Fix a few initialization style issues

Do not initialise statics and globals to 0, NULL, or false.

Reported by kernel's checkpatch.pl script.

Fix function prototypes with unspecified arguments

Change functions declared as taking unspecified number of arguments
of unspecified type to functions that take no arguments.

Reported by kernel's checkpatch.pl script.

Fix a few sizeof style issues

Reported by kernel's checkpatch.pl script.

Fix a few misspellings in comments

Reported by kernel's checkpatch.pl script.

print_mreq: remove superfluous print_quoted_string calls

The string returned by inet_ntoa(3) has IPv4 dotted-decimal notation,
no need to quote it.

* net.c (print_mreq): Remove print_quoted_string calls.

tests: check decoding of incomplete SCM_TIMESTAMP* control messages

* tests/msg_control.c (test_scm_timestamp, test_scm_timestampns,
test_scm_timestamping): Check decoding of incomplete control messages.

msghdr: print SCM_TIMESTAMP* control messages

Add support for printing control messages containing software and/or
hardware timestamps, which are typically enabled by NTP and PTP
implementations.

* print_timeval.c (print_struct_timeval_data_size): New mpers printer.
* print_timespec.c (print_struct_timespec_data_size,
print_struct_timespec_array_data_size): Likewise.
* msghdr.c (print_scm_timestamp, print_scm_timestampns,
print_scm_timestamping): New functions.
(cmsg_socket_printers): Add them.
* NEWS: Mention this change.
* tests/msg_control.c: Include "xlat.h" and "xlat/scmvals.h".
(test_scm_timestamp, test_scm_timestampns, test_scm_timestamping):
New functions.
(test_sol_socket): Use them.

Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>

tests: check decoding of NETLINK_SOCK_DIAG AF_SMC messages

* tests/netlink_sock_diag.c: Include <linux/smc_diag.h>.
(SMC_ACTIVE): New macro.
(test_smc_diag_req, test_smc_diag_msg): New functions.
(main): Use them.

netlink: add a basic socket diag parser of AF_SMC messages

* linux/smc_diag.h: New file.
* Makefile.am (EXTRA_DIST): Add it.
* netlink_sock_diag.c: Include <linux/smc_diag.h>,
"xlat/smc_diag_extended_flags.h" and "xlat/smc_states.h".
(decode_smc_diag_req, decode_smc_diag_msg): New functions.
(diag_decoders): Add AF_SMC.
* xlat/smc_diag_extended_flags.in: New file.
* xlat/smc_states.in: Likewise.

tests: check decoding of NETLINK_SOCK_DIAG AF_INET messages

* tests/netlink_sock_diag.c: Include <arpa/inet.h>
and <linux/inet_diag.h>.
(test_inet_diag_sockid, test_inet_diag_req, test_inet_diag_req_v2,
test_inet_diag_msg): New functions.
(mian): Use them.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>

netlink: add a basic socket diag parser of AF_INET and AF_INET6 messages

* defs.h (inet_protocols): New xlat prototype.
* linux/inet_diag.h (inet_diag_req): New structure.
(INET_DIAG_*): New enum.
* netlink_sock_diag.c: Include <arpa/inet.h>, <linux/inet_diag.h>
and "xlat/inet_diag_extended_flags.h".
(print_inet_diag_sockid, decode_inet_diag_req_compat)
(decode_inet_diag_req_v2, decode_inet_diag_req)
(decode_inet_diag_msg): New functions.
(diag_decoders): Add AF_INET and AF_INET6;
* xlat/inet_diag_extended_flags.in: New file.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>

Introduce print_inet_addr

* defs.h (print_inet_addr): New prototype.
* sockaddr.c (print_inet_addr): New function.
(print_sockaddr_data_in6): Use it.
* net.c (print_mreq6): Likewise.
* tests/ip_mreq.c (main): Update expected output.

