Add error dialog for critical errors on Windows

doc/src/devdocs/debuggingtips.md

@@ -128,7 +128,7 @@ The corresponding LLDB command is (after the process is started):
 (lldb) pro hand -p true -s false -n false SIGSEGV
 ```
 
-If you are debugging a segfault with threaded code, you can set a breakpoint on `jl_critical_error`
+If you are debugging a segfault with threaded code, you can set a breakpoint on `jl_fprint_critical_error`
 (`sigdie_handler` should also work on Linux and BSD) in order to only catch the actual segfault
 rather than the GC synchronization points.
 

src/signals-win.c

@@ -92,9 +92,29 @@ void __cdecl crt_sig_handler(int sig, int num)
         }
         memset(&Context, 0, sizeof(Context));
         RtlCaptureContext(&Context);
+
+        ios_t s;
+        ios_mem(&s, 1024);
         if (sig == SIGILL)
-            jl_fprint_sigill(ios_stderr, &Context);
-        jl_fprint_critical_error(ios_stderr, sig, 0, &Context, jl_get_current_task());
+            jl_fprint_sigill(&s, &Context);
+        jl_fprint_critical_error(&s, sig, 0, &Context, jl_get_current_task());
+
+        // First write to stderr
+        ios_write_direct(ios_stderr, &s);
+
+        // Then write to Application log
+        HANDLE event_source = RegisterEventSourceW(NULL, L"julia");
+        if (event_source != INVALID_HANDLE_VALUE) {
+            ios_putc('\0', &s);
+            const wchar_t *strings[] = { ios_utf8_to_wchar(s.buf) };
+            ReportEventW(
+                event_source, EVENTLOG_ERROR_TYPE, /* category */ 0, /* event_id */ (DWORD)0xE0000000L,
+               /* user_sid */ NULL, /* n_strings */ 1, /* data_size */ 0, strings, /* data */ NULL
+            );
+            MessageBoxW(NULL, /* message */ L"error: libjulia received a fatal signal.\n\n"
+                                            L"See Application log in Event Viewer for more information.",
+                        /* title */ L"fatal error in libjulia", MB_OK | MB_ICONEXCLAMATION | MB_SYSTEMMODAL);
+        }
         raise(sig);
     }
 }
@@ -278,59 +298,88 @@ LONG WINAPI jl_exception_handler(struct _EXCEPTION_POINTERS *ExceptionInfo)
             break;
         }
     }
+    ios_t full_error, summary;
+    ios_mem(&full_error, 1024);
     if (ExceptionInfo->ExceptionRecord->ExceptionCode == EXCEPTION_ILLEGAL_INSTRUCTION) {
-        jl_safe_printf("\n");
-        jl_fprint_sigill(ios_stderr, ExceptionInfo->ContextRecord);
+        jl_safe_fprintf(&full_error, "\n");
+        jl_fprint_sigill(&full_error, ExceptionInfo->ContextRecord);
     }
-    jl_safe_printf("\nPlease submit a bug report with steps to reproduce this fault, and any error messages that follow (in their entirety). Thanks.\nException: ");
+    jl_safe_fprintf(&full_error, "\nPlease submit a bug report with steps to reproduce this fault, and any error messages that follow (in their entirety). Thanks.\n");
+    ios_mem(&summary, 128);
+    jl_safe_fprintf(&summary, "Exception: ");
     switch (ExceptionInfo->ExceptionRecord->ExceptionCode) {
     case EXCEPTION_ACCESS_VIOLATION:
-        jl_safe_printf("EXCEPTION_ACCESS_VIOLATION"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_ACCESS_VIOLATION"); break;
     case EXCEPTION_ARRAY_BOUNDS_EXCEEDED:
-        jl_safe_printf("EXCEPTION_ARRAY_BOUNDS_EXCEEDED"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_ARRAY_BOUNDS_EXCEEDED"); break;
     case EXCEPTION_BREAKPOINT:
-        jl_safe_printf("EXCEPTION_BREAKPOINT"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_BREAKPOINT"); break;
     case EXCEPTION_DATATYPE_MISALIGNMENT:
-        jl_safe_printf("EXCEPTION_DATATYPE_MISALIGNMENT"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_DATATYPE_MISALIGNMENT"); break;
     case EXCEPTION_FLT_DENORMAL_OPERAND:
-        jl_safe_printf("EXCEPTION_FLT_DENORMAL_OPERAND"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_FLT_DENORMAL_OPERAND"); break;
     case EXCEPTION_FLT_DIVIDE_BY_ZERO:
-        jl_safe_printf("EXCEPTION_FLT_DIVIDE_BY_ZERO"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_FLT_DIVIDE_BY_ZERO"); break;
     case EXCEPTION_FLT_INEXACT_RESULT:
-        jl_safe_printf("EXCEPTION_FLT_INEXACT_RESULT"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_FLT_INEXACT_RESULT"); break;
     case EXCEPTION_FLT_INVALID_OPERATION:
-        jl_safe_printf("EXCEPTION_FLT_INVALID_OPERATION"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_FLT_INVALID_OPERATION"); break;
     case EXCEPTION_FLT_OVERFLOW:
-        jl_safe_printf("EXCEPTION_FLT_OVERFLOW"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_FLT_OVERFLOW"); break;
     case EXCEPTION_FLT_STACK_CHECK:
-        jl_safe_printf("EXCEPTION_FLT_STACK_CHECK"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_FLT_STACK_CHECK"); break;
