmp_buf", ":", "print sigjmp_buf contents", d_sigjmp_buf, NULL }, { "siginfo", ":", "print siginfo_t structure", d_siginfo, NULL }, |