ardupilot/libraries/AP_HAL_PX4/NSHShellStream.cpp

144 lines
3.0 KiB
C++

/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
/*
implementation of NSH shell as a stream, for use in nsh over MAVLink
See GCS_serial_control.cpp for usage
*/
#include <AP_HAL/AP_HAL.h>
#if CONFIG_HAL_BOARD == HAL_BOARD_PX4
#include <stdio.h>
#include <stdarg.h>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include <apps/nsh.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include "Scheduler.h"
extern const AP_HAL::HAL& hal;
#include "Util.h"
using namespace PX4;
void NSHShellStream::shell_thread(void *arg)
{
NSHShellStream *nsh = (NSHShellStream *)arg;
close(0);
close(1);
close(2);
dup2(nsh->child.in, 0);
dup2(nsh->child.out, 1);
dup2(nsh->child.out, 2);
nsh_consolemain(0, NULL);
nsh->shell_stdin = -1;
nsh->shell_stdout = -1;
nsh->child.in = -1;
nsh->child.out = -1;
}
void NSHShellStream::start_shell(void)
{
if (hal.util->available_memory() < 8192) {
if (!showed_memory_warning) {
showed_memory_warning = true;
hal.console->printf("Not enough memory for shell\n");
}
return;
}
if (hal.util->get_soft_armed()) {
if (!showed_armed_warning) {
showed_armed_warning = true;
hal.console->printf("Disarm to start nsh shell\n");
}
// don't allow shell start when armed
return;
}
int p1[2], p2[2];
if (pipe(p1) != 0) {
return;
}
if (pipe(p2) != 0) {
return;
}
shell_stdin = p1[0];
shell_stdout = p2[1];
child.in = p2[0];
child.out = p1[1];
pthread_attr_t thread_attr;
struct sched_param param;
pthread_attr_init(&thread_attr);
pthread_attr_setstacksize(&thread_attr, 2048);
param.sched_priority = APM_SHELL_PRIORITY;
(void)pthread_attr_setschedparam(&thread_attr, &param);
pthread_attr_setschedpolicy(&thread_attr, SCHED_FIFO);
pthread_create(&shell_thread_ctx, &thread_attr, (pthread_startroutine_t)&PX4::NSHShellStream::shell_thread, this);
}
size_t NSHShellStream::write(uint8_t b)
{
if (shell_stdout == -1) {
start_shell();
}
if (shell_stdout != -1) {
return ::write(shell_stdout, &b, 1);
}
return 0;
}
size_t NSHShellStream::write(const uint8_t *buffer, size_t size)
{
size_t ret = 0;
while (size > 0) {
if (write(*buffer++) != 1) {
break;
}
ret++;
size--;
}
return ret;
}
int16_t NSHShellStream::read()
{
if (shell_stdin == -1) {
start_shell();
}
if (shell_stdin != -1) {
uint8_t b;
if (::read(shell_stdin, &b, 1) == 1) {
return b;
}
}
return -1;
}
int16_t NSHShellStream::available()
{
int ret = 0;
if (ioctl(shell_stdin, FIONREAD, (unsigned long)&ret) == OK) {
return ret;
}
return 0;
}
int16_t NSHShellStream::txspace()
{
int ret = 0;
if (ioctl(shell_stdout, FIONWRITE, (unsigned long)&ret) == OK) {
return ret;
}
return 0;
}
#endif // CONFIG_HAL_BOARD