Merge pull request 'Release ignored error contexts' (#21) from 14 into main

Reviewed-on: #21

tests/MUTATION.md

@@ -107,7 +107,7 @@ The remaining survivors are dominated by:
 
 * **Equivalent mutants** in `akerr_init`: deleting the `memset`/`NULL` setup of
   file-scope statics (`AKERR_ARRAY_ERROR`, `__akerr_last_ditch`,
-  `__akerr_last_ignored`) changes nothing, because C already zero-initializes
+  `akerr_last_ignored`) changes nothing, because C already zero-initializes
   objects with static storage duration. `int oldid = 0;` → `1` is likewise
   dead: it is overwritten before use, and so is clearing `akerr_initializing`
   at the end of initialization — nothing reads that flag once the once-routine

tests/err_ignore.c

@@ -1,11 +1,8 @@
 #include "akerror.h"
 #include "err_capture.h"
+#include <string.h>
 
-/*
- * IGNORE deliberately swallows an error: it records the context in
- * __akerr_last_ignored, logs it with an "IGNORED ERROR" marker, and lets
- * execution continue.
- */
+/* IGNORE snapshots and logs an error, releases its pool slot, then continues. */
 
 akerr_ErrorContext *boom(void)
 {
@@ -21,11 +18,19 @@ int main(void)
     PREPARE_ERROR(e);
     (void)e;
 
-    IGNORE(boom());
+    /* More failures than the pool has slots must remain safe: a leaking
+     * IGNORE used to exhaust the pool and terminate the process here. The
+     * copied snapshot must also survive the slot being reused on the next
+     * iteration. */
+    for ( int i = 0; i < AKERR_MAX_ARRAY_ERROR + 1; i++ ) {
+	IGNORE(boom());
+	AKERR_CHECK(akerr_last_ignored.status == AKERR_VALUE);
+	AKERR_CHECK(strcmp(akerr_last_ignored.message,
+			  "this error is ignored on purpose") == 0);
+	AKERR_CHECK(akerr_slots_in_use() == 0);
+    }
     reached_after_ignore = 1;
 
-    AKERR_CHECK(__akerr_last_ignored != NULL);
-    AKERR_CHECK(__akerr_last_ignored->status == AKERR_VALUE);
     AKERR_CHECK(reached_after_ignore == 1);
     AKERR_CHECK_CONTAINS("IGNORED ERROR");
     AKERR_CHECK_CONTAINS("this error is ignored on purpose");

tests/err_threads_pool.c

@@ -100,17 +100,21 @@ static void *pool_body(void *raw)
 	one_checkout(arg);
     }
 
-    /* An ignored error is a fact about the thread that ignored it: each thread
-     * must see its own, not the last one any thread swallowed. */
+    /* IGNORE's snapshot is thread-local while logging and remains valid after
+     * release. Concurrent ignored errors must all return their pool slots. */
     IGNORE(ignorable(arg));
-    AKERR_TCHECK(arg, __akerr_last_ignored != NULL);
-    if ( __akerr_last_ignored != NULL ) {
-	AKERR_TCHECK(arg, __akerr_last_ignored->status == AKERR_IO);
-	AKERR_TCHECK(arg, strcmp(__akerr_last_ignored->message, expected) == 0);
+    AKERR_TCHECK(arg, akerr_last_ignored.status == AKERR_IO);
+    AKERR_TCHECK(arg, strcmp(akerr_last_ignored.message, expected) == 0);
+
+    /* Reuse a slot after IGNORE and prove that the copied snapshot did not
+     * become an alias for the newly acquired context. */
+    akerr_ErrorContext *reused = akerr_next_error();
+    AKERR_TCHECK(arg, reused != NULL);
+    if ( reused != NULL ) {
+	RELEASE_ERROR(reused);
     }
-    /* IGNORE keeps the reference by design; hand it back so the pool is empty
-     * at the end of the test. */
-    RELEASE_ERROR(__akerr_last_ignored);
+    AKERR_TCHECK(arg, akerr_last_ignored.status == AKERR_IO);
+    AKERR_TCHECK(arg, strcmp(akerr_last_ignored.message, expected) == 0);
 
     return NULL;
 }