tests: check decoding of NETLINK_SOCK_DIAG AF_PACKET messages

* tests/netlink_sock_diag.c: Include <linux/if_ether.h>
and <linux/packet_diag.h>.
(test_packet_diag_req, test_packet_diag_msg): New functions.
(main): Use them.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>

netlink: add a basic socket diag parser of AF_PACKET messages

* linux/packet_diag.h: New file.
* Makefile.am (EXTRA_DIST): Add it.
* defs.h (ethernet_protocols): New xlat prototype.
* netlink_sock_diag.c: Include <linux/packet_diag.h>
and "xlat/packet_diag_show.h".
(decode_packet_diag_req, decode_packet_diag_msg): New functions.
(diag_decoders): Add AF_PACKET.
* xlat/packet_diag_show.in: New file.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>

tests: check decoding of NETLINK_SOCK_DIAG AF_NETLINK messages

* tests/netlink_sock_diag.c: Include <linux/netlink_diag.h>.
(test_netlink_diag_req, test_netlink_diag_msg): New functions.
(main): Use them.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>

netlink: add a basic socket diag parser of AF_NETLINK messages

* linux/netlink_diag.h (NDIAG_SHOW_GROUPS, NDIAG_SHOW_RING_CFG):
New macros.
* netlink_sock_diag.c: Include <linux/netlink_diag.h>,
"xlat/netlink_diag_show.h" and "xlat/netlink_states.h".
(decode_netlink_diag_req, decode_netlink_diag_msg): New functions.
(diag_decoders): Add AF_NETLINK.
* xlat/netlink_diag_show.in: New file.
* xlat/netlink_states.in: Likewise.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>

tests: check decoding of NETLINK_SOCK_DIAG AF_UNIX messages

* tests/netlink_sock_diag.c: Include <netinet/tcp.h>
and <linux/unix_diag.h>.
(test_odd_family_req, test_odd_family_msg, test_unix_diag_req,
test_unix_diag_msg): New functions.
(main): Use them.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>
Co-authored-by: JingPiao Chen <chenjingpiao@gmail.com>

netlink: add a basic socket diag parser of AF_UNIX messages

* defs.h (socktypes): New xlat prototype.
* linux/unix_diag.h (UDIAG_SHOW_VFS, UDIAG_SHOW_ICONS, UDIAG_SHOW_RQLEN,
UDIAG_SHOW_MEMINFO): New macros.
* netlink_sock_diag.c: Include <sys/socket.h>, <linux/netlink.h>,
<linux/unix_diag.h>, "xlat/tcp_states.h", "xlat/tcp_state_flags.h",
and "xlat/unix_diag_show.h".
(decode_unix_diag_req, decode_unix_diag_msg): New functions.
(netlink_diag_decoder_t): New typedef.
(diag_decoders): New array.
(decode_netlink_sock_diag): Use it.
* xlat/tcp_state_flags.in: New file.
* xlat/tcp_states.in: Likewise.
* xlat/unix_diag_show.in: Likewise.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>
Co-authored-by: JingPiao Chen <chenjingpiao@gmail.com>

netlink: introduce family specific payload decoders

* defs.h (netlink_decoder_t): New typedef.
(DECL_NETLINK): New macro.
(decode_netlink_sock_diag): New prototype.
* netlink.c (netlink_decoders): New array.
(decode_payload): Use it to invoke netlink family specific decoders.
* netlink_sock_diag.c: New file.
* Makefile.am (strace_SOURCES): Add it.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>
Co-authored-by: JingPiao Chen <chenjingpiao@gmail.com>

Update SCM_* constants

* xlat/scmvals.in: Add SCM_TIMESTAMP, SCM_TIMESTAMPNS, SCM_TIMESTAMPING,
SCM_WIFI_STATUS, and SCM_TIMESTAMPING_OPT_STATS.

netlink: refactor decode_nlmsg_type

* netlink.c (decode_nlmsg_type_default, decode_nlmsg_type_netfilter):
New functions.
(nlmsg_types_decoder_t): New typedef.
(nlmsg_types): Add decoder field.
(decode_nlmsg_type): Use it.

tests: extend printstr test

* tests/printstr.c (main): Add a case for short read.

v4l2: fix preprocessor checks

Fix checks for struct v4l2_window.global_alpha and struct
v4l2_sdr_format.buffersize.

