--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/diagnostic-color.c	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,321 @@
+/* Output colorization.
+   Copyright (C) 2011-2017 Free Software Foundation, Inc.
+
+   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, or (at your option)
+   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, write to the Free Software
+   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA
+   02110-1301, USA.  */
+
+#include "config.h"
+#include "system.h"
+#include "diagnostic-color.h"
+
+#ifdef __MINGW32__
+#  include <windows.h>
+#endif
+
+/* Select Graphic Rendition (SGR, "\33[...m") strings.  */
+/* Also Erase in Line (EL) to Right ("\33[K") by default.  */
+/*    Why have EL to Right after SGR?
+	 -- The behavior of line-wrapping when at the bottom of the
+	    terminal screen and at the end of the current line is often
+	    such that a new line is introduced, entirely cleared with
+	    the current background color which may be different from the
+	    default one (see the boolean back_color_erase terminfo(5)
+	    capability), thus scrolling the display by one line.
+	    The end of this new line will stay in this background color
+	    even after reverting to the default background color with
+	    "\33[m', unless it is explicitly cleared again with "\33[K"
+	    (which is the behavior the user would instinctively expect
+	    from the whole thing).  There may be some unavoidable
+	    background-color flicker at the end of this new line because
+	    of this (when timing with the monitor's redraw is just right).
+	 -- The behavior of HT (tab, "\t") is usually the same as that of
+	    Cursor Forward Tabulation (CHT) with a default parameter
+	    of 1 ("\33[I"), i.e., it performs pure movement to the next
+	    tab stop, without any clearing of either content or screen
+	    attributes (including background color); try
+	       printf 'asdfqwerzxcv\rASDF\tZXCV\n'
+	    in a bash(1) shell to demonstrate this.  This is not what the
+	    user would instinctively expect of HT (but is ok for CHT).
+	    The instinctive behavior would include clearing the terminal
+	    cells that are skipped over by HT with blank cells in the
+	    current screen attributes, including background color;
+	    the boolean dest_tabs_magic_smso terminfo(5) capability
+	    indicates this saner behavior for HT, but only some rare
+	    terminals have it (although it also indicates a special
+	    glitch with standout mode in the Teleray terminal for which
+	    it was initially introduced).  The remedy is to add "\33K"
+	    after each SGR sequence, be it START (to fix the behavior
+	    of any HT after that before another SGR) or END (to fix the
+	    behavior of an HT in default background color that would
+	    follow a line-wrapping at the bottom of the screen in another
+	    background color, and to complement doing it after START).
+	    Piping GCC's output through a pager such as less(1) avoids
+	    any HT problems since the pager performs tab expansion.
+
+      Generic disadvantages of this remedy are:
+	 -- Some very rare terminals might support SGR but not EL (nobody
+	    will use "gcc -fdiagnostics-color" on a terminal that does not
+	    support SGR in the first place).
+	 -- Having these extra control sequences might somewhat complicate
+	    the task of any program trying to parse "gcc -fdiagnostics-color"
+	    output in order to extract structuring information from it.
+      A specific disadvantage to doing it after SGR START is:
+	 -- Even more possible background color flicker (when timing
+	    with the monitor's redraw is just right), even when not at the
+	    bottom of the screen.
+      There are no additional disadvantages specific to doing it after
+      SGR END.
+
+      It would be impractical for GCC to become a full-fledged
+      terminal program linked against ncurses or the like, so it will
+      not detect terminfo(5) capabilities.  */
+#define COLOR_SEPARATOR		";"
+#define COLOR_NONE		"00"
+#define COLOR_BOLD		"01"
+#define COLOR_UNDERSCORE	"04"
+#define COLOR_BLINK		"05"
+#define COLOR_REVERSE		"07"
+#define COLOR_FG_BLACK		"30"
+#define COLOR_FG_RED		"31"
+#define COLOR_FG_GREEN		"32"
+#define COLOR_FG_YELLOW		"33"
+#define COLOR_FG_BLUE		"34"
+#define COLOR_FG_MAGENTA	"35"
+#define COLOR_FG_CYAN		"36"
+#define COLOR_FG_WHITE		"37"
+#define COLOR_BG_BLACK		"40"
+#define COLOR_BG_RED		"41"
+#define COLOR_BG_GREEN		"42"
+#define COLOR_BG_YELLOW		"43"
+#define COLOR_BG_BLUE		"44"
+#define COLOR_BG_MAGENTA	"45"
+#define COLOR_BG_CYAN		"46"
+#define COLOR_BG_WHITE		"47"
+#define SGR_START		"\33["
+#define SGR_END			"m\33[K"
+#define SGR_SEQ(str)		SGR_START str SGR_END
+#define SGR_RESET		SGR_SEQ("")
+
+
+/* The context and logic for choosing default --color screen attributes
+   (foreground and background colors, etc.) are the following.
