config: support rc.yaml

Based on @johanmalm's work.

This adds libyaml as an optional dependency.

README.md

@@ -90,8 +90,8 @@ modification.
 
 Openbox spec is somewhat of a stable standard considering how long it has
 remained unchanged for and how wide-spread its adoption is by lightweight
-distributions such as LXDE, LXQt, BunsenLabs, ArchLabs, Mabox and Raspbian. Some
-widely used themes (for example Numix and Arc) have built-in support.
+distributions such as LXDE, LXQt, BunsenLabs, ArchLabs, Mabox and Raspbian.
+Some widely used themes (for example Numix and Arc) have built-in support.
 
 We could have invented a whole new syntax, but that's not where we want to
 spend our effort.
@@ -182,8 +182,8 @@ prevent installing the wlroots headers:
 ## 3. Configuration
 
 User config files are located at `${XDG_CONFIG_HOME:-$HOME/.config/labwc/}`
-with the following five files being used: [rc.xml], [menu.xml], [autostart], [shutdown],
-[environment] and [themerc-override].
+with the following five files being used: [rc.xml] (or [rc.yaml]), [menu.xml],
+[autostart], [shutdown], [environment] and [themerc-override].
 
 Run `labwc --reconfigure` to reload configuration and theme.
 
@@ -275,6 +275,7 @@ See [integration] for further details.
 [metacity]: https://github.com/GNOME/metacity
 
 [rc.xml]: docs/rc.xml.all
+[rc.yaml]: docs/rc.yaml
 [menu.xml]: docs/menu.xml
 [autostart]: docs/autostart
 [shutdown]: docs/shutdown

docs/README

@@ -3,6 +3,7 @@ Config layout for ~/.config/labwc/
 - environment
 - menu.xml
 - rc.xml
+- rc.yaml
 - shutdown
 - themerc-override
 - xinitrc

docs/labwc-config.5.scd

@@ -8,7 +8,8 @@ labwc - configuration files
 
 Labwc uses openbox-3.6 specification for configuration and theming, but does not
 support all options. The following files form the basis of the labwc
-configuration: rc.xml, menu.xml, autostart, shutdown, environment and xinitrc.
+configuration: rc.xml (or rc.yaml), menu.xml, autostart, shutdown, environment
+and xinitrc.
 
 No configuration files are needed to start and run labwc.
 
@@ -158,6 +159,77 @@ Note that in this manual, Boolean values are listed as [yes|no] for simplicity,
 but it's also possible to use [true|false] and\/or [on|off];
 this is for compatibility with Openbox.
 
+## YAML SUPPORT
+
+Labwc also supports YAML language for configuration. When rc.yaml exists
+instead of rc.xml, labwc internally converts it from YAML into XML and loads
+configurations from it. For example, "foo: bar" in YAML is converted to
+"<foo>bar</foo>" in XML. See /usr/share/docs/labwc/rc.yaml for an example
+configuration in YAML.
+
+If rc.yaml includes a key-value pair where the value is an array, it is
+converted to a sequence of <key>array-element</key> in XML.
+
+For example, a YAML expression:
+
+```
+touch:
+  - deviceName: xxxx
+    mapToOutput: eDP-1
+  - deviceName: yyyy
+    mapToOutput: HDMI-1
+```
+
+is converted to an XML expression:
+
+```
+<touch>
+  <deviceName>xxxx</deviceName>
+  <mapToOutput>eDP-1</mapToOutput>
+</touch>
+<touch>
+  <deviceName>yyyy</deviceName>
+  <mapToOutput>eDP-1</mapToOutput>
+</touch>
+```
+
+To avoid unnecessary indentations, some nodes that wrap array elements in XML
+can be ommitted. This includes:
+
+	- *<windowSwitcher><fields><field>*
+	- *<regions><region>*
+	- *<windowRules><windowRule>*
+	- *<libinput><device>*
+	- *<desktops><names><name>*
+
+For example, window switcher can be configured like:
+
+```
+windowSwitcher:
+  fields:
+    - content: type
+      width: 15%
+    - content: title
+      width: 85%
+```
+
+In addition, some specific keys in singular form with a sequence value in YAML
+are converted to plural form in XML. This includes:
+
+	- *keybinds* (converted to *keybind*)
+	- *mousebinds* (converted to *mousebind*)
+	- *actions* (converted to *action*)
+	- *fonts* (converted to *font*)
+	- *contexts* (converted to *context*)
+
+For example, keybinds can be configured like:
+
+```
+keybinds:
+  - { key: W-s, action: { name: Execute, command: foot } }
+  - { key: W-a, action: { name: Execute, command: fuzzel } }
+```
+
 ## CORE
 
 ```
@@ -573,9 +645,9 @@ extending outward from the snapped edge.
 	Load the default keybinds listed below. This is an addition to the
 	openbox specification and provides a way to keep config files simpler
 	whilst allowing your specific keybinds.
-	Note that if no rc.xml is found, or if no <keyboard><keybind> entries
-	exist, the same default keybinds will be loaded even if the <default />
-	element is not provided.
+	Note that if no rc.xml or rc.yaml is found, or if no <keyboard><keybind>
+	entries exist, the same default keybinds will be loaded even if the
+	<default /> element is not provided.
 
