edit.c

具有IDE功能的编辑器

    edit->stat.st_mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
    edit->stat.st_uid = getuid ();
    edit->stat.st_gid = getgid ();
    edit->bracket = -1;
    edit->last_get_mb_rule = -2;
    if (!dir)
	dir = "";
    f = (char *) filename;
    if (filename) {
	f = catstrs (dir, filename, 0);
	if (edit_file_is_open)
	    if ((*edit_file_is_open) (f)) {
		if (to_free)
		    free (edit);
		return 0;
	    }
    }
    if (edit_find_filter (f) < 0) {
#ifdef CR_LF_TRANSLATION
	use_filter = 1;
#endif
	if (edit_open_file (edit, f, text, text_size)) {
/* edit_load_file already gives an error message */
	    if (to_free)
		free (edit);
	    return 0;
	}
    } else {
	use_filter = 1;
	if (edit_open_file (edit, 0, "", 0)) {
	    if (to_free)
		free (edit);
	    return 0;
	}
    }
    edit->force |= REDRAW_PAGE;
    if (filename) {
	filename = catstrs (dir, filename, 0);
	edit_split_filename (edit, (char *) filename);
    } else {
	edit->filename = (char *) strdup ("");
	edit->dir = (char *) strdup (dir);
    }
    edit->stack_size = START_STACK_SIZE;
    edit->stack_size_mask = START_STACK_SIZE - 1;
    edit->undo_stack = malloc ((edit->stack_size + 10) * sizeof (long));
    edit->total_lines = edit_count_lines (edit, 0, edit->last_byte);
    if (use_filter) {
	struct stat st;
	push_action_disabled = 1;
	if (check_file_access (edit, filename, &st)) {
	    edit_clean (edit);
	    if (to_free)
		free (edit);
	    return 0;
	}
	edit->stat = st;
	if (!edit_insert_file (edit, f)) {
	    edit_clean (edit);
	    if (to_free)
		free (edit);
	    return 0;
	}
/* FIXME: this should be an unmodification() function */
	push_action_disabled = 0;
    }
    edit->modified = 0;
    edit_load_syntax (edit, 0, 0);
    {
	int fg, bg;
	edit_get_syntax_color (edit, -1, &fg, &bg);
    }
    return edit;
}

/* clear the edit struct, freeing everything in it. returns 1 on success */
int edit_clean (WEdit * edit)
{
    if (edit) {
	int j = 0;
	edit_free_syntax_rules (edit);
	edit_get_wide_byte (edit, -1);
	book_mark_flush (edit, -1);
	for (; j <= MAXBUFF; j++) {
	    if (edit->buffers1[j] != NULL)
		free (edit->buffers1[j]);
	    if (edit->buffers2[j] != NULL)
		free (edit->buffers2[j]);
	}

	if (edit->undo_stack)
	    free (edit->undo_stack);
	if (edit->filename)
	    free (edit->filename);
	if (edit->dir)
	    free (edit->dir);
/* we don't want to clear the widget */
	memset (&(edit->from_here), 0, (unsigned long) &(edit->to_here) - (unsigned long) &(edit->from_here));
	return 1;
    }
    return 0;
}


/* returns 1 on success */
int edit_renew (WEdit * edit)
{
    int lines = edit->num_widget_lines;
    int columns = edit->num_widget_columns;
    char *dir;

    if (edit->dir)
	dir = (char *) strdup (edit->dir);
    else
	dir = 0;
    
    edit_clean (edit);
    if (!edit_init (edit, lines, columns, 0, "", dir, 0))
	return 0;
    return 1;
}

/* returns 1 on success, if returns 0, the edit struct would have been free'd */
int edit_reload (WEdit * edit, const char *filename, const char *text, const char *dir, unsigned long text_size)
{
    WEdit *e;
    int lines = edit->num_widget_lines;
    int columns = edit->num_widget_columns;
    e = malloc (sizeof (WEdit));
    memset (e, 0, sizeof (WEdit));
    e->widget = edit->widget;
    e->macro_i = -1;
    if (!edit_init (e, lines, columns, filename, text, dir, text_size)) {
	free (e);
	return 0;
    }
    edit_clean (edit);
    memcpy (edit, e, sizeof (WEdit));
    free (e);
    return 1;
}


