Introduce libwayland-cursor, a cursor helper library

The purpose of this library is to be the equivalent of libXcursor in
the X world. This library is compatible with X cursor themes and loads
them directly into an shm pool making it easy for the clients to get
buffer for each cursor image.

The code for handling the X cursor theme was taken from libXcursor. The
files cursor/xcursor.[ch] are a stripped down version of that library
containing only the interfaces necessary for implementing the wayland
counterpart.

6 files changed, 1372 insertions, 0 deletions

diff --git a/cursor/Makefile.am b/cursor/Makefile.am
new file mode 100644
index 0000000..edfa3e3
--- /dev/null
+++ b/cursor/Makefile.am
@@ -0,0 +1,14 @@
+lib_LTLIBRARIES = libwayland-cursor.la
+
+include_HEADERS = wayland-cursor.h
+
+libwayland_cursor_la_SOURCES =			\
+	wayland-cursor.c			\
+	xcursor.c				\
+	xcursor.h
+
+pkgconfigdir = $(libdir)/pkgconfig
+pkgconfig_DATA = wayland-cursor.pc
+
+AM_CFLAGS = $(GCC_CFLAGS) -I../src
+LDADD = $(top_builddir)/src/libwayland-client.la
diff --git a/cursor/wayland-cursor.c b/cursor/wayland-cursor.c
new file mode 100644
index 0000000..cad725f
--- /dev/null
+++ b/cursor/wayland-cursor.c
@@ -0,0 +1,356 @@
+/*
+ * Copyright © 2012 Intel Corporation
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that copyright
+ * notice and this permission notice appear in supporting documentation, and
+ * that the name of the copyright holders not be used in advertising or
+ * publicity pertaining to distribution of the software without specific,
+ * written prior permission.  The copyright holders make no representations
+ * about the suitability of this software for any purpose.  It is provided "as
+ * is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ * OF THIS SOFTWARE.
+ */
+
+#include "xcursor.h"
+#include "wayland-cursor.h"
+#include "wayland-client.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/mman.h>
+
+struct shm_pool {
+	struct wl_shm_pool *pool;
+	int fd;
+	unsigned int size;
+	unsigned int used;
+	char *data;
+};
+
+static struct shm_pool *
+shm_pool_create(struct wl_shm *shm, int size)
+{
+	struct shm_pool *pool;
+	char filename[] = "/tmp/wayland-shm-XXXXXX";
+
+	pool = malloc(sizeof *pool);
+	if (!pool)
+		return NULL;
+
+	pool->fd = mkstemp(filename);
+	if (pool->fd < 0)
+		return NULL;
+
+	if (ftruncate(pool->fd, size) < 0) {
+		close(pool->fd);
+		return NULL;
+	}
+
+	pool->data = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED,
+			  pool->fd, 0);
+	unlink(filename);
+
+	if (pool->data == MAP_FAILED) {
+		close(pool->fd);
+		return NULL;
+	}
+
+	pool->pool = wl_shm_create_pool(shm, pool->fd, size);
+	pool->size = size;
+	pool->used = 0;
+
+	return pool;
+}
+
+static int
+shm_pool_resize(struct shm_pool *pool, int size)
+{
+	if (ftruncate(pool->fd, size) < 0)
+		return 0;
+
+	wl_shm_pool_resize(pool->pool, size);
+
+	munmap(pool->data, pool->size);
+
+	pool->data = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED,
+			  pool->fd, 0);
+	pool->size = size;
+
+	return 1;
+}
+
+static int
+shm_pool_allocate(struct shm_pool *pool, int size)
+{
+	int offset;
+
+	if (pool->used + size > pool->size)
+		if (!shm_pool_resize(pool, 2 * pool->size + size))
+			return -1;
+
+	offset = pool->used;
+	pool->used += size;
+
+	return offset;
+}
+
+static void
+shm_pool_destroy(struct shm_pool *pool)
+{
+	munmap(pool->data, pool->size);
+	wl_shm_pool_destroy(pool->pool);
+	free(pool);
+}
+
+
+static const char *cursor_names[] = {
+	"bottom_left_corner",
+	"bottom_right_corner",
+	"bottom_side",
+	"grabbing",
+	"left_ptr",
+	"left_side",
+	"right_side",
+	"top_left_corner",
+	"top_right_corner",
+	"top_side",
+	"xterm",
+	"hand1",
+};
+
+struct wl_cursor_theme {
+	unsigned int cursor_count;
+	struct wl_cursor **cursors;
+	struct wl_shm *shm;
+	struct shm_pool *pool;
+	char *name;
+	int size;
+};
+
+struct cursor_image {
+	struct wl_cursor_image image;
+	struct wl_cursor_theme *theme;
+	struct wl_buffer *buffer;
+	int offset; /* data offset of this image in the shm pool */
+};
+
+/** Get an shm buffer for a cursor image
+ *
+ * \param image The cursor image
+ * \return An shm buffer for the cursor image. The user should not destroy
+ * the returned buffer.
