Add multiple color schemes and key bindings to change them

This commits adds these color schemes:

- the default (dark) st color scheme
- the default (dark) alacritty color scheme
- One Half (dark & light)
- Solarized (dark & light)
- Gruvbox (dark & light)

Select one with Alt+1..8.
Select the next one with Alt+0.
Select the previous one with Ctrl+Alt+0.

config.def.h

@@ -93,46 +93,87 @@ char *termname = "st-256color";
  */
 unsigned int tabspaces = 8;
 
-/* Terminal colors (16 first used in escape sequence) */
+typedef struct {
-static const char *colorname[] = {
+	const char* const colors[258]; /* terminal colors */
-	/* 8 normal colors */
+	unsigned int fg;               /* foreground */
-	"black",
+	unsigned int bg;               /* background */
-	"red3",
+	unsigned int cs;               /* cursor */
-	"green3",
+	unsigned int rcs;              /* reverse cursor */
-	"yellow3",
+} ColorScheme;
-	"blue2",
+/*
-	"magenta3",
+ * Terminal colors (16 first used in escape sequence,
-	"cyan3",
+ * 2 last for custom cursor color),
-	"gray90",
+ * foreground, background, cursor, reverse cursor
+ */
+static const ColorScheme schemes[] = {
+	// st (dark)
+	{{"black", "red3", "green3", "yellow3",
+	  "blue2", "magenta3", "cyan3", "gray90",
+	  "gray50", "red", "green", "yellow",
+	  "#5c5cff", "magenta", "cyan", "white",
+	  [256]="#cccccc", "#555555"}, 7, 0, 256, 257},
 
-	/* 8 bright colors */
+	// Alacritty (dark)
-	"gray50",
+	{{"#1d1f21", "#cc6666", "#b5bd68", "#f0c674",
-	"red",
+	  "#81a2be", "#b294bb", "#8abeb7", "#c5c8c6",
-	"green",
+	  "#666666", "#d54e53", "#b9ca4a", "#e7c547",
-	"yellow",
+	  "#7aa6da", "#c397d8", "#70c0b1", "#eaeaea",
-	"#5c5cff",
+	  [256]="#cccccc", "#555555"}, 7, 0, 256, 257},
-	"magenta",
-	"cyan",
-	"white",
 
-	[255] = 0,
+	// One Half dark
+	{{"#282c34", "#e06c75", "#98c379", "#e5c07b",
+	  "#61afef", "#c678dd", "#56b6c2", "#dcdfe4",
+	  "#282c34", "#e06c75", "#98c379", "#e5c07b",
+	  "#61afef", "#c678dd", "#56b6c2", "#dcdfe4",
+	  [256]="#cccccc", "#555555"}, 7, 0, 256, 257},
 
-	/* more colors can be added after 255 to use with DefaultXX */
+	// One Half light
-	"#cccccc",
+	{{"#fafafa", "#e45649", "#50a14f", "#c18401",
-	"#555555",
+      "#0184bc", "#a626a4", "#0997b3", "#383a42",
-	"gray90", /* default foreground colour */
+	  "#fafafa", "#e45649", "#50a14f", "#c18401",
-	"black", /* default background colour */
+	  "#0184bc", "#a626a4", "#0997b3", "#383a42",
+	  [256]="#cccccc", "#555555"}, 7, 0, 256, 257},
+
+	// Solarized dark
+	{{"#073642", "#dc322f", "#859900", "#b58900",
+	  "#268bd2", "#d33682", "#2aa198", "#eee8d5",
+	  "#002b36", "#cb4b16", "#586e75", "#657b83",
+	  "#839496", "#6c71c4", "#93a1a1", "#fdf6e3",
+	  [256]="#93a1a1", "#fdf6e3"}, 12, 8, 256, 257},
+
+	// Solarized light
+	{{"#eee8d5", "#dc322f", "#859900", "#b58900",
+	  "#268bd2", "#d33682", "#2aa198", "#073642",
+	  "#fdf6e3", "#cb4b16", "#93a1a1", "#839496",
+	  "#657b83", "#6c71c4", "#586e75", "#002b36",
+	  [256]="#586e75", "#002b36"}, 12, 8, 256, 257},
+
+	// Gruvbox dark
+	{{"#282828", "#cc241d", "#98971a", "#d79921",
+	  "#458588", "#b16286", "#689d6a", "#a89984",
+	  "#928374", "#fb4934", "#b8bb26", "#fabd2f",
+	  "#83a598", "#d3869b", "#8ec07c", "#ebdbb2",
+	  [256]="#ebdbb2", "#555555"}, 15, 0, 256, 257},
+
+	// Gruvbox light
+	{{"#fbf1c7", "#cc241d", "#98971a", "#d79921",
+	  "#458588", "#b16286", "#689d6a", "#7c6f64",
+	  "#928374", "#9d0006", "#79740e", "#b57614",
+	  "#076678", "#8f3f71", "#427b58", "#3c3836",
+	  [256]="#3c3836", "#555555"}, 15, 0, 256, 257},
 };
 
+static const char * const * colorname;
+int colorscheme = 0;
 
 /*
  * Default colors (colorname index)
  * foreground, background, cursor, reverse cursor
  */
-unsigned int defaultfg = 258;
+unsigned int defaultfg;
-unsigned int defaultbg = 259;
+unsigned int defaultbg;
-unsigned int defaultcs = 256;
+unsigned int defaultcs;
-static unsigned int defaultrcs = 257;
+static unsigned int defaultrcs;
 
