ladybird/Shell/LineEditor.cpp
Andreas Kling 6f4c380d95 AK: Use size_t for the length of strings
Using int was a mistake. This patch changes String, StringImpl,
StringView and StringBuilder to use size_t instead of int for lengths.
Obviously a lot of code needs to change as a result of this.
2019-12-09 17:51:21 +01:00

373 lines
12 KiB
C++

#include "LineEditor.h"
#include "GlobalState.h"
#include <ctype.h>
#include <stdio.h>
#include <unistd.h>
LineEditor::LineEditor()
{
}
LineEditor::~LineEditor()
{
}
void LineEditor::add_to_history(const String& line)
{
if ((m_history.size() + 1) > m_history_capacity)
m_history.take_first();
m_history.append(line);
}
void LineEditor::clear_line()
{
for (size_t i = 0; i < m_cursor; ++i)
fputc(0x8, stdout);
fputs("\033[K", stdout);
fflush(stdout);
m_buffer.clear();
m_cursor = 0;
}
void LineEditor::append(const String& string)
{
m_buffer.append(string.characters(), (int)string.length());
fputs(string.characters(), stdout);
fflush(stdout);
m_cursor = (size_t)m_buffer.size();
}
void LineEditor::cache_path()
{
if (!m_path.is_empty())
m_path.clear_with_capacity();
String path = getenv("PATH");
if (path.is_empty())
return;
auto directories = path.split(':');
for (const auto& directory : directories) {
CDirIterator programs(directory.characters(), CDirIterator::SkipDots);
while (programs.has_next()) {
auto program = programs.next_path();
StringBuilder program_path;
program_path.append(directory.characters());
program_path.append('/');
program_path.append(program.characters());
struct stat program_status;
int stat_error = stat(program_path.to_string().characters(), &program_status);
if (stat_error || !(program_status.st_mode & S_IXUSR))
continue;
m_path.append(program.characters());
}
}
quick_sort(m_path.begin(), m_path.end(), AK::is_less_than<String>);
}
void LineEditor::cut_mismatching_chars(String& completion, const String& program, size_t token_length)
{
size_t i = token_length;
while (i < completion.length() && i < program.length() && completion[i] == program[i])
++i;
completion = completion.substring(0, i);
}
void LineEditor::tab_complete_first_token()
{
String token = String::copy(m_buffer);
auto match = binary_search(m_path.data(), m_path.size(), token, [](const String& token, const String& program) -> int {
return strncmp(token.characters(), program.characters(), token.length());
});
if (!match)
return;
String completion = *match;
// Now that we have a program name starting with our token, we look at
// other program names starting with our token and cut off any mismatching
// characters.
int index = match - m_path.data();
for (int i = index - 1; i >= 0 && m_path[i].starts_with(token); --i)
cut_mismatching_chars(completion, m_path[i], token.length());
for (int i = index + 1; i < m_path.size() && m_path[i].starts_with(token); ++i)
cut_mismatching_chars(completion, m_path[i], token.length());
if (token.length() == completion.length())
return;
append(completion.substring(token.length(), completion.length() - token.length()).characters());
}
String LineEditor::get_line(const String& prompt)
{
fputs(prompt.characters(), stdout);
fflush(stdout);
m_history_cursor = m_history.size();
m_cursor = 0;
for (;;) {
char keybuf[16];
ssize_t nread = read(0, keybuf, sizeof(keybuf));
// FIXME: exit()ing here is a bit off. Should communicate failure to caller somehow instead.
if (nread == 0)
exit(0);
if (nread < 0) {
if (errno == EINTR) {
if (g.was_interrupted) {
g.was_interrupted = false;
if (!m_buffer.is_empty())
printf("^C");
}
if (g.was_resized) {
g.was_resized = false;
printf("\033[2K\r");
m_buffer.clear();
return String::empty();
}
m_buffer.clear();
putchar('\n');
return String::empty();
}
perror("read failed");
// FIXME: exit()ing here is a bit off. Should communicate failure to caller somehow instead.