+ */
+WL_EXPORT struct wl_buffer *
+wl_cursor_image_get_buffer(struct wl_cursor_image *_img)
+{
+	struct cursor_image *image = (struct cursor_image *) _img;
+	struct wl_cursor_theme *theme = image->theme;
+
+	if (!image->buffer) {
+		image->buffer =
+			wl_shm_pool_create_buffer(theme->pool->pool,
+						  image->offset,
+						  _img->width, _img->height,
+						  _img->width * 4,
+						  WL_SHM_FORMAT_ARGB8888);
+	};
+
+	return image->buffer;
+}
+
+static void
+wl_cursor_image_destroy(struct wl_cursor_image *_img)
+{
+	struct cursor_image *image = (struct cursor_image *) _img;
+
+	if (image->buffer)
+		wl_buffer_destroy(image->buffer);
+
+	free(image);
+}
+
+static void
+wl_cursor_destroy(struct wl_cursor *cursor)
+{
+	unsigned int i;
+
+	for (i = 0; i < cursor->image_count; i++)
+		wl_cursor_image_destroy(cursor->images[i]);
+
+	free(cursor->name);
+	free(cursor);
+}
+
+static struct wl_cursor *
+load_cursor(struct wl_cursor_theme *theme, const char *name)
+{
+	XcursorImages *images;
+	struct wl_cursor *cursor;
+	struct cursor_image *image;
+	int i, size;
+
+	images = XcursorLibraryLoadImages(name, theme->name, theme->size);
+	if (!images)
+		return NULL;
+
+	cursor = malloc(sizeof *cursor);
+	if (!cursor) {
+		XcursorImagesDestroy(images);
+		return NULL;
+	}
+
+	cursor->image_count = images->nimage;
+	cursor->images = malloc(images->nimage * sizeof cursor->images[0]);
+	if (!cursor->images) {
+		XcursorImagesDestroy(images);
+		free(cursor);
+		return NULL;
+	}
+
+	cursor->name = strdup(name);
+
+	for (i = 0; i < images->nimage; i++) {
+		image = malloc(sizeof *image);
+		cursor->images[i] = (struct wl_cursor_image *) image;
+
+		image->theme = theme;
+		image->buffer = NULL;
+
+		image->image.width = images->images[i]->width;
+		image->image.height = images->images[i]->height;
+		image->image.hotspot_x = images->images[i]->xhot;
+		image->image.hotspot_y = images->images[i]->yhot;
+		image->image.delay = images->images[i]->delay;
+
+		/* copy pixels to shm pool */
+		size = image->image.width * image->image.height * 4;
+		image->offset = shm_pool_allocate(theme->pool, size);
+		memcpy(theme->pool->data + image->offset,
+		       images->images[i]->pixels, size);
+	}
+
+	XcursorImagesDestroy(images);
+
+	return cursor;
+}
+
+/** Load a cursor theme to memory shared with the compositor
+ *
+ * \param name The name of the cursor theme to load. If %NULL, the default
+ * theme will be loaded.