* v4l2.c (print_v4l2_format_fmt): Do not assume that
HAVE_STRUCT_V4L2_WINDOW_GLOBAL_ALPHA and
HAVE_STRUCT_V4L2_SDR_FORMAT_BUFFERSIZE are defined.
* tests/ioctl_v4l2.c (init_v4l2_format, dprint_ioctl_v4l2): Likewise.

Move xlat related functions to a separate file

* util.c (xlookup, xlat_bsearch_compare, xlat_search, printxvals,
printxval_searchn, addflags, sprintflags, printflags_ex): Move ...
* xlat.c: ... to this new file.
* Makefile.am (strace_SOURCES): Add it.

socketeutils: extend receive_responses further

This is the second patch in series of implementing NETLINK_GENERIC
protocol decoder.

This change allows passing of opaque user data to the callback function.

* socketutils.c (receive_responses): Change the type of proto_name
argument from "const char *" to "void *" to allow passing
of arbitrary data to the callback function.
Rename proto_name to opaque_data, make it the last argument.
Pass it to the callback function as the last argument.
(inet_parse_response, unix_parse_response, netlink_parse_response):
Change the type of proto_name argument from "const char *" to "void *",
rename it to opaque_data, make it the last argument.
Introduce a local variable proto_name to convert the type
of opaque_data argument from "void *" to "const char *".
(unix_get, inet_get, netlink_get): Cast the protocol name from
"const char *" to "void *" for passing to the callback function.

Signed-off-by: Masatake YAMATO <yamato@redhat.com>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>

socketeutils: extend receive_responses to handle other netlink types

This is the first patch in series of implementing NETLINK_GENERIC
protocol decoder.

receive_responses was written for decoding kernel responses of type
SOCK_DIAG_BY_FAMILY, other types were ignored.

This change makes the type of netlink response a parameter
so the function can be used for other types of communication.

* socketutils.c (receive_responses): add a new parameter
expected_msg_type to handle types other than SOCK_DIAG_BY_FAMILY.

Signed-off-by: Masatake YAMATO <yamato@redhat.com>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>

tests: fix typo

* tests/dup3.c (SKIP_MAIN_UNDEFINED): Remove duplicated &&.

Introduce printflags_ex function

Add printflags_ex extension over printflags64 that, similar
to printxvals, takes a NULL-terminated sequence of xlat pointers.

* defs.h (printflags_ex): New prototype.
(printflags64): Turn into a thin wrapper around printflags_ex.
* netlink.c (decode_nlmsg_flags): Use printflags_ex.
* util.c (printflags_ex): New function.
(printflags64): Remove.
* xlat/netlink_get_flags.in: Remove entries listed
in xlat/netlink_flags.in file.
* xlat/netlink_new_flags.in: Likewise.

tests: add check for decoding netlink get and new flags

* tests/netlink_route.c (test_nlmsg_flags): New function, checks
decoding of NETLINK_ROUTE get and new flags.
(main): Use it.
* tests/netlink_sock_diag.c (test_nlmsg_flags): New function, checks
decoding of NETLINK_SOCK_DIAG get flags.
(main): Use it.
* tests/netlink_xfrm.c: (test_nlmsg_flags): New function, checks
decoding of NETLINK_XFRM get and new flags.
(main): Use it.

netlink: implement generic nlmsg_flags decoding

* netlink.c: Include "xlat/netlink_get_flags.h"
and "xlat/netlink_new_flags.h".
(decode_nlmsg_flags): New function.
(print_nlmsghdr): Use it.
* xlat/netlink_get_flags.in: New file.
* xlat/netlink_new_flags.in: Likewise.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>
Co-authored-by: Dmitry V. Levin <ldv@altlinux.org>

xlat: provide fallback definitions for XFRM_MSG_* constants

Some of XFRM_MSG_* constants were introduced later than the header file
where they are defined.

* xlat/nl_xfrm_types.in: Add default values for constants.

syscall.c: split trace_syscall() into 6 functions

This change removes the trace_syscall function.  Now, the code that uses
syscall.c trace functions is expected to check whether it is a syscall
entry or exit (with entering(tcp)/exiting(tcp)) itself, and then make
an appropriate sequence of function calls.

