# BST-TIMEOUT: 600   # 191 cases but only ~32 process spawns -- the probe, one
#                    # awk for all 110 scored values, 22 archive greps and a
#                    # handful of cats. Bound taken from 79-libtirpc (~45 spawns,
#                    # 600) rather than from a measurement of this suite, which
#                    # did not exist when it was first written; re-set it from
#                    # the ==BST-SUITE line once there is one.
. "$BST_LIB"

# liburcu (userspace-rcu 0.14.2, poky recipes-support/liburcu) is the userspace
# read-copy-update library: an RCU read side and grace period in four flavors,
# the uatomic/barrier abstraction under them, and the lock-free concurrent data
# structures built on top -- rculfhash, wfcqueue, wfstack, lfstack, rculfqueue.
# It is the synchronisation substrate lttng-tools is built on.
#
# The distro is static-only, so what the image gets is eight archives under
# /usr/lib, ~90 headers under /usr/include/urcu, seven .pc files -- and NOT ONE
# EXECUTABLE. Nothing in this package is reachable from a shell, so a suite made
# only of file tests could assert that liburcu.a exists, which would pass just
# as happily if every function in the archive trapped on first call. That is why
# the second half of this file drives /usr/libexec/liburcu-tests/liburcu-probe,
# which the recipe cross-links against the very archives that ship.
#
# ---------------------------------------------------------------------------
# WHAT THE PORT IS, AND WHICH CASES HOLD IT IN PLACE
#
# liburcu selects its architecture from compiler macros in urcu/arch.h and
# urcu/uatomic.h, and both chains end in `#error "Cannot build: unrecognized
# architecture"`. Nothing in either tested __wasm32__, so the package did not
# build here at all. The recipe carries
# 0001-add-wasm32-architecture-support.patch, which adds urcu/arch/wasm32.h and
# urcu/uatomic/wasm32.h and the two dispatch arms; both new headers delegate to
# upstream's generic implementations, as nios2, riscv and loongarch do.
#
# Three groups here are what hold that in place, and each fails a DIFFERENT way
# if the port regresses:
#
#   * header-wasm32-arch / header-wasm32-uatomic -- the two new headers must be
#     INSTALLED, not merely compiled against. They reach the image only via
#     include/Makefile.am, which the patch also edits; a build whose autoreconf
#     did not re-run would compile perfectly and ship a -dev that no consumer
#     can build against. (Observed exactly once, in the native control tree,
#     where automake was too old to regenerate Makefile.in.)
#   * probe-arch-wasm32 -- the dispatch actually selected the wasm32 arm rather
#     than falling into some other arch's header.
#   * probe-cacheline -- the one value wasm32.h overrides. 16, not the generic
#     64: WebAssembly has no cache line, and 64 is an alignment malloc() does
#     not promise on a target whose __BIGGEST_ALIGNMENT__ is 16.
#
# ---------------------------------------------------------------------------
# WHAT THE PROBE DOES NOT TOUCH, AND WHY THAT IS NOT A COVERAGE HOLE
#
# Six liburcu entry points reach pthread_create -- call_rcu(), defer_rcu(),
# rcu_barrier(), CDS_LFHT_AUTO_RESIZE, and the
# start_poll_synchronize_rcu()/poll_state_synchronize_rcu() pair (which reads
# thread-free and is not: urcu-poll-impl.h drives it from a self-requeueing
# call_rcu callback). pthread_create parks the coroutinized thread-start frame
# on this arm and traps at the next park, so a probe that called them would be
# measuring linux-in-the-browser#85 and nothing about liburcu. None of them runs
# at load time or on any default path, so the library's CORE -- read side,
# grace period, pointer publication, atomics, and every data structure -- is
# reachable without them, and the probe reclaims deferred memory the way a
# single-threaded updater is entitled to: synchronize_rcu(), then free().
# BRINTOS-WORKAROUND: linux-in-the-browser#85 revisit -- restore the deferred
# reclaim paths to this suite when threads run.
#
# urcu-bp (the "bulletproof" flavor) is untouched for a second reason: its
# thread registry is backed by mmap(MAP_ANONYMOUS) (brintos/linux#30). Its
# archive is asserted to SHIP, since it is a correct part of the package; it is
# not driven.
#
# ---------------------------------------------------------------------------
# HOW THE PROBE'S 110 VALUES ARE SCORED
#
# 106 of them are diffed against data/liburcu-native.txt, produced by
# src/liburcu_mknative.sh from a native x86_64 build of the IDENTICAL tarball
# and the IDENTICAL probe source. Nothing in that set is a pointer, a size_t
# width, a timestamp or a hash-table traversal order (the lfht checks sort
# before printing, because rculfhash orders buckets by reversed hash bits and
# that order genuinely differs between ILP32 and LP64), so no value in it is
# ALLOWED to differ between the two machines: a disagreement is a defect, not a
# platform difference to reason about.
#
# The other four are properties of the MACHINE and are pinned to the wasm32
# answer instead -- see probe-arch-wasm32, probe-cacheline, probe-bits-per-long
# and probe-membarrier below.
#
# A NATIVE x86_64 RUN OF THIS SUITE SCORES 194 CASES, 188 PASS / 6 FAIL, and
# which six is the demonstration that the arch assertions are load-bearing:
# probe-arch-wasm32, probe-cacheline and probe-bits-per-long MUST be red on
# x86_64 -- a suite where they passed on both arms would be asserting nothing
# about the port. (The other three natively-red cases -- header-wasm32-arch,
# header-wasm32-uatomic, wasm32-cacheline -- are an artifact of the control
# tree only: its automake is too old to regenerate include/Makefile.in, so the
# two new headers are compiled against but not installed there. Any tree that
# autoreconfs, which is every bitbake build, installs them.)