 ```
   A-Tab - next window
@@ -664,9 +736,10 @@ extending outward from the snapped edge.
 *<mouse><default />*
 	Load default mousebinds. This is an addition to the openbox
 	specification and provides a way to keep config files simpler whilst
-	allowing user specific binds.  Note that if no rc.xml is found, or if no
-	<mouse><mousebind> entries exist, the same default mousebinds will be
-	loaded even if the <default /> element is not provided.
+	allowing user specific binds.  Note that if no rc.xml or rc.yaml is
+	found, or if no <mouse><mousebind> entries exist, the same default
+	mousebinds will be loaded even if the <default /> element is not
+	provided.
 
 ## TOUCH
 

docs/meson.build

@@ -33,7 +33,8 @@ install_data(
     'shutdown',
     'themerc',
     'rc.xml',
-    'rc.xml.all'
+    'rc.xml.all',
+    'rc.yaml',
   ],
   install_dir: get_option('datadir') / 'doc' / meson.project_name()
 )

docs/rc.yaml

@@ -0,0 +1,89 @@
+# An example configuration file in YAML. To see all the configurations and
+# their descriptions, see docs/rc.xml.all or labwc-config(5).
+core:
+  xwaylandPersistence: yes
+placement:
+  policy: cascade
+theme:
+  dropShadows: yes
+  fonts:
+    - place: ActiveWindow
+      weight: bold
+    - place: InactiveWindow
+      weight: normal
+desktops:
+  number: 2
+windowSwitcher:
+  fields:
+    - content: type
+      width: 15%
+    - content: title
+      width: 85%
+resize:
+  drawContents: no
+focus:
+  followMouse: yes
+  followMouseRequiresMovement: yes
+  raiseOnFocus: no
+snapping:
+  range: 20
+  overlay:
+    delay:
+      inner: 100
+      outer: 0
+regions:
+  - { name: top-left,     x: 0%,  y: 0%,  width: 50%, height: 50% }
+  - { name: top-right,    x: 50%, y: 0%,  width: 50%, height: 50% }
+  - { name: bottom-left,  x: 0%,  y: 50%, width: 50%, height: 50% }
+  - { name: bottom-right, x: 50%, y: 50%, width: 50%, height: 50% }
+keyboard:
+  repeatRate: 25
+  repeatDelay: 600
+  keybinds:
+    - { key: W-bracketRight,        action: { name: ZoomIn } }
+    - { key: W-bracketLeft,         action: { name: ZoomOut } }
+    - { key: W-d,                   action: { name: Debug } }
+    - { key: W-1,                   action: { name: GoToDesktop, to: Workspace 1 } }
+    - { key: W-2,                   action: { name: GoToDesktop, to: Workspace 2 } }
+    - { key: W-m,                   action: { name: ToggleKeybinds } }
+    - { key: W-q,                   action: { name: Close } }
+    - { key: A-F4,                  action: { name: Close } }
+    - { key: A-Tab,                 action: { name: NextWindow } }
+    - { key: W-e,                   action: { name: Exit } }
+    - { key: W-v,                   action: { name: Execute, command: sh -c 'cliphist list | fuzzel --dmenu | cliphist decode | wl-copy' } }
+    - { key: W-Tab,                 action: { name: ToggleMaximize } }
+    - { key: W-s,                   action: { name: Execute, command: foot } }
+    - { key: W-a,                   action: { name: Execute, command: fuzzel } }
+    - { key: XF86_AudioLowerVolume, action: { name: Execute, command: pactl set-sink-volume @DEFAULT_SINK@ -2dB } }
+    - { key: XF86_AudioRaiseVolume, action: { name: Execute, command: pactl set-sink-volume @DEFAULT_SINK@ +2dB } }
+    - { key: XF86_AudioMute,        action: { name: Execute, command: pactl set-sink-mute @DEFAULT_SINK@ toggle } }
+    - { key: XF86_AudioMicMute,     action: { name: Execute, command: pactl set-source-mute @DEFAULT_SOURCE@ toggle } }
+    - { key: Print,                 action: { name: Execute, command: grim } }
+mouse:
+  doubleClickTime: 200
+  default:
+  contexts:
+    - name: Frame
+      mousebinds:
+        - { button: W-Left,  action: Press, actions: [ { name: Raise }, { name: Move } ] }
+        - { button: W-Right, action: Drag, action: { name: Raise } }
+        - { button: A-Left,  action: Press }
+        - { button: A-Left,  action: Drag }
+        - { button: A-Right, action: Press }
+        - { button: A-Right, action: Drag }
+touch:
+  deviceName: ELAN2514:00 04F3:2AF1
+  mapToOutput: eDP-1
+tablet:
+  mapToOutput: eDP-1
+libinput:
+  - category: non-touch
+    pointerSpeed: -0.4
+  - category: touchpad
+    naturalScroll: yes
+    tapAndDrag: no
+windowRules:
+  - identifier: ristretto
+    serverDecoration: no
+  - identifier: code-url-handler
+    action: { name: SetDecorations, decorations: border, forceSSD: yes }