+ * \param size Desired size of the cursor images.
+ * \param shm The compositor's shm interface.
+ *
+ * \return An object representing the theme that should be destroyed with
+ * wl_cursor_theme_destroy() or %NULL on error.
+ */
+WL_EXPORT struct wl_cursor_theme *
+wl_cursor_theme_load(const char *name, int size, struct wl_shm *shm)
+{
+	struct wl_cursor_theme *theme;
+	unsigned int i;
+
+	theme = malloc(sizeof *theme);
+	if (!theme)
+		return NULL;
+
+	if (!name)
+		name = "default";
+
+	theme->name = strdup(name);
+	theme->size = size;
+	theme->cursor_count = ARRAY_LENGTH(cursor_names);
+
+	theme->cursors =
+		malloc(theme->cursor_count * sizeof theme->cursors[0]);
+	if (!theme->cursors) {
+		free(theme);
+		return NULL;
+	}
+
+	theme->pool =
+		shm_pool_create(shm, theme->cursor_count * size * size * 4);
+
+	for (i = 0; i < theme->cursor_count; i++)
+		theme->cursors[i] = load_cursor(theme, cursor_names[i]);
+
+	return theme;
+}
+
+/** Destroys a cursor theme object
+ *
+ * \param theme The cursor theme to be destroyed
+ */
+WL_EXPORT void
+wl_cursor_theme_destroy(struct wl_cursor_theme *theme)
+{
+	unsigned int i;
+
+	for (i = 0; i < theme->cursor_count; i++)
+		wl_cursor_destroy(theme->cursors[i]);
+
+	shm_pool_destroy(theme->pool);
+
+	free(theme->cursors);
+	free(theme);
+}
+
+/** Get the cursor for a given type from a cursor theme
+ *
+ * \param theme The cursor theme
+ * \patam type The desired cursor type
+ * \return The theme's cursor of the given type or %NULL if there is no
+ * such cursor
+ */
+WL_EXPORT struct wl_cursor *
+wl_cursor_theme_get_cursor(struct wl_cursor_theme *theme,
+			   enum wl_cursor_type type)
+{
+	if (type < theme->cursor_count)
+		return theme->cursors[type];
+
+	return NULL;
+}
+
+/** Get the cursor for a given name from a cursor theme
+ *
+ * \param theme The cursor theme
+ * \param name Name of the desired cursor
+ * \return The theme's cursor of the given name or %NULL if there is no
+ * such cursor
+ */
+WL_EXPORT struct wl_cursor *
+wl_cursor_theme_get_cursor_by_name(struct wl_cursor_theme *theme,
+				   const char *name)
+{
+	unsigned int i;
+	struct wl_cursor *cursor;
+
+	for (i = 0; i < theme->cursor_count; i++) {
+		if (strcmp(name, theme->cursors[i]->name) == 0)
+			return theme->cursors[i];
+	}
+
+	cursor = load_cursor(theme, name);
+	if (!cursor)
+		return NULL;
+
+	theme->cursor_count++;
+	theme->cursors =
+		realloc(theme->cursors,
+			theme->cursor_count * sizeof theme->cursors[0]);
+
+	theme->cursors[theme->cursor_count - 1] = cursor;
+
+	return cursor;
+}
diff --git a/cursor/wayland-cursor.h b/cursor/wayland-cursor.h
new file mode 100644
index 0000000..154cd84
--- /dev/null
+++ b/cursor/wayland-cursor.h
@@ -0,0 +1,78 @@
+/*
+ * Copyright © 2012 Intel Corporation
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that copyright
+ * notice and this permission notice appear in supporting documentation, and
+ * that the name of the copyright holders not be used in advertising or
+ * publicity pertaining to distribution of the software without specific,
+ * written prior permission.  The copyright holders make no representations
+ * about the suitability of this software for any purpose.  It is provided "as
+ * is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ * OF THIS SOFTWARE.