R="${BST_LIBURCU_ROOT:-}"

LIBDIR=$R/usr/lib
INCDIR=$R/usr/include
PCDIR=$R/usr/lib/pkgconfig
PROBE=${BST_LIBURCU_PROBE:-$R/usr/libexec/liburcu-tests/liburcu-probe}
NATIVE=$BST_DATA/liburcu-native.txt

if [ ! -f "$LIBDIR/liburcu.a" ]; then
  bst_skip liburcu/present "liburcu not installed on this image"
  exit 0
fi
bst_ok liburcu/present

# --- the package is whole ----------------------------------------------------
# Eight archives: one per RCU flavor (memb, mb, signal, qsbr, bp), the
# unsuffixed default (memb), the shared wait-free queues, and the concurrent
# data structures. A port that dropped a flavor would look complete to anyone
# only linking against liburcu.a.
for a in liburcu liburcu-memb liburcu-mb liburcu-signal liburcu-qsbr \
         liburcu-bp liburcu-common liburcu-cds; do
  check "liburcu/archive-$a" test -s "$LIBDIR/$a.a"
done

for p in liburcu liburcu-memb liburcu-mb liburcu-signal liburcu-qsbr \
         liburcu-bp liburcu-cds; do
  check "liburcu/pkgconfig-$p" test -s "$PCDIR/$p.pc"
done

# The public headers a consumer names, one per subsystem.
for h in urcu.h urcu/urcu.h urcu/urcu-memb.h urcu/urcu-qsbr.h urcu/urcu-bp.h \
         urcu/arch.h urcu/uatomic.h urcu/compiler.h urcu/system.h \
         urcu/pointer.h urcu/flavor.h urcu/config.h urcu/cds.h urcu/ref.h \
         urcu/list.h urcu/rculist.h urcu/hlist.h urcu/rcuhlist.h \
         urcu/wfcqueue.h urcu/wfstack.h urcu/lfstack.h \
         urcu/rculfhash.h urcu/rculfqueue.h urcu/rculfstack.h \
         urcu/uatomic/generic.h urcu/arch/generic.h; do
  check "liburcu/hdr-$(echo "$h" | tr '/.' '--')" test -f "$INCDIR/$h"
done