include/common/yaml2xml.h

@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef LABWC_YAML2XML_H
+#define LABWC_YAML2XML_H
+#include <common/buf.h>
+#include <stdio.h>
+
+struct buf yaml_to_xml(FILE *stream, const char *toplevel_name);
+
+#endif /* LABWC_YAML2XML_H */

meson.build

@@ -72,6 +72,7 @@ pixman = dependency('pixman-1')
 math = cc.find_library('m')
 png = dependency('libpng')
 svg = dependency('librsvg-2.0', version: '>=2.46', required: false)
+yaml = dependency('yaml-0.1', required: false)
 
 if get_option('xwayland').enabled() and not wlroots_has_xwayland
 	error('no wlroots Xwayland support')
@@ -87,6 +88,13 @@ else
 endif
 conf_data.set10('HAVE_RSVG', have_rsvg)
 
+if get_option('yaml').disabled()
+  have_libyaml = false
+else
+  have_libyaml = yaml.found()
+endif
+conf_data.set10('HAVE_LIBYAML', have_libyaml)
+
 if get_option('static_analyzer').enabled()
   add_project_arguments(['-fanalyzer'], language: 'c')
 endif
@@ -125,6 +133,11 @@ if have_rsvg
     svg,
   ]
 endif
+if have_libyaml
+  labwc_deps += [
+    yaml,
+  ]
+endif
 
 subdir('include')
 subdir('src')

meson_options.txt

@@ -4,3 +4,4 @@ option('svg', type: 'feature', value: 'enabled', description: 'Enable svg window
 option('nls', type: 'feature', value: 'auto', description: 'Enable native language support')
 option('static_analyzer', type: 'feature', value: 'disabled', description: 'Run gcc static analyzer')
 option('test', type: 'feature', value: 'disabled', description: 'Run tests')
+option('yaml', type: 'feature', value: 'enabled', description: 'Enable configuration in YAML')

src/common/meson.build

@@ -19,3 +19,9 @@ labwc_sources += files(
   'spawn.c',
   'string-helpers.c',
 )
+
+if have_libyaml
+  labwc_sources += files(
+    'yaml2xml.c',
+  )
+endif

