[LibOS,PAL] Rename PalObjectClose() to PalObjectDestroy()

Previous name didn't make it clear that this PAL API not only closes the
associated host resources, but also destroys/frees the PAL handle object
itself. The handle-type-specific callbacks are also renamed from
`close()` to `destroy()`. Also, this function and all its callbacks are
of type `void` now and never return a value (as it's useless anyway).

Signed-off-by: Dmitrii Kuvaiskii <dmitrii.kuvaiskii@intel.com>

Documentation/pal/host-abi.rst

@@ -327,7 +327,7 @@ Objects
 .. doxygenfunction:: PalStreamsWaitEvents
    :project: pal
 
-.. doxygenfunction:: PalObjectClose
+.. doxygenfunction:: PalObjectDestroy
    :project: pal
 
 Miscellaneous

libos/include/libos_lock.h

@@ -28,7 +28,7 @@ static inline bool create_lock(struct libos_lock* l) {
 }
 
 static inline void destroy_lock(struct libos_lock* l) {
-    PalObjectClose(l->lock); // TODO: handle errors
+    PalObjectDestroy(l->lock);
     clear_lock(l);
 }
 

libos/src/bookkeep/libos_handle.c

@@ -522,7 +522,7 @@ void put_handle(struct libos_handle* hdl) {
         free(hdl->uri);
 
         if (hdl->pal_handle) {
-            PalObjectClose(hdl->pal_handle); // TODO: handle errors
+            PalObjectDestroy(hdl->pal_handle);
             hdl->pal_handle = NULL;
         }
 

libos/src/bookkeep/libos_thread.c

@@ -383,7 +383,7 @@ void put_thread(struct libos_thread* thread) {
         free(thread->groups_info.groups);
 
         if (thread->pal_handle && thread->pal_handle != g_pal_public_state->first_thread)
-            PalObjectClose(thread->pal_handle);
+            PalObjectDestroy(thread->pal_handle);
 
         if (thread->handle_map) {
             put_handle_map(thread->handle_map);
@@ -398,7 +398,7 @@ void put_thread(struct libos_thread* thread) {
         /* `signal_altstack` is provided by the user, no need for a clean up. */
 
         if (thread->scheduler_event) {
-            PalObjectClose(thread->scheduler_event);
+            PalObjectDestroy(thread->scheduler_event);
         }
 
         /* `wake_queue` is only meaningful when `thread` is part of some wake up queue (is just

libos/src/fs/chroot/encrypted.c

@@ -263,7 +263,7 @@ static int chroot_encrypted_mkdir(struct libos_dentry* dent, mode_t perm) {
         ret = pal_to_unix_errno(ret);
         goto out;
     }
-    PalObjectClose(palhdl);
+    PalObjectDestroy(palhdl);
 
     inode->type = S_IFDIR;
     inode->perm = perm;
@@ -297,7 +297,7 @@ static int chroot_encrypted_unlink(struct libos_dentry* dent) {
     }
 
     ret = PalStreamDelete(palhdl, PAL_DELETE_ALL);
-    PalObjectClose(palhdl);
+    PalObjectDestroy(palhdl);
     if (ret < 0) {
         ret = pal_to_unix_errno(ret);
         goto out;
@@ -356,7 +356,7 @@ static int chroot_encrypted_chmod(struct libos_dentry* dent, mode_t perm) {
     mode_t host_perm = HOST_PERM(perm);
     PAL_STREAM_ATTR attr = {.share_flags = host_perm};
     ret = PalStreamAttributesSetByHandle(palhdl, &attr);
-    PalObjectClose(palhdl);
+    PalObjectDestroy(palhdl);
     if (ret < 0) {
         ret = pal_to_unix_errno(ret);
         goto out;

libos/src/fs/chroot/fs.c

@@ -224,7 +224,7 @@ static int chroot_do_open(struct libos_handle* hdl, struct libos_dentry* dent, m
         hdl->pos = 0;
         hdl->pal_handle = palhdl;
     } else {
-        PalObjectClose(palhdl);
+        PalObjectDestroy(palhdl);
     }
     ret = 0;
 