     case EXCEPTION_FLT_UNDERFLOW:
-        jl_safe_printf("EXCEPTION_FLT_UNDERFLOW"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_FLT_UNDERFLOW"); break;
     case EXCEPTION_ILLEGAL_INSTRUCTION:
-        jl_safe_printf("EXCEPTION_ILLEGAL_INSTRUCTION"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_ILLEGAL_INSTRUCTION"); break;
     case EXCEPTION_IN_PAGE_ERROR:
-        jl_safe_printf("EXCEPTION_IN_PAGE_ERROR"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_IN_PAGE_ERROR"); break;
     case EXCEPTION_INT_DIVIDE_BY_ZERO:
-        jl_safe_printf("EXCEPTION_INT_DIVIDE_BY_ZERO"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_INT_DIVIDE_BY_ZERO"); break;
     case EXCEPTION_INT_OVERFLOW:
-        jl_safe_printf("EXCEPTION_INT_OVERFLOW"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_INT_OVERFLOW"); break;
     case EXCEPTION_INVALID_DISPOSITION:
-        jl_safe_printf("EXCEPTION_INVALID_DISPOSITION"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_INVALID_DISPOSITION"); break;
     case EXCEPTION_NONCONTINUABLE_EXCEPTION:
-        jl_safe_printf("EXCEPTION_NONCONTINUABLE_EXCEPTION"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_NONCONTINUABLE_EXCEPTION"); break;
     case EXCEPTION_PRIV_INSTRUCTION:
-        jl_safe_printf("EXCEPTION_PRIV_INSTRUCTION"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_PRIV_INSTRUCTION"); break;
     case EXCEPTION_SINGLE_STEP:
-        jl_safe_printf("EXCEPTION_SINGLE_STEP"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_SINGLE_STEP"); break;
     case EXCEPTION_STACK_OVERFLOW:
-        jl_safe_printf("EXCEPTION_STACK_OVERFLOW"); break;
+        jl_safe_fprintf(&summary, "EXCEPTION_STACK_OVERFLOW"); break;
     default:
-        jl_safe_printf("UNKNOWN"); break;
+        jl_safe_fprintf(&summary, "UNKNOWN"); break;
+    }
+    jl_safe_fprintf(&summary, " at 0x%zx -- ", (size_t)ExceptionInfo->ExceptionRecord->ExceptionAddress);
+    jl_fprint_native_codeloc(&summary, (uintptr_t)ExceptionInfo->ExceptionRecord->ExceptionAddress);
+    ios_write(&full_error, summary.buf, ios_pos(&summary));
+
+    jl_fprint_critical_error(&full_error, 0, 0, ExceptionInfo->ContextRecord, ct);
+
+    // First print to STDERR
+    ios_write_direct(ios_stderr, &full_error);
+
+    // Secondly print to Application log
+    HANDLE event_source = RegisterEventSourceW(NULL, L"julia");
+    if (event_source != INVALID_HANDLE_VALUE) {
+        ios_putc('\0', &full_error);
+        const wchar_t *strings[] = {
+            ios_utf8_to_wchar(full_error.buf),
+        };
+        ReportEventW(
+            event_source, EVENTLOG_ERROR_TYPE, /* category */ 0, /* event_id */ (DWORD)0xE0000000L,
+           /* user_sid */ NULL, /* n_strings */ 1, /* data_size */ 0, strings, /* data */ NULL
+        );
+
+        ios_puts("\nSee Application log in Event Viewer for more information.\n", &summary);
+        ios_putc('\0', &summary);
+        MessageBoxW(NULL, /* message */ ios_utf8_to_wchar(summary.buf), /* title */ L"fatal error in libjulia",
+                    MB_OK | MB_ICONEXCLAMATION | MB_SYSTEMMODAL);
     }
-    jl_safe_printf(" at 0x%zx -- ", (size_t)ExceptionInfo->ExceptionRecord->ExceptionAddress);
-    jl_fprint_native_codeloc(ios_stderr, (uintptr_t)ExceptionInfo->ExceptionRecord->ExceptionAddress);
 
-    jl_fprint_critical_error(ios_stderr, 0, 0, ExceptionInfo->ContextRecord, ct);
+    ios_close(&summary);
+    ios_close(&full_error);
     static int recursion = 0;
     if (recursion++)
         exit(1);

src/staticdata.c

@@ -3053,8 +3053,6 @@ JL_DLLEXPORT void jl_create_system_image(void **_native_data, jl_array_t *workli
     return;
 }
 
-JL_DLLEXPORT size_t ios_write_direct(ios_t *dest, ios_t *src);
-
 // Takes in a path of the form "usr/lib/julia/sys.so" (jl_restore_system_image should be passed the same string)
 JL_DLLEXPORT void jl_preload_sysimg_so(const char *fname)
 {

src/support/ios.c

@@ -988,6 +988,24 @@ ios_t *ios_file(ios_t *s, const char *fname, int rd, int wr, int create, int tru
     return NULL;
 }
 
+#ifdef _OS_WINDOWS_
+const wchar_t *ios_utf8_to_wchar(const char *str) {
+    /* Fast-path empty strings, as MultiByteToWideChar() returns zero for them. */
+    if (str[0] == '\0') {
+        wchar_t *wstr = (wchar_t *)malloc(sizeof(wchar_t));
+        wstr[0] = L'\0';
+        return wstr;
+    }
+    size_t len = MultiByteToWideChar(CP_UTF8, 0, str, -1, NULL, 0);
+    if (!len)
+        return NULL;
+    wchar_t *wstr = (wchar_t *)malloc(len * sizeof(wchar_t));
+    if (!wstr || !MultiByteToWideChar(CP_UTF8, 0, str, -1, wstr, len))
+        return NULL;
+    return wstr;
+}
+#endif // _OS_WINDOWS_
+
 // Portable ios analogue of mkstemp: modifies fname to replace
 // trailing XXXX's with unique ID and returns the file handle s
 // for writing and reading.

