From 312809f8838911dabff84d7ad3ccf341307d2b19 Mon Sep 17 00:00:00 2001
From: Eli Zaretskii <eliz@gnu.org>
Date: Sat, 31 Jan 2015 10:47:14 +0200
Subject: [PATCH] Make sure TABs are expanded in TUI windows on MS-Windows.

gdb/
2015-01-31  Eli Zaretskii  <eliz@gnu.org>

	* tui/tui-io.c (tui_expand_tabs): New function.
	(tui_puts, tui_redisplay_readline): Expand TABs into the
	appropriate number of spaces.
	* tui/tui-regs.c: Include tui-io.h.
	(tui_register_format): Call tui_expand_tabs to expand TABs into
	the appropriate number of spaces.
	* tui/tui-io.h: Add prototype for tui_expand_tabs.
---
 gdb/ChangeLog      | 10 ++++++
 gdb/tui/tui-io.c   | 78 +++++++++++++++++++++++++++++++++++++++++++++-
 gdb/tui/tui-io.h   |  3 ++
 gdb/tui/tui-regs.c |  5 ++-
 4 files changed, 94 insertions(+), 2 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 58f5a7b3b7c..51f17145b13 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,13 @@
+2015-01-31  Eli Zaretskii  <eliz@gnu.org>
+
+	* tui/tui-io.c (tui_expand_tabs): New function.
+	(tui_puts, tui_redisplay_readline): Expand TABs into the
+	appropriate number of spaces.
+	* tui/tui-regs.c: Include tui-io.h.
+	(tui_register_format): Call tui_expand_tabs to expand TABs into
+	the appropriate number of spaces.
+	* tui/tui-io.h: Add prototype for tui_expand_tabs.
+
 2015-01-30  Doug Evans  <dje@google.com>
 
 	* NEWS: "info source" command now display producer string if present.
diff --git a/gdb/tui/tui-io.c b/gdb/tui/tui-io.c
index 7e8a3bc0d29..19e9485ea38 100644
--- a/gdb/tui/tui-io.c
+++ b/gdb/tui/tui-io.c
@@ -178,7 +178,20 @@ tui_puts (const char *string)
       else if (tui_skip_line != 1)
         {
           tui_skip_line = -1;
-          waddch (w, c);
+	  /* Expand TABs, since ncurses on MS-Windows doesn't.  */
+	  if (c == '\t')
+	    {
+	      int line, col;
+
+	      getyx (w, line, col);
+	      do
+		{
+		  waddch (w, ' ');
+		  col++;
+		} while ((col % 8) != 0);
+	    }
+	  else
+	    waddch (w, c);
         }
       else if (c == '\n')
         tui_skip_line = -1;
@@ -256,6 +269,16 @@ tui_redisplay_readline (void)
           waddch (w, '^');
           waddch (w, CTRL_CHAR (c) ? UNCTRL (c) : '?');
 	}
+      else if (c == '\t')
+	{
+	  /* Expand TABs, since ncurses on MS-Windows doesn't.  */
+	  getyx (w, line, col);
+	  do
+	    {
+	      waddch (w, ' ');
+	      col++;
+	    } while ((col % 8) != 0);
+	}
       else
 	{
           waddch (w, c);
@@ -724,6 +747,59 @@ tui_getc (FILE *fp)
   return ch;
 }
 
+/* Utility function to expand TABs in a STRING into spaces.  STRING
+   will be displayed starting at column COL, and is assumed to include
+   no newlines.  The returned expanded string is malloc'ed.  */
+
+char *
+tui_expand_tabs (const char *string, int col)
+{
+  int n_adjust;
+  const char *s;
+  char *ret, *q;
+
+  /* 1. How many additional characters do we need?  */
+  for (n_adjust = 0, s = string; s; )
+    {
+      s = strpbrk (s, "\t");
+      if (s)
+	{
+	  col += (s - string) + n_adjust;
+	  /* Adjustment for the next tab stop, minus one for the TAB
+	     we replace with spaces.  */
+	  n_adjust += 8 - (col % 8) - 1;
+	  s++;
+	}
+    }
+
+  /* Allocate the copy.  */
+  ret = q = xmalloc (strlen (string) + n_adjust + 1);
+
+  /* 2. Copy the original string while replacing TABs with spaces.  */
+  for (s = string; s; )
+    {
+      char *s1 = strpbrk (s, "\t");
+      if (s1)
+	{
+	  if (s1 > s)
+	    {
+	      strncpy (q, s, s1 - s);
+	      q += s1 - s;
+	      col += s1 - s;
+	    }
+	  do {
+	    *q++ = ' ';
+	    col++;
+	  } while ((col % 8) != 0);
+	  s1++;
+	}
+      else
+	strcpy (q, s);
+      s = s1;
+    }
+
+  return ret;
+}
 
 /* Cleanup when a resize has occured.
    Returns the character that must be processed.  */
diff --git a/gdb/tui/tui-io.h b/gdb/tui/tui-io.h
index 8f96cfe9e5e..3154eeef982 100644
--- a/gdb/tui/tui-io.h
+++ b/gdb/tui/tui-io.h
@@ -41,6 +41,9 @@ extern int tui_getc (FILE *);
    changed the edited text.  */
 extern void tui_redisplay_readline (void);
 
+/* Expand TABs into spaces.  */
+extern char *tui_expand_tabs (const char *, int);
+
 extern struct ui_out *tui_out;
 extern struct ui_out *tui_old_uiout;
 
diff --git a/gdb/tui/tui-regs.c b/gdb/tui/tui-regs.c
index b523e90afb2..961491f112d 100644
--- a/gdb/tui/tui-regs.c
+++ b/gdb/tui/tui-regs.c
@@ -36,6 +36,7 @@
 #include "tui/tui-wingeneral.h"
 #include "tui/tui-file.h"
 #include "tui/tui-regs.h"
+#include "tui/tui-io.h"
 #include "reggroups.h"
 #include "valprint.h"
 
@@ -693,7 +694,9 @@ tui_register_format (struct frame_info *frame, int regnum)
   if (s && s[1] == 0)
     *s = 0;
 
-  ret = xstrdup (p);
+  /* Expand tabs into spaces, since ncurses on MS-Windows doesn't.  */
+  ret = tui_expand_tabs (p, 0);
+
   do_cleanups (cleanups);
 
   return ret;
-- 
2.30.2