# THE TWO HEADERS THIS PORT ADDS. They are installed only because the patch
# also edits include/Makefile.am, so this pair is the assertion that the
# autoreconf ran -- a build that skipped it compiles fine and ships a -dev no
# consumer can use.
check liburcu/header-wasm32-arch    test -f "$INCDIR/urcu/arch/wasm32.h"
check liburcu/header-wasm32-uatomic test -f "$INCDIR/urcu/uatomic/wasm32.h"

# And the dispatch arms that reach them, asserted in the SHIPPED headers rather
# than in the ones the probe was compiled against.
check_out liburcu/dispatch-arch    'urcu/arch/wasm32.h'    cat "$INCDIR/urcu/arch.h"
check_out liburcu/dispatch-uatomic 'urcu/uatomic/wasm32.h' cat "$INCDIR/urcu/uatomic.h"
check_out liburcu/dispatch-macro   'URCU_ARCH_WASM32'      cat "$INCDIR/urcu/arch.h"
# The header must define the override; its VALUE is pinned from the running
# library instead (probe-cacheline), which is the only place it can be read
# after the preprocessor has had it.
check_out liburcu/wasm32-cacheline 'define CAA_CACHE_LINE_SIZE' \
                                   cat "$INCDIR/urcu/arch/wasm32.h"

# Upstream's own architectures must be untouched by the patch: the port adds an
# arm, it does not replace one.
check_out liburcu/dispatch-x86-intact 'urcu/arch/x86.h' cat "$INCDIR/urcu/arch.h"
check liburcu/upstream-arch-x86       test -f "$INCDIR/urcu/arch/x86.h"
check liburcu/upstream-arch-riscv     test -f "$INCDIR/urcu/arch/riscv.h"

# Shape, not absence: this arm converts to shared libraries per recipe
# (BRINTOS-1740), so a .so here is a conversion, not a policy breach.
bst_lib_shape liburcu/no-shared "$LIBDIR/liburcu*.so*"

# --- what is IN the archives, without binutils -------------------------------
# This image ships no `ar` and no `nm`, and reaching for them would not help:
# every archive member here is LLVM bitcode (ThinLTO), so host binutils answers
# "file format not recognized" too. The names are therefore asserted as BYTES --
# ar's member headers and the archive symbol index both store plain ASCII.
#
# Bitcode contains NULs, and GNU grep suppresses a match in a file it decides is
# binary unless -a; busybox grep as shipped does not need it. Probe for the flag
# so this block keeps measuring liburcu rather than the image's grep.
if echo x | grep -qa x 2>/dev/null; then GREPA="grep -qa"; else GREPA="grep -q"; fi
inar() { if $GREPA -- "$2" "$3" 2>/dev/null; then bst_ok "$1"; else bst_notok "$1" "not in $(basename "$3"): $2"; fi; }

