Two root causes prevented iperf3 tests from running:
1. argv[0] bug: iperf_parse_arguments() expects argv[0] to be the
program name. We passed Dart args directly, so argv[0] was '-c',
which iperf3 misinterpreted as the program name → 'Argument parse
error: must either be a client (-c) or server (-s)'. Fixed by
prepending "iperf3" as argv[0] and shifting user args to argv[1+].
2. Signal handling: iperf_catch_sigend() installs handlers that use
longjmp() to a jmp_buf, but we never initialized the buffer with
setjmp(). Any signal during iperf_run_client() caused SIGSEGV or
hang. Added setjmp/longjmp wrapper matching main.c's pattern,
SIGPIPE=SIG_IGN, and a 30s connect_timeout to avoid DNS hangs.
Also extracted iperf_cleanup_and_signal() to deduplicate the
normal-return and longjmp paths. Added diagnostic logging to
IperfRunner.kt's library loading for faster future debugging.
The root cause of the SIGBUS (alignment fault) crash was casting jmethodID
values to function pointers and invoking them directly. jmethodID is an
opaque JNI type that must only be used via CallVoidMethod/CallObjectMethod
etc. Calling it as a function pointer dereferences garbage memory, causing
SIGBUS at address 0xb1.
Changes:
- Replace function pointer typedefs (output_callback_t etc.) with a struct
storing JNIEnv + callback global ref + jmethodIDs
- All callbacks now go through CallVoidMethod(env, ref, mid, ...)
- Remove getTestProgress() (never used, unused start_time workaround)
- Fix Kotlin arg cast: List<String> -> toTypedArray() (ClassCastException)
- Update UI default server to speedtest.uztelecom.uz
- Switch from bundled iperf3 binary (Process.start) to JNI compilation
- iperf3 3.21 source API was incompatible (start_time, iperf_strerror, etc.)
- iperf3 3.19 source is proven to work (used by CellularLab)
- CMakeLists.txt updated: config.h generated into cpp/iperf/ for correct include paths
- iperf_jni.c fixed for 3.19 API (no start_time on iperf_test)
- getTestProgress() returns g_test->duration as fallback (no real-time elapsed tracking yet)
- NDK CMake pinned to 3.22.1
- UI layer updated: removed Iperf3BinaryPathProvider references
- Tests updated: TestRunViewModelTest matches new service interface
- pubspec.yaml: removed iperf3 assets bundle, added http dependency
- AndroidManifest: INTERNET permission (needed for hostname resolution)