@@ -386,7 +386,7 @@ int chroot_readdir(struct libos_dentry* dent, readdir_callback_t callback, void*
 
 out:
     free(buf);
-    PalObjectClose(palhdl);
+    PalObjectDestroy(palhdl);
     return ret;
 }
 
@@ -402,7 +402,7 @@ int chroot_unlink(struct libos_dentry* dent) {
         return ret;
 
     ret = PalStreamDelete(palhdl, PAL_DELETE_ALL);
-    PalObjectClose(palhdl);
+    PalObjectDestroy(palhdl);
     if (ret < 0)
         return pal_to_unix_errno(ret);
 
@@ -426,7 +426,7 @@ static int chroot_rename(struct libos_dentry* old, struct libos_dentry* new) {
         goto out;
 
     ret = PalStreamChangeName(palhdl, new_uri);
-    PalObjectClose(palhdl);
+    PalObjectDestroy(palhdl);
     if (ret < 0) {
         ret = pal_to_unix_errno(ret);
         goto out;
@@ -452,7 +452,7 @@ static int chroot_chmod(struct libos_dentry* dent, mode_t perm) {
     mode_t host_perm = HOST_PERM(perm);
     PAL_STREAM_ATTR attr = {.share_flags = host_perm};
     ret = PalStreamAttributesSetByHandle(palhdl, &attr);
-    PalObjectClose(palhdl);
+    PalObjectDestroy(palhdl);
     if (ret < 0)
         return pal_to_unix_errno(ret);
 

libos/src/fs/libos_fs_encrypted.c

@@ -211,7 +211,7 @@ static int encrypted_file_internal_open(struct libos_encrypted_file* enc, PAL_HA
 out:
     free(normpath);
     if (ret < 0)
-        PalObjectClose(pal_handle);
+        PalObjectDestroy(pal_handle);
     return ret;
 }
 
@@ -242,7 +242,7 @@ static void encrypted_file_internal_close(struct libos_encrypted_file* enc) {
     }
 
     enc->pf = NULL;
-    PalObjectClose(enc->pal_handle);
+    PalObjectDestroy(enc->pal_handle);
     enc->pal_handle = NULL;
     return;
 }

libos/src/fs/libos_fs_lock.c

@@ -618,7 +618,7 @@ int file_lock_set(struct libos_dentry* dent, struct libos_file_lock* file_lock,
 out:
     unlock(&g_fs_lock_lock);
     if (event)
-        PalObjectClose(event);
+        PalObjectDestroy(event);
     return ret;
 }
 

libos/src/fs/socket/fs.c

@@ -23,7 +23,7 @@ static int close(struct libos_handle* handle) {
     free(handle->info.sock.peek.buf);
     /* No need for atomics - we are releasing the last reference, nothing can access it anymore. */
     if (handle->info.sock.pal_handle) {
-        PalObjectClose(handle->info.sock.pal_handle);
+        PalObjectDestroy(handle->info.sock.pal_handle);
     }
     return 0;
 }

libos/src/ipc/libos_ipc.c

@@ -82,7 +82,7 @@ static void put_ipc_connection(struct libos_ipc_connection* conn) {
     refcount_t ref_count = refcount_dec(&conn->ref_count);
 
     if (!ref_count) {
-        PalObjectClose(conn->handle);
+        PalObjectDestroy(conn->handle);
         destroy_lock(&conn->lock);
         free(conn);
     }
@@ -157,7 +157,7 @@ static int ipc_connect(IDTYPE dest, struct libos_ipc_connection** conn_ptr) {
             destroy_lock(&conn->lock);
         }
         if (conn->handle) {
-            PalObjectClose(conn->handle);
+            PalObjectDestroy(conn->handle);
         }
         free(conn);
     }
@@ -311,7 +311,7 @@ int ipc_send_msg_and_get_response(IDTYPE dest, struct libos_ipc_msg* msg, void**
     avl_tree_delete(&g_msg_waiters_tree, &waiter.node);
     unlock(&g_msg_waiters_tree_lock);
     free(waiter.response_data);
-    PalObjectClose(waiter.event);
+    PalObjectDestroy(waiter.event);
     return ret;
 }
 

libos/src/ipc/libos_ipc_worker.c

@@ -110,7 +110,7 @@ static void del_ipc_connection(struct libos_ipc_connection* conn) {
     LISTP_DEL(conn, &g_ipc_connections, list);
     g_ipc_connections_cnt--;
 