 /*
  * Default shape of cursor
@@ -201,6 +242,17 @@ static Shortcut shortcuts[] = {
 	{ TERMMOD,              XK_Y,           selpaste,       {.i =  0} },
 	{ ShiftMask,            XK_Insert,      selpaste,       {.i =  0} },
 	{ TERMMOD,              XK_Num_Lock,    numlock,        {.i =  0} },
+	{ MODKEY,               XK_1,           selectscheme,   {.i =  0} },
+	{ MODKEY,               XK_2,           selectscheme,   {.i =  1} },
+	{ MODKEY,               XK_3,           selectscheme,   {.i =  2} },
+	{ MODKEY,               XK_4,           selectscheme,   {.i =  3} },
+	{ MODKEY,               XK_5,           selectscheme,   {.i =  4} },
+	{ MODKEY,               XK_6,           selectscheme,   {.i =  5} },
+	{ MODKEY,               XK_7,           selectscheme,   {.i =  6} },
+	{ MODKEY,               XK_8,           selectscheme,   {.i =  7} },
+	{ MODKEY,               XK_9,           selectscheme,   {.i =  8} },
+	{ MODKEY,               XK_0,           nextscheme,     {.i = +1} },
+	{ MODKEY|ControlMask,   XK_0,           nextscheme,     {.i = -1} },
 };
 
 /*

st.c

@@ -2171,6 +2171,28 @@ tstrsequence(uchar c)
 	term.esc |= ESC_STR;
 }
 
+void
+tupdatebgcolor(int oldbg, int newbg)
+{
+	for (int y = 0; y < term.row; y++) {
+		for (int x = 0; x < term.col; x++) {
+			if (term.line[y][x].bg == oldbg)
+				term.line[y][x].bg = newbg;
+		}
+	}
+}
+
+void
+tupdatefgcolor(int oldfg, int newfg)
+{
+	for (int y = 0; y < term.row; y++) {
+		for (int x = 0; x < term.col; x++) {
+			if (term.line[y][x].fg == oldfg)
+				term.line[y][x].fg = newfg;
+		}
+	}
+}
+
 void
 tcontrolcode(uchar ascii)
 {

st.h

@@ -90,6 +90,8 @@ int tattrset(int);
 void tnew(int, int);
 void tresize(int, int);
 void tsetdirtattr(int);
+void tupdatebgcolor(int, int);
+void tupdatefgcolor(int, int);
 void ttyhangup(void);
 int ttynew(const char *, char *, const char *, char **);
 size_t ttyread(void);

x.c

@@ -59,6 +59,8 @@ static void zoom(const Arg *);
 static void zoomabs(const Arg *);
 static void zoomreset(const Arg *);
 static void ttysend(const Arg *);
+static void nextscheme(const Arg *);
+static void selectscheme(const Arg *);
 
 /* config.h for applying patches and the configuration. */
 #include "config.h"
@@ -185,6 +187,7 @@ static void mousesel(XEvent *, int);
 static void mousereport(XEvent *);
 static char *kmap(KeySym, uint);
 static int match(uint, uint);
+static void updatescheme(void);
 
 static void run(void);
 static void usage(void);
@@ -801,7 +804,7 @@ xloadcols(void)
 		for (cp = dc.col; cp < &dc.col[dc.collen]; ++cp)
 			XftColorFree(xw.dpy, xw.vis, xw.cmap, cp);
 	} else {
-		dc.collen = MAX(LEN(colorname), 256);
+		dc.collen = 258;
 		dc.col = xmalloc(dc.collen * sizeof(Color));
 	}
 
@@ -2027,6 +2030,47 @@ usage(void)
 	    " [stty_args ...]\n", argv0, argv0);
 }
 
+void
+nextscheme(const Arg *arg)
+{
+	colorscheme += arg->i;
+	if (colorscheme >= (int)LEN(schemes))
+		colorscheme = 0;
+	else if (colorscheme < 0)
+		colorscheme = LEN(schemes) - 1;
+	updatescheme();
+}
+
+void
+selectscheme(const Arg *arg)
+{
+	if (BETWEEN(arg->i, 0, LEN(schemes)-1)) {
+		colorscheme = arg->i;
+		updatescheme();
+	}
+}
+
+void
+updatescheme(void)
+{
+	int oldbg, oldfg;
+
+	oldbg = defaultbg;
+	oldfg = defaultfg;
+	colorname = schemes[colorscheme].colors;
+	defaultbg = schemes[colorscheme].bg;
+	defaultfg = schemes[colorscheme].fg;
+	defaultcs = schemes[colorscheme].cs;
+	defaultrcs = schemes[colorscheme].rcs;
+	xloadcols();
+	if (defaultbg != oldbg)
+		tupdatebgcolor(oldbg, defaultbg);
+	if (defaultfg != oldfg)
+		tupdatefgcolor(oldfg, defaultfg);
+	cresize(win.w, win.h);
+	redraw();
+}
+
 int
 main(int argc, char *argv[])
 {
@@ -2079,6 +2123,12 @@ main(int argc, char *argv[])
 	} ARGEND;
 
 run:
+	colorname = schemes[colorscheme].colors;
+	defaultbg = schemes[colorscheme].bg;
+	defaultfg = schemes[colorscheme].fg;
+	defaultcs = schemes[colorscheme].cs;
+	defaultrcs = schemes[colorscheme].rcs;
+
 	if (argc > 0) /* eat all remaining arguments */
 		opt_cmd = argv;