Add --no-number-headers option.

NEWS

@@ -14,6 +14,8 @@
 
 * Add the --header option.
 
+* Add the --no-number-headers option.
+
 * Add the --status-line option.
 
 * Fix display of multibyte and double-width chars in prompt.

command.c

@@ -48,6 +48,7 @@ extern IFILE curr_ifile;
 extern void *ml_search;
 extern void *ml_examine;
 extern int wheel_lines;
+extern int header_lines;
 #if SHELL_ESCAPE || PIPEC
 extern void *ml_shell;
 #endif

forwback.c

@@ -136,7 +136,7 @@ forw_line_pfx(pos, pfx, skipeol)
  int save_sc_width = sc_width;
  int save_auto_wrap = auto_wrap;
  int save_hshift = hshift;
- /* Set fake sc_width to force only pfx chars to be read. */
+ /* Set fake sc_width to force only pfx chars to be read. */
  sc_width = pfx + line_pfx_width();
  auto_wrap = 0;
  hshift = 0;
@@ -165,6 +165,12 @@ overlay_header(VOID_PARAM)
  for (ln = 0; ln < header_lines; ++ln)
  {
  pos = forw_line(pos);
+ /*
+ * Underline last line of header, unless 
+ * we are at beginning of file.
+ */
+ if (ln+1 == header_lines && position(0) != ch_zero())
+ punderline();
  clear_eol();
  put_line();
  }
@@ -184,7 +190,7 @@ overlay_header(VOID_PARAM)
  putchr('\n');
  else 
  {
- /* Need skipeol for all header lines except the last one. */
+ /* Need skipeol for all header lines except the last one. */
  pos = forw_line_pfx(pos, header_cols, ln+1 < header_lines);
  put_line();
  }
@@ -364,6 +370,18 @@ forw(n, pos, force, only_last, nblank)
  forw_prompt = 1;
  }
 
+ if (header_lines > 0)
+ {
+ /*
+ * Don't allow ch_zero to appear on screen except at top of screen.
+ * Otherwise duplicate header lines may be displayed.
+ */
+ if (onscreen(ch_zero()) > 0)
+ {
+ jump_loc(ch_zero(), 0); /* {{ yuck }} */
+ return;
+ }
+ }
  if (nlines == 0 && !ignore_eoi)
  eof_bell();
  else if (do_repaint)

less.hlp

@@ -221,6 +221,8 @@
  Don't send termcap keypad init/deinit strings.
  --no-histdups
  Remove duplicates from command history.
+ --no-number-headers
+ Don't give line numbers to header lines.
  --rscroll=C
  Set the character used to mark truncated lines.
  --save-marks

less.nro.VER

@@ -1116,6 +1116,8 @@ even if the rest of the line is scrolled horizontally.
 If either N or M is zero, 
 .I less
 stops displaying header lines or columns, respectively.
+(Note that it may be neccessary to change the setting of the \-j option
+to ensure that the target line is not obscured by the header line(s).)
 .IP "\-\-incsearch"
 Subsequent search commands will be "incremental"; that is,
 .I less
@@ -1149,6 +1151,9 @@ file name is typed in, and the same string is already in the history list,
 the existing copy is removed from the history list before the new one is added.
 Thus, a given string will appear only once in the history list.
 Normally, a string may appear multiple times.
+.IP "\-\-no-number-headers"
+Header lines (defined via the \-\-header option) are not assigned line numbers.
+Line number 1 is assigned to the first line after any header lines.
 .IP "\-\-rscroll"
 This option changes the character used to mark truncated lines.
 It may begin with a two-character attribute indicator like LESSBINFMT does.

line.c

@@ -331,8 +331,14 @@ plinestart(pos)
  char buf[INT_STRLEN_BOUND(linenum) + 2];
  int len;
 
- linenumtoa(linenum, buf);
- len = (int) strlen(buf);
+ linenum = vlinenum(linenum);
+ if (linenum == 0)
+ len = 0;
+ else
+ {
+ linenumtoa(linenum, buf);
+ len = (int) strlen(buf);
+ }
  for (i = 0; i < linenum_width - len; i++)
  add_pfx(' ', AT_NORMAL);
  for (i = 0; i < len; i++)
@@ -1260,7 +1266,19 @@ pdone(endline, chopped, forw)
 }
 
 /*
- *
+ * Underline the line in the line buffer.
+ */
+ public void
+punderline(VOID_PARAM)
+{
+ int i;
+
+ for (i = linebuf.print; i < linebuf.end; i++)
+ linebuf.attr[i] |= AT_UNDERLINE;
+}
+
+/*
+ * Set the char to be displayed in the status column.
  */
  public void
 set_status_col(c, attr)

linenum.c

@@ -68,6 +68,8 @@ extern int linenums;
 extern int sigs;
 extern int sc_height;
 extern int screen_trashed;
+extern int header_lines;
+extern int nonum_headers;
 
