Vendor import of less v632.vendor/less/v632

1 files changed, 166 insertions, 37 deletions

diff --git a/input.c b/input.c
index ffd2f13e3f3f..0e021e1d05e1 100644
--- a/input.c
+++ b/input.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2022  Mark Nudelman
+ * Copyright (C) 1984-2023  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -25,6 +25,7 @@ extern int quit_if_one_screen;
 extern int sigs;
 extern int ignore_eoi;
 extern int status_col;
+extern int wordwrap;
 extern POSITION start_attnpos;
 extern POSITION end_attnpos;
 #if HILITE_SEARCH
@@ -34,26 +35,63 @@ extern int show_attn;
 #endif
 
 /*
+ * Set the status column.
+ *  base  Position of first char in line.
+ *  disp  First visible char.
+ *        Different than base_pos if line is shifted.
+ *  edisp Last visible char. 
+ *  eol   End of line. Normally the newline.
+ *        Different than edisp if line is chopped.
+ */
+static void init_status_col(POSITION base_pos, POSITION disp_pos, POSITION edisp_pos, POSITION eol_pos)
+{
+	int hl_before = (chop_line() && disp_pos != NULL_POSITION) ?
+	    is_hilited_attr(base_pos, disp_pos, TRUE, NULL) : 0;
+	int hl_after = (chop_line()) ?
+	    is_hilited_attr(edisp_pos, eol_pos, TRUE, NULL) : 0;
+	int attr;
+	char ch;
+
+	if (hl_before && hl_after)
+	{
+		attr = hl_after;
+		ch = '=';
+	} else if (hl_before)
+	{
+		attr = hl_before;
+		ch = '<';
+	} else if (hl_after)
+	{
+		attr = hl_after;
+		ch = '>';
+	} else 
+	{
+		attr = is_hilited_attr(base_pos, eol_pos, TRUE, NULL);
+		ch = '*';
+	}
+	if (attr)
+		set_status_col(ch, attr);
+}
+
+/*
  * Get the next line.
  * A "current" position is passed and a "new" position is returned.
  * The current position is the position of the first character of
  * a line.  The new position is the position of the first character
  * of the NEXT line.  The line obtained is the line starting at curr_pos.
  */
-	public POSITION
-forw_line_seg(curr_pos, skipeol, rscroll, nochop)
-	POSITION curr_pos;
-	int skipeol;
-	int rscroll;
-	int nochop;
+public POSITION forw_line_seg(POSITION curr_pos, int skipeol, int rscroll, int nochop)
 {
 	POSITION base_pos;
 	POSITION new_pos;
+	POSITION edisp_pos;
 	int c;
 	int blankline;
 	int endline;
 	int chopped;
 	int backchars;
+	POSITION wrap_pos;
+	int skipped_leading;
 
 get_forw_line:
 	if (curr_pos == NULL_POSITION)
@@ -124,6 +162,15 @@ get_forw_line:
 		if (backchars > 0)
 		{
 			pshift_all();
+			if (wordwrap && (c == ' ' || c == '\t'))
+			{
+				do
+				{
+					new_pos++;
+					c = ch_forw_get();
+				} while (c == ' ' || c == '\t');
+				backchars = 1;
+			}
 			new_pos -= backchars;
 			while (--backchars >= 0)
 				(void) ch_back_get();
@@ -142,6 +189,8 @@ get_forw_line:
 		return (NULL_POSITION);
 	}
 	blankline = (c == '\n' || c == '\r');
+	wrap_pos = NULL_POSITION;
+	skipped_leading = FALSE;
 
 	/*
 	 * Read each character in the line and append to the line buffer.
@@ -167,6 +216,7 @@ get_forw_line:
 				endline = FALSE;
 			} else
 				endline = TRUE;
+			edisp_pos = new_pos;
 			break;
 		}
 		if (c != '\r')
@@ -186,6 +236,7 @@ get_forw_line:
 			if (skipeol)
 			{
 				/* Read to end of line. */
+				edisp_pos = ch_tell();
 				do
 				{
 					if (ABORT_SIGS())
@@ -201,11 +252,50 @@ get_forw_line:
 				chopped = TRUE;
 			} else
 			{
-				new_pos = ch_tell() - backchars;
+				if (!wordwrap)
+					new_pos = ch_tell() - backchars;
+				else
+				{
+					/*
+					 * We're word-wrapping, so go back to the last space.
+					 * However, if it's the space itself that couldn't fit,
+					 * simply ignore it and any subsequent spaces.
+					 */
+					if (c == ' ' || c == '\t')
+					{
+						do
+						{
+							new_pos = ch_tell();
+							c = ch_forw_get();
+						} while (c == ' ' || c == '\t');
+						if (c == '\r')
+							c = ch_forw_get();
+						if (c == '\n')
+							new_pos = ch_tell();
+					} else if (wrap_pos == NULL_POSITION)
+						new_pos = ch_tell() - backchars;
+					else
+					{
+						new_pos = wrap_pos;
+						loadc();
+					}
+				}
 				endline = FALSE;
 			}
 			break;
 		}
+		if (wordwrap)
+		{
+			if (c == ' ' || c == '\t')
+			{
+				if (skipped_leading)
+				{
+					wrap_pos = ch_tell();
+					savec();
+				}
+			} else
+				skipped_leading = TRUE;
+		}
 		c = ch_forw_get();
 	}
 
