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Regard whitespace Rev 7412 → Rev 7413

/programs/other/tte/tte.c
0,0 → 1,1713
/*
* Copyright (C) 2017 Daniel Morales
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
 
/*** Include section ***/
 
// We add them above our includes, because the header
// files we are including use the macros to decide what
// features to expose. These macros remove some compilation
// warnings. See
// https://www.gnu.org/software/libc/manual/html_node/Feature-Test-Macros.html
// for more info.
#define _DEFAULT_SOURCE
#define _BSD_SOURCE
#define _GNU_SOURCE
 
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <termios.h>
#include <time.h>
#include <unistd.h>
 
/*** Define section ***/
 
// This mimics the Ctrl + whatever behavior, setting the
// 3 upper bits of the character pressed to 0.
#define CTRL_KEY(k) ((k) & 0x1f)
// Empty buffer
#define ABUF_INIT {NULL, 0}
// Version code
#define TTE_VERSION "0.0.5"
// Length of a tab stop
#define TTE_TAB_STOP 4
// Times to press Ctrl-Q before exiting
#define TTE_QUIT_TIMES 2
// Highlight flags
#define HL_HIGHLIGHT_NUMBERS (1 << 0)
#define HL_HIGHLIGHT_STRINGS (1 << 1)
 
/*** Data section ***/
 
typedef struct editor_row {
int idx; // Row own index within the file.
int size; // Size of the content (excluding NULL term)
int render_size; // Size of the rendered content
char* chars; // Row content
char* render; // Row content "rendered" for screen (for TABs).
unsigned char* highlight; // This will tell you if a character is part of a string, comment, number...
int hl_open_comment; // True if the line is part of a ML comment.
} editor_row;
 
struct editor_syntax {
// file_type field is the name of the filetype that will be displayed
// to the user in the status bar.
char* file_type;
// file_match is an array of strings, where each string contains a
// pattern to match a filename against. If the filename matches,
// then the file will be recognized as having that filetype.
char** file_match;
// This will be a NULL-terminated array of strings, each string containing
// a keyword. To differentiate between the two types of keywords,
// we’ll terminate the second type of keywords with a pipe (|)
// character (also known as a vertical bar).
char** keywords;
// We let each language specify its own single-line comment pattern.
char* singleline_comment_start;
// flags is a bit field that will contain flags for whether to
// highlight numbers and whether to highlight strings for that
// filetype.
char* multiline_comment_start;
char* multiline_comment_end;
int flags;
};
 
struct editor_config {
int cursor_x;
int cursor_y;
int render_x;
int row_offset; // Offset of row displayed.
int col_offset; // Offset of col displayed.
int screen_rows; // Number of rows that we can show
int screen_cols; // Number of cols that we can show
int num_rows; // Number of rows
editor_row* row;
int dirty; // To know if a file has been modified since opening.
char* file_name;
char status_msg[80];
time_t status_msg_time;
char* copied_char_buffer;
struct editor_syntax* syntax;
struct termios orig_termios;
} ec;
 
// Having a dynamic buffer will allow us to write only one
// time once the screen is refreshing, instead of doing
// a lot of write's.
struct a_buf {
char* buf;
int len;
};
 
enum editor_key {
BACKSPACE = 0x7f, // 127
ARROW_LEFT = 0x3e8, // 1000, large value out of the range of a char.
ARROW_RIGHT,
ARROW_UP,
ARROW_DOWN,
PAGE_UP,
PAGE_DOWN,
HOME_KEY,
END_KEY,
DEL_KEY
};
 
enum editor_highlight {
HL_NORMAL = 0,
HL_SL_COMMENT,
HL_ML_COMMENT,
HL_KEYWORD_1,
HL_KEYWORD_2,
HL_STRING,
HL_NUMBER,
HL_MATCH
};
 
/*** Filetypes ***/
 
char* C_HL_extensions[] = {".c", ".h", ".cpp", ".hpp", ".cc", NULL}; // Array must be terminated with NULL.
char* JAVA_HL_extensions[] = {".java", NULL};
char* PYTHON_HL_extensions[] = {".py", NULL};
char* BASH_HL_extensions[] = {".sh", NULL};
char* JS_HL_extensions[] = {".js", ".jsx", NULL};
char* PHP_HL_extensions[] = {".php", NULL};
char* JSON_HL_extensions[] = {".json", ".jsonp", NULL};
char* XML_HL_extensions[] = {".xml", NULL};
char* SQL_HL_extensions[] = {".sql", NULL};
char* RUBY_HL_extensions[] = {".rb", NULL};
 
char* C_HL_keywords[] = {
"switch", "if", "while", "for", "break", "continue", "return", "else",
"struct", "union", "typedef", "static", "enum", "class", "case", "#include",
"volatile", "register", "sizeof", "typedef", "union", "goto", "const", "auto",
"#define", "#if", "#endif", "#error", "#ifdef", "#ifndef", "#undef",
 
"int|", "long|", "double|", "float|", "char|", "unsigned|", "signed|",
"void|", "bool|", NULL
};
 
char* JAVA_HL_keywords[] = {
"switch", "if", "while", "for", "break", "continue", "return", "else",
"in", "public", "private", "protected", "static", "final", "abstract",
"enum", "class", "case", "try", "catch", "do", "extends", "implements",
"finally", "import", "instanceof", "interface", "new", "package", "super",
"native", "strictfp",
"synchronized", "this", "throw", "throws", "transient", "volatile",
 
"byte|", "char|", "double|", "float|", "int|", "long|", "short|",
"boolean|", NULL
};
 
char* PYTHON_HL_keywords[] = {
"and", "as", "assert", "break", "class", "continue", "def", "del", "elif",
"else", "except", "exec", "finally", "for", "from", "global", "if", "import",
"in", "is", "lambda", "not", "or", "pass", "print", "raise", "return", "try",
"while", "with", "yield",
 
"buffer|", "bytearray|", "complex|", "False|", "float|", "frozenset|", "int|",
"list|", "long|", "None|", "set|", "str|", "tuple|", "True|", "type|",
"unicode|", "xrange|", NULL
};
 
char* BASH_HL_keywords[] = {
"case", "do", "done", "elif", "else", "esac", "fi", "for", "function", "if",
"in", "select", "then", "time", "until", "while", "alias", "bg", "bind", "break",
"builtin", "cd", "command", "continue", "declare", "dirs", "disown", "echo",
"enable", "eval", "exec", "exit", "export", "fc", "fg", "getopts", "hash", "help",
"history", "jobs", "kill", "let", "local", "logout", "popd", "pushd", "pwd", "read",
"readonly", "return", "set", "shift", "suspend", "test", "times", "trap", "type",
"typeset", "ulimit", "umask", "unalias", "unset", "wait", "printf", NULL
};
 
char* JS_HL_keywords[] = {
"break", "case", "catch", "class", "const", "continue", "debugger", "default",
"delete", "do", "else", "enum", "export", "extends", "finally", "for", "function",
"if", "implements", "import", "in", "instanceof", "interface", "let", "new",
"package", "private", "protected", "public", "return", "static", "super", "switch",
"this", "throw", "try", "typeof", "var", "void", "while", "with", "yield", "true",
"false", "null", "NaN", "global", "window", "prototype", "constructor", "document",
"isNaN", "arguments", "undefined",
 