-    PalObjectClose(conn->handle);
+    PalObjectDestroy(conn->handle);
 
     free(conn);
 }
@@ -320,7 +320,7 @@ static noreturn void ipc_worker_main(void) {
             ret = read_exact(new_handle, &new_id, sizeof(new_id));
             if (ret < 0) {
                 log_error(LOG_PREFIX "receiving id failed: %s", unix_strerror(ret));
-                PalObjectClose(new_handle);
+                PalObjectDestroy(new_handle);
             } else {
                 ret = add_ipc_connection(new_handle, new_id);
                 if (ret < 0) {
@@ -417,6 +417,6 @@ void terminate_ipc_worker(void) {
 
     put_thread(g_worker_thread);
     g_worker_thread = NULL;
-    PalObjectClose(g_self_ipc_handle);
+    PalObjectDestroy(g_self_ipc_handle);
     g_self_ipc_handle = NULL;
 }

libos/src/libos_checkpoint.c

@@ -659,7 +659,7 @@ int create_process_and_send_checkpoint(migrate_func_t migrate_func,
     }
 
     if (pal_process)
-        PalObjectClose(pal_process);
+        PalObjectDestroy(pal_process);
 
     if (ret < 0) {
         log_error("process creation failed");

libos/src/libos_pollable_event.c

@@ -37,7 +37,7 @@ int create_pollable_event(struct libos_pollable_event* event) {
     } while (ret == -PAL_ERROR_INTERRUPTED);
     if (ret < 0) {
         log_error("PalStreamWaitForClient failed: %s", pal_strerror(ret));
-        PalObjectClose(write_handle);
+        PalObjectDestroy(write_handle);
         ret = pal_to_unix_errno(ret);
         goto out;
     }
@@ -50,10 +50,10 @@ int create_pollable_event(struct libos_pollable_event* event) {
 
 out:;
     int tmp_ret = pal_to_unix_errno(PalStreamDelete(srv_handle, PAL_DELETE_ALL));
-    PalObjectClose(srv_handle);
+    PalObjectDestroy(srv_handle);
     if (!ret && tmp_ret) {
-        PalObjectClose(read_handle);
-        PalObjectClose(write_handle);
+        PalObjectDestroy(read_handle);
+        PalObjectDestroy(write_handle);
         /* Clearing just for sanity. */
         event->read_handle = NULL;
         event->write_handle = NULL;
@@ -62,8 +62,8 @@ out:;
 }
 
 void destroy_pollable_event(struct libos_pollable_event* event) {
-    PalObjectClose(event->read_handle);
-    PalObjectClose(event->write_handle);
+    PalObjectDestroy(event->read_handle);
+    PalObjectDestroy(event->write_handle);
 }
 
 int set_pollable_event(struct libos_pollable_event* event) {

libos/src/libos_rwlock.c

@@ -13,13 +13,13 @@ bool rwlock_create(struct libos_rwlock* l) {
         return false;
     }
     if (PalEventCreate(&l->writer_wait, /*init_signaled=*/false, /*auto_clear=*/true) < 0) {
-        PalObjectClose(l->readers_wait);
+        PalObjectDestroy(l->readers_wait);
         return false;
     }
     l->waiting_readers = 0;
     if (!create_lock(&l->writers_lock)) {
-        PalObjectClose(l->readers_wait);
-        PalObjectClose(l->writer_wait);
+        PalObjectDestroy(l->readers_wait);
+        PalObjectDestroy(l->writer_wait);
         return false;
     }
     return true;
@@ -30,8 +30,8 @@ void rwlock_destroy(struct libos_rwlock* l) {
     assert(l->departing_readers == 0);
     assert(l->waiting_readers == 0);
 
