Cleanup around script_caller, fix tracking of scripts and ACL logging for RM_Call (#11770)

* Make it clear that current_client is the root client that was called by
  external connection
* add executing_client which is the client that runs the current command
  (can be a module or a script)
* Remove script_caller that was used for commands that have CLIENT_SCRIPT
  to get the client that called the script. in most cases, that's the current_client,
  and in others (when being called from a module), it could be an intermediate
  client when we actually want the original one used by the external connection.

bugfixes:
* RM_Call with C flag should log ACL errors with the requested user rather than
  the one used by the original client, this also solves a crash when RM_Call is used
  with C flag from a detached thread safe context.
* addACLLogEntry would have logged info about the script_caller, but in case the
  script was issued by a module command we actually want the current_client. the
  exception is when RM_Call is called from a timer event, in which case we don't
  have a current_client.

behavior changes:
* client side tracking for scripts now tracks the keys that are read by the script
  instead of the keys that are declared by the caller for EVAL

other changes:
* Log both current_client and executing_client in the crash log.
* remove prepareLuaClient and resetLuaClient, being dead code that was forgotten.
* remove scriptTimeSnapshot and snapshot_time and instead add cmd_time_snapshot
  that serves all commands and is reset only when execution nesting starts.
* remove code to propagate CLIENT_FORCE_REPL from the executed command
  to the script caller since scripts aren't propagated anyway these days and anyway
  this flag wouldn't have had an effect since CLIENT_PREVENT_PROP is added by scriptResetRun.
* fix a module GIL violation issue in afterSleep that was introduced in #10300 (unreleased)

1 files changed, 6 insertions, 3 deletions

diff --git a/src/aof.c b/src/aof.c
index 77ffe70ad..7c8955e0e 100644
--- a/src/aof.c
+++ b/src/aof.c
@@ -1413,8 +1413,10 @@ int loadSingleAppendOnlyFile(char *filename) {
      * to the same file we're about to read. */
     server.aof_state = AOF_OFF;
 
-    client *old_client = server.current_client;
-    fakeClient = server.current_client = createAOFClient();
+    client *old_cur_client = server.current_client;
+    client *old_exec_client = server.executing_client;
+    fakeClient = createAOFClient();
+    server.current_client = server.executing_client = fakeClient;
 
     /* Check if the AOF file is in RDB format (it may be RDB encoded base AOF
      * or old style RDB-preamble AOF). In that case we need to load the RDB file 
@@ -1622,7 +1624,8 @@ fmterr: /* Format error. */
 
 cleanup:
     if (fakeClient) freeClient(fakeClient);
-    server.current_client = old_client;
+    server.current_client = old_cur_client;
+    server.executing_client = old_exec_client;
     fclose(fp);
     sdsfree(aof_filepath);
     return ret;