"Infinity|", "Array|", "Object|", "Number|", "String|", "Boolean|", "Function|",
"ArrayBuffer|", "DataView|", "Float32Array|", "Float64Array|", "Int8Array|",
"Int16Array|", "Int32Array|", "Uint8Array|", "Uint8ClampedArray|", "Uint32Array|",
"Date|", "Error|", "Map|", "RegExp|", "Symbol|", "WeakMap|", "WeakSet|", "Set|", NULL
};
 
char* PHP_HL_keywords[] = {
"__halt_compiler", "break", "clone", "die", "empty", "endswitch", "final", "global",
"include_once", "list", "private", "return", "try", "xor", "abstract", "callable",
"const", "do", "enddeclare", "endwhile", "finally", "goto", "instanceof", "namespace",
"protected", "static", "unset", "yield", "and", "case", "continue", "echo", "endfor",
"eval", "for", "if", "insteadof", "new", "public", "switch", "use", "array", "catch",
"declare", "else", "endforeach", "exit", "foreach", "implements", "interface", "or",
"require", "throw", "var", "as", "class", "default", "elseif", "endif", "extends",
"function", "include", "isset", "print", "require_once", "trait", "while", NULL
};
 
char* JSON_HL_keywords[] = {
NULL
};
 
char* XML_HL_keywords[] = {
NULL
};
 
char* SQL_HL_keywords[] = {
"SELECT", "FROM", "DROP", "CREATE", "TABLE", "DEFAULT", "FOREIGN", "UPDATE", "LOCK",
"INSERT", "INTO", "VALUES", "LOCK", "UNLOCK", "WHERE", "DINSTINCT", "BETWEEN", "NOT",
"NULL", "TO", "ON", "ORDER", "GROUP", "IF", "BY", "HAVING", "USING", "UNION", "UNIQUE",
"AUTO_INCREMENT", "LIKE", "WITH", "INNER", "OUTER", "JOIN", "COLUMN", "DATABASE", "EXISTS",
"NATURAL", "LIMIT", "UNSIGNED", "MAX", "MIN", "PRECISION", "ALTER", "DELETE", "CASCADE",
"PRIMARY", "KEY", "CONSTRAINT", "ENGINE", "CHARSET", "REFERENCES", "WRITE",
 
"BIT|", "TINYINT|", "BOOL|", "BOOLEAN|", "SMALLINT|", "MEDIUMINT|", "INT|", "INTEGER|",
"BIGINT|", "DOUBLE|", "DECIMAL|", "DEC|" "FLOAT|", "DATE|", "DATETIME|", "TIMESTAMP|",
"TIME|", "YEAR|", "CHAR|", "VARCHAR|", "TEXT|", "ENUM|", "SET|", "BLOB|", "VARBINARY|",
"TINYBLOB|", "TINYTEXT|", "MEDIUMBLOB|", "MEDIUMTEXT|", "LONGTEXT|",
 
"select", "from", "drop", "create", "table", "default", "foreign", "update", "lock",
"insert", "into", "values", "lock", "unlock", "where", "dinstinct", "between", "not",
"null", "to", "on", "order", "group", "if", "by", "having", "using", "union", "unique",
"auto_increment", "like", "with", "inner", "outer", "join", "column", "database", "exists",
"natural", "limit", "unsigned", "max", "min", "precision", "alter", "delete", "cascade",
"primary", "key", "constraint", "engine", "charset", "references", "write",
 
"bit|", "tinyint|", "bool|", "boolean|", "smallint|", "mediumint|", "int|", "integer|",
"bigint|", "double|", "decimal|", "dec|" "float|", "date|", "datetime|", "timestamp|",
"time|", "year|", "char|", "varchar|", "text|", "enum|", "set|", "blob|", "varbinary|",
"tinyblob|", "tinytext|", "mediumblob|", "mediumtext|", "longtext|", NULL
};
 
char* RUBY_HL_keywords[] = {
"__ENCODING__", "__LINE__", "__FILE__", "BEGIN", "END", "alias", "and", "begin", "break",
"case", "class", "def", "defined?", "do", "else", "elsif", "end", "ensure", "for", "if",
"in", "module", "next", "not", "or", "redo", "rescue", "retry", "return", "self", "super",
"then", "undef", "unless", "until", "when", "while", "yield", NULL
};
 
struct editor_syntax HL_DB[] = {
{
"c",
C_HL_extensions,
C_HL_keywords,
"//",
"/*",
"*/",
HL_HIGHLIGHT_NUMBERS | HL_HIGHLIGHT_STRINGS
},
{
"java",
JAVA_HL_extensions,
JAVA_HL_keywords,
"//",
"/*",
"*/",
HL_HIGHLIGHT_NUMBERS | HL_HIGHLIGHT_STRINGS
},
{
"python",
PYTHON_HL_extensions,
PYTHON_HL_keywords,
"#",
"'''",
"'''",
HL_HIGHLIGHT_NUMBERS | HL_HIGHLIGHT_STRINGS
},
{
"bash",
BASH_HL_extensions,
BASH_HL_keywords,
"#",
NULL,
NULL,
HL_HIGHLIGHT_NUMBERS | HL_HIGHLIGHT_STRINGS
},
{
"js",
JS_HL_extensions,
JS_HL_keywords,
"//",
"/*",
"*/",
HL_HIGHLIGHT_NUMBERS | HL_HIGHLIGHT_STRINGS
},
{
"php",
PHP_HL_extensions,
PHP_HL_keywords,
"//",
"/*",
"*/",
HL_HIGHLIGHT_NUMBERS | HL_HIGHLIGHT_STRINGS
},
{
"json",
JSON_HL_extensions,
JSON_HL_keywords,
NULL,
NULL,
NULL,
HL_HIGHLIGHT_NUMBERS | HL_HIGHLIGHT_STRINGS
},
{
"xml",
XML_HL_extensions,
XML_HL_keywords,
NULL,
NULL,
NULL,
HL_HIGHLIGHT_NUMBERS | HL_HIGHLIGHT_STRINGS
},
{
"sql",
SQL_HL_extensions,
SQL_HL_keywords,
"--",
"/*",
"*/",
HL_HIGHLIGHT_NUMBERS | HL_HIGHLIGHT_STRINGS
},
{
"ruby",
RUBY_HL_extensions,
RUBY_HL_keywords,
"#",
"=begin",
"=end",
HL_HIGHLIGHT_NUMBERS | HL_HIGHLIGHT_STRINGS
}
};
 
// Size of the "Hightlight Database" (HL_DB).
#define HL_DB_ENTRIES (sizeof(HL_DB) / sizeof(HL_DB[0]))
 
/*** Declarations section ***/
 
void editorClearScreen();
 
void editorRefreshScreen();
 
void editorSetStatusMessage(const char* msg, ...);
 
void consoleBufferOpen();
 
void abufFree();
 
void abufAppend();
 
char *editorPrompt(char* prompt, void (*callback)(char*, int));
 
void editorRowAppendString(editor_row* row, char* s, size_t len);
 
void editorInsertNewline();
 
/*** Terminal section ***/
 
void die(const char* s) {
editorClearScreen();
// perror looks for global errno variable and then prints
// a descriptive error mesage for it.
perror(s);
printf("\r\n");
exit(1);
}
 
void disableRawMode() {
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &ec.orig_termios) == -1)
die("Failed to disable raw mode");
}
 
void enableRawMode() {
// Save original terminal state into orig_termios.
if (tcgetattr(STDIN_FILENO, &ec.orig_termios) == -1)
die("Failed to get current terminal state");
// At exit, restore the original state.
atexit(disableRawMode);
 