-    PalObjectClose(l->readers_wait);
-    PalObjectClose(l->writer_wait);
+    PalObjectDestroy(l->readers_wait);
+    PalObjectDestroy(l->writer_wait);
     destroy_lock(&l->writers_lock);
 }
 

libos/src/net/ip.c

@@ -179,7 +179,7 @@ static int accept(struct libos_handle* handle, bool is_nonblocking,
                                                                handle->info.sock.protocol,
                                                                is_nonblocking);
     if (!client_handle) {
-        PalObjectClose(client_pal_handle);
+        PalObjectDestroy(client_pal_handle);
         return -ENOMEM;
     }
 

libos/src/net/unix.c

@@ -190,7 +190,7 @@ static int accept(struct libos_handle* handle, bool is_nonblocking,
                                                                handle->info.sock.protocol,
                                                                is_nonblocking);
     if (!client_handle) {
-        PalObjectClose(client_pal_handle);
+        PalObjectDestroy(client_pal_handle);
         return -ENOMEM;
     }
 

libos/src/sync/libos_sync_client.c

@@ -52,7 +52,7 @@ static void put_sync_handle(struct sync_handle* handle) {
         free(handle->data);
         destroy_lock(&handle->use_lock);
         destroy_lock(&handle->prop_lock);
-        PalObjectClose(handle->event);
+        PalObjectDestroy(handle->event);
         free(handle);
     }
 }
@@ -199,7 +199,7 @@ static int sync_init(struct sync_handle* handle, uint64_t id) {
     if (lock_created(&handle->prop_lock))
         destroy_lock(&handle->prop_lock);
     if (handle->event)
-        PalObjectClose(handle->event);
+        PalObjectDestroy(handle->event);
     return ret;
 }
 

libos/src/sys/libos_clone.c

@@ -474,8 +474,8 @@ long libos_syscall_clone(unsigned long flags, unsigned long user_stack_addr, int
     while (!__atomic_load_n(&new_args.is_thread_initialized, __ATOMIC_ACQUIRE)) {
         CPU_RELAX();
     }
-    PalObjectClose(new_args.initialize_event);
-    PalObjectClose(new_args.create_event);
+    PalObjectDestroy(new_args.initialize_event);
+    PalObjectDestroy(new_args.create_event);
 
     put_thread(thread);
     return tid;
@@ -484,9 +484,9 @@ long libos_syscall_clone(unsigned long flags, unsigned long user_stack_addr, int
     if (new_args.thread)
         put_thread(new_args.thread);
     if (new_args.create_event)
-        PalObjectClose(new_args.create_event);
+        PalObjectDestroy(new_args.create_event);
     if (new_args.initialize_event)
-        PalObjectClose(new_args.initialize_event);
+        PalObjectDestroy(new_args.initialize_event);
 failed:
     put_thread(thread);
     return ret;

libos/src/sys/libos_pipe.c

@@ -80,12 +80,12 @@ static int create_pipes(struct libos_handle* srv, struct libos_handle* cli, int
 
 out:;
     int tmp_ret = PalStreamDelete(hdl0, PAL_DELETE_ALL);
-    PalObjectClose(hdl0);
+    PalObjectDestroy(hdl0);
     if (ret || tmp_ret) {
         if (hdl1)
-            PalObjectClose(hdl1);
+            PalObjectDestroy(hdl1);
         if (hdl2)
-            PalObjectClose(hdl2);
+            PalObjectDestroy(hdl2);
 
         free(srv->uri);
         srv->uri = NULL;

pal/include/pal/pal.h

@@ -99,8 +99,6 @@ enum {
     PAL_HANDLE_TYPE_BOUND,
 };
 
-#define PAL_IDX_POISON         ((PAL_IDX)-1) /* PAL identifier poison value */
-
 /********** PAL APIs **********/
 
 struct pal_dns_host_conf_addr {
@@ -826,9 +824,9 @@ int PalStreamsWaitEvents(size_t count, PAL_HANDLE* handle_array, pal_wait_flags_
                          pal_wait_flags_t* ret_events, uint64_t* timeout_us);
 
 /*!
- * \brief Close (deallocate) a PAL handle.
+ * \brief Close and deallocate a PAL handle.
  */
-void PalObjectClose(PAL_HANDLE object_handle);
+void PalObjectDestroy(PAL_HANDLE handle);
 
 /*
  * MISC