/**
* @brief Requeue an imap connection for processing, or log it out if there was an error or excess of protocol violations.
* @param con a pointer to the connection object of the imap session.
* @return This function returns no value.
*/
void imap_requeue(connection_t *con) {
if (!status() || con_status(con) < 0 || con_status(con) == 2 || con->protocol.violations > con->server->violations.cutoff) {
enqueue(&imap_logout, con);
}
else {
enqueue(&imap_process, con);
}
return;
}
/**
* @brief Gracefully destroy a POP3 session, whether because of an error or in response to a user QUIT command.
* @param con the POP3 client connection to be shut down.
* @brief This function returns no value.
*/
void pop_quit(connection_t *con) {
if (con_status(con) == 2) {
con_write_bl(con, "-ERR Unexpected connection shutdown detected. Goodbye.\r\n", 56);
}
else if (con_status(con) >= 0) {
con_write_bl(con, "+OK Goodbye.\r\n", 14);
}
else {
con_write_bl(con, "-ERR Network connection failure.\r\n", 34);
}
con_destroy(con);
return;
}
/**
* @brief Read a line of input from a network connection.
* @note This function handles reading data from both regular and ssl connections.
* This function continually attempts to read incoming data from the specified connection until a \n terminated line of input is received.
* If a new line is read, the length of that line is returned to the caller, including the trailing \n.
* If the read returns -1 and wasn't caused by a syscall interruption or blocking error, -1 is returned, and the connection status is set to -1.
* If the read returns 0 and wasn't caused by a syscall interruption or blocking error, -2 is returned, and the connection status is set to 2.
* Once a \n character is reached, the length of the current line of input is returned to the user, and the connection status is set to 1.
* @param con the network connection across which the line of data will be read.
* @return -1 on general failure, -2 if the connection was reset, or the length of the current line of input, including the trailing new line character.
*/
int64_t con_read_line(connection_t *con, bool_t block) {
ssize_t bytes = 0;
int_t counter = 0;
bool_t line = false;
if (!con || con->network.sockd == -1 || con_status(con) < 0) {
if (con) con->network.status = -1;
return -1;
}
// Check for an existing network buffer. If there isn't one, try creating it.
else if (!con->network.buffer && !con_init_network_buffer(con)) {
con->network.status = -1;
return -1;
}
// Check if we have received more data than just what is in the current line of input.
else if (pl_length_get(con->network.line) && st_length_get(con->network.buffer) > pl_length_get(con->network.line)) {
// If so, move the unused "new" data after the current line marker to the front of the buffer.
mm_move(st_data_get(con->network.buffer), st_data_get(con->network.buffer) + pl_length_get(con->network.line),
st_length_get(con->network.buffer) - pl_length_get(con->network.line));
// Update the buffer length.
st_length_set(con->network.buffer, st_length_get(con->network.buffer) - pl_length_get(con->network.line));
// Check whether the data we just moved contains a complete line.
if (!pl_empty((con->network.line = line_pl_st(con->network.buffer, 0)))) {
con->network.status = 1;
return pl_length_get(con->network.line);
}
}
// Otherwise reset the buffer and line lengths to zero.
else {
st_length_set(con->network.buffer, 0);
con->network.line = pl_null();
}
// Loop until we get a complete line, an error, or the buffer is filled.
do {
// blocking = st_length_get(con->network.buffer) ? false : true;
block = true;
if (con->network.tls) {
bytes = tls_read(con->network.tls, st_char_get(con->network.buffer) + st_length_get(con->network.buffer),
st_avail_get(con->network.buffer) - st_length_get(con->network.buffer), block);
}
else {
bytes = tcp_read(con->network.sockd, st_char_get(con->network.buffer) + st_length_get(con->network.buffer),
st_avail_get(con->network.buffer) - st_length_get(con->network.buffer), block);
}
// We actually read in data, so we need to update the buffer to reflect the amount of unprocessed data it currently holds.
if (bytes > 0) {
st_length_set(con->network.buffer, st_length_get(con->network.buffer) + bytes);
}
else if (bytes == 0) {
usleep(1000);
}
else {
con->network.status = -1;
return -1;
}
// Check whether we have a complete line before checking whether the connection was closed.
if (!st_empty(con->network.buffer) && !pl_empty((con->network.line = line_pl_st(con->network.buffer, 0)))) {
line = true;
}
} while (!line && block && counter++ < 128 && st_length_get(con->network.buffer) != st_avail_get(con->network.buffer) && status());
if (st_length_get(con->network.buffer) > 0) {
con->network.status = 1;
}
return pl_length_get(con->network.line);
}
/**
* @brief Read data from a network connection, and store the data in the connection context buffer.
* @note This function handles reading data from both regular and SSL connections.
* If the connection's network buffer hasn't been allocated, it will be initialized.
* @param con a pointer to the connection object from which the data will be read.
* @return -1 on general failure, -2 if the connection was reset, or the amount of data that was read.
*/
int64_t con_read(connection_t *con) {
ssize_t bytes = 0;
int_t counter = 0;
bool_t blocking = true;
if (!con || con->network.sockd == -1 || con_status(con) < 0) {
if (con) con->network.status = -1;
return -1;
}
// Check for an existing network buffer. If there isn't one, try creating it.
else if (!con->network.buffer && !con_init_network_buffer(con)) {
con->network.status = -1;
return -1;
}
// Check for data past the current line buffer.
else if (pl_length_get(con->network.line) && st_length_get(con->network.buffer) > pl_length_get(con->network.line)) {
// Move the unused data to the front of the buffer.
mm_move(st_data_get(con->network.buffer), st_data_get(con->network.buffer) + pl_length_get(con->network.line),
st_length_get(con->network.buffer) - pl_length_get(con->network.line));
// Update the length.
st_length_set(con->network.buffer, st_length_get(con->network.buffer) - pl_length_get(con->network.line));
// Clear the line buffer.
con->network.line = pl_null();
if (st_length_get(con->network.buffer)) {
return st_length_get(con->network.buffer);
}
}
// Otherwise reset the buffer and line lengths to zero.
else {
st_length_set(con->network.buffer, 0);
con->network.line = pl_null();
}
// Loop until the buffer has data or we get an error.
do {
// blocking = st_length_get(con->network.buffer) ? false : true;
blocking = true;
if (con->network.tls) {
bytes = tls_read(con->network.tls, st_char_get(con->network.buffer) + st_length_get(con->network.buffer),
st_avail_get(con->network.buffer) - st_length_get(con->network.buffer), blocking);
}
else {
bytes = tcp_read(con->network.sockd, st_char_get(con->network.buffer) + st_length_get(con->network.buffer),
st_avail_get(con->network.buffer) - st_length_get(con->network.buffer), blocking);
}
// We actually read in data, so we need to update the buffer to reflect the amount of unprocessed data it currently holds.
if (bytes > 0) {
st_length_set(con->network.buffer, st_length_get(con->network.buffer) + bytes);
}
else if (bytes == 0) {
usleep(1000);
}
else {
con->network.status = -1;
return -1;
}
} while (blocking && counter++ < 128 && !st_length_get(con->network.buffer) && status());
// If there is data in the buffer process it. Otherwise if the buffer is empty and the connection appears to be closed
// (as indicated by a return value of 0), then return -1 to let the caller know the connection is dead.
if (st_length_get(con->network.buffer)) {
con->network.status = 1;
}
return st_length_get(con->network.buffer);
}