 /*
  * Initialize the line number structures.
@@ -484,11 +486,24 @@ scan_eof(VOID_PARAM)
  ierror("Determining length of file", NULL_PARG);
  while (pos != NULL_POSITION)
  {
- /* For efficiency, only add one every 256 line numbers. */
- if ((linenum++ % 256) == 0)
- add_lnum(linenum, pos);
+ /* For efficiency, only add one every 256 line numbers. */
+ if ((linenum++ % 256) == 0)
+ add_lnum(linenum, pos);
  pos = forw_raw_line(pos, (char **)NULL, (int *)NULL);
  if (ABORT_SIGS())
  break;
  }
 }
+
+/*
+ * Return a line number adjusted for display
+ * (handles the --no-number-headers option).
+ */
+ public LINENUM
+vlinenum(linenum)
+ LINENUM linenum;
+{
+ if (nonum_headers)
+ linenum = (linenum < header_lines) ? 0 : linenum - header_lines;
+ return linenum;
+}

optfunc.c

@@ -1082,6 +1082,6 @@ get_swindow(VOID_PARAM)
 {
  if (swindow > 0)
  return (swindow);
- return (sc_height + swindow);
+ return (sc_height - header_lines + swindow);
 }
 

opttbl.c

@@ -67,6 +67,7 @@ public int want_filesize; /* Scan to EOF if necessary to get file size */
 public int status_line; /* Highlight entire marked lines */
 public int header_lines; /* Freeze header lines at top of screen */
 public int header_cols; /* Freeze header columns at left of screen */
+public int nonum_headers; /* Don't give headers line numbers */
 #if HILITE_SEARCH
 public int hilite_search; /* Highlight matched search patterns? */
 #endif
@@ -144,6 +145,7 @@ static struct optname use_color_optname = { "use-color", NULL };
 static struct optname want_filesize_optname = { "file-size", NULL };
 static struct optname status_line_optname = { "status-line", NULL };
 static struct optname header_optname = { "header", NULL };
+static struct optname nonum_headers_optname = { "no-number-headers", NULL };
 #if LESSTEST
 static struct optname ttyin_name_optname = { "tty", NULL };
 static struct optname rstat_optname = { "rstat", NULL };
@@ -583,6 +585,14 @@ static struct loption option[] =
  NULL
  }
  },
+ { OLETTER_NONE, &nonum_headers_optname,
+ BOOL|REPAINT, 0, &nonum_headers, NULL,
+ {
+ "Number header lines",
+ "Don't number header lines",
+ NULL
+ }
+ },
 #if LESSTEST
  { OLETTER_NONE, &ttyin_name_optname,
  STRING|NO_TOGGLE, 0, NULL, opt_ttyin_name,

position.c

@@ -25,6 +25,7 @@ static POSITION *table = NULL; /* The position table */
 static int table_size = 0;
 
 extern int sc_width, sc_height;
+extern int header_lines;
 
 /*
  * Return the starting file position of a line displayed on the screen.

prompt.c

@@ -29,6 +29,7 @@ extern int hshift;
 extern int sc_height;
 extern int jump_sline;
 extern int less_is_more;
+extern int header_lines;
 extern IFILE curr_ifile;
 #if EDITOR
 extern char *editor;
@@ -260,7 +261,7 @@ protochar(c, where, iseditproto)
  char *s;
 
 #undef PAGE_NUM
-#define PAGE_NUM(linenum) ((((linenum) - 1) / (sc_height - 1)) + 1)
+#define PAGE_NUM(linenum) ((((linenum) - 1) / (sc_height - header_lines - 1)) + 1)
 
  switch (c)
  {
@@ -325,7 +326,7 @@ protochar(c, where, iseditproto)
  case 'l': /* Current line number */
  linenum = currline(where);
  if (linenum != 0)
- ap_linenum(linenum);
+ ap_linenum(vlinenum(linenum));
  else
  ap_quest();
  break;
@@ -335,7 +336,7 @@ protochar(c, where, iseditproto)
  (linenum = find_linenum(len)) <= 0)
  ap_quest();
  else
- ap_linenum(linenum-1);
+ ap_linenum(vlinenum(linenum-1));
  break;
  case 'm': /* Number of files */
 #if TAGS

version.c

@@ -934,7 +934,7 @@ v590 6/3/21 Fix non-autoconf Makefiles.
 v591 8/8/21 Use \kB for backspace key in lesskey; add more \k codes;
  handle multibyte chars in prompt.
 v592 8/24/21 Add --status-line option; limit use of /proc kludge; add --header.
-v593
+v593 Add header columns, --no-number-headers.
 */
 
 char version[] = "593x";