randr: allow geometry strings to include @n

doc/fvwm3_manpage_source.adoc

@@ -341,6 +341,16 @@ the window's upper right hand corner 5 pixels above and to the left of
 the upper left hand corner of the screen; others may do just plain
 bizarre things.
 
+There is a fvwm-specific extension to geometry strings which can also
+enforce the geometry is relative to the given screen.  For example:
+
+....
+xterm -geometry +0+0@n
+....
+
+Where 'n' can be one of a RandR monitor name, or an assigned monitor number.
+For more details, see the RANDR SUPPORT section.
+
 There are several ways to cause a window to map onto a desktop or page
 other than the currently active one. The geometry technique mentioned
 above (specifying x,y coordinates larger than the physical screen size),

fvwm/expand.c

@@ -25,7 +25,6 @@
 #include "libs/ColorUtils.h"
 #include "libs/safemalloc.h"
 #include "libs/FEvent.h"
-#include "libs/strtonum.h"
 #include "fvwm.h"
 #include "externs.h"
 #include "cursor.h"
@@ -543,12 +542,10 @@ static signed int expand_vars_extended(
 
 		/* We could be left with "<NAME>.?" */
 		char		*m_name = NULL;
-		struct monitor  *mon2 = NULL, *m_loop;
+		struct monitor  *mon2 = NULL;
 		char		*rest_s;
-		const char	*errstr;
 		char *p_free;
 		int got_string;
-		int pos = -1;
 
 		/* The first word is the monitor name:
 		 *
@@ -560,22 +557,7 @@ static signed int expand_vars_extended(
 		p_free = rest_s;
 		got_string = 0;
 		while ((m_name = strsep(&rest_s, ".")) != NULL) {
-			/* Try parsing the name as a number.  If that fails,
-			 * then treat it as a valid name.
-			 */
-			pos = strtonum(m_name, 0, INT_MAX, &errstr);
-			if (errstr != NULL)
-				pos = -1;
-
-			RB_FOREACH(m_loop, monitors, &monitor_q) {
-				if (m_loop->number == pos) {
-					mon2 = m_loop;
-					goto rest;
-				}
-			}
-
 			mon2 = monitor_resolve_name(m_name);
-rest:
 			if (mon2 == NULL)
 			{
 				free(p_free);

libs/FScreen.c

@@ -29,6 +29,7 @@
 #include "FScreen.h"
 #include "FEvent.h"
 #include "queue.h"
+#include "strtonum.h"
 
 #define GLOBAL_SCREEN_NAME "_global"
 
@@ -114,6 +115,18 @@ monitor_scan_edges(struct monitor *m)
 	}
 }
 
+struct monitor *
+monitor_by_number(int n)
+{
+	struct monitor	*m_loop;
+
+	RB_FOREACH(m_loop, monitors, &monitor_q) {
+		if (m_loop->number == n)
+			return (m_loop);
+	}
+	return (NULL);
+}
+
 void
 monitor_refresh_global(void)
 {
@@ -217,11 +230,22 @@ struct monitor *
 monitor_resolve_name(const char *scr)
 {
 	struct monitor	*m = NULL;
+	int		 pos = -1;
+	const char	*errstr;
 
 	if (scr == NULL)
 	{
 		return NULL;
 	}
+
+	/* Try and look up the monitor as a number.  If that succeeds,
+	 * try and match that number as something valid in the monitor
+	 * information we have.
+	 */
+	pos = strtonum(scr, 0, INT_MAX, &errstr);
+	if (errstr == NULL)
+		return (monitor_by_number(pos));
+
 	/* "@g" is for the global screen. */
 	if (strcmp(scr, "g") == 0) {
 		m = monitor_get_global();

libs/FScreen.h

@@ -156,6 +156,7 @@ RB_PROTOTYPE(monitors, monitor, entry, monitor_compare);
 struct monitor	*monitor_resolve_name(const char *);
 struct monitor	*monitor_by_xy(int, int);
 struct monitor  *monitor_by_output(int);
+struct monitor	*monitor_by_number(int);
 struct monitor  *monitor_by_primary(void);
 struct monitor  *monitor_by_last_primary(void);
 struct monitor  *monitor_get_current(void);