* defs.h: Update comment on TCB_INSYSCALL.
(trace_syscall): Remove prototype.
(syscall_entering_decode, syscall_entering_trace,
syscall_entering_finish, syscall_exiting_decode, syscall_exiting_trace,
syscall_exiting_finish): New prototypes.
* strace.c (trace_syscall): New static replacement for old trace_syscall.
* syscall.c (trace_syscall): Remove.
(trace_syscall_entering): Split into ...
(syscall_entering_decode, syscall_entering_trace,
syscall_entering_finish): ... new functions.
(trace_syscall_exiting): Split into ...
(syscall_exiting_decode, syscall_exiting_trace,
syscall_exiting_finish): ... new functions.

tests: guard against missing linux/netfilter/nfnetlink.h

nfnetlink was introduced in linux by commit v2.6.14-rc1~1035^2~217,
add a guard for the case when system headers are not fresh enough.

* configure.ac (AC_CHECK_HEADERS): Add linux/netfilter/nfnetlink.h.
* tests/netlink_netfilter.c: Check for HAVE_LINUX_NETFILTER_NFNETLINK_H.

tests: check decoding of NETLINK_XFRM message types

* tests/netlink_xfrm.c: New file.
* tests/gen_tests.in (netlink_xfrm): New entry.
* tests/pure_executables.list: Add netlink_xfrm.
* tests/.gitignore: Likewise.

tests: check decoding of NETLINK_SELINUX message types

* tests/netlink_selinux.c: New file.
* tests/gen_tests.in (netlink_selinux): New entry.
* tests/pure_executables.list: Add netlink_selinux.
* tests/.gitignore: Likewise.

tests: check decoding of NETLINK_NETFILTER message types

* tests/netlink_netfilter.c: New file.
* tests/gen_tests.in (netlink_netfilter): New entry.
* tests/pure_executables.list: Add netlink_netfilter.
* tests/.gitignore: Likewise.

tests: check decoding of NETLINK_AUDIT message types

* tests/netlink_audit.c: New file.
* tests/gen_tests.in (netlink_audit): New entry.
* tests/pure_executables.list: Add netlink_audit.
* tests/.gitignore: Likewise.

tests: check decoding of NETLINK_ROUTE message types

* tests/netlink_route.c: New file.
* tests/gen_tests.in (netlink_route): New entry.
* tests/pure_executables.list: Add netlink_route.
* tests/.gitignore: Likewise.

tests: check decoding of NETLINK_SOCK_DIAG message types

* tests/netlink_sock_diag.c: New file.
* tests/netlink_sock_diag.test: New test.
* tests/pure_executables.list: Add netlink_sock_diag.
* tests/.gitignore: Likewise.
* tests/Makefile.am (DECODER_TESTS): Add netlink_sock_diag.test.

tests: use create_nl_socket in netlink_protocol.test

* tests/netlink_protocol.c (main): Use create_nl_socket.

tests: change netlink_protocol.test to trace sendto syscalls only

* tests/gen_tests.in (netlink_protocol): Replace %network with sendto.
* tests/netlink_protocol.c (main): Update expected output.

tests: enhance create_nl_socket diagnostics messages

* tests/tests.h (create_nl_socket): Rename to create_nl_socket_ext,
add a string argument.
(create_nl_socket): New macro wrapper around create_nl_socket_ext.
* tests/create_nl_socket.c (create_nl_socket): Rename
to create_nl_socket_ext, add a string argument, include it
in diagnostic messages.

tests: use const and designated initializers in create_nl_socket.c

* tests/create_nl_socket.c: Stop including <string.h>.
(create_nl_socket): Use const and designated initializers.

tests: add create_nl_socket function to libtests

* tests/create_nl_socket.c: New file.
* tests/tests.h (create_nl_socket): New prototype.
* tests/Makefile.am (libtests_a_SOURCES): Add create_nl_socket.c.