inar liburcu/sym-memb-read-lock   urcu_memb_read_lock          "$LIBDIR/liburcu-memb.a"
inar liburcu/sym-memb-sync        urcu_memb_synchronize_rcu    "$LIBDIR/liburcu-memb.a"
inar liburcu/sym-memb-register    urcu_memb_register_thread    "$LIBDIR/liburcu-memb.a"
inar liburcu/sym-memb-flavor      urcu_memb_flavor             "$LIBDIR/liburcu-memb.a"
inar liburcu/sym-memb-membarrier  urcu_memb_has_sys_membarrier "$LIBDIR/liburcu-memb.a"
inar liburcu/sym-default-is-memb  urcu_memb_synchronize_rcu    "$LIBDIR/liburcu.a"
inar liburcu/sym-qsbr-sync        urcu_qsbr_synchronize_rcu    "$LIBDIR/liburcu-qsbr.a"
inar liburcu/sym-bp-read-lock     urcu_bp_read_lock            "$LIBDIR/liburcu-bp.a"
inar liburcu/sym-lfht-new         _cds_lfht_new                "$LIBDIR/liburcu-cds.a"
inar liburcu/sym-lfht-add         cds_lfht_add                 "$LIBDIR/liburcu-cds.a"
inar liburcu/sym-lfht-add-unique  cds_lfht_add_unique          "$LIBDIR/liburcu-cds.a"
inar liburcu/sym-lfht-add-replace cds_lfht_add_replace         "$LIBDIR/liburcu-cds.a"
inar liburcu/sym-lfht-del         cds_lfht_del                 "$LIBDIR/liburcu-cds.a"
inar liburcu/sym-lfht-resize      cds_lfht_resize              "$LIBDIR/liburcu-cds.a"
inar liburcu/sym-lfht-count       cds_lfht_count_nodes         "$LIBDIR/liburcu-cds.a"
inar liburcu/sym-lfq-enqueue      cds_lfq_enqueue_rcu          "$LIBDIR/liburcu-cds.a"
inar liburcu/sym-lfs-push         cds_lfs_push                 "$LIBDIR/liburcu-cds.a"
inar liburcu/sym-wfcq-dequeue     cds_wfcq_dequeue_blocking    "$LIBDIR/liburcu-common.a"
inar liburcu/sym-wfs-pop          cds_wfs_pop_blocking         "$LIBDIR/liburcu-common.a"

# All three rculfhash memory backends are compiled in and selected at run time.
# The image's tables use cds_lfht_mm_order; the mmap backend is present and
# unreachable unless a caller names it through cds_lfht_new_flavor(), which is
# what keeps brintos/linux#30 off this package's path.
inar liburcu/sym-lfht-mm-order    cds_lfht_mm_order            "$LIBDIR/liburcu-cds.a"
inar liburcu/sym-lfht-mm-chunk    cds_lfht_mm_chunk            "$LIBDIR/liburcu-cds.a"
inar liburcu/sym-lfht-mm-mmap     cds_lfht_mm_mmap             "$LIBDIR/liburcu-cds.a"

# Each .pc must name -lurcu-common alongside its own archive: liburcu-common
# carries the wait-free queues and the futex compat every other archive calls
# into, so a .pc that lost it links its consumer against an incomplete library
# and fails at the first undefined symbol rather than at build configuration.
check_out liburcu/pc-cds-name   'Name: Userspace RCU Concurrent Data Structures' \
                                cat "$PCDIR/liburcu-cds.pc"
check_out liburcu/pc-cds-libs   '-lurcu-cds'    cat "$PCDIR/liburcu-cds.pc"
check_out liburcu/pc-cds-common '-lurcu-common' cat "$PCDIR/liburcu-cds.pc"
check_out liburcu/pc-memb-libs  '-lurcu-memb'   cat "$PCDIR/liburcu-memb.pc"
check_out liburcu/pc-version    'Version: 0.14.2' cat "$PCDIR/liburcu.pc"

# --- the library RUNNING, via the in-image probe -----------------------------
for f in "$PROBE" "$NATIVE"; do
  if [ ! -f "$f" ]; then
    bst_skip liburcu/probe-runs "$(basename "$f") absent from the image"
    exit 0
  fi
done

pout=${TMPDIR:-/tmp}/bst-liburcu-out.$$
"$PROBE" > "$pout" 2>&1
prc=$?

if [ "$prc" -eq 0 ]; then
  bst_ok liburcu/probe-runs
elif bst_execfail "$(head -c 200 "$pout" 2>/dev/null)"; then
  bst_unrun liburcu/probe-runs "$(head -c 200 "$pout" 2>/dev/null)"
  rm -f "$pout"
  exit 0
else
  bst_notok liburcu/probe-runs "probe exited $prc"
fi