@@ -228,13 +318,8 @@ get_forw_line:
 		curr_pos = new_pos;
 		goto get_forw_line;
 	}
-
 	if (status_col)
-	{
-		int attr = is_hilited_attr(base_pos, ch_tell()-1, 1, NULL);
-		if (attr)
-			set_status_col('*', attr);
-	}
+		init_status_col(base_pos, line_position(), edisp_pos, new_pos);
 #endif
 
 	if (squeeze && blankline)
@@ -258,9 +343,7 @@ get_forw_line:
 	return (new_pos);
 }
 
-	public POSITION
-forw_line(curr_pos)
-	POSITION curr_pos;
+public POSITION forw_line(POSITION curr_pos)
 {
 
 	return forw_line_seg(curr_pos, (chop_line() || hshift > 0), TRUE, FALSE);
@@ -273,15 +356,18 @@ forw_line(curr_pos)
  * a line.  The new position is the position of the first character
  * of the PREVIOUS line.  The line obtained is the one starting at new_pos.
  */
-	public POSITION
-back_line(curr_pos)
-	POSITION curr_pos;
+public POSITION back_line(POSITION curr_pos)
 {
-	POSITION new_pos, begin_new_pos, base_pos;
+	POSITION base_pos;
+	POSITION new_pos;
+	POSITION edisp_pos;
+	POSITION begin_new_pos;
 	int c;
 	int endline;
 	int chopped;
 	int backchars;
+	POSITION wrap_pos;
+	int skipped_leading;
 
 get_back_line:
 	if (curr_pos == NULL_POSITION || curr_pos <= ch_zero())
@@ -383,11 +469,13 @@ get_back_line:
 	prewind();
 	plinestart(new_pos);
     loop:
+	wrap_pos = NULL_POSITION;
+	skipped_leading = FALSE;
 	begin_new_pos = new_pos;
 	(void) ch_seek(new_pos);
 	chopped = FALSE;
 
-	do
+	for (;;)
 	{
 		c = ch_forw_get();
 		if (c == EOI || ABORT_SIGS())
@@ -405,6 +493,7 @@ get_back_line:
 				goto shift;
 			}
 			endline = TRUE;
+			edisp_pos = new_pos;
 			break;
 		}
 		backchars = pappend(c, ch_tell()-1);
@@ -420,18 +509,65 @@ get_back_line:
 				endline = TRUE;
 				chopped = TRUE;
 				quit_if_one_screen = FALSE;
+				edisp_pos = new_pos;
 				break;
 			}
 		shift:
-			pshift_all();
-			while (backchars-- > 0)
+			if (!wordwrap)
 			{
-				(void) ch_back_get();
-				new_pos--;
+				pshift_all();
+				new_pos -= backchars;
+			} else
+			{
+				if (c == ' ' || c == '\t')
+				{
+					for (;;)
+					{
+						c = ch_forw_get();
+						if (c == ' ' || c == '\t')
+							new_pos++;
+						else
+						{
+							if (c == '\r')
+							{
+								c = ch_forw_get();
+								if (c == '\n')
+									new_pos++;
+							}
+							if (c == '\n')
+								new_pos++;
+							break;
+						}
+					}
+					if (new_pos >= curr_pos)
+						break;
+					pshift_all();
+				} else
+				{
+					pshift_all();
+					if (wrap_pos == NULL_POSITION)
+						new_pos -= backchars;
+					else
+						new_pos = wrap_pos;
+				}
 			}
 			goto loop;
 		}
-	} while (new_pos < curr_pos);
+		if (wordwrap)
+		{
+			if (c == ' ' || c == '\t')
+			{
+				if (skipped_leading)
+					wrap_pos = new_pos;
+			} else
+				skipped_leading = TRUE;
+		}
+		if (new_pos >= curr_pos)
+		{
+			edisp_pos = new_pos;
+			break;
+		}
+	}
 
 	pdone(endline, chopped, 0);
 
@@ -445,13 +581,8 @@ get_back_line:
 		curr_pos = begin_new_pos;
 		goto get_back_line;
 	}
-
-	if (status_col && curr_pos > 0)
-	{
-		int attr = is_hilited_attr(base_pos, curr_pos-1, 1, NULL);
-		if (attr)
-			set_status_col('*', attr);
-	}
+	if (status_col)
+		init_status_col(base_pos, line_position(), edisp_pos, new_pos);
 #endif
 
 	return (begin_new_pos);
@@ -460,9 +591,7 @@ get_back_line:
 /*
  * Set attnpos.
  */
-	public void
-set_attnpos(pos)
-	POSITION pos;
+public void set_attnpos(POSITION pos)
 {
 	int c;