include/history.h

/*
 * *****************************************************************************
 *
 * Copyright (c) 2018-2020 Gavin D. Howard and contributors.
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * * Redistributions of source code must retain the above copyright notice, this
 *   list of conditions and the following disclaimer.
 *
 * * Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * *****************************************************************************
 *
 * Adapted from the following:
 *
 * linenoise.c -- guerrilla line editing library against the idea that a
 * line editing lib needs to be 20,000 lines of C code.
 *
 * You can find the original source code at:
 *   http://github.com/antirez/linenoise
 *
 * You can find the fork that this code is based on at:
 *   https://github.com/rain-1/linenoise-mob
 *
 * ------------------------------------------------------------------------
 *
 * This code is also under the following license:
 *
 * Copyright (c) 2010-2016, Salvatore Sanfilippo <antirez at gmail dot com>
 * Copyright (c) 2010-2013, Pieter Noordhuis <pcnoordhuis at gmail dot com>
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *  *  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *  *  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * *****************************************************************************
 *
 * Definitions for line history.
 *
 */

#ifndef BC_HISTORY_H
#define BC_HISTORY_H

#ifndef BC_ENABLE_HISTORY
#define BC_ENABLE_HISTORY (1)
#endif // BC_ENABLE_HISTORY

#if BC_ENABLE_HISTORY

#ifdef _WIN32
#error History is not supported on Windows.
#endif

#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>

#include <signal.h>

#include <termios.h>
#include <time.h>
#include <unistd.h>
#include <sys/select.h>

#include <status.h>
#include <vector.h>
#include <read.h>

#define BC_HIST_DEF_COLS (80)
#define BC_HIST_MAX_LEN (128)
#define BC_HIST_MAX_LINE (4095)
#define BC_HIST_SEQ_SIZE (64)

#define BC_HIST_BUF_LEN(h) ((h)->buf.len - 1)
#define BC_HIST_WRITE(s, n) (write(STDERR_FILENO, (s), (n)) != (ssize_t) (n))
#define BC_HIST_READ(s, n) (read(STDIN_FILENO, (s), (n)) == -1)

#define BC_HIST_NEXT (false)
#define BC_HIST_PREV (true)

#if BC_DEBUG_CODE
#define lndebug(...)                                               \
	do {                                                           \
		if (bc_history_debug_fp == NULL) {                         \
			bc_history_debug_fp = fopen("/tmp/lndebug.txt","a");   \
			fprintf(bc_history_debug_fp,                           \
			       "[%zu %zu %zu] p: %d, rows: %d, "               \
			       "rpos: %d, max: %zu, oldmax: %d\n",             \
			       l->len, l->pos, l->oldcolpos, plen, rows, rpos, \
			       l->maxrows, old_rows);                          \
		}                                                          \
		fprintf(bc_history_debug_fp, ", " __VA_ARGS__);            \
		fflush(bc_history_debug_fp);                               \
	} while (0)
#else // BC_DEBUG_CODE
#define lndebug(fmt, ...)
#endif // BC_DEBUG_CODE

#if !BC_ENABLE_PROMPT
#define bc_history_line(h, vec, prompt) bc_history_line(h, vec)
#define bc_history_raw(h, prompt) bc_history_raw(h)
#define bc_history_edit(h, prompt) bc_history_edit(h)
#endif // BC_ENABLE_PROMPT

typedef enum BcHistoryAction {

	BC_ACTION_NULL = 0,
	BC_ACTION_CTRL_A = 1,
	BC_ACTION_CTRL_B = 2,
	BC_ACTION_CTRL_C = 3,
	BC_ACTION_CTRL_D = 4,
	BC_ACTION_CTRL_E = 5,
	BC_ACTION_CTRL_F = 6,
	BC_ACTION_CTRL_H = 8,
	BC_ACTION_TAB = 9,
	BC_ACTION_LINE_FEED = 10,
	BC_ACTION_CTRL_K = 11,
	BC_ACTION_CTRL_L = 12,
	BC_ACTION_ENTER = 13,
	BC_ACTION_CTRL_N = 14,
	BC_ACTION_CTRL_P = 16,
	BC_ACTION_CTRL_T = 20,
	BC_ACTION_CTRL_U = 21,
	BC_ACTION_CTRL_W = 23,
	BC_ACTION_CTRL_Z = 26,
	BC_ACTION_ESC = 27,
	BC_ACTION_BACKSPACE =  127

} BcHistoryAction;

/**
 * This represents the state during line editing. We pass this state
 * to functions implementing specific editing functionalities.
 */
typedef struct BcHistory {

	/// Edited line buffer.
	BcVec buf;

	/// The history.
	BcVec history;

	/// A temporary buffer for refresh. Using this
	/// prevents an allocation on every refresh.
	BcVec tmp;

#if BC_ENABLE_PROMPT
	/// Prompt to display.
	const char *prompt;

	/// Prompt length.
	size_t plen;
#endif // BC_ENABLE_PROMPT

	/// Prompt column length.
	size_t pcol;

	/// Current cursor position.
	size_t pos;

	/// Previous refresh cursor column position.
	size_t oldcolpos;

	/// Number of columns in terminal.
	size_t cols;

	/// The history index we are currently editing.
	size_t idx;

	/// The original terminal state.
	struct termios orig_termios;

	/// This is to check if stdin has more data.
	fd_set rdset;

	/// This is to check if stdin has more data.
	struct timespec ts;

	/// This is to check if stdin has more data.
	sigset_t sigmask;

	/// This is to signal that there is more, so we don't process yet.
	bool stdin_has_data;

	/// Whether we are in rawmode.
	bool rawMode;

	/// Whether the terminal is bad.
	bool badTerm;

} BcHistory;

BcStatus bc_history_line(BcHistory *h, BcVec *vec, const char *prompt);
void bc_history_add(BcHistory *h, char *line);

void bc_history_init(BcHistory *h);
void bc_history_free(BcHistory *h);

extern const char *bc_history_bad_terms[];
extern const char bc_history_tab[];
extern const size_t bc_history_tab_len;
extern const char bc_history_ctrlc[];
extern const uint32_t bc_history_wchars[][2];
extern const size_t bc_history_wchars_len;
extern const uint32_t bc_history_combo_chars[];
extern const size_t bc_history_combo_chars_len;
#if BC_DEBUG_CODE
extern FILE *bc_history_debug_fp;
BcStatus bc_history_printKeyCodes(BcHistory* l);
#endif // BC_DEBUG_CODE

#endif // BC_ENABLE_HISTORY

#endif // BC_HISTORY_H