/*
* __fstream_printf --
* ANSI C vfprintf.
*/
static int
__fstream_printf(
WT_SESSION_IMPL *session, WT_FSTREAM *fstr, const char *fmt, va_list ap)
{
WT_ITEM *buf;
va_list ap_copy;
size_t len, space;
char *p;
buf = &fstr->buf;
for (;;) {
va_copy(ap_copy, ap);
p = (char *)((uint8_t *)buf->mem + buf->size);
WT_ASSERT(session, buf->memsize >= buf->size);
space = buf->memsize - buf->size;
len = (size_t)vsnprintf(p, space, fmt, ap_copy);
va_end(ap_copy);
if (len < space) {
buf->size += len;
return (buf->size >= WT_STREAM_BUFSIZE ?
__wt_fflush(session, fstr) : 0);
}
WT_RET(__wt_buf_extend(session, buf, buf->size + len + 1));
}
}
/*
* __handle_message_default --
* Default WT_EVENT_HANDLER->handle_message implementation: send to stdout.
*/
static int
__handle_message_default(WT_EVENT_HANDLER *handler,
WT_SESSION *wt_session, const char *message)
{
WT_SESSION_IMPL *session;
WT_UNUSED(handler);
session = (WT_SESSION_IMPL *)wt_session;
WT_RET(__wt_fprintf(session, WT_STDOUT(session), "%s\n", message));
WT_RET(__wt_fflush(session, WT_STDOUT(session)));
return (0);
}
/*
* __handle_error_default --
* Default WT_EVENT_HANDLER->handle_error implementation: send to stderr.
*/
static int
__handle_error_default(WT_EVENT_HANDLER *handler,
WT_SESSION *wt_session, int error, const char *errmsg)
{
WT_SESSION_IMPL *session;
WT_UNUSED(handler);
WT_UNUSED(error);
session = (WT_SESSION_IMPL *)wt_session;
WT_RET(__wt_fprintf(session, WT_STDERR(session), "%s\n", errmsg));
WT_RET(__wt_fflush(session, WT_STDERR(session)));
return (0);
}
/*
* __wt_eventv --
* Report a message to an event handler.
*/
int
__wt_eventv(WT_SESSION_IMPL *session, bool msg_event, int error,
const char *file_name, int line_number, const char *fmt, va_list ap)
{
WT_EVENT_HANDLER *handler;
WT_DECL_RET;
WT_SESSION *wt_session;
struct timespec ts;
size_t len, remain, wlen;
int prefix_cnt;
const char *err, *prefix;
char *end, *p, tid[128];
/*
* We're using a stack buffer because we want error messages no matter
* what, and allocating a WT_ITEM, or the memory it needs, might fail.
*
* !!!
* SECURITY:
* Buffer placed at the end of the stack in case snprintf overflows.
*/
char s[2048];
/*
* !!!
* This function MUST handle a NULL WT_SESSION_IMPL handle.
*
* Without a session, we don't have event handlers or prefixes for the
* error message. Write the error to stderr and call it a day. (It's
* almost impossible for that to happen given how early we allocate the
* first session, but if the allocation of the first session fails, for
* example, we can end up here without a session.)
*/
if (session == NULL) {
WT_RET(__wt_fprintf(session, stderr,
"WiredTiger Error%s%s: ",
error == 0 ? "" : ": ",
error == 0 ? "" : __wt_strerror(session, error, NULL, 0)));
WT_RET(__wt_vfprintf(session, stderr, fmt, ap));
WT_RET(__wt_fprintf(session, stderr, "\n"));
return (__wt_fflush(session, stderr));
}
p = s;
end = s + sizeof(s);
/*
* We have several prefixes for the error message:
* a timestamp and the process and thread ids, the database error
* prefix, the data-source's name, and the session's name. Write them
* as a comma-separate list, followed by a colon.
*/
prefix_cnt = 0;
if (__wt_epoch(session, &ts) == 0) {
__wt_thread_id(tid, sizeof(tid));
remain = WT_PTRDIFF(end, p);
wlen = (size_t)snprintf(p, remain,
"[%" PRIuMAX ":%" PRIuMAX "][%s]",
(uintmax_t)ts.tv_sec, (uintmax_t)ts.tv_nsec / 1000, tid);
p = wlen >= remain ? end : p + wlen;
prefix_cnt = 1;
}
if ((prefix = S2C(session)->error_prefix) != NULL) {
remain = WT_PTRDIFF(end, p);
wlen = (size_t)snprintf(p, remain,
"%s%s", prefix_cnt == 0 ? "" : ", ", prefix);
p = wlen >= remain ? end : p + wlen;
prefix_cnt = 1;
}
prefix = session->dhandle == NULL ? NULL : session->dhandle->name;
if (prefix != NULL) {
remain = WT_PTRDIFF(end, p);
wlen = (size_t)snprintf(p, remain,
"%s%s", prefix_cnt == 0 ? "" : ", ", prefix);
p = wlen >= remain ? end : p + wlen;
prefix_cnt = 1;
}
if ((prefix = session->name) != NULL) {
remain = WT_PTRDIFF(end, p);
wlen = (size_t)snprintf(p, remain,
"%s%s", prefix_cnt == 0 ? "" : ", ", prefix);
p = wlen >= remain ? end : p + wlen;
prefix_cnt = 1;
}
if (prefix_cnt != 0) {
remain = WT_PTRDIFF(end, p);
wlen = (size_t)snprintf(p, remain, ": ");
p = wlen >= remain ? end : p + wlen;
}
if (file_name != NULL) {
remain = WT_PTRDIFF(end, p);
wlen = (size_t)
snprintf(p, remain, "%s, %d: ", file_name, line_number);
p = wlen >= remain ? end : p + wlen;
}
remain = WT_PTRDIFF(end, p);
wlen = (size_t)vsnprintf(p, remain, fmt, ap);
p = wlen >= remain ? end : p + wlen;
if (error != 0) {
/*
* When the engine calls __wt_err on error, it often outputs an
* error message including the string associated with the error
* it's returning. We could change the calls to call __wt_errx,
* but it's simpler to not append an error string if all we are
* doing is duplicating an existing error string.
*
* Use strcmp to compare: both strings are nul-terminated, and
* we don't want to run past the end of the buffer.
*/
err = __wt_strerror(session, error, NULL, 0);
len = strlen(err);
if (WT_PTRDIFF(p, s) < len || strcmp(p - len, err) != 0) {
remain = WT_PTRDIFF(end, p);
(void)snprintf(p, remain, ": %s", err);
}
}
/*
* If a handler fails, return the error status: if we're in the process
* of handling an error, any return value we provide will be ignored by
* our caller, our caller presumably already has an error value it will
* be returning.
*
* If an application-specified or default informational message handler
* fails, complain using the application-specified or default error
* handler.
*
* If an application-specified error message handler fails, complain
* using the default error handler. If the default error handler fails,
* there's nothing to do.
*/
wt_session = (WT_SESSION *)session;
handler = session->event_handler;
if (msg_event) {
ret = handler->handle_message(handler, wt_session, s);
if (ret != 0)
__handler_failure(session, ret, "message", false);
} else {
ret = handler->handle_error(handler, wt_session, error, s);
if (ret != 0 && handler->handle_error != __handle_error_default)
__handler_failure(session, ret, "error", true);
}
return (ret);
}