/*
   Recording stack for undo:
   The following is an implementation of a compressed stack. Identical
   pushes are recorded by a negative prefix indicating the number of times the
   same char was pushed. This saves space for repeated curs-left or curs-right
   delete etc.

   eg:

  pushed:       stored:

   a
   b             a
   b            -3
   b             b
   c  -->       -4
   c             c
   c             d
   c
   d

   If the stack long int is 0-255 it represents a normal insert (from a backspace),
   256-512 is an insert ahead (from a delete), If it is betwen 600 and 700 it is one
   of the cursor functions #define'd in edit.h. 1000 through 700'000'000 is to
   set edit->mark1 position. 700'000'000 through 1400'000'000 is to set edit->mark2
   position.

   The only way the cursor moves or the buffer is changed is through the routines:
   insert, backspace, insert_ahead, delete, and cursor_move.
   These record the reverse undo movements onto the stack each time they are
   called.

   Each key press results in a set of actions (insert; delete ...). So each time
   a key is pressed the current position of start_display is pushed as
   KEY_PRESS + start_display. Then for undoing, we pop until we get to a number
   over KEY_PRESS. We then assign this number less KEY_PRESS to start_display. So undo
   tracks scrolling and key actions exactly. (KEY_PRESS is about (2^31) * (2/3) = 1400'000'000)

*/

void edit_push_action (WEdit * edit, long c,...)
{
    unsigned long sp = edit->stack_pointer;
    unsigned long spm1;
    long *t;
/* first enlarge the stack if necessary */
    if (sp > edit->stack_size - 10) {	/* say */
	if (option_max_undo < 256)
	    option_max_undo = 256;
	if (edit->stack_size < option_max_undo) {
	    t = malloc ((edit->stack_size * 2 + 10) * sizeof (long));
	    if (t) {
		memcpy (t, edit->undo_stack, sizeof (long) * edit->stack_size);
		free (edit->undo_stack);
		edit->undo_stack = t;
		edit->stack_size <<= 1;
		edit->stack_size_mask = edit->stack_size - 1;
	    }
	}
    }
    spm1 = (edit->stack_pointer - 1) & edit->stack_size_mask;
    if (push_action_disabled)
	return;

#ifdef FAST_MOVE_CURSOR
    if (c == CURS_LEFT_LOTS || c == CURS_RIGHT_LOTS) {
	va_list ap;
	edit->undo_stack[sp] = c == CURS_LEFT_LOTS ? CURS_LEFT : CURS_RIGHT;
	edit->stack_pointer = (edit->stack_pointer + 1) & edit->stack_size_mask;
	va_start (ap, c);
	c = -(va_arg (ap, int));
	va_end (ap);
    } else
#endif				/* ! FAST_MOVE_CURSOR */
    if (spm1 != edit->stack_bottom && ((sp - 2) & edit->stack_size_mask) != edit->stack_bottom) {
	int d;
	if (edit->undo_stack[spm1] < 0) {
	    d = edit->undo_stack[(sp - 2) & edit->stack_size_mask];
	    if (d == c) {
		if (edit->undo_stack[spm1] > -1000000000) {
		    if (c < KEY_PRESS)	/* --> no need to push multiple do-nothings */
			edit->undo_stack[spm1]--;
		    return;
		}
	    }
/* #define NO_STACK_CURSMOVE_ANIHILATION */
#ifndef NO_STACK_CURSMOVE_ANIHILATION
	    else if ((c == CURS_LEFT && d == CURS_RIGHT)
		     || (c == CURS_RIGHT && d == CURS_LEFT)) {	/* a left then a right anihilate each other */
		if (edit->undo_stack[spm1] == -2)
		    edit->stack_pointer = spm1;
		else
		    edit->undo_stack[spm1]++;
		return;
	    }
#endif
	} else {
	    d = edit->undo_stack[spm1];
	    if (d == c) {
		if (c >= KEY_PRESS)
		    return;	/* --> no need to push multiple do-nothings */
		edit->undo_stack[sp] = -2;
		goto check_bottom;
	    }
#ifndef NO_STACK_CURSMOVE_ANIHILATION
	    else if ((c == CURS_LEFT && d == CURS_RIGHT)
		     || (c == CURS_RIGHT && d == CURS_LEFT)) {	/* a left then a right anihilate each other */
		edit->stack_pointer = spm1;
		return;
	    }
#endif
	}
    }
    edit->undo_stack[sp] = c;
  check_bottom:

    edit->stack_pointer = (edit->stack_pointer + 1) & edit->stack_size_mask;

