[atom] Move '*discriminated_atom*' functions from icccm to atom

3 files changed, 79 insertions, 0 deletions

diff --git a/atom/atoms.gperf.m4 b/atom/atoms.gperf.m4
index ec733de..b51122c 100644
--- a/atom/atoms.gperf.m4
+++ b/atom/atoms.gperf.m4
@@ -1,6 +1,15 @@
 %{
+
+/* Rely on vasprintf (GNU extension) instead of vsnprintf if
+   possible... */
+#ifdef HAVE_VASPRINTF
+#define _GNU_SOURCE
+#include <stdio.h>
+#endif
+
 #include <xcb/xcb.h>
 #include <stdlib.h>
+#include <stdarg.h>
 #include "xcb_atom.h"
 
 define(`COUNT', 0)dnl
@@ -113,3 +122,68 @@ int get_atom_name(xcb_connection_t *c, xcb_atom_t atom, const char **namep, int
 	free(atomr);
 	return 1;
 }
+
+static char *makename(const char *fmt, ...)
+{
+	char *ret;
+	int n;
+	va_list ap;
+
+#ifndef HAVE_VASPRINTF
+	char *np;
+	int size = 64;
+
+	/* First allocate 'size' bytes, should be enough usually */
+	if((ret = malloc(size)) == NULL)
+		return NULL;
+
+	while(1)
+	{
+		va_start(ap, fmt);
+		n = vsnprintf(ret, size, fmt, ap);
+		va_end(ap);
+
+		if(n < 0)
+			return NULL;
+
+		if(n < size)
+			return ret;
+
+		size = n + 1;
+		if((np = realloc(ret, size)) == NULL)
+		{
+			free(ret);
+			return NULL;
+		}
+
+		ret = np;
+	}
+#else
+	va_start(ap, fmt);
+	n = vasprintf(&ret, fmt, ap);
+	va_end(ap);
+
+	if(n < 0)
+		return NULL;
+
+	return ret;
+#endif
+}
+
+char *xcb_atom_name_by_screen(const char *base, uint8_t screen)
+{
+	return makename("%s_S%u", base, screen);
+}
+
+char *xcb_atom_name_by_resource(const char *base, uint32_t resource)
+{
+	return makename("%s_R%08X", base, resource);
+}
+
+char *xcb_atom_name_unique(const char *base, uint32_t id)
+{
+	if(base)
+		return makename("%s_U%lu", base, id);
+	else
+		return makename("U%lu", id);
+}
diff --git a/atom/xcb_atom.h.m4 b/atom/xcb_atom.h.m4
index 6ea81d3..48e874f 100644
--- a/atom/xcb_atom.h.m4
+++ b/atom/xcb_atom.h.m4
@@ -20,6 +20,10 @@ xcb_atom_t intern_atom_fast_reply(xcb_connection_t *c, intern_atom_fast_cookie_t
 const char *get_atom_name_predefined(xcb_atom_t atom);
 int get_atom_name(xcb_connection_t *c, xcb_atom_t atom, const char **namep, int *lengthp);
 
+char *xcb_atom_name_by_screen(const char *base, uint8_t screen);
+char *xcb_atom_name_by_resource(const char *base, uint32_t resource);
+char *xcb_atom_name_unique(const char *base, uint32_t id);
+
 define(`DO', `extern const xcb_atom_t $1;')dnl
 include(atomlist.m4)`'dnl
 
diff --git a/configure.ac b/configure.ac
index 73e6fbb..9188350 100644
--- a/configure.ac
+++ b/configure.ac
@@ -20,6 +20,7 @@ else
     fi
 fi
 AC_SUBST(CWARNFLAGS)
+AC_CHECK_FUNCS_ONCE(vasprintf)
 
 xcbincludedir='${includedir}/xcb'
 AC_SUBST(xcbincludedir)