From ae0afe6198a6b9dc3787d8a6ecc9ab05ecb2b6d6 Mon Sep 17 00:00:00 2001
From: Calvin Rose <calsrose@gmail.com>
Date: Tue, 27 Jan 2026 13:28:52 -0600
Subject: [PATCH] Add janet_decref_abstract_maybe_free

---
 Makefile             |  1 -
 src/core/abstract.c  | 13 +++++++++++++
 src/core/filewatch.c |  8 ++++----
 src/core/gc.c        | 16 ++--------------
 src/include/janet.h  |  3 +++
 5 files changed, 22 insertions(+), 19 deletions(-)

diff --git a/Makefile b/Makefile
index b60c2c90..8e2523b3 100644
--- a/Makefile
+++ b/Makefile
@@ -58,7 +58,6 @@ LDFLAGS?=-rdynamic
 LIBJANET_LDFLAGS?=$(LDFLAGS)
 RUN:=$(RUN)
 
-
 COMMON_CFLAGS:=-std=c99 -Wall -Wextra -Isrc/include -Isrc/conf -fvisibility=hidden -fPIC
 BOOT_CFLAGS:=-DJANET_BOOTSTRAP -DJANET_BUILD=$(JANET_BUILD) -O0 $(COMMON_CFLAGS) -g
 BUILD_CFLAGS:=$(CFLAGS) $(COMMON_CFLAGS)
diff --git a/src/core/abstract.c b/src/core/abstract.c
index 94d69b98..cbda2296 100644
--- a/src/core/abstract.c
+++ b/src/core/abstract.c
@@ -201,4 +201,17 @@ int32_t janet_abstract_decref(void *abst) {
     return janet_atomic_dec(&janet_abstract_head(abst)->gc.data.refcount);
 }
 
+int32_t janet_abstract_decref_maybe_free(void *abst) {
+    int32_t result = janet_abstract_decref(abst);
+    if (0 == result) {
+        JanetAbstractHead *head = janet_abstract_head(abst);
+        if (head->type->gc) {
+            janet_assert(!head->type->gc(head->data, head->size), "finalizer failed");
+        }
+        /* Free memory */
+        janet_free(head);
+    }
+    return result;
+}
+
 #endif
diff --git a/src/core/filewatch.c b/src/core/filewatch.c
index 91d24801..8023271c 100644
--- a/src/core/filewatch.c
+++ b/src/core/filewatch.c
@@ -521,23 +521,23 @@ static void janet_watcher_add(JanetWatcher *watcher, const char *path, uint32_t
     (void) watcher;
     (void) flags;
     (void) path;
-    janet_panic("nyi");
+    janet_panic("filewatch not supported on this platform");
 }
 
 static void janet_watcher_remove(JanetWatcher *watcher, const char *path) {
     (void) watcher;
     (void) path;
-    janet_panic("nyi");
+    janet_panic("filewatch not supported on this platform");
 }
 
 static void janet_watcher_listen(JanetWatcher *watcher) {
     (void) watcher;
-    janet_panic("nyi");
+    janet_panic("filewatch not supported on this platform");
 }
 
 static void janet_watcher_unlisten(JanetWatcher *watcher) {
     (void) watcher;
-    janet_panic("nyi");
+    janet_panic("filewatch not supported on this platform");
 }
 
 #endif
diff --git a/src/core/gc.c b/src/core/gc.c
index 532a9cc6..82d68780 100644
--- a/src/core/gc.c
+++ b/src/core/gc.c
@@ -504,14 +504,7 @@ void janet_sweep() {
                 if (head->type->gcperthread) {
                     janet_assert(!head->type->gcperthread(head->data, head->size), "per-thread finalizer failed");
                 }
-                if (0 == janet_abstract_decref(abst)) {
-                    /* Run finalizer */
-                    if (head->type->gc) {
-                        janet_assert(!head->type->gc(head->data, head->size), "finalizer failed");
-                    }
-                    /* Free memory */
-                    janet_free(janet_abstract_head(abst));
-                }
+                janet_abstract_decref_maybe_free(abst);
 
                 /* Mark as tombstone in place */
                 items[i].key = janet_wrap_nil();
@@ -682,12 +675,7 @@ void janet_clear_memory(void) {
             if (head->type->gcperthread) {
                 janet_assert(!head->type->gcperthread(head->data, head->size), "per-thread finalizer failed");
             }
-            if (0 == janet_abstract_decref(abst)) {
-                if (head->type->gc) {
-                    janet_assert(!head->type->gc(head->data, head->size), "finalizer failed");
-                }
-                janet_free(janet_abstract_head(abst));
-            }
+            janet_abstract_decref_maybe_free(abst);
         }
     }
 #endif
diff --git a/src/include/janet.h b/src/include/janet.h
index 248998d9..10d38dd0 100644
--- a/src/include/janet.h
+++ b/src/include/janet.h
@@ -1482,6 +1482,9 @@ JANET_API void *janet_abstract_threaded(const JanetAbstractType *atype, size_t s
 JANET_API int32_t janet_abstract_incref(void *abst);
 JANET_API int32_t janet_abstract_decref(void *abst);
 
+/* If this returns 0, *abst will be deinitialized and freed */
+JANET_API int32_t janet_abstract_decref_maybe_free(void *abst);
+
 /* Expose channel utilities */
 JANET_API JanetChannel *janet_channel_make(uint32_t limit);
 JANET_API JanetChannel *janet_channel_make_threaded(uint32_t limit);