+      -- There are eight basic colors available, each with its own
+	 nominal luminosity to the human eye and foreground/background
+	 codes (black [0 %, 30/40], blue [11 %, 34/44], red [30 %, 31/41],
+	 magenta [41 %, 35/45], green [59 %, 32/42], cyan [70 %, 36/46],
+	 yellow [89 %, 33/43], and white [100 %, 37/47]).
+      -- Sometimes, white as a background is actually implemented using
+	 a shade of light gray, so that a foreground white can be visible
+	 on top of it (but most often not).
+      -- Sometimes, black as a foreground is actually implemented using
+	 a shade of dark gray, so that it can be visible on top of a
+	 background black (but most often not).
+      -- Sometimes, more colors are available, as extensions.
+      -- Other attributes can be selected/deselected (bold [1/22],
+	 underline [4/24], standout/inverse [7/27], blink [5/25], and
+	 invisible/hidden [8/28]).  They are sometimes implemented by
+	 using colors instead of what their names imply; e.g., bold is
+	 often achieved by using brighter colors.  In practice, only bold
+	 is really available to us, underline sometimes being mapped by
+	 the terminal to some strange color choice, and standout best
+	 being left for use by downstream programs such as less(1).
+      -- We cannot assume that any of the extensions or special features
+	 are available for the purpose of choosing defaults for everyone.
+      -- The most prevalent default terminal backgrounds are pure black
+	 and pure white, and are not necessarily the same shades of
+	 those as if they were selected explicitly with SGR sequences.
+	 Some terminals use dark or light pictures as default background,
+	 but those are covered over by an explicit selection of background
+	 color with an SGR sequence; their users will appreciate their
+	 background pictures not be covered like this, if possible.
+      -- Some uses of colors attributes is to make some output items
+	 more understated (e.g., context lines); this cannot be achieved
+	 by changing the background color.
+      -- For these reasons, the GCC color defaults should strive not
+	 to change the background color from its default, unless it's
+	 for a short item that should be highlighted, not understated.
+      -- The GCC foreground color defaults (without an explicitly set
+	 background) should provide enough contrast to be readable on any
+	 terminal with either a black (dark) or white (light) background.
+	 This only leaves red, magenta, green, and cyan (and their bold
+	 counterparts) and possibly bold blue.  */
+/* Default colors. The user can overwrite them using environment
+   variable GCC_COLORS.  */
+struct color_cap
+{
+  const char *name;
+  const char *val;
+  unsigned char name_len;
+  bool free_val;
+};
+
+/* For GCC_COLORS.  */
+static struct color_cap color_dict[] =
+{
+  { "error", SGR_SEQ (COLOR_BOLD COLOR_SEPARATOR COLOR_FG_RED), 5, false },
+  { "warning", SGR_SEQ (COLOR_BOLD COLOR_SEPARATOR COLOR_FG_MAGENTA),
+	       7, false },
+  { "note", SGR_SEQ (COLOR_BOLD COLOR_SEPARATOR COLOR_FG_CYAN), 4, false },
+  { "range1", SGR_SEQ (COLOR_FG_GREEN), 6, false },
+  { "range2", SGR_SEQ (COLOR_FG_BLUE), 6, false },
+  { "locus", SGR_SEQ (COLOR_BOLD), 5, false },
+  { "quote", SGR_SEQ (COLOR_BOLD), 5, false },
+  { "fixit-insert", SGR_SEQ (COLOR_FG_GREEN), 12, false },
+  { "fixit-delete", SGR_SEQ (COLOR_FG_RED), 12, false },
+  { "diff-filename", SGR_SEQ (COLOR_BOLD), 13, false },
+  { "diff-hunk", SGR_SEQ (COLOR_FG_CYAN), 9, false },
+  { "diff-delete", SGR_SEQ (COLOR_FG_RED), 11, false },
+  { "diff-insert", SGR_SEQ (COLOR_FG_GREEN), 11, false },
