void check_mark_easy(void)
{
qio_file_t* f;
qio_channel_t* writing;
qio_channel_t* reading;
int64_t offset;
err_t err;
err = qio_file_open_tmp(&f, 0, NULL);
assert(!err);
err = qio_channel_create(&writing, f, 0, 0, 1, 0, INT64_MAX, NULL);
assert(!err);
err = qio_channel_offset(true, writing, &offset);
assert(!err);
assert(offset == 0);
err = qio_channel_write_byte(true, writing, 'a');
assert(!err);
err = qio_channel_offset(true, writing, &offset);
assert(!err);
assert(offset == 1);
err = qio_channel_mark(true, writing);
assert(!err);
err = qio_channel_write_byte(true, writing, 'b');
assert(!err);
err = qio_channel_offset(true, writing, &offset);
assert(!err);
assert(offset == 2);
err = qio_channel_revert(true, writing);
assert(!err);
err = qio_channel_offset(true, writing, &offset);
assert(!err);
assert(offset == 1);
err = qio_channel_mark(true, writing);
assert(!err);
err = qio_channel_write_byte(true, writing, 'c');
assert(!err);
err = qio_channel_offset(true, writing, &offset);
assert(!err);
assert(offset == 2);
err = qio_channel_commit(true, writing);
assert(!err);
assert(offset == 2);
qio_channel_release(writing);
// Read the data a byte at a time.
err = qio_channel_create(&reading, f, 0, 1, 0, 0, INT64_MAX, NULL);
assert(!err);
assert('a' == qio_channel_read_byte(true, reading));
assert('c' == qio_channel_read_byte(true, reading));
assert(-EEOF == qio_channel_read_byte(true, reading));
qio_channel_release(reading);
// Close the file.
qio_file_release(f);
}
void check_mark(char* writepattern, char* readpattern)
{
qio_file_t* f;
qio_channel_t* writing;
qio_channel_t* reading;
int64_t offset;
int32_t got;
err_t err;
int i;
err = qio_file_open_tmp(&f, 0, NULL);
assert(!err);
err = qio_channel_create(&writing, f, 0, 0, 1, 0, INT64_MAX, NULL);
assert(!err);
err = qio_channel_offset(true, writing, &offset);
assert(!err);
assert(offset == 0);
for( i = 0; writepattern[i]; i++ ) {
switch (writepattern[i]) {
case 'M':
err = qio_channel_mark(true, writing);
break;
case 'R':
err = qio_channel_revert(true, writing);
break;
case 'C':
err = qio_channel_commit(true, writing);
break;
case 'A':
err = qio_channel_advance(true, writing, 1);
break;
default:
err = qio_channel_write_byte(true, writing, writepattern[i]);
}
assert(!err);
}
qio_channel_release(writing);
// Read the data a byte at a time.
err = qio_channel_create(&reading, f, 0, 1, 0, 0, INT64_MAX, NULL);
assert(!err);
for( i = 0; readpattern[i]; i++ ) {
switch (readpattern[i]) {
case 'M':
err = qio_channel_mark(true, reading);
break;
case 'R':
err = qio_channel_revert(true, reading);
break;
case 'C':
err = qio_channel_commit(true, reading);
break;
case 'A':
err = qio_channel_advance(true, reading, 1);
break;
default:
got = qio_channel_read_byte(true, reading);
if( got >= 0 ) assert(got == readpattern[i]);
else err = -got;
}
assert(!err);
}
got = qio_channel_read_byte(true, reading);
assert( got == - EEOF );
qio_channel_release(reading);
// Close the file.
qio_file_release(f);
}
// commit input, sending any data to the subprocess.
// once input is sent, close input channel and file.
// While sending that data, read output and error channels,
// buffering up the read data.
// once output/error reads EOF, close output/error file (not channel
// since output channel has the buffered data).
qioerr qio_proc_communicate(
const int threadsafe,
qio_channel_t* input,
qio_channel_t* output,
qio_channel_t* error) {
qioerr err = 0;
int rc = 0;
bool do_input;
bool do_output;
bool do_error;
bool input_ready;
bool output_ready;
bool error_ready;
fd_set rfds, wfds, efds;
int nfds = 1;
int input_fd = -1;
int output_fd = -1;
int error_fd = -1;
if( threadsafe ) {
// lock all three channels.
// but unlock them immediately and set them to NULL
// if they are already closed.
if( input ) {
err = qio_lock(&input->lock);
if( err ) return err;
if( qio_channel_isclosed(false, input) ) {
qio_unlock(&input->lock);
input = NULL;
}
}
if( output ) {
err = qio_lock(&output->lock);
if( err ) {
if( input ) qio_unlock(&input->lock);
return err;
}
if( qio_channel_isclosed(false, output) ) {
qio_unlock(&output->lock);
output = NULL;
}
}
if( error ) {
err = qio_lock(&error->lock);
if( err ) {
if( input ) qio_unlock(&input->lock);
if( output ) qio_unlock(&output->lock);
return err;
}
if( qio_channel_isclosed(false, error) ) {
qio_unlock(&error->lock);
error = NULL;
}
}
}
if( input ) {
input_fd = input->file->fd;
if( nfds <= input_fd ) nfds = input_fd + 1;
}
if( output ) {
output_fd = output->file->fd;
if( nfds <= output_fd ) nfds = output_fd + 1;
}
if( error ) {
error_fd = error->file->fd;
if( nfds <= error_fd ) nfds = error_fd + 1;
}
// Adjust all three pipes to be non-blocking.