exit(2);
}
auto do_delete = [&] {
if (m_cursor == (size_t)m_buffer.size()) {
fputc('\a', stdout);
fflush(stdout);
return;
}
m_buffer.remove((int)m_cursor - 1);
fputs("\033[3~", stdout);
fflush(stdout);
vt_save_cursor();
vt_clear_to_end_of_line();
for (size_t i = m_cursor; i < (size_t)m_buffer.size(); ++i)
fputc(m_buffer[i], stdout);
vt_restore_cursor();
};
for (ssize_t i = 0; i < nread; ++i) {
char ch = keybuf[i];
if (ch == 0)
continue;
switch (m_state) {
case InputState::ExpectBracket:
if (ch == '[') {
m_state = InputState::ExpectFinal;
continue;
} else {
m_state = InputState::Free;
break;
}
case InputState::ExpectFinal:
switch (ch) {
case 'A': // up
if (m_history_cursor > 0)
--m_history_cursor;
clear_line();
if (m_history_cursor < m_history.size())
append(m_history[m_history_cursor]);
m_state = InputState::Free;
continue;
case 'B': // down
if (m_history_cursor < m_history.size())
++m_history_cursor;
clear_line();
if (m_history_cursor < m_history.size())
append(m_history[m_history_cursor]);
m_state = InputState::Free;
continue;
case 'D': // left
if (m_cursor > 0) {
--m_cursor;
fputs("\033[D", stdout);
fflush(stdout);
}
m_state = InputState::Free;
continue;
case 'C': // right
if (m_cursor < (size_t)m_buffer.size()) {
++m_cursor;
fputs("\033[C", stdout);
fflush(stdout);
}
m_state = InputState::Free;
continue;
case 'H':
if (m_cursor > 0) {
fprintf(stdout, "\033[%zuD", m_cursor);
fflush(stdout);
m_cursor = 0;
}
m_state = InputState::Free;
continue;
case 'F':
if (m_cursor < (size_t)m_buffer.size()) {
fprintf(stdout, "\033[%zuC", (size_t)m_buffer.size() - m_cursor);
fflush(stdout);
m_cursor = (size_t)m_buffer.size();
}
m_state = InputState::Free;
continue;
case '3':
do_delete();
m_state = InputState::ExpectTerminator;
continue;
default:
dbgprintf("Shell: Unhandled final: %b (%c)\n", ch, ch);
m_state = InputState::Free;
continue;
}
break;
case InputState::ExpectTerminator:
m_state = InputState::Free;
continue;
case InputState::Free:
if (ch == 27) {
m_state = InputState::ExpectBracket;
continue;
}
break;
}
if (ch == '\t') {
if (m_buffer.is_empty())
continue;
bool is_first_token = true;
for (const auto& character : m_buffer) {
if (isspace(character)) {
is_first_token = false;
break;
}
}
// FIXME: Implement tab-completion for other tokens (paths).
if (is_first_token)
tab_complete_first_token();
continue;
}
auto do_backspace = [&] {
if (m_cursor == 0) {
fputc('\a', stdout);
fflush(stdout);
return;
}
m_buffer.remove((int)m_cursor - 1);
--m_cursor;
putchar(8);
vt_save_cursor();
vt_clear_to_end_of_line();
for (size_t i = m_cursor; i < (size_t)m_buffer.size(); ++i)
fputc(m_buffer[(int)i], stdout);
vt_restore_cursor();
};
if (ch == 8 || ch == g.termios.c_cc[VERASE]) {
do_backspace();
continue;
}
if (ch == g.termios.c_cc[VWERASE]) {
bool has_seen_nonspace = false;
while (m_cursor > 0) {
if (isspace(m_buffer[(int)m_cursor - 1])) {
if (has_seen_nonspace)
break;
} else {
has_seen_nonspace = true;
}
do_backspace();
}
continue;
}
if (ch == g.termios.c_cc[VKILL]) {
while (m_cursor > 0)
do_backspace();
continue;
}
if (ch == 0xc) { // ^L
printf("\033[3J\033[H\033[2J"); // Clear screen.
fputs(prompt.characters(), stdout);
for (int i = 0; i < m_buffer.size(); ++i)
fputc(m_buffer[i], stdout);
if (m_cursor < (size_t)m_buffer.size())
printf("\033[%zuD", (size_t)m_buffer.size() - m_cursor); // Move cursor N steps left.
fflush(stdout);
continue;
}
if (ch == 0x01) { // ^A
if (m_cursor > 0) {
printf("\033[%zuD", m_cursor);
fflush(stdout);
m_cursor = 0;
}
continue;
}
if (ch == g.termios.c_cc[VEOF]) { // Normally ^D
if (m_buffer.is_empty()) {
printf("<EOF>\n");
exit(0);
}
continue;
}
if (ch == 0x05) { // ^E
if (m_cursor < (size_t)m_buffer.size()) {
printf("\033[%zuC", (size_t)m_buffer.size() - m_cursor);
fflush(stdout);
m_cursor = (size_t)m_buffer.size();
}
continue;
}
putchar(ch);
fflush(stdout);
if (ch == '\n') {
auto string = String::copy(m_buffer);
m_buffer.clear();
return string;
}
if (m_cursor == (size_t)m_buffer.size()) {
m_buffer.append(ch);
++m_cursor;
continue;
}
vt_save_cursor();
vt_clear_to_end_of_line();
for (size_t i = m_cursor; i < (size_t)m_buffer.size(); ++i)
fputc(m_buffer[(int)i], stdout);
vt_restore_cursor();
m_buffer.insert((int)m_cursor, move(ch));
++m_cursor;
}
}
}
void LineEditor::vt_save_cursor()
{
fputs("\033[s", stdout);
fflush(stdout);
}
void LineEditor::vt_restore_cursor()
{
fputs("\033[u", stdout);
fflush(stdout);
}
void LineEditor::vt_clear_to_end_of_line()
{
fputs("\033[K", stdout);
fflush(stdout);
}