Implement a stub pthreads library for THREAD_MODEL=single

Makefile

@@ -273,88 +273,93 @@ LIBC_TOP_HALF_MUSL_SOURCES += \
  )
 endif
 
-ifeq ($(THREAD_MODEL), posix)
+# pthreads functions (possibly stub) for either thread model
 LIBC_TOP_HALF_MUSL_SOURCES += \
  $(addprefix $(LIBC_TOP_HALF_MUSL_SRC_DIR)/, \
- env/__init_tls.c \
- stdio/__lockfile.c \
- stdio/flockfile.c \
- stdio/ftrylockfile.c \
- stdio/funlockfile.c \
- thread/__lock.c \
- thread/__wait.c \
- thread/__timedwait.c \
  thread/default_attr.c \
  thread/pthread_attr_destroy.c \
  thread/pthread_attr_get.c \
  thread/pthread_attr_init.c \
  thread/pthread_attr_setdetachstate.c \
  thread/pthread_attr_setguardsize.c \
+ thread/pthread_attr_setschedparam.c \
  thread/pthread_attr_setstack.c \
  thread/pthread_attr_setstacksize.c \
- thread/pthread_attr_setschedparam.c \
- thread/pthread_barrier_destroy.c \
- thread/pthread_barrier_init.c \
- thread/pthread_barrier_wait.c \
  thread/pthread_barrierattr_destroy.c \
  thread/pthread_barrierattr_init.c \
  thread/pthread_barrierattr_setpshared.c \
- thread/pthread_cleanup_push.c \
  thread/pthread_cancel.c \
- thread/pthread_cond_broadcast.c \
- thread/pthread_cond_destroy.c \
- thread/pthread_cond_init.c \
- thread/pthread_cond_signal.c \
- thread/pthread_cond_timedwait.c \
- thread/pthread_cond_wait.c \
+ thread/pthread_cleanup_push.c \
  thread/pthread_condattr_destroy.c \
  thread/pthread_condattr_init.c \
  thread/pthread_condattr_setclock.c \
  thread/pthread_condattr_setpshared.c \
- thread/pthread_create.c \
- thread/pthread_detach.c \
  thread/pthread_equal.c \
- thread/pthread_getattr_np.c \
  thread/pthread_getspecific.c \
- thread/pthread_join.c \
  thread/pthread_key_create.c \
- thread/pthread_mutex_consistent.c \
  thread/pthread_mutex_destroy.c \
  thread/pthread_mutex_init.c \
- thread/pthread_mutex_getprioceiling.c \
- thread/pthread_mutex_lock.c \
- thread/pthread_mutex_timedlock.c \
- thread/pthread_mutex_trylock.c \
- thread/pthread_mutex_unlock.c \
  thread/pthread_mutexattr_destroy.c \
  thread/pthread_mutexattr_init.c \
  thread/pthread_mutexattr_setprotocol.c \
  thread/pthread_mutexattr_setpshared.c \
  thread/pthread_mutexattr_setrobust.c \
  thread/pthread_mutexattr_settype.c \
- thread/pthread_once.c \
  thread/pthread_rwlock_destroy.c \
  thread/pthread_rwlock_init.c \
- thread/pthread_rwlock_rdlock.c \
- thread/pthread_rwlock_timedrdlock.c \
- thread/pthread_rwlock_timedwrlock.c \
- thread/pthread_rwlock_tryrdlock.c \
- thread/pthread_rwlock_trywrlock.c \
- thread/pthread_rwlock_unlock.c \
- thread/pthread_rwlock_wrlock.c \
  thread/pthread_rwlockattr_destroy.c \
  thread/pthread_rwlockattr_init.c \
  thread/pthread_rwlockattr_setpshared.c \
+ thread/pthread_self.c \
  thread/pthread_setcancelstate.c \
  thread/pthread_setcanceltype.c \
  thread/pthread_setspecific.c \
- thread/pthread_self.c \
  thread/pthread_spin_destroy.c \
  thread/pthread_spin_init.c \
+ thread/pthread_testcancel.c \
+ )
+ifeq ($(THREAD_MODEL), posix)
+# pthreads functions needed for actual thread support
+LIBC_TOP_HALF_MUSL_SOURCES += \
+ $(addprefix $(LIBC_TOP_HALF_MUSL_SRC_DIR)/, \
+ env/__init_tls.c \
+ stdio/__lockfile.c \
+ stdio/flockfile.c \
+ stdio/ftrylockfile.c \
+ stdio/funlockfile.c \
+ thread/__lock.c \
+ thread/__wait.c \
+ thread/__timedwait.c \
+ thread/pthread_barrier_destroy.c \
+ thread/pthread_barrier_init.c \
+ thread/pthread_barrier_wait.c \
+ thread/pthread_cond_broadcast.c \
+ thread/pthread_cond_destroy.c \
+ thread/pthread_cond_init.c \
+ thread/pthread_cond_signal.c \
+ thread/pthread_cond_timedwait.c \
+ thread/pthread_cond_wait.c \
+ thread/pthread_create.c \
+ thread/pthread_detach.c \
+ thread/pthread_getattr_np.c \
+ thread/pthread_join.c \
+ thread/pthread_mutex_consistent.c \
+ thread/pthread_mutex_getprioceiling.c \
+ thread/pthread_mutex_lock.c \
+ thread/pthread_mutex_timedlock.c \
+ thread/pthread_mutex_trylock.c \
+ thread/pthread_mutex_unlock.c \
+ thread/pthread_once.c \
+ thread/pthread_rwlock_rdlock.c \
+ thread/pthread_rwlock_timedrdlock.c \
+ thread/pthread_rwlock_timedwrlock.c \
+ thread/pthread_rwlock_tryrdlock.c \
+ thread/pthread_rwlock_trywrlock.c \
+ thread/pthread_rwlock_unlock.c \
+ thread/pthread_rwlock_wrlock.c \
  thread/pthread_spin_lock.c \
  thread/pthread_spin_trylock.c \
  thread/pthread_spin_unlock.c \
- thread/pthread_testcancel.c \
  thread/sem_destroy.c \
  thread/sem_getvalue.c \
  thread/sem_init.c \
@@ -365,6 +370,18 @@ LIBC_TOP_HALF_MUSL_SOURCES += \
  thread/wasm32/wasi_thread_start.s \
  )
 endif
+ifeq ($(THREAD_MODEL), single)
+# pthreads stubs for single-threaded environment
+LIBC_TOP_HALF_MUSL_SOURCES += \
+ $(addprefix $(LIBC_TOP_HALF_DIR)/stub-pthreads/, \
+ barrier.c \
+ condvar.c \
+ mutex.c \
+ rwlock.c \
+ spinlock.c \
+ stub-pthreads.c \
+ )
+endif
 