# The probe prints a terminator, so a run that DIED PARTWAY is distinguishable
# from one that merely disagreed. The per-case loop below reports a missing
# value as "probe stopped before this case", which localises the death to one
# case id instead of smearing a single trap across every remaining case. A
# grace period that never returns lands here, as the one failure mode this
# library has that produces no output at all.
if grep -q '^ALL-URCU-OK$' "$pout" 2>/dev/null; then
  bst_ok liburcu/probe-complete
else
  bst_notok liburcu/probe-complete "no ALL-URCU-OK terminator (last line: $(awk 'END{print $1}' "$pout" 2>/dev/null))"
fi

# --- all 110 probe values, scored in ONE awk pass ----------------------------
#
# ONE awk, not one per case, and that is not a micro-optimisation. A process
# spawn on wasm32 is a fresh module instantiation costing on the order of a
# second, so the obvious shape -- a `$(awk ...)` per value inside a read loop --
# would be 110 spawns and would spend minutes here and very likely overrun the
# suite bound (BRINTOS-333 spent seven minutes on ~150 of them). The whole diff
# is therefore a single program reading the control and the probe output
# together and printing the BST lines itself.
#
# The four machine-dependent ids are pinned here rather than diffed, because
# each is a property of the MACHINE and not of the port -- see the header.
awk '
	# score(<probe id>, <case name>, <expected>) -- the case name is spelled
	# out rather than derived, because these four are pinned assertions
	# about this arm and read differently in a report than the diffed ids.
	function score(id, name, want) {
		if (!(("URCU-" id) in g))
			printf "BST not ok liburcu/%s : no value on target (probe stopped before this case); want=%s\n", name, want
		else if (g["URCU-" id] == want)
			printf "BST ok liburcu/%s\n", name
		else
			printf "BST not ok liburcu/%s : want %s, target %s\n", name, want, g["URCU-" id]
	}

	# first file: the x86_64 control
	NR == FNR {
		if ($1 ~ /^URCU-/) { w[$1] = substr($0, length($1) + 2); ord[++n] = $1 }
		next
	}
	# second file: this run
	$1 ~ /^URCU-/ { g[$1] = substr($0, length($1) + 2) }

	END {
		# The arch dispatch fired and chose wasm32. This is the case that
		# goes red if the patch is dropped and some other architecture
		# header is selected instead -- which would compile, and be wrong.
		score("ARCH-WASM32", "probe-arch-wasm32", "1")
		# The one value urcu/arch/wasm32.h overrides: 16, where x86.h says
		# 128 and the generic default is 64.
		score("CACHELINE", "probe-cacheline", "16")
		score("BITS-PER-LONG", "probe-bits-per-long", "32")

		# WHETHER THIS KERNEL OFFERS sys_membarrier IS NOT A PROPERTY OF THE
		# PORT. liburcu queries MEMBARRIER_CMD_QUERY once at init and, on
		# -ENOSYS, leaves the flag at 0 and promotes the read side to full
		# memory barriers by itself -- a configuration upstream supports.
		# So this asserts only that the query answered one of the two legal
		# values, i.e. that it did not trap and the probe got far enough to
		# print it. That the grace period WORKS is asserted by the diffed
		# B-section cases, whichever mechanism delivered it.
		mb = ("URCU-B13" in g) ? g["URCU-B13"] : "<absent>"
		if (mb == "0" || mb == "1")
			printf "BST ok liburcu/probe-membarrier\n"
		else
			printf "BST not ok liburcu/probe-membarrier : membarrier query answered %s, want 0 or 1\n", mb

		# and the 106 portable values, against the control
		for (i = 1; i <= n; i++) {
			k = ord[i]
			id = substr(k, 6)
			if (!(k in g))
				printf "BST not ok liburcu/%s : no value on target (probe stopped before this case); native=%s\n", id, w[k]
			else if (g[k] == w[k])
				printf "BST ok liburcu/%s\n", id
			else
				printf "BST not ok liburcu/%s : native %s, target %s\n", id, w[k], g[k]
		}
	}
' "$NATIVE" "$pout"

rm -f "$pout"