src/support/ios.h

@@ -88,6 +88,7 @@ extern void (*ios_set_io_wait_func)(int);
 JL_DLLEXPORT size_t ios_read(ios_t *s, char *dest, size_t n) JL_NOTSAFEPOINT;
 JL_DLLEXPORT size_t ios_readall(ios_t *s, char *dest, size_t n) JL_NOTSAFEPOINT;
 JL_DLLEXPORT size_t ios_write(ios_t *s, const char *data, size_t n) JL_NOTSAFEPOINT;
+JL_DLLEXPORT size_t ios_write_direct(ios_t *dest, ios_t *src) JL_NOTSAFEPOINT;
 JL_DLLEXPORT int64_t ios_seek(ios_t *s, int64_t pos) JL_NOTSAFEPOINT; // absolute seek
 JL_DLLEXPORT int64_t ios_seek_end(ios_t *s) JL_NOTSAFEPOINT;
 JL_DLLEXPORT int64_t ios_skip(ios_t *s, int64_t offs);  // relative seek
@@ -153,6 +154,10 @@ int ios_ungetc(int c, ios_t *s);
 //wint_t ios_ungetwc(ios_t *s, wint_t wc);
 #define ios_puts(str, s) ios_write(s, str, strlen(str))
 
+#ifdef _OS_WINDOWS_
+const wchar_t *ios_utf8_to_wchar(const char *str);
+#endif
+
 /*
   With memory streams, mixed reads and writes are equivalent to performing
   sequences of *p++, as either an lvalue or rvalue. File streams behave

src/task.c

@@ -689,11 +689,34 @@ JL_DLLEXPORT JL_NORETURN void jl_no_exc_handler(jl_value_t *e, jl_task_t *ct)
     if (!e)
         e = jl_current_exception(ct);
 
-    jl_printf((JL_STREAM*)STDERR_FILENO, "fatal: error thrown and no exception handler available.\n");
-    jl_static_show((JL_STREAM*)STDERR_FILENO, e);
-    jl_printf((JL_STREAM*)STDERR_FILENO, "\n");
-    jl_fprint_backtrace(ios_stderr);
+    // Write error to memory first
+    ios_t s;
+    ios_mem(&s, 1024);
+    jl_safe_fprintf(&s, "fatal: error thrown and no exception handler available.\n");
+    jl_static_show((JL_STREAM*)&s, e);
+    jl_safe_fprintf(&s, "\n");
+    jl_fprint_backtrace(&s);
+
+    // Then to STDERR
+    ios_write_direct(ios_stderr, &s);
+
+    // Finally write to system log (if supported)
+#ifdef _OS_WINDOWS_
+    HANDLE event_source = RegisterEventSourceW(NULL, L"julia");
+    if (event_source != INVALID_HANDLE_VALUE) {
+        ios_putc('\0', &s);
+        const wchar_t *strings[] = { ios_utf8_to_wchar(s.buf) };
+        ReportEventW(
+            event_source, EVENTLOG_ERROR_TYPE, /* category */ 0, /* event_id */ (DWORD)0xE0000000L,
+           /* user_sid */ NULL, /* n_strings */ 1, /* data_size */ 0, strings, /* data */ NULL
+        );
+        MessageBoxW(NULL, /* message */ L"fatal: error thrown and no exception handler available\n\n"
+                                        L"See Application log in Event Viewer for more information.",
+                    /* title */ L"fatal error in libjulia", MB_OK | MB_ICONEXCLAMATION | MB_SYSTEMMODAL);
+    }
+#endif
 
+    ios_close(&s);
     if (ct == NULL)
         jl_raise(6);
     jl_exit(1);