ClickHouse/base/common/ReplxxLineReader.cpp
2020-12-21 14:43:06 +08:00

249 lines
7.5 KiB
C++

#include <common/ReplxxLineReader.h>
#include <common/errnoToString.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <functional>
#include <sys/file.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <csignal>
#include <dlfcn.h>
#include <fcntl.h>
#include <fstream>
namespace
{
/// Trim ending whitespace inplace
void trim(String & s)
{
s.erase(std::find_if(s.rbegin(), s.rend(), [](int ch) { return !std::isspace(ch); }).base(), s.end());
}
}
ReplxxLineReader::ReplxxLineReader(
const Suggest & suggest,
const String & history_file_path_,
bool multiline_,
Patterns extenders_,
Patterns delimiters_,
replxx::Replxx::highlighter_callback_t highlighter_)
: LineReader(history_file_path_, multiline_, std::move(extenders_), std::move(delimiters_)), highlighter(std::move(highlighter_))
{
using namespace std::placeholders;
using Replxx = replxx::Replxx;
if (!history_file_path.empty())
{
history_file_fd = open(history_file_path.c_str(), O_RDWR);
if (history_file_fd < 0)
{
rx.print("Open of history file failed: %s\n", errnoToString(errno).c_str());
}
else
{
if (flock(history_file_fd, LOCK_SH))
{
rx.print("Shared lock of history file failed: %s\n", errnoToString(errno).c_str());
}
else
{
if (!rx.history_load(history_file_path))
{
rx.print("Loading history failed: %s\n", errnoToString(errno).c_str());
}
if (flock(history_file_fd, LOCK_UN))
{
rx.print("Unlock of history file failed: %s\n", errnoToString(errno).c_str());
}
}
}
}
rx.install_window_change_handler();
auto callback = [&suggest] (const String & context, size_t context_size)
{
if (auto range = suggest.getCompletions(context, context_size))
return Replxx::completions_t(range->first, range->second);
return Replxx::completions_t();
};
rx.set_completion_callback(callback);
rx.set_complete_on_empty(false);
rx.set_word_break_characters(word_break_characters);
if (highlighter)
rx.set_highlighter_callback(highlighter);
/// By default C-p/C-n binded to COMPLETE_NEXT/COMPLETE_PREV,
/// bind C-p/C-n to history-previous/history-next like readline.
rx.bind_key(Replxx::KEY::control('N'), [this](char32_t code) { return rx.invoke(Replxx::ACTION::HISTORY_NEXT, code); });
rx.bind_key(Replxx::KEY::control('P'), [this](char32_t code) { return rx.invoke(Replxx::ACTION::HISTORY_PREVIOUS, code); });
/// By default COMPLETE_NEXT/COMPLETE_PREV was binded to C-p/C-n, re-bind
/// to M-P/M-N (that was used for HISTORY_COMMON_PREFIX_SEARCH before, but
/// it also binded to M-p/M-n).
rx.bind_key(Replxx::KEY::meta('N'), [this](char32_t code) { return rx.invoke(Replxx::ACTION::COMPLETE_NEXT, code); });
rx.bind_key(Replxx::KEY::meta('P'), [this](char32_t code) { return rx.invoke(Replxx::ACTION::COMPLETE_PREVIOUS, code); });
rx.bind_key(Replxx::KEY::meta('E'), [this](char32_t) { openEditor(); return Replxx::ACTION_RESULT::CONTINUE; });
}
ReplxxLineReader::~ReplxxLineReader()
{
if (close(history_file_fd))
rx.print("Close of history file failed: %s\n", errnoToString(errno).c_str());
}
LineReader::InputStatus ReplxxLineReader::readOneLine(const String & prompt)
{
input.clear();
const char* cinput = rx.input(prompt);
if (cinput == nullptr)
return (errno != EAGAIN) ? ABORT : RESET_LINE;
input = cinput;
trim(input);
return INPUT_LINE;
}
void ReplxxLineReader::addToHistory(const String & line)
{
// locking history file to prevent from inconsistent concurrent changes
//
// replxx::Replxx::history_save() already has lockf(),
// but replxx::Replxx::history_load() does not
// and that is why flock() is added here.
