Change so main-pane-width and height can be given as a percentage.

arguments.c

@@ -352,22 +352,29 @@ long long
 args_percentage(struct args *args, u_char ch, long long minval,
     long long maxval, long long curval, char **cause)
 {
-	const char		*errstr;
-	long long 	 	 ll;
+	const char		*value;
 	struct args_entry	*entry;
-	struct args_value	*value;
-	size_t			 valuelen;
-	char			*copy;
 
 	if ((entry = args_find(args, ch)) == NULL) {
 		*cause = xstrdup("missing");
 		return (0);
 	}
-	value = TAILQ_LAST(&entry->values, args_values);
-	valuelen = strlen(value->value);
+	value = TAILQ_LAST(&entry->values, args_values)->value;
+	return (args_string_percentage(value, minval, maxval, curval, cause));
+}
 
-	if (value->value[valuelen - 1] == '%') {
-		copy = xstrdup(value->value);
+/* Convert a string to a number which may be a percentage. */
+long long
+args_string_percentage(const char *value, long long minval, long long maxval,
+    long long curval, char **cause)
+{
+	const char	*errstr;
+	long long 	 ll;
+	size_t		 valuelen = strlen(value);
+	char		*copy;
+
+	if (value[valuelen - 1] == '%') {
+		copy = xstrdup(value);
 		copy[valuelen - 1] = '\0';
 
 		ll = strtonum(copy, 0, 100, &errstr);
@@ -386,7 +393,7 @@ args_percentage(struct args *args, u_char ch, long long minval,
 			return (0);
 		}
 	} else {
-		ll = strtonum(value->value, minval, maxval, &errstr);
+		ll = strtonum(value, minval, maxval, &errstr);
 		if (errstr != NULL) {
 			*cause = xstrdup(errstr);
 			return (0);

layout-set.c

@@ -18,6 +18,7 @@
 
 #include <sys/types.h>
 
+#include <stdlib.h>
 #include <string.h>
 
 #include "tmux.h"
@@ -186,6 +187,8 @@ layout_set_main_h(struct window *w)
 	struct window_pane	*wp;
 	struct layout_cell	*lc, *lcmain, *lcother, *lcchild;
 	u_int			 n, mainh, otherh, sx, sy;
+	char			*cause;
+	const char		*s;
 
 	layout_print_cell(w->layout_root, __func__, 1);
 
@@ -198,8 +201,15 @@ layout_set_main_h(struct window *w)
 	/* Find available height - take off one line for the border. */
 	sy = w->sy - 1;
 
-	/* Get the main pane height and work out the other pane height. */
-	mainh = options_get_number(w->options, "main-pane-height");
+	/* Get the main pane height. */
+	s = options_get_string(w->options, "main-pane-height");
+	mainh = args_string_percentage(s, 0, sy, sy, &cause);
+	if (cause != NULL) {
+		mainh = 24;
+		free(cause);
+	}
+
+	/* Work out the other pane height. */
 	if (mainh + PANE_MINIMUM >= sy) {
 		if (sy <= PANE_MINIMUM + PANE_MINIMUM)
 			mainh = PANE_MINIMUM;
@@ -207,10 +217,12 @@ layout_set_main_h(struct window *w)
 			mainh = sy - PANE_MINIMUM;
 		otherh = PANE_MINIMUM;
 	} else {
-		otherh = options_get_number(w->options, "other-pane-height");
-		if (otherh == 0)
+		s = options_get_string(w->options, "other-pane-height");
+		otherh = args_string_percentage(s, 0, sy, sy, &cause);
+		if (cause != NULL || otherh == 0) {
 			otherh = sy - mainh;
-		else if (otherh > sy || sy - otherh < mainh)
+			free(cause);
+		} else if (otherh > sy || sy - otherh < mainh)
 			otherh = sy - mainh;
 		else
 			mainh = sy - otherh;
@@ -273,6 +285,8 @@ layout_set_main_v(struct window *w)
 	struct window_pane	*wp;
 	struct layout_cell	*lc, *lcmain, *lcother, *lcchild;
 	u_int			 n, mainw, otherw, sx, sy;
+	char			*cause;
+	const char		*s;
 
 	layout_print_cell(w->layout_root, __func__, 1);
 