+  { "type-diff", SGR_SEQ (COLOR_BOLD COLOR_SEPARATOR COLOR_FG_GREEN), 9, false },
+  { NULL, NULL, 0, false }
+};
+
+const char *
+colorize_start (bool show_color, const char *name, size_t name_len)
+{
+  struct color_cap const *cap;
+
+  if (!show_color)
+    return "";
+
+  for (cap = color_dict; cap->name; cap++)
+    if (cap->name_len == name_len
+	&& memcmp (cap->name, name, name_len) == 0)
+      break;
+  if (cap->name == NULL)
+    return "";
+
+  return cap->val;
+}
+
+const char *
+colorize_stop (bool show_color)
+{
+  return show_color ? SGR_RESET : "";
+}
+
+/* Parse GCC_COLORS.  The default would look like:
+   GCC_COLORS='error=01;31:warning=01;35:note=01;36:\
+   range1=32:range2=34:locus=01:quote=01:\
+   fixit-insert=32:fixit-delete=31:'\
+   diff-filename=01:diff-hunk=32:diff-delete=31:diff-insert=32:\
+   type-diff=01;32'
+   No character escaping is needed or supported.  */
+static bool
+parse_gcc_colors (void)
+{
+  const char *p, *q, *name, *val;
+  char *b;
+  size_t name_len = 0, val_len = 0;
+
+  p = getenv ("GCC_COLORS"); /* Plural! */
+  if (p == NULL)
+    return true;
+  if (*p == '\0')
+    return false;
+
+  name = q = p;
+  val = NULL;
+  /* From now on, be well-formed or you're gone.  */
+  for (;;)
+    if (*q == ':' || *q == '\0')
+      {
+	struct color_cap *cap;
+
+	if (val)
+	  val_len = q - val;
+	else
+	  name_len = q - name;
+	/* Empty name without val (empty cap)
+	   won't match and will be ignored.  */
+	for (cap = color_dict; cap->name; cap++)
+	  if (cap->name_len == name_len
+	      && memcmp (cap->name, name, name_len) == 0)
+	    break;
+	/* If name unknown, go on for forward compatibility.  */
+	if (cap->val && val)
+	  {
+	    if (cap->free_val)
+	      free (CONST_CAST (char *, cap->val));
+	    b = XNEWVEC (char, val_len + sizeof (SGR_SEQ ("")));
+	    memcpy (b, SGR_START, strlen (SGR_START));
+	    memcpy (b + strlen (SGR_START), val, val_len);
+	    memcpy (b + strlen (SGR_START) + val_len, SGR_END,
+		    sizeof (SGR_END));
+	    cap->val = (const char *) b;
+	    cap->free_val = true;
+	  }
+	if (*q == '\0')
+	  return true;
+	name = ++q;
+	val = NULL;
+      }
+    else if (*q == '=')
+      {
+	if (q == name || val)
+	  return true;
+
+	name_len = q - name;
+	val = ++q; /* Can be the empty string.  */
+      }
+    else if (val == NULL)
+      q++; /* Accumulate name.  */
+    else if (*q == ';' || (*q >= '0' && *q <= '9'))
+      q++; /* Accumulate val.  Protect the terminal from being sent
+	      garbage.  */
+    else
+      return true;
+}
+
+/* Return true if we should use color when in auto mode, false otherwise. */
+static bool
+should_colorize (void)
+{
+#ifdef __MINGW32__
+  /* For consistency reasons, one should check the handle returned by
+     _get_osfhandle(_fileno(stderr)) because the function
+     pp_write_text_to_stream() in pretty-print.c calls fputs() on
+     that stream.  However, the code below for non-Windows doesn't seem
+     to care about it either...  */
+  HANDLE h;
+  DWORD m;
+
+  h = GetStdHandle (STD_ERROR_HANDLE);
+  return (h != INVALID_HANDLE_VALUE) && (h != NULL)
+	  && GetConsoleMode (h, &m);
+#else
+  char const *t = getenv ("TERM");
+  return t && strcmp (t, "dumb") != 0 && isatty (STDERR_FILENO);
+#endif
+}
+
+bool
+colorize_init (diagnostic_color_rule_t rule)
+{
+  switch (rule)
+    {
+    case DIAGNOSTICS_COLOR_NO:
+      return false;
+    case DIAGNOSTICS_COLOR_YES:
+      return parse_gcc_colors ();
+    case DIAGNOSTICS_COLOR_AUTO:
+      if (should_colorize ())
+	return parse_gcc_colors ();
+      else
+	return false;
+    default:
+      gcc_unreachable ();
+    }
+}