/*if the sp wraps round and catches the stack_bottom then erase the first set of actions on the stack to make space - by moving stack_bottom forward one "key press" */
    c = (edit->stack_pointer + 2) & edit->stack_size_mask;
    if (c == edit->stack_bottom || ((c + 1) & edit->stack_size_mask) == edit->stack_bottom)
	do {
	    edit->stack_bottom = (edit->stack_bottom + 1) & edit->stack_size_mask;
	} while (edit->undo_stack[edit->stack_bottom] < KEY_PRESS && edit->stack_bottom != edit->stack_pointer);

/*If a single key produced enough pushes to wrap all the way round then we would notice that the [stack_bottom] does not contain KEY_PRESS. The stack is then initialised: */
    if (edit->stack_pointer != edit->stack_bottom && edit->undo_stack[edit->stack_bottom] < KEY_PRESS)
	edit->stack_bottom = edit->stack_pointer = 0;
}

/*
   TODO: if the user undos until the stack bottom, and the stack has not wrapped,
   then the file should be as it was when he loaded up. Then set edit->modified to 0.
 */
long pop_action (WEdit * edit)
{
    long c;
    unsigned long sp = edit->stack_pointer;
    if (sp == edit->stack_bottom) {
	return STACK_BOTTOM;
    }
    sp = (sp - 1) & edit->stack_size_mask;
    if ((c = edit->undo_stack[sp]) >= 0) {
/*	edit->undo_stack[sp] = '@'; */
	edit->stack_pointer = (edit->stack_pointer - 1) & edit->stack_size_mask;
	return c;
    }
    if (sp == edit->stack_bottom) {
	return STACK_BOTTOM;
    }
    c = edit->undo_stack[(sp - 1) & edit->stack_size_mask];
    if (edit->undo_stack[sp] == -2) {
/*      edit->undo_stack[sp] = '@'; */
	edit->stack_pointer = sp;
    } else
	edit->undo_stack[sp]++;

    return c;
}

/* is called whenever a modification is made by one of the four routines below */
static inline void edit_modification (WEdit * edit, long p)
{
    edit->caches_valid = 0;
    edit->modified = 1;
    edit->screen_modified = 1;
    if (edit->last_get_mb_rule > p - 1) {
	edit->last_get_mb_rule = p - 1;
	edit->mb_invalidate = 1;
    }
    if (edit->last_get_mb_rule > p - 1) {
	edit->last_get_rule = p - 1;
	edit->syntax_invalidate = 1;
    }
}

/*
   Basic low level single character buffer alterations and movements at the cursor.
   Returns char passed over, inserted or removed.
 */

void edit_insert (WEdit * edit, int c)
{
/* check if file has grown to large */
    if (edit->last_byte >= SIZE_LIMIT)
	return;

/* first we must update the position of the display window */
    if (edit->curs1 < edit->start_display) {
	edit->start_display++;
	if (c == '\n')
	    edit->start_line++;
    }
/* now we must update some info on the file and check if a redraw is required */
    if (c == '\n') {
	if (edit->book_mark)
	    book_mark_inc (edit, edit->curs_line);
	edit->curs_line++;
	edit->total_lines++;
	edit->force |= REDRAW_LINE_ABOVE | REDRAW_AFTER_CURSOR;
    }
/* tell that we've modified the file */
    edit_modification (edit, edit->curs1);

/* save the reverse command onto the undo stack */
    edit_push_action (edit, BACKSPACE);

/* update markers */
    edit->mark1 += (edit->mark1 > edit->curs1);
    edit->mark2 += (edit->mark2 > edit->curs1);

/* add a new buffer if we've reached the end of the last one */
    if (!(edit->curs1 & M_EDIT_BUF_SIZE))
	edit->buffers1[edit->curs1 >> S_EDIT_BUF_SIZE] = malloc (EDIT_BUF_SIZE);

/* perfprm the insertion */
    edit->buffers1[edit->curs1 >> S_EDIT_BUF_SIZE][edit->curs1 & M_EDIT_BUF_SIZE] = (unsigned char) c;

/* update file length */
    edit->last_byte++;

