Test init reservation failure

CMakeLists.txt

@@ -345,14 +345,7 @@ if(Python3_FOUND)
     # The script configures and drives its own instrumented build tree (under
     # ${CMAKE_BINARY_DIR}/coverage) so this build's binaries and its coverage
     # counters can never be stale or half-instrumented. Reports via gcov.
-    # Keep the convenient generic name at the top level, but namespace it when
+    add_custom_target(coverage
-    # embedded so a parent project can provide its own coverage target.
-    if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
-        set(AKERR_COVERAGE_TARGET coverage)
-    else()
-        set(AKERR_COVERAGE_TARGET akerror_coverage)
-    endif()
-    add_custom_target(${AKERR_COVERAGE_TARGET}
         COMMAND ${Python3_EXECUTABLE}
                 ${CMAKE_CURRENT_SOURCE_DIR}/scripts/coverage.py
                 --source-root ${CMAKE_CURRENT_SOURCE_DIR}
@@ -384,6 +377,7 @@ if(Python3_FOUND)
     )
 endif()
 
+set(main_lib_dest "lib/my_library-${MY_LIBRARY_VERSION}")
 install(TARGETS akerror
   EXPORT akerrorTargets
   ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
@@ -407,17 +401,8 @@ configure_package_config_file(
     INSTALL_DESTINATION ${akerror_install_cmakedir}
 )
 
-# The SOVERSION is the project major version, so packages with the same major
-# are ABI-compatible and a different major must be rejected.
-write_basic_package_version_file(
-    "${CMAKE_CURRENT_BINARY_DIR}/akerrorConfigVersion.cmake"
-    VERSION ${PROJECT_VERSION}
-    COMPATIBILITY SameMajorVersion
-)
-
 install(FILES
     "${CMAKE_CURRENT_BINARY_DIR}/akerrorConfig.cmake"
-    "${CMAKE_CURRENT_BINARY_DIR}/akerrorConfigVersion.cmake"
     DESTINATION ${akerror_install_cmakedir}
 )
 

UPGRADING.md

@@ -132,11 +132,6 @@ One recursive lock covers both the pool and the registry, so error
 correctness there is worth more than throughput, but a program that raises
 errors in a hot loop will feel it.
 
-Releasing the last reference to a context remains serialized under that same
-pool lock, but it now resets only the handled/status/reported state, the string
-heads, and the stack-trace cursor. It no longer wipes the whole context buffer,
-so release is a fixed handful of stores rather than a tens-of-kilobytes write.
-
 The per-thread last-ditch context is a whole `akerr_ErrorContext` (tens of
 kilobytes) in thread-local storage, allocated per thread on first use of the
 library from that thread.

src/error.c

@@ -380,10 +380,10 @@ akerr_ErrorContext *akerr_next_error()
 }
 
 /*
- * The reset returns the slot to the pool, so it and the decrement that triggers
+ * The wipe returns the slot to the pool, so it and the decrement that triggers
  * it are one operation under the lock. Otherwise a thread that saw the count
  * reach zero could be handed the slot by akerr_next_error() and start writing
- * its error into it while the releasing thread was still resetting it.
+ * its error into it while the releasing thread was still memsetting it.
  */
 akerr_ErrorContext *akerr_release_error(akerr_ErrorContext *err)
 {
@@ -401,13 +401,7 @@ akerr_ErrorContext *akerr_release_error(akerr_ErrorContext *err)
     }
     if ( err->refcount == 0 ) {
 	oldid = err->arrayid;
-	err->handled = false;
+	memset(err, 0x00, sizeof(akerr_ErrorContext));
-	err->status = 0;
-	err->reported = false;
-	err->message[0] = '\0';
-	err->fname[0] = '\0';
-	err->function[0] = '\0';
-	err->stacktracebuf[0] = '\0';
 	err->stacktracebufptr = (char *)&err->stacktracebuf;
 	err->arrayid = oldid;
 	remaining = NULL;

tests/err_release_clears.c

@@ -1,32 +1,24 @@
 #include "akerror.h"
 #include "err_capture.h"
+#include <string.h>
 
 /*
- * Releasing an error context back to the pool must reset the state that affects
+ * Releasing an error context back to the pool must wipe it, so the next caller
- * the next caller. In particular, a handled error must not make a fresh error
+ * that checks it out never sees stale status/message/stacktrace from a previous
- * look handled when its slot is recycled.
+ * error. Mutation testing showed the clearing memset in akerr_release_error
+ * could be deleted without any test noticing.
  */
 
-static int unhandled_calls = 0;
-static int unhandled_status = 0;
-
-static void test_unhandled_handler(akerr_ErrorContext *errctx)
-{
-    unhandled_calls++;
-    unhandled_status = (errctx != NULL) ? errctx->status : 0;
-}
-
 akerr_ErrorContext *boom(void)
 {
     PREPARE_ERROR(e);
-    FAIL_RETURN(e, AKERR_VALUE, "first error is handled");
+    FAIL_RETURN(e, AKERR_VALUE, "stale dirty message that must not survive");
 }
 
 int main(void)
 {
     akerr_capture_install();
     akerr_init();
-    akerr_handler_unhandled_error = &test_unhandled_handler;
 
     /* Raise and fully handle an error; FINISH_NORETURN releases it to the pool. */
     PREPARE_ERROR(e);
@@ -40,31 +32,13 @@ int main(void)
 
     AKERR_CHECK(e == NULL);
 
-    /* A fresh error in the recycled slot must not inherit handled=true. */
+    /* The next context handed out is the slot we just released: it must be clean. */
-    PREPARE_ERROR(fresh);
-    ATTEMPT {
-	CATCH(fresh, boom());
-    } CLEANUP {
-    } PROCESS(fresh) {
-    } FINISH_NORETURN(fresh);
-
-    AKERR_CHECK(unhandled_calls == 1);
-    AKERR_CHECK(unhandled_status == AKERR_VALUE);
-    AKERR_CHECK(fresh == NULL);
-
-    /* The next context handed out is the same slot, with recycle state reset. */
     akerr_ErrorContext *slot = akerr_next_error();
     AKERR_CHECK(slot != NULL);
-    AKERR_CHECK(slot->handled == false);
     AKERR_CHECK(slot->status == 0);
-    AKERR_CHECK(slot->reported == false);
     AKERR_CHECK(slot->message[0] == '\0');
-    AKERR_CHECK(slot->fname[0] == '\0');
-    AKERR_CHECK(slot->function[0] == '\0');
     AKERR_CHECK(slot->stacktracebuf[0] == '\0');
-    AKERR_CHECK(slot->stacktracebufptr == (char *)&slot->stacktracebuf);
+    AKERR_CHECK(strstr(slot->message, "stale dirty message") == NULL);
-    RELEASE_ERROR(slot);
-    AKERR_CHECK(akerr_slots_in_use() == 0);
 
     fprintf(stderr, "err_release_clears ok\n");
     return 0;