// Modify the original state to enter in raw mode.
struct termios raw = ec.orig_termios;
// This disables Ctrl-M, Ctrl-S and Ctrl-Q commands.
// (BRKINT, INPCK and ISTRIP are not estrictly mandatory,
// but it is recommended to turn them off in case any
// system needs it).
raw.c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
// Turning off all output processing (\r\n).
raw.c_oflag &= ~(OPOST);
// Setting character size to 8 bits per byte (it should be
// like that on most systems, but whatever).
raw.c_cflag |= (CS8);
// Using NOT operator on ECHO | ICANON | IEXTEN | ISIG and
// then bitwise-AND them with flags field in order to
// force c_lflag 4th bit to become 0. This disables
// chars being printed (ECHO) and let us turn off
// canonical mode in order to read input byte-by-byte
// instead of line-by-line (ICANON), ISIG disables
// Ctrl-C command and IEXTEN the Ctrl-V one.
raw.c_lflag &= ~(ECHO | ICANON | IEXTEN | ISIG);
// read() function now returns as soon as there is any
// input to be read.
raw.c_cc[VMIN] = 0;
// Forcing read() function to return every 1/10 of a
// second if there is nothing to read.
raw.c_cc[VTIME] = 1;
 
consoleBufferOpen();
 
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &raw) == -1)
die("Failed to set raw mode");
}
 
int editorReadKey() {
int nread;
char c;
while ((nread = read(STDIN_FILENO, &c, 1)) != 1) {
// Ignoring EAGAIN to make it work on Cygwin.
if (nread == -1 && errno != EAGAIN)
die("Error reading input");
}
 
// Check escape sequences, if first byte
// is an escape character then...
if (c == '\x1b') {
char seq[3];
 
if (read(STDIN_FILENO, &seq[0], 1) != 1 ||
read(STDIN_FILENO, &seq[1], 1) != 1)
return '\x1b';
 
if (seq[0] == '[') {
if (seq[1] >= '0' && seq[1] <= '9') {
if (read(STDIN_FILENO, &seq[2], 1) != 1)
return '\x1b';
if (seq[2] == '~') {
switch (seq[1]) {
// Home and End keys may be sent in many ways depending on the OS
// \x1b[1~, \x1b[7~, \x1b[4~, \x1b[8~
case '1':
case '7':
return HOME_KEY;
case '4':
case '8':
return END_KEY;
// Del key is sent as \x1b[3~
case '3':
return DEL_KEY;
// Page Up and Page Down send '\x1b', '[', '5' or '6' and '~'.
case '5': return PAGE_UP;
case '6': return PAGE_DOWN;
}
}
} else {
switch (seq[1]) {
// Arrow keys send multiple bytes starting with '\x1b', '[''
// and followed by an 'A', 'B', 'C' or 'D' depending on which
// arrow is pressed.
case 'A': return ARROW_UP;
case 'B': return ARROW_DOWN;
case 'C': return ARROW_RIGHT;
case 'D': return ARROW_LEFT;
// Home key can also be sent as \x1b[H
case 'H': return HOME_KEY;
// End key can also be sent as \x1b[F
case 'F': return END_KEY;
}
}
} else if (seq[0] == 'O') {
switch (seq[1]) {
// Yes, Home key can ALSO be sent as \x1bOH
case 'H': return HOME_KEY;
// And... End key as \x1bOF
case 'F': return END_KEY;
}
}
return '\x1b';
} else {
return c;
}
}
 
int getWindowSize(int* screen_rows, int* screen_cols) {
struct winsize ws;
 
// Getting window size thanks to ioctl into the given
// winsize struct.
if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) == -1 || ws.ws_col == 0) {
return -1;
} else {
*screen_cols = ws.ws_col;
*screen_rows = ws.ws_row;
return 0;
}
}
 
void editorUpdateWindowSize() {
if (getWindowSize(&ec.screen_rows, &ec.screen_cols) == -1)
die("Failed to get window size");
ec.screen_rows -= 2; // Room for the status bar.
}
 
void editorHandleSigwinch() {
editorUpdateWindowSize();
if (ec.cursor_y > ec.screen_rows)
ec.cursor_y = ec.screen_rows - 1;
if (ec.cursor_x > ec.screen_cols)
ec.cursor_x = ec.screen_cols - 1;
editorRefreshScreen();
}
 
void editorHandleSigcont() {
disableRawMode();
consoleBufferOpen();
enableRawMode();
editorRefreshScreen();
}
 
void consoleBufferOpen() {
// Switch to another terminal buffer in order to be able to restore state at exit
// by calling consoleBufferClose().
if (write(STDOUT_FILENO, "\x1b[?47h", 6) == -1)
die("Error changing terminal buffer");
}
 
void consoleBufferClose() {
// Restore console to the state tte opened.
if (write(STDOUT_FILENO, "\x1b[?9l", 5) == -1 ||
write(STDOUT_FILENO, "\x1b[?47l", 6) == -1)
die("Error restoring buffer state");
 
/*struct a_buf ab = {.buf = NULL, .len = 0};
char* buf = NULL;
if (asprintf(&buf, "\x1b[%d;%dH\r\n", ec.screen_rows + 1, 1) == -1)
die("Error restoring buffer state");
abufAppend(&ab, buf, strlen(buf));
free(buf);
 
if (write(STDOUT_FILENO, ab.buf, ab.len) == -1)
die("Error restoring buffer state");
abufFree(&ab);*/
 
editorClearScreen();
}
 
/*** Syntax highlighting ***/
 
int isSeparator(int c) {
// strchr() looks to see if any one of the characters in the first string
// appear in the second string. If so, it returns a pointer to the
// character in the second string that matched. Otherwise, it
// returns NULL.
return isspace(c) || c == '\0' || strchr(",.()+-/*=~%<>[]:;", c) != NULL;
}
 
int isAlsoNumber(int c) {
return c == '.' || c == 'x' || c == 'a' || c == 'b' || c == 'c' || c == 'd' || c == 'e' || c == 'f';
}
 
void editorUpdateSyntax(editor_row* row) {
row -> highlight = realloc(row -> highlight, row -> render_size);
// void * memset ( void * ptr, int value, size_t num );
// Sets the first num bytes of the block of memory pointed by ptr to
// the specified value. With this we set all characters to HL_NORMAL.
memset(row -> highlight, HL_NORMAL, row -> render_size);
 
if (ec.syntax == NULL)
return;
 
char** keywords = ec.syntax -> keywords;
 
char* scs = ec.syntax -> singleline_comment_start;
char* mcs = ec.syntax -> multiline_comment_start;
char* mce = ec.syntax -> multiline_comment_end;
 
int scs_len = scs ? strlen(scs) : 0;
int mcs_len = mcs ? strlen(mcs) : 0;
int mce_len = mce ? strlen(mce) : 0;
 
int prev_sep = 1; // True (1) if the previous char is a separator, false otherwise.
int in_string = 0; // If != 0, inside a string. We also keep track if it's ' or "
int in_comment = (row -> idx > 0 && ec.row[row -> idx - 1].hl_open_comment); // This is ONLY used on ML comments.
 