/* update cursor position */
    edit->curs1++;
}


/* same as edit_insert and move left */
void edit_insert_ahead (WEdit * edit, int c)
{
    if (edit->last_byte >= SIZE_LIMIT)
	return;
    if (edit->curs1 < edit->start_display) {
	edit->start_display++;
	if (c == '\n')
	    edit->start_line++;
    }
    if (c == '\n') {
	if (edit->book_mark)
	    book_mark_inc (edit, edit->curs_line);
	edit->total_lines++;
	edit->force |= REDRAW_AFTER_CURSOR;
    }
    edit_modification (edit, edit->curs1);
    edit_push_action (edit, DELETE);

    edit->mark1 += (edit->mark1 >= edit->curs1);
    edit->mark2 += (edit->mark2 >= edit->curs1);

    if (!((edit->curs2 + 1) & M_EDIT_BUF_SIZE))
	edit->buffers2[(edit->curs2 + 1) >> S_EDIT_BUF_SIZE] = malloc (EDIT_BUF_SIZE);
    edit->buffers2[edit->curs2 >> S_EDIT_BUF_SIZE][EDIT_BUF_SIZE - (edit->curs2 & M_EDIT_BUF_SIZE) - 1] = c;

    edit->last_byte++;
    edit->curs2++;
}


int edit_delete (WEdit * edit)
{
    int p;
    if (!edit->curs2)
	return 0;

    edit->mark1 -= (edit->mark1 > edit->curs1);
    edit->mark2 -= (edit->mark2 > edit->curs1);

    p = edit->buffers2[(edit->curs2 - 1) >> S_EDIT_BUF_SIZE][EDIT_BUF_SIZE - ((edit->curs2 - 1) & M_EDIT_BUF_SIZE) - 1];

    if (!(edit->curs2 & M_EDIT_BUF_SIZE)) {
	free (edit->buffers2[edit->curs2 >> S_EDIT_BUF_SIZE]);
	edit->buffers2[edit->curs2 >> S_EDIT_BUF_SIZE] = NULL;
    }
    edit->last_byte--;
    edit->curs2--;

    if (p == '\n') {
	if (edit->book_mark)
	    book_mark_dec (edit, edit->curs_line);
	edit->total_lines--;
	edit->force |= REDRAW_AFTER_CURSOR;
    }
    edit_push_action (edit, p + 256);
    if (edit->curs1 < edit->start_display) {
	edit->start_display--;
	if (p == '\n')
	    edit->start_line--;
    }
    edit_modification (edit, edit->curs1);

    return p;
}


int edit_backspace (WEdit * edit)
{
    int p;
    if (!edit->curs1)
	return 0;

    edit->mark1 -= (edit->mark1 >= edit->curs1);
    edit->mark2 -= (edit->mark2 >= edit->curs1);

    p = *(edit->buffers1[(edit->curs1 - 1) >> S_EDIT_BUF_SIZE] + ((edit->curs1 - 1) & M_EDIT_BUF_SIZE));
    if (!((edit->curs1 - 1) & M_EDIT_BUF_SIZE)) {
	free (edit->buffers1[edit->curs1 >> S_EDIT_BUF_SIZE]);
	edit->buffers1[edit->curs1 >> S_EDIT_BUF_SIZE] = NULL;
    }
    edit->last_byte--;
    edit->curs1--;

    if (p == '\n') {
	if (edit->book_mark)
	    book_mark_dec (edit, edit->curs_line);
	edit->curs_line--;
	edit->total_lines--;
	edit->force |= REDRAW_AFTER_CURSOR;
    }
    edit_push_action (edit, p);

    if (edit->curs1 < edit->start_display) {
	edit->start_display--;
	if (p == '\n')
	    edit->start_line--;
    }
    edit_modification (edit, edit->curs1);

    return p;
}

int edit_delete_wide (WEdit * edit)
{
    struct mb_rule r;
    r = get_mb_rule (edit, edit->curs1);
    edit_delete (edit);
    while (r.end--)
	edit_delete (edit);
    return r.ch;
}

extern int option_utf_interpretation;

void edit_insert_wide (WEdit * edit, wchar_t wc)
{
    unsigned char *c;
    if (!option_utf_interpretation) {
	edit_insert (edit, wc & 0xFF);
	return;
    }
    c = wcrtomb_ucs4_to_utf8 (wc);
    if (!*c) {
	edit_insert (edit, *c);