if( input_fd != -1 ) {
rc = fcntl(input_fd, F_SETFL, O_NONBLOCK);
if( rc == -1 ) {
err = qio_int_to_err(errno);
}
}
if( output_fd != -1 ) {
rc = fcntl(output_fd, F_SETFL, O_NONBLOCK);
if( rc == -1 ) {
err = qio_int_to_err(errno);
}
}
if( error_fd != -1 ) {
rc = fcntl(error_fd, F_SETFL, O_NONBLOCK);
if( rc == -1 ) {
err = qio_int_to_err(errno);
}
}
// mark the output and error channels so that we
// can just keep advancing to read while buffering
// up all data. Before returning, we'll revert them
// so that this buffered data can be read again and
// update end_pos so that the channel knows not to
// call read again. Then, we can close the file
// descriptor.
if( output ) {
qio_channel_mark(false, output);
}
if( error ) {
qio_channel_mark(false, error);
}
do_input = (input != NULL);
do_output = (output != NULL);
do_error = (error != NULL);
while( do_input || do_output || do_error ) {
// Now call select to wait for one of the descriptors to
// become ready.
FD_ZERO(&rfds);
FD_ZERO(&wfds);
FD_ZERO(&efds);
if( do_input && input_fd != -1 ) {
FD_SET(input_fd, &wfds);
FD_SET(input_fd, &efds);
}
if( do_output && output_fd != -1 ) {
FD_SET(output_fd, &rfds);
FD_SET(output_fd, &efds);
}
if( do_error && error_fd != -1 ) {
FD_SET(error_fd, &rfds);
FD_SET(error_fd, &efds);
}
input_ready = false;
output_ready = false;
error_ready = false;
// Run select to wait for something
if( do_input || do_output || do_error ) {
// TODO -- use sys_select so threading can interact
struct timeval t;
t.tv_sec = 0;
t.tv_usec = 10;
rc = select(nfds, &rfds, &wfds, &efds, &t);
if (rc > 0) {
// read ready file descriptors
input_ready = input_fd != -1 && FD_ISSET(input_fd, &wfds);
output_ready = output_fd != -1 && FD_ISSET(output_fd, &rfds);
error_ready = error_fd != -1 && FD_ISSET(error_fd, &rfds);
}
// Ignore EAGAIN and EINTR
if (rc == EAGAIN || rc == EINTR) rc = 0;
}
if( rc == -1 ) {
err = qio_int_to_err(errno);
break;
}
if( do_input && input_ready ) {
err = _qio_channel_flush_qio_unlocked(input);
if( !err ) {
do_input = false;
// Close input channel.
err = qio_channel_close(false, input);
}
if( qio_err_to_int(err) == EAGAIN ) err = 0;
if( err ) break;
}
if( do_output && output_ready ) {
// read some into our buffer.
err = qio_channel_advance(false, output, qbytes_iobuf_size);
if( qio_err_to_int(err) == EEOF ) {
qio_file_t* output_file = qio_channel_get_file(output);
do_output = false;
// close the output file (not channel), in case closing output
// causes the program to output on stderr, e.g.
if( output_file )
err = qio_file_close(output_file);
// Set the output channel maximum position
// This prevents a read on output from trying to get
// more data from the (now closed) file.
output->end_pos = qio_channel_offset_unlocked(output);
}
if( qio_err_to_int(err) == EAGAIN ) err = 0;
if( err ) break;
}
if( do_error && error_ready ) {
// read some into our buffer.
err = qio_channel_advance(false, error, qbytes_iobuf_size);
if( qio_err_to_int(err) == EEOF ) {
qio_file_t* error_file = qio_channel_get_file(error);
do_error = false;
// close the error file (not channel)
if( error_file )
err = qio_file_close(error_file);
// Set the error channel maximum position
error->end_pos = qio_channel_offset_unlocked(error);
}
if( qio_err_to_int(err) == EAGAIN ) err = 0;
if( err ) break;
}
chpl_task_yield();
}
// we could close the file descriptors at this point,
// but we don't because we don't want to modify
// the file descriptor of the file since it's
// constant (and not protected by file's lock).
// The pipes will be closed when the channels are destroyed.
// We marked the output and error channels so that we
// can just keep advancing to read while buffering
// up all data. Before returning, we'll revert them
// so that this buffered data can be read again and
// update end_pos so that the channel knows not to
// call read again. Then, we can close the file
// descriptor.
// revert the output and error channels
if( output) qio_channel_revert_unlocked(output);
if( error ) qio_channel_revert_unlocked(error);
if( threadsafe ) {
// unlock all three channels.
if( error ) qio_unlock(&error->lock);
if( output ) qio_unlock(&output->lock);
if( input ) qio_unlock(&input->lock);
}
return err;
}