 MUSL_PRINTSCAN_SOURCES = \
  $(LIBC_TOP_HALF_MUSL_SRC_DIR)/internal/floatscan.c \
@@ -413,10 +430,10 @@ ifeq ($(THREAD_MODEL), posix)
 # https://reviews.llvm.org/D130053).
 CFLAGS += -mthread-model posix -pthread -ftls-model=local-exec
 ASMFLAGS += -matomics
+endif
 
 # Include cloudlib's directory to access the structure definition of clockid_t
 CFLAGS += -I$(LIBC_BOTTOM_HALF_CLOUDLIBC_SRC)
-endif
 
 ifneq ($(LTO),no)
 ifeq ($(LTO),full)

expected/wasm32-wasip1/defined-symbols.txt

@@ -11,6 +11,7 @@ __EINVAL
 __ENOMEM
 __SIG_ERR
 __SIG_IGN
+__acquire_ptc
 __asctime_r
 __assert_fail
 __c_dot_utf8
@@ -34,7 +35,11 @@ __ctype_tolower_loc
 __ctype_toupper_loc
 __cxa_atexit
 __cxa_finalize
+__default_guardsize
+__default_stacksize
 __des_setkey
+__do_cleanup_pop
+__do_cleanup_push
 __do_des
 __duplocale
 __env_rm_add
@@ -175,10 +180,34 @@ __pow_log_data
 __powf_log2_data
 __progname
 __progname_full
+__pthread_cond_timedwait
+__pthread_create
+__pthread_detach
+__pthread_join
+__pthread_key_create
+__pthread_key_delete
+__pthread_mutex_consistent
+__pthread_mutex_lock
+__pthread_mutex_timedlock
+__pthread_mutex_trylock
+__pthread_mutex_unlock
+__pthread_rwlock_rdlock
+__pthread_rwlock_timedrdlock
+__pthread_rwlock_timedwrlock
+__pthread_rwlock_tryrdlock
+__pthread_rwlock_trywrlock
+__pthread_rwlock_unlock
+__pthread_rwlock_wrlock
+__pthread_setcancelstate
+__pthread_testcancel
+__pthread_tsd_main
+__pthread_tsd_run_dtors
+__pthread_tsd_size
 __putenv
 __qsort_r
 __rand48_step
 __reallocarray
+__release_ptc
 __rem_pio2
 __rem_pio2_large
 __rem_pio2f
@@ -234,6 +263,9 @@ __sysv_signal
 __tan
 __tandf
 __tanl
+__testcancel
+__tl_lock
+__tl_unlock
 __tm_to_secs
 __tm_to_tzname
 __tolower_l
@@ -330,6 +362,7 @@ __wasilibc_nocwd_symlinkat
 __wasilibc_nocwd_utimensat
 __wasilibc_open_nomode
 __wasilibc_populate_preopens
+__wasilibc_pthread_self
 __wasilibc_register_preopened_fd
 __wasilibc_rename_newat
 __wasilibc_rename_oldat
@@ -352,6 +385,8 @@ _environ
 _exit
 _flushlbf
 _initialize
+_pthread_cleanup_pop
+_pthread_cleanup_push
 _start
 a64l
 abort
@@ -916,6 +951,89 @@ program_invocation_name
 program_invocation_short_name
 pselect
 psignal
+pthread_attr_destroy
+pthread_attr_getdetachstate
+pthread_attr_getguardsize
+pthread_attr_getschedparam
+pthread_attr_getstack
+pthread_attr_getstacksize
+pthread_attr_init
+pthread_attr_setdetachstate
+pthread_attr_setguardsize
+pthread_attr_setschedparam
+pthread_attr_setstack
+pthread_attr_setstacksize
+pthread_barrier_destroy
+pthread_barrier_init