int i = 0;
while (i < row -> render_size) {
char c = row -> render[i];
// Highlight type of the previous character.
unsigned char prev_highlight = (i > 0) ? row -> highlight[i - 1] : HL_NORMAL;
 
if (scs_len && !in_string && !in_comment) {
// int strncmp ( const char * str1, const char * str2, size_t num );
// Compares up to num characters of the C string str1 to those of the C string str2.
// This function starts comparing the first character of each string. If they are
// equal to each other, it continues with the following pairs until the characters
// differ, until a terminating null-character is reached, or until num characters
// match in both strings, whichever happens first.
if (!strncmp(&row -> render[i], scs, scs_len)) {
memset(&row -> highlight[i], HL_SL_COMMENT, row -> render_size - i);
break;
}
}
 
if (mcs_len && mce_len && !in_string) {
if (in_comment) {
row -> highlight[i] = HL_ML_COMMENT;
if (!strncmp(&row -> render[i], mce, mce_len)) {
memset(&row -> highlight[i], HL_ML_COMMENT, mce_len);
i += mce_len;
in_comment = 0;
prev_sep = 1;
continue;
} else {
i++;
continue;
}
} else if (!strncmp(&row -> render[i], mcs, mcs_len)) {
memset(&row -> highlight[i], HL_ML_COMMENT, mcs_len);
i += mcs_len;
in_comment = 1;
continue;
}
 
}
 
if (ec.syntax -> flags & HL_HIGHLIGHT_STRINGS) {
if (in_string) {
row -> highlight[i] = HL_STRING;
// If we’re in a string and the current character is a backslash (\),
// and there’s at least one more character in that line that comes
// after the backslash, then we highlight the character that comes
// after the backslash with HL_STRING and consume it. We increment
// i by 2 to consume both characters at once.
if (c == '\\' && i + 1 < row -> render_size) {
row -> highlight[i + 1] = HL_STRING;
i += 2;
continue;
}
 
if (c == in_string)
in_string = 0;
i++;
prev_sep = 1;
continue;
} else {
if (c == '"' || c == '\'') {
in_string = c;
row -> highlight[i] = HL_STRING;
i++;
continue;
}
}
}
 
if (ec.syntax -> flags & HL_HIGHLIGHT_NUMBERS) {
if ((isdigit(c) && (prev_sep || prev_highlight == HL_NUMBER)) ||
(isAlsoNumber(c) && prev_highlight == HL_NUMBER)) {
row -> highlight[i] = HL_NUMBER;
i++;
prev_sep = 0;
continue;
}
}
 
if (prev_sep) {
int j;
for (j = 0; keywords[j]; j++) {
int kw_len = strlen(keywords[j]);
int kw_2 = keywords[j][kw_len - 1] == '|';
if (kw_2)
kw_len--;
 
// Keywords require a separator both before and after the keyword.
if (!strncmp(&row -> render[i], keywords[j], kw_len) &&
isSeparator(row -> render[i + kw_len])) {
memset(&row -> highlight[i], kw_2 ? HL_KEYWORD_2 : HL_KEYWORD_1, kw_len);
i += kw_len;
break;
}
}
if (keywords[j] != NULL) {
prev_sep = 0;
continue;
}
}
 
prev_sep = isSeparator(c);
i++;
}
 
int changed = (row -> hl_open_comment != in_comment);
// This tells us whether the row ended as an unclosed multi-line
// comment or not.
row -> hl_open_comment = in_comment;
// A user could comment out an entire file just by changing one line.
// So it seems like we need to update the syntax of all the lines
// following the current line. However, we know the highlighting
// of the next line will not change if the value of this line’s
// // // hl_open_comment did not change. So we check if it changed, and
// // only call editorUpdateSyntax() on the next line if
// hl_open_comment changed (and if there is a next line in the file).
// Because editorUpdateSyntax() keeps calling itself with the next
// line, the change will continue to propagate to more and more lines
// until one of them is unchanged, at which point we know that all
// the lines after that one must be unchanged as well.
if (changed && row -> idx + 1 < ec.num_rows)
editorUpdateSyntax(&ec.row[row -> idx + 1]);
}
 
int editorSyntaxToColor(int highlight) {
// We return ANSI codes for colors.
// See https://en.wikipedia.org/wiki/ANSI_escape_code#Colors
// for a list of them.
switch (highlight) {
case HL_SL_COMMENT:
case HL_ML_COMMENT: return 36;
case HL_KEYWORD_1: return 31;
case HL_KEYWORD_2: return 32;
case HL_STRING: return 33;
case HL_NUMBER: return 35;
case HL_MATCH: return 34;
default: return 37;
}
}
 
void editorSelectSyntaxHighlight() {
ec.syntax = NULL;
if (ec.file_name == NULL)
return;
 
for (unsigned int j = 0; j < HL_DB_ENTRIES; j++) {
struct editor_syntax* es = &HL_DB[j];
unsigned int i = 0;
 
while (es -> file_match[i]) {
char* p = strstr(ec.file_name, es -> file_match[i]);
if (p != NULL) {
// Returns a pointer to the first occurrence of str2 in str1,
// or a null pointer if str2 is not part of str1.
int pat_len = strlen(es -> file_match[i]);
if (es -> file_match[i][0] != '.' || p[pat_len] == '\0') {
ec.syntax = es;
 
int file_row;
for (file_row = 0; file_row < ec.num_rows; file_row++) {
editorUpdateSyntax(&ec.row[file_row]);
}
 
return;
}
}
i++;
}
}
}
 
/*** Row operations ***/
 
int editorRowCursorXToRenderX(editor_row* row, int cursor_x) {
int render_x = 0;
int j;
// For each character, if its a tab we use rx % TTE_TAB_STOP
// to find out how many columns we are to the right of the last
// tab stop, and then subtract that from TTE_TAB_STOP - 1 to
// find out how many columns we are to the left of the next tab
// stop. We add that amount to rx to get just to the left of the
// next tab stop, and then the unconditional rx++ statement gets
// us right on the next tab stop. Notice how this works even if
// we are currently on a tab stop.
for (j = 0; j < cursor_x; j++) {
if (row -> chars[j] == '\t')
render_x += (TTE_TAB_STOP - 1) - (render_x % TTE_TAB_STOP);
render_x++;
}
return render_x;
}
 
int editorRowRenderXToCursorX(editor_row* row, int render_x) {
int cur_render_x = 0;
int cursor_x;
for (cursor_x = 0; cursor_x < row -> size; cursor_x++) {
if (row -> chars[cursor_x] == '\t')
cur_render_x += (TTE_TAB_STOP - 1) - (cur_render_x % TTE_TAB_STOP);
cur_render_x++;
 
if (cur_render_x > render_x)
return cursor_x;
}
return cursor_x;
}
 
void editorUpdateRow(editor_row* row) {
// First, we have to loop through the chars of the row
// and count the tabs in order to know how much memory
// to allocate for render. The maximum number of characters
// needed for each tab is 8. row->size already counts 1 for
// each tab, so we multiply the number of tabs by 7 and add
// that to row->size to get the maximum amount of memory we'll
// need for the rendered row.
int tabs = 0;
int j;
for (j = 0; j < row -> size; j++) {
if (row -> chars[j] == '\t')
tabs++;
}
free(row -> render);
row -> render = malloc(row -> size + tabs * (TTE_TAB_STOP - 1) + 1);
 