netlink: add decoding of NETLINK_NETFILTER message types

* xlat/nl_netfilter_msg_types.in: New file.
* xlat/nl_netfilter_subsys_ids.in: Likewise.
* netlink.c: Include "xlat/nl_netfilter_msg_types.h"
and "xlat/nl_netfilter_subsys_ids.h".
(nlmsg_types): Add NETLINK_NETFILTER.
(decode_nlmsg_type): Handle NETLINK_NETFILTER.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>

netlink: add decoding of NETLINK_XFRM message types

* xlat/nl_xfrm_types.in: New file.
* netlink.c: Include "xlat/nl_xfrm_types.h".
(nlmsg_types): Add NETLINK_XFRM.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>

netlink: add decoding of NETLINK_SELINUX message types

* xlat/nl_selinux_types.in: New file.
* netlink.c: Include "xlat/nl_selinux_types.h".
(nlmsg_types): Add NETLINK_SELINUX.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>

netlink: add decoding of NETLINK_ROUTE message types

* xlat/nl_route_types.in: New file.
* netlink.c: Include <linux/rtnetlink.h> and "xlat/nl_route_types.h".
(nlmsg_types): Add NETLINK_ROUTE.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>

netlink: add decoding of NETLINK_AUDIT message types

* xlat/nl_audit_types.in: New file.
* netlink.c: Include <linux/audit.h> and "xlat/nl_audit_types.h".
(nlmsg_types): Add NETLINK_AUDIT.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>

netlink: implement generic nlmsg_type decoding

Implement a pluggable mechanism of nlmsg_type decoding.
Add decoding of NETLINK_SOCK_DIAG types.

* linux/sock_diag.h (SOCK_DESTROY): New macro.
* xlat/nl_sock_diag_types.in: New file.
* netlink.c: Include xlat/nl_sock_diag_types.h.
(get_fd_nl_family, decode_nlmsg_type): New functions.
(print_nlmsghdr): Use them for nlmsg_type decoding.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>

netlink: add netlink family argument to printers and decoders

* netlink.c (NL_FAMILY_ERROR, NL_FAMILY_DEFAULT): New constants.
(print_nlmsghdr): Add netlink family argument, change return type
to int, return family.
(decode_nlmsghdr_with_payload, decode_nlmsgerr, decode_payload): Add
netlink family argument.  All callers updated.

Add file descriptor argument to decode_netlink

* defs.h (decode_netlink): Add file descriptor argument.
* io.c (print_iovec): Specify file descriptor to decode_netlink.
* net.c (decode_sockbuf): Likewise.
* netlink.c (print_nlmsghdr, decode_nlmsghdr_with_payload,
decode_nlmsgerr, decode_payload, decode_nlmsghdr_with_payload,
decode_netlink): Likewise.
All callers updated.

Co-authored-by: Dmitry V. Levin <ldv@altlinux.org>

Introduce getfdinode to obtain inode from fd

* defs.h (getfdinode): New prototype.
* utils.c (getfdinode): New function.

Co-authored-by: Dmitry V. Levin <ldv@altlinux.org>

Introduce get_sockaddr_by_inode

Add a way to get socket information without printing it.

* defs.h (get_sockaddr_by_inode): New prototype.
* socketutils.c (get_sockaddr_by_inode): New function.

Co-authored-by: Dmitry V. Levin <ldv@altlinux.org>

socketutils.c: introduce get_sockaddr_by_inode_uncached

* socketutils.c (get_sockaddr_by_inode_uncached): New function.
(print_sockaddr_by_inode_uncached): Use it.

socketutils.c: use get_sockaddr_by_inode_cached

* socketutils.c (unix_print, inet_print, tcp_v4_print, tcp_v6_print,
udp_v4_print, udp_v6_print, netlink_print): Remove.
(unix_get, inet_get, tcp_v4_get, tcp_v6_get, udp_v4_get,
udp_v6_get, netlink_get): New functions.
(protocols): Update.

Co-authored-by: Dmitry V. Levin <ldv@altlinux.org>

socketutils.c: move inet_print closer to its first use

* socketutils.c (inet_print): Move right before tcp_v4_print.

socketutils.c: introduce cache_inode_details

cache_inode_details gives a way to obtain cache information without
printing it.

* socketutils.c (cache_and_print_inode_details): Rename
to cache_inode_details.  Do not print cached information.
(inet_parse_response, unix_parse_response, netlink_parse_response):
Use cache_inode_details instead of cache_and_print_inode_details.
(inet_print, unix_print, netlink_print): Call
print_sockaddr_by_inode_cached.