src/common/yaml2xml.c

@@ -0,0 +1,194 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <assert.h>
+#include <yaml.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+#include <strings.h>
+#include <wlr/util/log.h>
+#include "common/buf.h"
+#include "common/yaml2xml.h"
+
+struct lab_yaml_event {
+	yaml_event_type_t type;
+	char scalar[256];
+};
+
+static bool process_mapping(yaml_parser_t *parser, struct buf *buf);
+static bool process_sequence(yaml_parser_t *parser, struct buf *buf, char *key_name);
+
+static bool
+parse(yaml_parser_t *parser, struct lab_yaml_event *event)
+{
+	yaml_event_t yaml_event;
+	if (!yaml_parser_parse(parser, &yaml_event)) {
+		wlr_log(WLR_ERROR,
+			"Conversion from YAML to XML failed at %ld:%ld: %s",
+			parser->problem_mark.line + 1,
+			parser->problem_mark.column,
+			parser->problem);
+		return false;
+	}
+	event->type = yaml_event.type;
+	if (yaml_event.type == YAML_SCALAR_EVENT) {
+		snprintf(event->scalar, sizeof(event->scalar), "%s",
+			(char *)yaml_event.data.scalar.value);
+	}
+	yaml_event_delete(&yaml_event);
+	return event;
+}
+
+static bool
+process_value(yaml_parser_t *parser, struct buf *b,
+		struct lab_yaml_event *event, char *key_name)
+{
+	const char *parent_name = NULL;
+
+	switch (event->type) {
+	case YAML_MAPPING_START_EVENT:
+		buf_add_fmt(b, "<%s>", key_name);
+		if (!process_mapping(parser, b)) {
+			return false;
+		}
+		buf_add_fmt(b, "</%s>", key_name);
+		break;
+	case YAML_SEQUENCE_START_EVENT:
+		/*
+		 *     YAML                      XML
+		 * fields: [x,y] -> <fields><field>x<field><field>y<field<fields>
+		 */
+		if (!strcasecmp(key_name, "fields")) {
+			parent_name = "fields";
+			key_name = "field";
+		} else if (!strcasecmp(key_name, "regions")) {
+			parent_name = "regions";
+			key_name = "region";
+		} else if (!strcasecmp(key_name, "windowRules")) {
+			parent_name = "windowRules";
+			key_name = "windowRule";
+		} else if (!strcasecmp(key_name, "libinput")) {
+			parent_name = "libinput";
+			key_name = "device";
+		} else if (!strcasecmp(key_name, "names")) {
+			parent_name = "names";
+			key_name = "name";
+		} else if (!strcasecmp(key_name, "keybinds")) {
+			key_name = "keybind";
+		} else if (!strcasecmp(key_name, "mousebinds")) {
+			key_name = "mousebind";
+		} else if (!strcasecmp(key_name, "actions")) {
+			key_name = "action";
+		} else if (!strcasecmp(key_name, "fonts")) {
+			key_name = "font";
+		} else if (!strcasecmp(key_name, "contexts")) {
+			key_name = "context";
+		}
+		if (parent_name) {
+			buf_add_fmt(b, "<%s>", parent_name);
+		}
+		if (!process_sequence(parser, b, key_name)) {
+			return false;
+		}
+		if (parent_name) {
+			buf_add_fmt(b, "</%s>", parent_name);
+		}
+		break;
+	case YAML_SCALAR_EVENT:
+		/*
+		 * To avoid duplicated keys, mousebind: {event: Press} is
+		 * mapped to <mousebind action="Press">.
+		 */
+		if (!strcasecmp(key_name, "event")) {
+			key_name = "action";
+		}
+		buf_add_fmt(b, "<%s>%s</%s>", key_name, event->scalar, key_name);
+		break;
+	default:
+		break;
+	}
+	return true;
+}
+
+static bool
+process_sequence(yaml_parser_t *parser, struct buf *b, char *key_name)
+{
+	while (1) {
+		struct lab_yaml_event event;
+		if (!parse(parser, &event)) {
+			return false;
+		}
+		if (event.type == YAML_SEQUENCE_END_EVENT) {
+			return true;
+		}
+		if (!process_value(parser, b, &event, key_name)) {
+			return false;
+		}
+	}
+}
+
+static bool
+process_mapping(yaml_parser_t *parser, struct buf *buf)
+{
+	while (1) {
+		struct lab_yaml_event key_event, value_event;
+
+		if (!parse(parser, &key_event)) {
+			return false;
+		}
+		if (key_event.type == YAML_MAPPING_END_EVENT) {
+			return true;
+		}
+		if (key_event.type != YAML_SCALAR_EVENT) {
+			wlr_log(WLR_ERROR, "key must be scalar");
+			return false;
+		}
+		if (!parse(parser, &value_event)) {
+			return false;
+		}
+		if (!process_value(parser, buf, &value_event, key_event.scalar)) {
+			return false;
+		}
+		continue;
+	}
+}
+
+static bool
+process_root(yaml_parser_t *parser, struct buf *b, const char *toplevel_name)
+{
+	struct lab_yaml_event event;
+	if (!parse(parser, &event) || event.type != YAML_STREAM_START_EVENT) {
+		return false;
+	}
+	if (!parse(parser, &event) || event.type != YAML_DOCUMENT_START_EVENT) {
+		return false;
+	}
+	if (!parse(parser, &event) || event.type != YAML_MAPPING_START_EVENT) {
+		wlr_log(WLR_ERROR, "mapping is expected for toplevel node");
+		return false;
+	}
+
+	buf_add_fmt(b, "<%s>", toplevel_name);
+	if (!process_mapping(parser, b)) {
+		return false;
+	}
+	buf_add_fmt(b, "</%s>", toplevel_name);
+	return true;
+}
+
+struct buf
+yaml_to_xml(FILE *stream, const char *toplevel_name)
+{
+	struct buf b = BUF_INIT;
+	yaml_parser_t parser;
+	yaml_parser_initialize(&parser);
+	yaml_parser_set_input_file(&parser, stream);
+
+	bool success = process_root(&parser, &b, toplevel_name);
+	if (success) {
+		wlr_log(WLR_DEBUG, "XML converted from YAML: %s", b.data);
+	} else {
+		buf_reset(&b);
+	}
+	yaml_parser_delete(&parser);
+	return b;
+}