@@ -285,8 +299,15 @@ layout_set_main_v(struct window *w)
 	/* Find available width - take off one line for the border. */
 	sx = w->sx - 1;
 
-	/* Get the main pane width and work out the other pane width. */
-	mainw = options_get_number(w->options, "main-pane-width");
+	/* Get the main pane width. */
+	s = options_get_string(w->options, "main-pane-width");
+	mainw = args_string_percentage(s, 0, sx, sx, &cause);
+	if (cause != NULL) {
+		mainw = 80;
+		free(cause);
+	}
+
+	/* Work out the other pane width. */
 	if (mainw + PANE_MINIMUM >= sx) {
 		if (sx <= PANE_MINIMUM + PANE_MINIMUM)
 			mainw = PANE_MINIMUM;
@@ -294,10 +315,12 @@ layout_set_main_v(struct window *w)
 			mainw = sx - PANE_MINIMUM;
 		otherw = PANE_MINIMUM;
 	} else {
-		otherw = options_get_number(w->options, "other-pane-width");
-		if (otherw == 0)
+		s = options_get_string(w->options, "other-pane-width");
+		otherw = args_string_percentage(s, 0, sx, sx, &cause);
+		if (cause != NULL || otherw == 0) {
 			otherw = sx - mainw;
-		else if (otherw > sx || sx - otherw < mainw)
+			free(cause);
+		} else if (otherw > sx || sx - otherw < mainw)
 			otherw = sx - mainw;
 		else
 			mainw = sx - otherw;

options-table.c

@@ -647,19 +647,15 @@ const struct options_table_entry options_table[] = {
 	},
 
 	{ .name = "main-pane-height",
-	  .type = OPTIONS_TABLE_NUMBER,
+	  .type = OPTIONS_TABLE_STRING,
 	  .scope = OPTIONS_TABLE_WINDOW,
-	  .minimum = 1,
-	  .maximum = INT_MAX,
-	  .default_num = 24
+	  .default_str = "24"
 	},
 
 	{ .name = "main-pane-width",
-	  .type = OPTIONS_TABLE_NUMBER,
+	  .type = OPTIONS_TABLE_STRING,
 	  .scope = OPTIONS_TABLE_WINDOW,
-	  .minimum = 1,
-	  .maximum = INT_MAX,
-	  .default_num = 80
+	  .default_str = "80"
 	},
 
 	{ .name = "mode-keys",
@@ -696,19 +692,15 @@ const struct options_table_entry options_table[] = {
 	},
 
 	{ .name = "other-pane-height",
-	  .type = OPTIONS_TABLE_NUMBER,
+	  .type = OPTIONS_TABLE_STRING,
 	  .scope = OPTIONS_TABLE_WINDOW,
-	  .minimum = 0,
-	  .maximum = INT_MAX,
-	  .default_num = 0
+	  .default_str = "0"
 	},
 
 	{ .name = "other-pane-width",
-	  .type = OPTIONS_TABLE_NUMBER,
+	  .type = OPTIONS_TABLE_STRING,
 	  .scope = OPTIONS_TABLE_WINDOW,
-	  .minimum = 0,
-	  .maximum = INT_MAX,
-	  .default_num = 0
+	  .default_str = "0"
 	},
 
 	{ .name = "pane-active-border-style",

tmux.1

@@ -3711,6 +3711,9 @@ Set the width or height of the main (left or top) pane in the
 or
 .Ic main-vertical
 layouts.
+If suffixed by
+.Ql % ,
+this is a percentage of the window size.
 .Pp
 .It Xo Ic mode-keys
 .Op Ic vi | emacs
@@ -3764,6 +3767,9 @@ and
 .Ic other-pane-height
 options are set, the main pane will grow taller to make the other panes the
 specified height, but will never shrink to do so.
+If suffixed by
+.Ql % ,
+this is a percentage of the window size.
 .Pp
 .It Ic other-pane-width Ar width
 Like

tmux.h

@@ -2043,6 +2043,8 @@ long long	 args_strtonum(struct args *, u_char, long long, long long,
 		     char **);
 long long	 args_percentage(struct args *, u_char, long long,
 		     long long, long long, char **);
+long long	 args_string_percentage(const char *, long long, long long,
+		     long long, char **);
 
 /* cmd-find.c */
 int		 cmd_find_target(struct cmd_find_state *, struct cmdq_item *,