Co-authored-by: Dmitry V. Levin <ldv@altlinux.org>

strace.c: move termination code to a separate function

This will be needed for the pull-style API.

* strace.c (terminate): New function.
(main): Use it.

tests: avoid hitting SO_SNDBUF limit in sendfile/sendfile64 tests

Do not assume that an executable is small enough and SO_SNDBUF is large
enough so that the executable could be sendfile'ed into a socket pair.

* tests/sendfile.c (main): Create a regular file of the right size
to avoid hitting SO_SNDBUF limit.
* tests/sendfile64.c: Likewise.

Reported-by: Andreas Schwab <schwab@linux-m68k.org>

Move netlink_protocols definition from net.c to netlink.c

The side effect of #include "xlat/netlink_protocols.h" is
NETLINK_* constants properly defined in that header file.
While net.c does not use these constants itself, netlink.c
is going to need them soon.

* net.c: Move inclusion of "xlat/netlink_protocols.h" ...
* netlink.c: ... here.

travis: switch from gcc-6 to gcc-7

* .travis.yml (matrix): Change gcc-6 to gcc-7.

tests: extend checking of NLMSG_DONE decoding

* tests/netlink_protocol.c (test_nlmsg_done):  Use designated
initializers.  Check decoding of messages with non-integer payload.

netlink: decode NLMSG_DONE messages

* netlink.c (decode_payload): Decode NLMSG_DONE messages.
* tests/netlink_protocol.c (test_nlmsg_done): New function
for checking decoding of NLMSG_DONE messages.
(main): Use it.

socketutils.c: introduce get_sockaddr_by_inode_cached

* socketutils.c (get_sockaddr_by_inode_cached): New function.
(print_sockaddr_by_inode_cached): Use it.

Unexport print_sockaddr_by_inode_cached

Change print_sockaddr_by_inode to be the only function exposed,
hide print_sockaddr_by_inode_cached as a part of implementation.

* defs.h (print_sockaddr_by_inode_cached): Remove prototype.
(print_sockaddr_by_inode): Add struct tcb * and descriptor arguments.
* socketutils.c (print_sockaddr_by_inode_cached): Make static.
(print_sockaddr_by_inode): Rename to print_sockaddr_by_inode_uncached,
make static.
(print_sockaddr_by_inode): New function.
* util.c (printfd): Update to use new print_sockaddr_by_inode.

Introduce str_strip_prefix_len function and STR_STRIP_PREFIX macro

Address proliferation of string prefix check implementations.

* defs.h (str_strip_prefix_len): New inline function.
(STR_STRIP_PREFIX): New macro.
* qualify.c (strip_prefix): Remove.
(parse_inject_token): Use STR_STRIP_PREFIX instead of strip_prefix.
(qualify): Use str_strip_prefix_len.
* socketutils.c (netlink_parse_response): Likewise.
* util.c (printfd): Likewise.

netlink: move NLMSG_ERROR payload length check to nlmsgerr decoder

Move decoder specific check to the decoder.

* netlink.c (decode_payload): Move NLMSG_ERROR payload length check ...
(decode_nlmsgerr): ... here.

strace.c: handle PTRACE_EVENT_EXEC like other events

There is nothing unusual about PTRACE_EVENT_EXEC that would require
a special treatment.

* strace.c (next_event): Move PTRACE_EVENT_EXEC handling to the main
switch statement.

strace.c: remove dead code

As strace does not use WCONTINUED flag, there is no need to handle
WIFCONTINUED status.

* strace.c (print_debug_info) [WIFCONTINUED]: Remove.
(next_event): Remove redundant !WIFSTOPPED check.

strace.c: refactor trace into two functions

This change decouples waiting for next event from reacting to it.  This
makes the control flow easier to understand, and serves as a preparation
for implementing a pull-style API for LuaJIT.

* strace.c (enum trace_event): New enum.
(trace): Split into ...
(next_event, dispatch_event): ... new functions.
(main): Use them.

scno.am: include config.h before syscallent.h

This fixes generation of syscallent.i and subsequent scno.h files
on mips where syscallent.h checks macros defined in config.h.