src/config/rcxml.c

@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0-only
 #define _POSIX_C_SOURCE 200809L
 #include <assert.h>
+#include <ctype.h>
 #include <fcntl.h>
 #include <glib.h>
 #include <libxml/parser.h>
@@ -15,6 +16,7 @@
 #include <wlr/util/box.h>
 #include <wlr/util/log.h>
 #include "action.h"
+#include "common/buf.h"
 #include "common/dir.h"
 #include "common/list.h"
 #include "common/macros.h"
@@ -36,6 +38,10 @@
 #include "window-rules.h"
 #include "workspaces.h"
 
+#if HAVE_LIBYAML
+#include "common/yaml2xml.h"
+#endif
+
 static bool in_regions;
 static bool in_usable_area_override;
 static bool in_keybind;
@@ -1743,6 +1749,37 @@ validate(void)
 	}
 }
 
+static bool
+file_is_xml(const char *filename)
+{
+	if (str_endswith(filename, ".xml")) {
+		return true;
+	} else if (str_endswith(filename, ".yaml")) {
+		return false;
+	}
+
+	/*
+	 * If the extension is not .xml or .yaml, judge by whther the content
+	 * starts with '<'.
+	 */
+	FILE *stream = fopen(filename, "r");
+	if (!stream) {
+		return true;
+	}
+	char c;
+	while ((c = fgetc(stream))) {
+		if (!isspace(c)) {
+			break;
+		}
+	}
+	fclose(stream);
+	if (c == '<') {
+		return true;
+	} else {
+		return false;
+	}
+}
+
 void
 rcxml_read(const char *filename)
 {
@@ -1758,9 +1795,14 @@ rcxml_read(const char *filename)
 		wl_list_append(&paths, &path->link);
 	} else {
 		paths_config_create(&paths, "rc.xml");
+#ifdef HAVE_LIBYAML
+		struct wl_list paths_yaml;
+		wl_list_init(&paths_yaml);
+		paths_config_create(&paths_yaml, "rc.yaml");
+		wl_list_insert_list(paths.prev, &paths_yaml);
+#endif
 	}
 
-	/* Reading file into buffer before parsing - better for unit tests */
 	bool should_merge_config = rc.merge_config;
 	struct wl_list *(*iter)(struct wl_list *list);
 	iter = should_merge_config ? paths_get_prev : paths_get_next;
@@ -1782,21 +1824,30 @@ rcxml_read(const char *filename)
 			continue;
 		}
 
-		wlr_log(WLR_INFO, "read config file %s", path->string);
-
 		struct buf b = BUF_INIT;
-		char *line = NULL;
-		size_t len = 0;
-		while (getline(&line, &len, stream) != -1) {
-			char *p = strrchr(line, '\n');
-			if (p) {
-				*p = '\0';
+		if (HAVE_LIBYAML && !file_is_xml(path->string)) {
+#if HAVE_LIBYAML
+			wlr_log(WLR_INFO, "read yaml config file %s", path->string);
+			b = yaml_to_xml(stream, "labwc_config");
+#endif
+		} else {
+			wlr_log(WLR_INFO, "read xml config file %s", path->string);
+			char *line = NULL;
+			size_t len = 0;
+			while (getline(&line, &len, stream) != -1) {
+				char *p = strrchr(line, '\n');
+				if (p) {
+					*p = '\0';
+				}
+				buf_add(&b, line);
 			}
-			buf_add(&b, line);
+			zfree(line);
 		}
-		zfree(line);
+
 		fclose(stream);
-		rcxml_parse_xml(&b);
+		if (b.len > 0) {
+			rcxml_parse_xml(&b);
+		}
 		buf_reset(&b);
 		if (!should_merge_config) {
 			break;

t/meson.build

@@ -1,18 +1,37 @@
-test_lib = static_library(
-  'test_lib',
-  sources: files(
+test_lib_sources = files(
     '../src/common/buf.c',
     '../src/common/mem.c',
-    '../src/common/string-helpers.c'
-  ),
-  include_directories: [labwc_inc],
-  dependencies: [dep_cmocka],
+    '../src/common/string-helpers.c',
 )
 