// After allocating the memory, we check whether the current character
// is a tab. If it is, we append one space (because each tab must
// advance the cursor forward at least one column), and then append
// spaces until we get to a tab stop, which is a column that is
// divisible by 8
int idx = 0;
for (j = 0; j < row -> size; j++) {
if (row -> chars[j] == '\t') {
row -> render[idx++] = ' ';
while (idx % TTE_TAB_STOP != 0)
row -> render[idx++] = ' ';
} else
row -> render[idx++] = row -> chars[j];
}
row -> render[idx] = '\0';
row -> render_size = idx;
 
editorUpdateSyntax(row);
}
 
void editorInsertRow(int at, char* s, size_t line_len) {
if (at < 0 || at > ec.num_rows)
return;
 
ec.row = realloc(ec.row, sizeof(editor_row) * (ec.num_rows + 1));
memmove(&ec.row[at + 1], &ec.row[at], sizeof(editor_row) * (ec.num_rows - at));
 
for (int j = at + 1; j <= ec.num_rows; j++) {
ec.row[j].idx++;
}
 
ec.row[at].idx = at;
 
ec.row[at].size = line_len;
ec.row[at].chars = malloc(line_len + 1); // We want to add terminator char '\0' at the end
memcpy(ec.row[at].chars, s, line_len);
ec.row[at].chars[line_len] = '\0';
 
ec.row[at].render_size = 0;
ec.row[at].render = NULL;
ec.row[at].highlight = NULL;
ec.row[at].hl_open_comment = 0;
editorUpdateRow(&ec.row[at]);
 
ec.num_rows++;
ec.dirty++;
}
 
void editorFreeRow(editor_row* row) {
free(row -> render);
free(row -> chars);
free(row -> highlight);
}
 
void editorDelRow(int at) {
if (at < 0 || at >= ec.num_rows)
return;
editorFreeRow(&ec.row[at]);
memmove(&ec.row[at], &ec.row[at + 1], sizeof(editor_row) * (ec.num_rows - at - 1));
 
for (int j = at; j < ec.num_rows - 1; j++) {
ec.row[j].idx--;
}
 
ec.num_rows--;
ec.dirty++;
}
 
// -1 down, 1 up
void editorFlipRow(int dir) {
editor_row c_row = ec.row[ec.cursor_y];
ec.row[ec.cursor_y] = ec.row[ec.cursor_y - dir];
ec.row[ec.cursor_y - dir] = c_row;
 
ec.row[ec.cursor_y].idx += dir;
ec.row[ec.cursor_y - dir].idx -= dir;
 
int first = (dir == 1) ? ec.cursor_y - 1 : ec.cursor_y;
editorUpdateSyntax(&ec.row[first]);
editorUpdateSyntax(&ec.row[first] + 1);
if (ec.num_rows - ec.cursor_y > 2)
editorUpdateSyntax(&ec.row[first] + 2);
 
ec.cursor_y -= dir;
ec.dirty++;
}
 
void editorCopy(int cut) {
ec.copied_char_buffer = realloc(ec.copied_char_buffer, strlen(ec.row[ec.cursor_y].chars) + 1);
strcpy(ec.copied_char_buffer, ec.row[ec.cursor_y].chars);
editorSetStatusMessage(cut ? "Content cut" : "Content copied");
}
 
void editorCut() {
editorCopy(-1);
editorDelRow(ec.cursor_y);
if (ec.num_rows - ec.cursor_y > 0)
editorUpdateSyntax(&ec.row[ec.cursor_y]);
if (ec.num_rows - ec.cursor_y > 1)
editorUpdateSyntax(&ec.row[ec.cursor_y + 1]);
ec.cursor_x = ec.cursor_y == ec.num_rows ? 0 : ec.row[ec.cursor_y].size;
}
 
void editorPaste() {
if (ec.copied_char_buffer == NULL)
return;
 
if (ec.cursor_y == ec.num_rows)
editorInsertRow(ec.cursor_y, ec.copied_char_buffer, strlen(ec.copied_char_buffer));
else
editorRowAppendString(&ec.row[ec.cursor_y], ec.copied_char_buffer, strlen(ec.copied_char_buffer));
ec.cursor_x += strlen(ec.copied_char_buffer);
}
 
void editorRowInsertChar(editor_row* row, int at, int c) {
if (at < 0 || at > row -> size)
at = row -> size;
// We need to allocate 2 bytes because we also have to make room for
// the null byte.
row -> chars = realloc(row -> chars, row -> size + 2);
// memmove it's like memcpy(), but is safe to use when the source and
// destination arrays overlap
memmove(&row -> chars[at + 1], &row -> chars[at], row -> size - at + 1);
row -> size++;
row -> chars[at] = c;
editorUpdateRow(row);
ec.dirty++; // This way we can see "how dirty" a file is.
}
 
void editorInsertNewline() {
// If we're at the beginning of a line, all we have to do is insert
// a new blank row before the line we're on.
if (ec.cursor_x == 0) {
editorInsertRow(ec.cursor_y, "", 0);
// Otherwise, we have to split the line we're on into two rows.
} else {
editor_row* row = &ec.row[ec.cursor_y];
editorInsertRow(ec.cursor_y + 1, &row -> chars[ec.cursor_x], row -> size - ec.cursor_x);
row = &ec.row[ec.cursor_y];
row -> size = ec.cursor_x;
row -> chars[row -> size] = '\0';
editorUpdateRow(row);
}
ec.cursor_y++;
ec.cursor_x = 0;
}
 
void editorRowAppendString(editor_row* row, char* s, size_t len) {
row -> chars = realloc(row -> chars, row -> size + len + 1);
memcpy(&row -> chars[row -> size], s, len);
row -> size += len;
row -> chars[row -> size] = '\0';
editorUpdateRow(row);
ec.dirty++;
}
 
void editorRowDelChar(editor_row* row, int at) {
if (at < 0 || at >= row -> size)
return;
// Overwriting the deleted character with the characters that come
// after it.
memmove(&row -> chars[at], &row -> chars[at + 1], row -> size - at);
row -> size--;
editorUpdateRow(row);
ec.dirty++;
}
 
/*** Editor operations ***/
 
void editorInsertChar(int c) {
// If this is true, the cursor is on the tilde line after the end of
// the file, so we need to append a new row to the file before inserting
// a character there.
if (ec.cursor_y == ec.num_rows)
editorInsertRow(ec.num_rows, "", 0);
editorRowInsertChar(&ec.row[ec.cursor_y], ec.cursor_x, c);
ec.cursor_x++; // This way we can see "how dirty" a file is.
}
 
void editorDelChar() {
// If the cursor is past the end of the file, there's nothing to delete.
if (ec.cursor_y == ec.num_rows)
return;
// Cursor is at the beginning of a file, there's nothing to delete.
if (ec.cursor_x == 0 && ec.cursor_y == 0)
return;
 
editor_row* row = &ec.row[ec.cursor_y];
if (ec.cursor_x > 0) {
editorRowDelChar(row, ec.cursor_x - 1);
ec.cursor_x--;
// Deleting a line and moving up all the content.
} else {
ec.cursor_x = ec.row[ec.cursor_y - 1].size;
editorRowAppendString(&ec.row[ec.cursor_y -1], row -> chars, row -> size);
editorDelRow(ec.cursor_y);
ec.cursor_y--;
}
}
 
