Merge remote-tracking branch 'origin/topic/awelzel/stmt-extern'

* origin/topic/awelzel/stmt-extern:
  Bump zeekjs for STMT_ANY deprecation
  Stmt: Deprecate STMT_ANY
  Stmt: Introduce STMT_EXTERN

CHANGES

@@ -1,3 +1,35 @@
+6.2.0-dev.533 | 2024-02-08 15:12:16 +0100
+
+  * Bump zeekjs for STMT_ANY deprecation (Arne Welzel, Corelight)
+
+  * GH-3529: Stmt: Deprecate STMT_ANY (Arne Welzel, Corelight)
+
+    This isn't used in-tree and has been misused by some external plugins
+    of mine (zeekjs and zeek-perf-support) for their own Stmt subclasses.
+    These plugins should be updated to use the new STMT_EXTERN statement.
+
+    Handle STMT_ANY explicitly in stmt_name() for the time being
+    to fix #3529 until we remove STMT_ANY for good.
+
+  * Stmt: Introduce STMT_EXTERN (Arne Welzel, Corelight)
+
+    It's currently possible for plugin's to implement their own statement
+    subclasses and override the Exec() implementation. This has been leveraged
+    by ZeekJS [1] and zeek-perf-support [2] as well as a private WASM plugin.
+    All of these used STMT_ANY as the tag of their own statement subclasses.
+
+    With STMT_EXTERN, we make the possibility to add external code into the AST
+    somewhat more supported. It's all in detail space and plugin authors have
+    no guarantee for stability, but it seems such a powerful extension point
+    that IMO we should keep it.
+
+    I'm conscious there's the broader topic how this interacts with ZAM
+    optimization like in-lining or rewriting of statements. However, this
+    already applies to the STMT_ANY usage of the mentioned plugins.
+
+    [1] https://github.com/corelight/zeekjs
+    [2] https://github.com/zeek/zeek-perf-support
+
 6.2.0-dev.528 | 2024-02-07 12:45:30 -0700
 
   * Update .gitignore to add Emacs and Vim temp files (Tim Wojtulewicz)

VERSION

@@ -1 +1 @@
-6.2.0-dev.528
+6.2.0-dev.533

auxil/zeekjs

@@ -1 +1 @@
-Subproject commit 70d88f4b10e36f8715eb0f2a25eb0fc0eb4fce37
+Subproject commit 84826e2f733f69843fb470328877c27758ebe164

src/Stmt.cc

@@ -52,8 +52,15 @@ const char* stmt_name(StmtTag t) {
         "ZAM",
         "null",
         "assert",
+        "extern",
     };
 
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+    if ( int(t) == STMT_ANY )
+        return "any";
+#pragma GCC diagnostic pop
+
     return stmt_names[int(t)];
 }
 

src/StmtEnums.h

@@ -6,7 +6,7 @@ namespace zeek::detail {
 
 // These are in a separate file to break circular dependences
 enum StmtTag {
-    STMT_ANY = -1,
+    STMT_ANY [[deprecated("Remove in v7.1 - Unused and plugins should use STMT_EXTERN.")]] = -1,
     STMT_ALARM, // Does no longer exist but kept to create enums consistent.
     STMT_PRINT,
     STMT_EVENT,
@@ -31,7 +31,8 @@ enum StmtTag {
     STMT_ZAM,           // a ZAM function body
     STMT_NULL,
     STMT_ASSERT,
-#define NUM_STMTS (int(STMT_ASSERT) + 1)
+    STMT_EXTERN, // for custom Stmt subclasses provided by plugins
+#define NUM_STMTS (int(STMT_EXTERN) + 1)
 };
 
 enum StmtFlowType {