bool locked = false;
if (flock(history_file_fd, LOCK_EX))
rx.print("Lock of history file failed: %s\n", errnoToString(errno).c_str());
else
locked = true;
rx.history_add(line);
// flush changes to the disk
if (!rx.history_save(history_file_path))
rx.print("Saving history failed: %s\n", errnoToString(errno).c_str());
if (locked && 0 != flock(history_file_fd, LOCK_UN))
rx.print("Unlock of history file failed: %s\n", errnoToString(errno).c_str());
}
int ReplxxLineReader::execute(const std::string & command)
{
std::vector<char> argv0("sh", &("sh"[3]));
std::vector<char> argv1("-c", &("-c"[3]));
std::vector<char> argv2(command.data(), command.data() + command.size() + 1);
const char * filename = "/bin/sh";
char * const argv[] = {argv0.data(), argv1.data(), argv2.data(), nullptr};
static void * real_vfork = dlsym(RTLD_DEFAULT, "vfork");
if (!real_vfork)
{
rx.print("Cannot find symbol vfork in myself: %s\n", errnoToString(errno).c_str());
return -1;
}
pid_t pid = reinterpret_cast<pid_t (*)()>(real_vfork)();
if (-1 == pid)
{
rx.print("Cannot vfork: %s\n", errnoToString(errno).c_str());
return -1;
}
if (0 == pid)
{
sigset_t mask;
sigemptyset(&mask);
sigprocmask(0, nullptr, &mask);
sigprocmask(SIG_UNBLOCK, &mask, nullptr);
execv(filename, argv);
_exit(-1);
}
int status = 0;
if (-1 == waitpid(pid, &status, 0))
{
rx.print("Cannot waitpid: %s\n", errnoToString(errno).c_str());
return -1;
}
return status;
}
void ReplxxLineReader::openEditor()
{
char filename[] = "clickhouse_replxx_XXXXXX.sql";
int fd = ::mkstemps(filename, 4);
if (-1 == fd)
{
rx.print("Cannot create temporary file to edit query: %s\n", errnoToString(errno).c_str());
return;
}
String editor = std::getenv("EDITOR");
if (editor.empty())
editor = "vim";
replxx::Replxx::State state(rx.get_state());
size_t bytes_written = 0;
const char * begin = state.text();
size_t offset = strlen(state.text());
while (bytes_written != offset)
{
ssize_t res = ::write(fd, begin + bytes_written, offset - bytes_written);
if ((-1 == res || 0 == res) && errno != EINTR)
{
rx.print("Cannot write to temporary query file %s: %s\n", filename, errnoToString(errno).c_str());
return;
}
bytes_written += res;
}
if (0 != ::close(fd))
{
rx.print("Cannot close temporary query file %s: %s\n", filename, errnoToString(errno).c_str());
return;
}
if (0 == execute(editor + " " + filename))
{
try
{
std::ifstream t(filename);
std::string str;
t.seekg(0, std::ios::end);
str.reserve(t.tellg());
t.seekg(0, std::ios::beg);
str.assign((std::istreambuf_iterator<char>(t)), std::istreambuf_iterator<char>());
rx.set_state(replxx::Replxx::State(str.c_str(), str.size()));
}
catch (...)
{
rx.print("Cannot read from temporary query file %s: %s\n", filename, errnoToString(errno).c_str());
return;
}
}
if (bracketed_paste_enabled)
enableBracketedPaste();
if (0 != ::unlink(filename))
rx.print("Cannot remove temporary query file %s: %s\n", filename, errnoToString(errno).c_str());
}
void ReplxxLineReader::enableBracketedPaste()
{
bracketed_paste_enabled = true;
rx.enable_bracketed_paste();
};