/*** File I/O ***/
 
char* editorRowsToString(int* buf_len) {
int total_len = 0;
int j;
// Adding up the lengths of each row of text, adding 1
// to each one for the newline character we'll add to
// the end of each line.
for (j = 0; j < ec.num_rows; j++) {
total_len += ec.row[j].size + 1;
}
*buf_len = total_len;
 
char* buf = malloc(total_len);
char* p = buf;
// Copying the contents of each row to the end of the
// buffer, appending a newline character after each
// row.
for (j = 0; j < ec.num_rows; j++) {
memcpy(p, ec.row[j].chars, ec.row[j].size);
p += ec.row[j].size;
*p = '\n';
p++;
}
 
return buf;
}
 
void editorOpen(char* file_name) {
free(ec.file_name);
ec.file_name = strdup(file_name);
 
editorSelectSyntaxHighlight();
 
FILE* file = fopen(file_name, "r+");
if (!file)
die("Failed to open the file");
 
char* line = NULL;
// Unsigned int of at least 16 bit.
size_t line_cap = 0;
// Bigger than int
ssize_t line_len;
while ((line_len = getline(&line, &line_cap, file)) != -1) {
// We already know each row represents one line of text, there's no need
// to keep carriage return and newline characters.
if (line_len > 0 && (line[line_len - 1] == '\n' || line[line_len - 1] == '\r'))
line_len--;
editorInsertRow(ec.num_rows, line, line_len);
}
free(line);
fclose(file);
ec.dirty = 0;
}
 
void editorSave() {
if (ec.file_name == NULL) {
ec.file_name = editorPrompt("Save as: %s (ESC to cancel)", NULL);
if (ec.file_name == NULL) {
editorSetStatusMessage("Save aborted");
return;
}
editorSelectSyntaxHighlight();
}
 
int len;
char* buf = editorRowsToString(&len);
 
// We want to create if it doesn't already exist (O_CREAT flag), giving
// 0644 permissions (the standard ones). O_RDWR stands for reading and
// writing.
int fd = open(ec.file_name, O_RDWR | O_CREAT, 0644);
if (fd != -1) {
// ftruncate sets the file's size to the specified length.
if (ftruncate(fd, len) != -1) {
// Writing the file.
if (write(fd, buf, len) == len) {
close(fd);
free(buf);
ec.dirty = 0;
editorSetStatusMessage("%d bytes written to disk", len);
return;
}
}
close(fd);
}
 
free(buf);
editorSetStatusMessage("Cant's save file. Error occurred: %s", strerror(errno));
}
 
/*** Search section ***/
 
void editorSearchCallback(char* query, int key) {
// Index of the row that the last match was on, -1 if there was
// no last match.
static int last_match = -1;
// 1 for searching forward and -1 for searching backwards.
static int direction = 1;
 
static int saved_highlight_line;
static char* saved_hightlight = NULL;
 
if (saved_hightlight) {
memcpy(ec.row[saved_highlight_line].highlight, saved_hightlight, ec.row[saved_highlight_line].render_size);
free(saved_hightlight);
saved_hightlight = NULL;
}
 
// Checking if the user pressed Enter or Escape, in which case
// they are leaving search mode so we return immediately.
if (key == '\r' || key == '\x1b') {
last_match = -1;
direction = 1;
return;
} else if (key == ARROW_RIGHT || key == ARROW_DOWN) {
direction = 1;
} else if (key == ARROW_LEFT || key == ARROW_UP) {
if (last_match == -1) {
// If nothing matched and the left or up arrow key was pressed
return;
}
direction = -1;
} else {
last_match = -1;
direction = 1;
}
 
int current = last_match;
int i;
for (i = 0; i < ec.num_rows; i++) {
current += direction;
if (current == -1)
current = ec.num_rows - 1;
else if (current == ec.num_rows)
current = 0;
 
editor_row* row = &ec.row[current];
// We use strstr to check if query is a substring of the
// current row. It returns NULL if there is no match,
// oterwhise it returns a pointer to the matching substring.
char* match = strstr(row -> render, query);
if (match) {
last_match = current;
ec.cursor_y = current;
ec.cursor_x = editorRowRenderXToCursorX(row, match - row -> render);
// We set this like so to scroll to the bottom of the file so
// that the next screen refresh will cause the matching line to
// be at the very top of the screen.
ec.row_offset = ec.num_rows;
 
saved_highlight_line = current;
saved_hightlight = malloc(row -> render_size);
memcpy(saved_hightlight, row -> highlight, row -> render_size);
memset(&row -> highlight[match - row -> render], HL_MATCH, strlen(query));
break;
}
}
}
 
void editorSearch() {
int saved_cursor_x = ec.cursor_x;
int saved_cursor_y = ec.cursor_y;
int saved_col_offset = ec.col_offset;
int saved_row_offset = ec.row_offset;
 
char* query = editorPrompt("Search: %s (Use ESC / Enter / Arrows)", editorSearchCallback);
 
if (query) {
free(query);
// If query is NULL, that means they pressed Escape, so in that case we
// restore the cursor previous position.
} else {
ec.cursor_x = saved_cursor_x;
ec.cursor_y = saved_cursor_y;
ec.col_offset = saved_col_offset;
ec.row_offset = saved_row_offset;
}
}
 
/*** Append buffer section **/
 
void abufAppend(struct a_buf* ab, const char* s, int len) {
// Using realloc to get a block of free memory that is
// the size of the current string + the size of the string
// to be appended.
char* new = realloc(ab -> buf, ab -> len + len);
 
if (new == NULL)
return;
 
// Copying the string s at the end of the current data in
// the buffer.
memcpy(&new[ab -> len], s, len);
ab -> buf = new;
ab -> len += len;
}
 
void abufFree(struct a_buf* ab) {
// Deallocating buffer.
free(ab -> buf);
}
 
/*** Output section ***/
 
void editorScroll() {
ec.render_x = 0;
if (ec.cursor_y < ec.num_rows)
ec.render_x = editorRowCursorXToRenderX(&ec.row[ec.cursor_y], ec.cursor_x);
// The first if statement checks if the cursor is above the visible window,
// and if so, scrolls up to where the cursor is. The second if statement checks
// if the cursor is past the bottom of the visible window, and contains slightly
// more complicated arithmetic because ec.row_offset refers to what's at the top
// of the screen, and we have to get ec.screen_rows involved to talk about what's
// at the bottom of the screen.
if (ec.cursor_y < ec.row_offset)
ec.row_offset = ec.cursor_y;
if (ec.cursor_y >= ec.row_offset + ec.screen_rows)
ec.row_offset = ec.cursor_y - ec.screen_rows + 1;
 
if (ec.render_x < ec.col_offset)
ec.col_offset = ec.render_x;
if (ec.render_x >= ec.col_offset + ec.screen_cols)
ec.col_offset = ec.render_x - ec.screen_cols + 1;
}
 
void editorDrawStatusBar(struct a_buf* ab) {
// This switches to inverted colors.
// NOTE:
// The m command (Select Graphic Rendition) causes the text printed
// after it to be printed with various possible attributes including
// bold (1), underscore (4), blink (5), and inverted colors (7). An
// argument of 0 clears all attributes (the default one). See
// http://vt100.net/docs/vt100-ug/chapter3.html#SGR for more info.
abufAppend(ab, "\x1b[7m", 4);
 