* scno.am (syscallent.i): Add $(top_builddir)/config.h
to prerequisites, include it.
* NEWS: Mention this fix.

Reported-by: David Robins <dbrobins@i4031.net>

tests: check decoding of sigaction syscall

* tests/sigaction.c: New file.
* tests/gen_tests.in (sigaction): New entry.
* tests/pure_executables.list: Add sigaction.
* tests/.gitignore: Likewise.

tests: rename sigaction.test to rt_sigaction.test

* tests/sigaction.awk: Rename to rt_sigaction.awk.
* tests/sigaction.c: Rename to tests/rt_sigaction.c.
* tests/sigaction.test: Rename to tests/rt_sigaction.test.
* tests/.gitignore: Replace sigaction with rt_sigaction.
* tests/pure_executables.list: Likewise.
* tests/Makefile.am (DECODER_TESTS): Replace sigaction.test
with rt_sigaction.test.
(EXTRA_DIST): Replace sigaction.awk with rt_sigaction.awk.

sparc: enhance decoding of signal number argument of sigaction syscall

On sparc, unlike all other architectures, old sigaction syscall takes
a negated signal number.

* signal.c (SYS_FUNC(sigaction)) [SPARC || SPARC64]: Enhance printing
of negative signal number argument.

signal: enhance printing of old_sigaction.mask

* signal.c (decode_old_sigaction): Print old_sigaction.mask
using tprint_old_sigmask_val.

signal: limit scope of struct old_sigaction32 definition

* signal.c (struct old_sigaction32): Define only if [!current_wordsize].

signal: fix decoding of struct old_sigaction on some architectures

On alpha, struct old_sigaction.sa_flags has a 32-bit type.

On mips, only first word of old_sigaction.sa_mask is read.

On all architectures except alpha and mips that have old sigaction
syscall, struct old_sigaction has sa_restorer field that has to be
decoded.

* signal.c (struct old_sigaction) [ALPHA]: Change sa_flags type
to unsigned int, add ATTRIBUTE_PACKED.
[MIPS]: Dhrink sa_mask array to 1 element.
[!ALPHA && !MIPS]: Define sa_restorer field unconditionally.
(struct old_sigaction32): Likewise.
(decode_old_sigaction) [!current_wordsize]: Initialize sa_restorer field
from old_sigaction32.sa_restorer unconditionally.
[!ALPHA && !MIPS]: Print old_sigaction.sa_restorer if SA_RESTORER flag
is set.
* NEWS: Mention this change.

xlat: rename SA_STACK to SA_ONSTACK

SA_ONSTACK is the standard name while its alias SA_STACK is not even
defined on many platforms.

* xlat/sigact_flags.in (SA_STACK): Rename to SA_ONSTACK.

tests: check decoding of sigpending syscall

* tests/sigpending.c: New file.
* tests/gen_tests.in (sigpending): New entry.
* tests/pure_executables.list: Add sigpending.
* tests/.gitignore: Likewise.

tests: check decoding of sigprocmask syscall

* tests/sigprocmask.c: New file.
* tests/gen_tests.in (sigprocmask): New entry.
* tests/pure_executables.list: Add sigprocmask.
* tests/.gitignore: Likewise.

alpha: rename sys_sigprocmask to sys_osf_sigprocmask

Parsers of sigprocmask and osf_sigprocmask syscalls are different
anyway, so rename the function to match the syscall name.

* signal.c [ALPHA] (SYS_FUNC(sigprocmask)): Rename
to SYS_FUNC(osf_sigprocmask).
* linux/alpha/syscallent.h: Update sys_func.

Enable coverage when strace is self terminated by signal

The data collected by -fprofile-arcs during program run is saved
on program exit.  When program is terminated by signal, the data
is not saved.  However, libgcov provides an interface to dump
the data at runtime.

