/**
* Callback function for inputevt_add(). This function pipes the query to
* the server using the pipe in non-blocking mode, partial writes are handled
* appropriately. In case of an unrecoverable error the query pipe will be
* closed and the blocking adns_fallback() will be invoked.
*/
static void
adns_query_callback(void *data, int dest, inputevt_cond_t condition)
{
adns_async_write_t *remain = data;
g_assert(NULL != remain);
g_assert(NULL != remain->buf);
g_assert(remain->pos < remain->size);
g_assert(dest == adns_query_fd);
g_assert(0 != adns_query_event_id);
if (condition & INPUT_EVENT_EXCEPTION) {
g_warning("%s: write exception", G_STRFUNC);
goto abort;
}
while (remain->pos < remain->size) {
ssize_t ret;
size_t n;
n = remain->size - remain->pos;
ret = write(dest, &remain->buf[remain->pos], n);
if (0 == ret) {
errno = ECONNRESET;
ret = (ssize_t) -1;
}
/* FALL THROUGH */
if ((ssize_t) -1 == ret) {
if (!is_temporary_error(errno))
goto error;
return;
}
g_assert(ret > 0);
g_assert(UNSIGNED(ret) <= n);
remain->pos += (size_t) ret;
}
g_assert(remain->pos == remain->size);
inputevt_remove(&adns_query_event_id);
goto done;
error:
g_warning("%s: write() failed: %m", G_STRFUNC);
abort:
g_warning("%s: removed myself", G_STRFUNC);
inputevt_remove(&adns_query_event_id);
fd_close(&adns_query_fd);
g_warning("%s: using fallback", G_STRFUNC);
adns_fallback(&remain->req);
done:
adns_async_write_free(remain);
return;
}
/**
* Change the monitoring condition on the socket.
*/
static void
tls_socket_evt_change(struct gnutella_socket *s, inputevt_cond_t cond)
{
socket_check(s);
g_assert(socket_with_tls(s)); /* No USES yet, may not have handshaked */
g_assert(INPUT_EVENT_EXCEPTION != cond);
if (0 == s->gdk_tag)
return;
if (cond != s->tls.cb_cond) {
int saved_errno = errno;
if (GNET_PROPERTY(tls_debug) > 1) {
int fd = socket_evt_fd(s);
g_debug("tls_socket_evt_change: fd=%d, cond=%s -> %s",
fd, inputevt_cond_to_string(s->tls.cb_cond),
inputevt_cond_to_string(cond));
}
inputevt_remove(&s->gdk_tag);
socket_evt_set(s, cond, s->tls.cb_handler, s->tls.cb_data);
errno = saved_errno;
}
}
/**
* Callback function for inputevt_add(). This function invokes the callback
* function given in DNS query on the client-side i.e., gtk-gnutella itself.
* It handles partial reads if necessary. In case of an unrecoverable error
* the reply pipe will be closed and the callback will be lost.
*/
static void
adns_reply_callback(void *data, int source, inputevt_cond_t condition)
{
static struct adns_response ans;
static void *buf;
static size_t size, pos;
g_assert(NULL == data);
g_assert(condition & INPUT_EVENT_RX);
/*
* Consume all the data available in the pipe, potentially handling
* several pending replies.
*/
for (;;) {
ssize_t ret;
size_t n;
if (pos == size) {
pos = 0;
if (cast_to_pointer(&ans.common) == buf) {
/*
* Finished reading the generic reply header, now read
* the specific part.
*/
g_assert(ADNS_COMMON_MAGIC == ans.common.magic);
if (ans.common.reverse) {
buf = &ans.reply.reverse;
size = sizeof ans.reply.reverse;
} else {
buf = &ans.reply.by_addr;
size = sizeof ans.reply.by_addr;
}
} else {
if (buf) {
/*
* Completed reading the specific part of the reply.
* Inform issuer of request by invoking the user callback.
*/
adns_reply_ready(&ans);
}
/*
* Continue reading the next reply, if any, which will start
* by the generic header.
*/
buf = &ans.common;
size = sizeof ans.common;
ans.common.magic = 0;
}
}
g_assert(buf);
g_assert(size > 0);
g_assert(pos < size);
n = size - pos;
ret = read(source, cast_to_gchar_ptr(buf) + pos, n);
if ((ssize_t) -1 == ret) {
if (!is_temporary_error(errno)) {
g_warning("%s: read() failed: %m", G_STRFUNC);
goto error;
}
break;
} else if (0 == ret) {
g_warning("%s: read() failed: EOF", G_STRFUNC);
goto error;
} else {
g_assert(ret > 0);
g_assert(UNSIGNED(ret) <= n);
pos += (size_t) ret;
}
}
return;
error:
inputevt_remove(&adns_reply_event_id);
g_warning("%s: removed myself", G_STRFUNC);
fd_close(&source);
}