+test_deps = [
+  dep_cmocka,
+]
+
 tests = [
   'buf-simple',
 ]
 
+if have_libyaml
+  test_lib_sources += [
+    '../src/common/yaml2xml.c',
+  ]
+  test_deps += [
+    wlroots,
+    yaml,
+  ]
+  tests += [
+    'yaml2xml',
+  ]
+endif
+
+test_lib = static_library(
+  'test_lib',
+  sources: test_lib_sources,
+  include_directories: [labwc_inc],
+  dependencies: test_deps
+)
+
 foreach t : tests
   test(
     'test_@0@'.format(t),

t/yaml2xml.c

@@ -0,0 +1,99 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#define _POSIX_C_SOURCE 200809L
+#include <setjmp.h>
+#include <stdarg.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <string.h>
+#include <cmocka.h>
+#include "common/buf.h"
+#include "common/macros.h"
+#include "common/yaml2xml.h"
+
+struct test_set {
+	const char *name, *yaml, *xml;
+};
+
+const struct test_set test_sets[] = {
+	{
+		.name = "key-scalar",
+		.yaml = "xxx: yyy",
+		.xml = "<test><xxx>yyy</xxx></test>",
+	},
+	{
+		.name = "key-sequence",
+		.yaml = "xxx: [yyy, zzz]",
+		.xml = "<test><xxx>yyy</xxx><xxx>zzz</xxx></test>",
+	},
+	{
+		.name = "key-mapping",
+		.yaml = "xxx: {yyy: zzz}",
+		.xml = "<test><xxx><yyy>zzz</yyy></xxx></test>",
+	},
+	{
+		.name = "window-switcher-fields",
+		.yaml = "windowSwitcher: {fields: [xxx, yyy]}",
+		.xml =
+			"<test><windowSwitcher><fields>"
+				"<field>xxx</field>"
+				"<field>yyy</field>"
+			"</fields></windowSwitcher></test>",
+	},
+	{
+		.name = "theme-fonts",
+		.yaml = "theme: {fonts: [xxx, yyy]}",
+		.xml =
+			"<test><theme>"
+				"<font>xxx</font>"
+				"<font>yyy</font>"
+			"</theme></test>",
+	},
+	{
+		.name = "mousebinds",
+		.yaml =
+			"mousebinds:\n"
+        		"  - { button: W-Left,  action: Press, actions: [ { name: Raise }, { name: Move } ] }\n"
+			"  - { button: W-Right, action: Drag,  action: { name: Resize} }\n",
+		.xml =
+			"<test>"
+			"<mousebind>"
+				"<button>W-Left</button>"
+				"<action>Press</action>"
+				"<action><name>Raise</name></action>"
+				"<action><name>Move</name></action>"
+			"</mousebind>"
+			"<mousebind>"
+				"<button>W-Right</button>"
+				"<action>Drag</action>"
+				"<action><name>Resize</name></action>"
+			"</mousebind>"
+			"</test>",
+	},
+};
+
+static void
+test_yaml_to_xml(void **state)
+{
+	(void)state;
+	for (int i = 0; i < (int)ARRAY_SIZE(test_sets); i++) {
+		const struct test_set *set = &test_sets[i];
+
+		char buf[1024];
+		FILE *stream = fmemopen(buf, sizeof(buf), "w+");
+		fwrite(set->yaml, strlen(set->yaml), 1, stream);
+		fseek(stream, 0, SEEK_SET);
+
+		struct buf b = yaml_to_xml(stream, "test");
+		fclose(stream);
+		assert_string_equal(b.data, set->xml);
+	}
+}
+
+int main(int argc, char **argv)
+{
+	const struct CMUnitTest tests[] = {
+		cmocka_unit_test(test_yaml_to_xml),
+	};
+
+	return cmocka_run_group_tests(tests, NULL, NULL);
+}