* m4/ax_code_coverage.m4 (AX_CODE_COVERAGE): Add -DENABLE_COVERAGE_GCOV
to CODE_COVERAGE_CPPFLAGS.
* strace.c [ENABLE_COVERAGE_GCOV] (__gcov_flush): New prototype.
(main) [ENABLE_COVERAGE_GCOV]: Call __gcov_flush() before raise()
and sigprocmask() calls that might cause program termination.

tests: check termination signal forwarding

* tests/run_expect_termsig.c: New file.
* tests/unblock_reset_raise.c: Likewise.
* tests/termsig.test: New test.
* tests/.gitignore: Add run_expect_termsig and unblock_reset_raise.
* tests/Makefile.am (check_PROGRAMS): Likewise.
(MISC_TESTS): Add termsig.test.

Fix termination signal forwarding

When traced command is terminated by a blocked signal, unblock
that signal to ensure strace termination with the same signal.

* strace.c (main): Unblock the signal raised for strace termination.
* NEWS: Mention this change.

Do not reset SIGCHLD handler in tracees to SIG_DFL

While strace resets SIGCHLD handler to the default action so that
waitpid definitely works without losing track of children, tracees
should not inherit this change.

* strace.c (struct exec_params): Add child_sa field.
(init): When setting SIGCHLD handler to SIG_DFL, save the old handler.
(exec_or_die): Restore SIGCHLD handler if it was different from SIG_DFL
at startup.
* NEWS: Mention this change.

Refactor setting of signal handlers to reduce redundancy

* strace.c (set_sigaction): New function.
(init): Use it instead of sigaction with sigaddset.

tests: check how signals are unblocked in interactive mode

* tests/block_reset_raise_run.c: New file.
* tests/interactive_block.test: New test.
* tests/.gitignore: Add block_reset_raise_run.
* tests/Makefile.am (check_PROGRAMS): Likewise.
(MISC_TESTS): Add interactive_block.test.

Fix unblocking of signals in interactive mode

In interactive mode (-I2), those signals that were blocked at startup
will remain blocked for the whole period of strace execution.

* strace.c (empty_set): Rename to start_set.  All users changed.
(init): Initialize start_set and blocked_set to the set of currently
blocked signals.
(startup_attach, trace): Use SIG_SETMASK instead of SIG_BLOCK.
* NEWS: Mention this change.

Cleanup interactive check

* strace.c (init): Check for INTR_WHILE_WAIT mode the same way
as in other places.

tests: check decoding of signal syscall

* tests/signal.c: New file.
* tests/gen_tests.in (signal): New entry.
* tests/pure_executables.list: Add signal.
* tests/.gitignore: Likewise.

Unify capitalisation of (c) in copyright notices

Post-release administrivia

* NEWS: Add a header line for the next release.
* debian/changelog.in: Add a changelog entry for 4.17-1.
* strace.spec.in: Likewise.

Prepare for 4.17 release

* NEWS: Update for 4.17 release.

powerpc64, sparc, sparc64: wire up statx syscall

* linux/powerpc64/syscallent.h [383]: Add statx entry.
* linux/sparc/syscallent.h [360]: Likewise.
* linux/sparc64/syscallent.h [360]: Likewise.

Fix compat personality support for sgetmask syscall

* signal.c (SYS_FUNC(sgetmask)): Replace sprintsigmask_val
with sprint_old_sigmask_val.
* tests/sxetmask.c (main): Check decoding of signal mask containing
RT signals.

Fix decoding of sgetmask and ssetmask syscalls

Old ssetmask syscall takes an argument and returns a value of type int.
Old sgetmask syscall may return an error.

* signal.c (SYS_FUNC(ssetmask)): Explicitly convert the argument
and return value to unsigned int, print it using sprint_old_sigmask_val.
(SYS_FUNC(sgetmask)): Do not print the mask in case of syserror.
* tests/sxetmask.c: New file.
* tests/gen_tests.in (sxetmask): New entry.
* tests/pure_executables.list: Add sxetmask.
* tests/.gitignore: Likewise.
* NEWS: Mention this fix.

Add copyright headers

Add scripts for automating copyright notices update

* maint/update_copyright_years.awk: New file.
* maint/update_copyright_years.sh: Likewise.

Co-authored-by: Elvira Khabirova <lineprinter0@gmail.com>

Fix typos in copyright notices