+pthread_barrier_wait
+pthread_barrierattr_destroy
+pthread_barrierattr_getpshared
+pthread_barrierattr_init
+pthread_barrierattr_setpshared
+pthread_cancel
+pthread_cond_broadcast
+pthread_cond_destroy
+pthread_cond_init
+pthread_cond_signal
+pthread_cond_timedwait
+pthread_cond_wait
+pthread_condattr_destroy
+pthread_condattr_getclock
+pthread_condattr_getpshared
+pthread_condattr_init
+pthread_condattr_setclock
+pthread_condattr_setpshared
+pthread_create
+pthread_detach
+pthread_equal
+pthread_exit
+pthread_getspecific
+pthread_join
+pthread_key_create
+pthread_key_delete
+pthread_mutex_consistent
+pthread_mutex_destroy
+pthread_mutex_init
+pthread_mutex_lock
+pthread_mutex_timedlock
+pthread_mutex_trylock
+pthread_mutex_unlock
+pthread_mutexattr_destroy
+pthread_mutexattr_getprotocol
+pthread_mutexattr_getpshared
+pthread_mutexattr_getrobust
+pthread_mutexattr_gettype
+pthread_mutexattr_init
+pthread_mutexattr_setprotocol
+pthread_mutexattr_setpshared
+pthread_mutexattr_setrobust
+pthread_mutexattr_settype
+pthread_once
+pthread_rwlock_destroy
+pthread_rwlock_init
+pthread_rwlock_rdlock
+pthread_rwlock_timedrdlock
+pthread_rwlock_timedwrlock
+pthread_rwlock_tryrdlock
+pthread_rwlock_trywrlock
+pthread_rwlock_unlock
+pthread_rwlock_wrlock
+pthread_rwlockattr_destroy
+pthread_rwlockattr_getpshared
+pthread_rwlockattr_init
+pthread_rwlockattr_setpshared
+pthread_self
+pthread_setcancelstate
+pthread_setcanceltype
+pthread_setspecific
+pthread_spin_destroy
+pthread_spin_init
+pthread_spin_lock
+pthread_spin_trylock
+pthread_spin_unlock
+pthread_testcancel
+pthread_timedjoin_np
+pthread_tryjoin_np
 putc
 putc_unlocked
 putchar
@@ -1097,6 +1215,8 @@ tfind
 tgamma
 tgammaf
 tgammal
+thrd_current
+thrd_equal
 thrd_sleep
 time
 timegm
@@ -1118,6 +1238,7 @@ truncate
 truncf
 truncl
 tsearch
+tss_get
 twalk
 uname
 ungetc

expected/wasm32-wasip1/predefined-macros.txt

@@ -1429,8 +1429,10 @@
 #define PTHREAD_COND_INITIALIZER {{{0}}}
 #define PTHREAD_CREATE_DETACHED 1
 #define PTHREAD_CREATE_JOINABLE 0
+#define PTHREAD_DESTRUCTOR_ITERATIONS 4
 #define PTHREAD_EXPLICIT_SCHED 1
 #define PTHREAD_INHERIT_SCHED 0
+#define PTHREAD_KEYS_MAX 128
 #define PTHREAD_MUTEX_DEFAULT 0
 #define PTHREAD_MUTEX_ERRORCHECK 2
 #define PTHREAD_MUTEX_INITIALIZER {{{0}}}
@@ -1448,6 +1450,7 @@
 #define PTHREAD_RWLOCK_INITIALIZER {{{0}}}
 #define PTHREAD_SCOPE_PROCESS 1
 #define PTHREAD_SCOPE_SYSTEM 0
+#define PTHREAD_STACK_MIN 2048
 #define PTRBITS (sizeof(char *) * 8)
 #define PTRDIFF_MAX INT32_MAX
 #define PTRDIFF_MIN INT32_MIN