char status[80], r_status[80];
// Showing up to 20 characters of the filename, followed by the number of lines.
int len = snprintf(status, sizeof(status), " Editing: %.20s %s", ec.file_name ? ec.file_name : "New file", ec.dirty ? "(modified)" : "");
int col_size = ec.row && ec.cursor_y <= ec.num_rows - 1 ? col_size = ec.row[ec.cursor_y].size : 0;
int r_len = snprintf(r_status, sizeof(r_status), "%d/%d lines %d/%d cols ", ec.cursor_y + 1 > ec.num_rows ? ec.num_rows : ec.cursor_y + 1, ec.num_rows,
ec.cursor_x + 1 > col_size ? col_size : ec.cursor_x + 1, col_size);
if (len > ec.screen_cols)
len = ec.screen_cols;
abufAppend(ab, status, len);
while (len < ec.screen_cols) {
if (ec.screen_cols - len == r_len) {
abufAppend(ab, r_status, r_len);
break;
} else {
abufAppend(ab, " ", 1);
len++;
}
}
// This switches back to normal colors.
abufAppend(ab, "\x1b[m", 3);
 
abufAppend(ab, "\r\n", 2);
}
 
void editorDrawMessageBar(struct a_buf *ab) {
// Clearing the message bar.
abufAppend(ab, "\x1b[K", 3);
int msg_len = strlen(ec.status_msg);
if (msg_len > ec.screen_cols)
msg_len = ec.screen_cols;
// We only show the message if its less than 5 secons old, but
// remember the screen is only being refreshed after each keypress.
if (msg_len && time(NULL) - ec.status_msg_time < 5)
abufAppend(ab, ec.status_msg, msg_len);
}
 
void editorDrawWelcomeMessage(struct a_buf* ab) {
char welcome[80];
// Using snprintf to truncate message in case the terminal
// is too tiny to handle the entire string.
int welcome_len = snprintf(welcome, sizeof(welcome),
"tte %s <http://dmoral.es/>", TTE_VERSION);
if (welcome_len > ec.screen_cols)
welcome_len = ec.screen_cols;
// Centering the message.
int padding = (ec.screen_cols - welcome_len) / 2;
// Remember that everything != 0 is true.
if (padding) {
abufAppend(ab, "~", 1);
padding--;
}
while (padding--)
abufAppend(ab, " ", 1);
abufAppend(ab, welcome, welcome_len);
}
 
// The ... argument makes editorSetStatusMessage() a variadic function,
// meaning it can take any number of arguments. C's way of dealing with
// these arguments is by having you call va_start() and va_end() on a
// // value of type va_list. The last argument before the ... (in this
// case, msg) must be passed to va_start(), so that the address of
// the next arguments is known. Then, between the va_start() and
// va_end() calls, you would call va_arg() and pass it the type of
// the next argument (which you usually get from the given format
// string) and it would return the value of that argument. In
// this case, we pass msg and args to vsnprintf() and it takes care
// of reading the format string and calling va_arg() to get each
// argument.
void editorSetStatusMessage(const char* msg, ...) {
va_list args;
va_start(args, msg);
vsnprintf(ec.status_msg, sizeof(ec.status_msg), msg, args);
va_end(args);
ec.status_msg_time = time(NULL);
}
 
void editorDrawRows(struct a_buf* ab) {
int y;
for (y = 0; y < ec.screen_rows; y++) {
int file_row = y + ec.row_offset;
if(file_row >= ec.num_rows) {
if (ec.num_rows == 0 && y == ec.screen_rows / 3)
editorDrawWelcomeMessage(ab);
else
abufAppend(ab, "~", 1);
} else {
int len = ec.row[file_row].render_size - ec.col_offset;
// len can be a negative number, meaning the user scrolled
// horizontally past the end of the line. In that case, we set
// len to 0 so that nothing is displayed on that line.
if (len < 0)
len = 0;
if (len > ec.screen_cols)
len = ec.screen_cols;
 
char* c = &ec.row[file_row].render[ec.col_offset];
unsigned char* highlight = &ec.row[file_row].highlight[ec.col_offset];
int current_color = -1;
int j;
for (j = 0; j < len; j++) {
// Displaying nonprintable characters as (A-Z, @, and ?).
if (iscntrl(c[j])) {
char sym = (c[j] <= 26) ? '@' + c[j] : '?';
abufAppend(ab, "\x1b[7m", 4);
abufAppend(ab, &sym, 1);
abufAppend(ab, "\x1b[m", 3);
if (current_color != -1) {
char buf[16];
int c_len = snprintf(buf, sizeof(buf), "\x1b[%dm", current_color);
abufAppend(ab, buf, c_len);
}
} else if (highlight[j] == HL_NORMAL) {
if (current_color != -1) {
abufAppend(ab, "\x1b[39m", 5);
current_color = -1;
}
abufAppend(ab, &c[j], 1);
} else {
int color = editorSyntaxToColor(highlight[j]);
// We only use escape sequence if the new color is different
// from the last character's color.
if (color != current_color) {
current_color = color;
char buf[16];
int c_len = snprintf(buf, sizeof(buf), "\x1b[%dm", color);
abufAppend(ab, buf, c_len);
}
 
abufAppend(ab, &c[j], 1);
}
}
abufAppend(ab, "\x1b[39m", 5);
}
 
// Redrawing each line instead of the whole screen.
abufAppend(ab, "\x1b[K", 3);
// Addind a new line
abufAppend(ab, "\r\n", 2);
}
}
 
void editorRefreshScreen() {
editorScroll();
 
struct a_buf ab = ABUF_INIT;
 
// Hiding the cursor while the screen is refreshing.
// See http://vt100.net/docs/vt100-ug/chapter3.html#S3.3.4
// for more info.
abufAppend(&ab, "\x1b[?25l", 6);
abufAppend(&ab, "\x1b[H", 3);
 
editorDrawRows(&ab);
editorDrawStatusBar(&ab);
editorDrawMessageBar(&ab);
 
// Moving the cursor where it should be.
char buf[32];
snprintf(buf, sizeof(buf), "\x1b[%d;%dH", (ec.cursor_y - ec.row_offset) + 1, (ec.render_x - ec.col_offset) + 1);
abufAppend(&ab, buf, strlen(buf));
 
// Showing again the cursor.
abufAppend(&ab, "\x1b[?25h", 6);
 
// Writing all content at once
write(STDOUT_FILENO, ab.buf, ab.len);
abufFree(&ab);
}
 
void editorClearScreen() {
// Writing 4 bytes out to the terminal:
// - (1 byte) \x1b : escape character
// - (3 bytes) [2J : Clears the entire screen, see
// http://vt100.net/docs/vt100-ug/chapter3.html#ED
// for more info.
write(STDOUT_FILENO, "\x1b[2J", 4);
// Writing 3 bytes to reposition the cursor back at
// the top-left corner, see
// http://vt100.net/docs/vt100-ug/chapter3.html#CUP
// for more info.
write(STDOUT_FILENO, "\x1b[H", 3);
}
 
