win: set fallback message if FormatMessage fails

FormatMessage can fail, e.g. with ERROR_MUI_FILE_NOT_FOUND. In this case
no error message was set and uv_dlerror wrongly returned "no error".

With this patch the fallback error message "error: <errorno>" is
generated when FormatMessage fails.

PR-URL: https://github.com/libuv/libuv/pull/59
Reviewed-By: Bert Belder <bertbelder@gmail.com>
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>
This commit is contained in:
Marc Schlaich 2014-12-11 10:26:15 +01:00 committed by Bert Belder
parent 4298c1fb2c
commit 6eb2eaa753

View File

@ -69,17 +69,37 @@ const char* uv_dlerror(uv_lib_t* lib) {
}
static void uv__format_fallback_error(uv_lib_t* lib, int errorno){
DWORD_PTR args[1] = { (DWORD_PTR) errorno };
LPSTR fallback_error = "error: %1!d!";
FormatMessageA(FORMAT_MESSAGE_FROM_STRING |
FORMAT_MESSAGE_ARGUMENT_ARRAY |
FORMAT_MESSAGE_ALLOCATE_BUFFER,
fallback_error, 0, 0,
(LPSTR) &lib->errmsg,
0, (va_list*) args);
}
static int uv__dlerror(uv_lib_t* lib, int errorno) {
DWORD res;
if (lib->errmsg) {
LocalFree((void*)lib->errmsg);
lib->errmsg = NULL;
}
if (errorno) {
FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM |
FORMAT_MESSAGE_IGNORE_INSERTS, NULL, errorno,
MAKELANGID(LANG_ENGLISH, SUBLANG_ENGLISH_US),
(LPSTR)&lib->errmsg, 0, NULL);
res = FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER |
FORMAT_MESSAGE_FROM_SYSTEM |
FORMAT_MESSAGE_IGNORE_INSERTS, NULL, errorno,
MAKELANGID(LANG_ENGLISH, SUBLANG_ENGLISH_US),
(LPSTR) &lib->errmsg, 0, NULL);
if (!res) {
uv__format_fallback_error(lib, errorno);
}
}
return errorno ? -1 : 0;