/*** Input section ***/
 
char* editorPrompt(char* prompt, void (*callback)(char*, int)) {
size_t buf_size = 128;
char* buf = malloc(buf_size);
 
size_t buf_len = 0;
buf[0] = '\0';
 
while (1) {
editorSetStatusMessage(prompt, buf);
editorRefreshScreen();
 
int c = editorReadKey();
if (c == DEL_KEY || c == CTRL_KEY('h') || c == BACKSPACE) {
if (buf_len != 0)
buf[--buf_len] = '\0';
} else if (c == '\x1b') {
editorSetStatusMessage("");
if (callback)
callback(buf, c);
free(buf);
return NULL;
} else if (c == '\r') {
if (buf_len != 0) {
editorSetStatusMessage("");
if (callback)
callback(buf, c);
return buf;
}
} else if (!iscntrl(c) && isprint(c)) {
if (buf_len == buf_size - 1) {
buf_size *= 2;
buf = realloc(buf, buf_size);
}
buf[buf_len++] = c;
buf[buf_len] = '\0';
}
 
if (callback)
callback(buf, c);
}
}
 
void editorMoveCursor(int key) {
editor_row* row = (ec.cursor_y >= ec.num_rows) ? NULL : &ec.row[ec.cursor_y];
 
switch (key) {
case ARROW_LEFT:
if (ec.cursor_x != 0)
ec.cursor_x--;
// If <- is pressed, move to the end of the previous line
else if (ec.cursor_y > 0) {
ec.cursor_y--;
ec.cursor_x = ec.row[ec.cursor_y].size;
}
break;
case ARROW_RIGHT:
if (row && ec.cursor_x < row -> size)
ec.cursor_x++;
// If -> is pressed, move to the start of the next line
else if (row && ec.cursor_x == row -> size) {
ec.cursor_y++;
ec.cursor_x = 0;
}
break;
case ARROW_UP:
if (ec.cursor_y != 0)
ec.cursor_y--;
break;
case ARROW_DOWN:
if (ec.cursor_y < ec.num_rows)
ec.cursor_y++;
break;
}
 
// Move cursor_x if it ends up past the end of the line it's on
row = (ec.cursor_y >= ec.num_rows) ? NULL : &ec.row[ec.cursor_y];
int row_len = row ? row -> size : 0;
if (ec.cursor_x > row_len)
ec.cursor_x = row_len;
}
 
void editorProcessKeypress() {
static int quit_times = TTE_QUIT_TIMES;
 
int c = editorReadKey();
 
switch (c) {
case '\r': // Enter key
editorInsertNewline();
break;
case CTRL_KEY('q'):
if (ec.dirty && quit_times > 0) {
editorSetStatusMessage("Warning! File has unsaved changes. Press Ctrl-Q %d more time%s to quit", quit_times, quit_times > 1 ? "s" : "");
quit_times--;
return;
}
editorClearScreen();
consoleBufferClose();
exit(0);
break;
case CTRL_KEY('s'):
editorSave();
break;
case CTRL_KEY('e'):
if (ec.cursor_y > 0 && ec.cursor_y <= ec.num_rows - 1)
editorFlipRow(1);
break;
case CTRL_KEY('d'):
if (ec.cursor_y < ec.num_rows - 1)
editorFlipRow(-1);
break;
case CTRL_KEY('x'):
if (ec.cursor_y < ec.num_rows)
editorCut();
break;
case CTRL_KEY('c'):
if (ec.cursor_y < ec.num_rows)
editorCopy(0);
break;
case CTRL_KEY('v'):
editorPaste();
break;
case CTRL_KEY('p'):
consoleBufferClose();
kill(0, SIGTSTP);
case ARROW_UP:
case ARROW_DOWN:
case ARROW_LEFT:
case ARROW_RIGHT:
editorMoveCursor(c);
break;
case PAGE_UP:
case PAGE_DOWN:
{ // You can't declare variables directly inside a switch statement.
if (c == PAGE_UP)
ec.cursor_y = ec.row_offset;
else if (c == PAGE_DOWN)
ec.cursor_y = ec.row_offset + ec.screen_rows - 1;
 
int times = ec.screen_rows;
while (times--)
editorMoveCursor(c == PAGE_UP ? ARROW_UP : ARROW_DOWN);
}
break;
case HOME_KEY:
ec.cursor_x = 0;
break;
case END_KEY:
if (ec.cursor_y < ec.num_rows)
ec.cursor_x = ec.row[ec.cursor_y].size;
break;
case CTRL_KEY('f'):
editorSearch();
break;
case BACKSPACE:
case CTRL_KEY('h'):
case DEL_KEY:
if (c == DEL_KEY)
editorMoveCursor(ARROW_RIGHT);
editorDelChar();
break;
case CTRL_KEY('l'):
case '\x1b': // Escape key
break;
default:
editorInsertChar(c);
break;
}
 
quit_times = TTE_QUIT_TIMES;
}
 
/*** Init section ***/
 
void initEditor() {
ec.cursor_x = 0;
ec.cursor_y = 0;
ec.render_x = 0;
ec.row_offset = 0;
ec.col_offset = 0;
ec.num_rows = 0;
ec.row = NULL;
ec.dirty = 0;
ec.file_name = NULL;
ec.status_msg[0] = '\0';
ec.status_msg_time = 0;
ec.copied_char_buffer = NULL;
ec.syntax = NULL;
 
editorUpdateWindowSize();
// The SIGWINCH signal is sent to a process when its controlling
// terminal changes its size (a window change).
signal(SIGWINCH, editorHandleSigwinch);
// The SIGCONT signal instructs the operating system to continue
// (restart) a process previously paused by the SIGSTOP or SIGTSTP
// signal.
signal(SIGCONT, editorHandleSigcont);
}
 
void printHelp() {
printf("Usage: tte [OPTIONS] [FILE]\n\n");
printf("\nKEYBINDINGS\n-----------\n\n");
printf("Keybinding\t\tAction\n\n");
printf("Ctrl-Q \t\tExit\n");
printf("Ctrl-S \t\tSave\n");
printf("Ctrl-F \t\tSearch. Esc, enter and arrows to interact once searching\n");
printf("Ctrl-E \t\tFlip line upwards\n");
printf("Ctrl-D \t\tFlip line downwards\n");
printf("Ctrl-C \t\tCopy line\n");
printf("Ctrl-X \t\tCut line\n");
printf("Ctrl-V \t\tPaste line\n");
printf("Ctrl-P \t\tPause tte (type \"fg\" to resume)\n");
 
printf("\n\nOPTIONS\n-------\n\n");
printf("Option \t\tAction\n\n");
printf("-h | --help \t\tPrints the help\n");
printf("-v | --version\t\tPrints the version of tte\n");
 
printf("\n\nFor now, usage of ISO 8859-1 is recommended.\n");
}
 
// 1 if editor should open, 0 otherwise, -1 if the program should exit
int handleArgs(int argc, char* argv[]) {
if (argc == 1)
return 0;
 
if (argc >= 2) {
if (strncmp("-h", argv[1], 2) == 0 || strncmp("--help", argv[1], 6) == 0) {
printHelp();
return -1;
} else if(strncmp("-v", argv[1], 2) == 0 || strncmp("--version", argv[1], 9) == 0) {
printf("tte - version %s\n", TTE_VERSION);
return -1;
}
}
 
return 1;
}
 
int main(int argc, char* argv[]) {
initEditor();
int arg_response = handleArgs(argc, argv);
if (arg_response == 1)
editorOpen(argv[1]);
else if (arg_response == -1)
return 0;
enableRawMode();
 
editorSetStatusMessage(" Ctrl-Q to quit | Ctrl-S to save | (tte -h | --help for more info)");
 
while (1) {
editorRefreshScreen();
editorProcessKeypress();
}
 
return 0;
}