+ */
+
+#ifndef WAYLAND_CURSOR_H
+#define WAYLAND_CURSOR_H
+
+#include <stdint.h>
+
+enum wl_cursor_type {
+	WL_CURSOR_BOTTOM_LEFT,
+	WL_CURSOR_BOTTOM_RIGHT,
+	WL_CURSOR_BOTTOM,
+	WL_CURSOR_DRAGGING,
+	WL_CURSOR_LEFT_PTR,
+	WL_CURSOR_LEFT,
+	WL_CURSOR_RIGHT,
+	WL_CURSOR_TOP_LEFT,
+	WL_CURSOR_TOP_RIGHT,
+	WL_CURSOR_TOP,
+	WL_CURSOR_IBEAM,
+	WL_CURSOR_HAND1,
+};
+
+struct wl_cursor_theme;
+
+struct wl_cursor_image {
+	uint32_t width;		/* actual width */
+	uint32_t height;	/* actual height */
+	uint32_t hotspot_x;	/* hot spot x (must be inside image) */
+	uint32_t hotspot_y;	/* hot spot y (must be inside image) */
+	uint32_t delay;		/* animation delay to next frame (ms) */
+};
+
+struct wl_cursor {
+	unsigned int image_count;
+	struct wl_cursor_image **images;
+	char *name;
+};
+
+struct wl_shm;
+
+struct wl_cursor_theme *
+wl_cursor_theme_load(const char *name, int size, struct wl_shm *shm);
+
+void
+wl_cursor_theme_destroy(struct wl_cursor_theme *theme);
+
+struct wl_cursor *
+wl_cursor_theme_get_cursor(struct wl_cursor_theme *theme,
+			   enum wl_cursor_type type);
+
+struct wl_cursor *
+wl_cursor_theme_get_cursor_by_name(struct wl_cursor_theme *theme,
+				   const char *name);
+
+struct wl_buffer *
+wl_cursor_image_get_buffer(struct wl_cursor_image *image);
+
+#endif
diff --git a/cursor/wayland-cursor.pc.in b/cursor/wayland-cursor.pc.in
new file mode 100644
index 0000000..b10d039
--- /dev/null
+++ b/cursor/wayland-cursor.pc.in
@@ -0,0 +1,10 @@
+prefix=@prefix@
+exec_prefix=${prefix}
+libdir=${exec_prefix}/lib
+includedir=${prefix}/include
+ 
+Name: Wayland Cursor
+Description: Wayland cursor helper library
+Version: @WAYLAND_VERSION@
+Cflags: -I${includedir}
+Libs: -L${libdir} -lwayland-cursor
diff --git a/cursor/xcursor.c b/cursor/xcursor.c
new file mode 100644
index 0000000..9bec8c7
--- /dev/null
+++ b/cursor/xcursor.c
@@ -0,0 +1,856 @@
+/*
+ * Copyright © 2002 Keith Packard
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that
+ * copyright notice and this permission notice appear in supporting
+ * documentation, and that the name of Keith Packard not be used in
+ * advertising or publicity pertaining to distribution of the software without
+ * specific, written prior permission.  Keith Packard makes no
+ * representations about the suitability of this software for any purpose.  It
+ * is provided "as is" without express or implied warranty.
+ *
+ * KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "xcursor.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+/*
+ * From libXcursor/include/X11/extensions/Xcursor.h
+ */
+
+#define XcursorTrue	1
+#define XcursorFalse	0
+
+/*
+ * Cursor files start with a header.  The header
+ * contains a magic number, a version number and a
+ * table of contents which has type and offset information
+ * for the remaining tables in the file.
+ *
+ * File minor versions increment for compatible changes
+ * File major versions increment for incompatible changes (never, we hope)
+ *
+ * Chunks of the same type are always upward compatible.  Incompatible
+ * changes are made with new chunk types; the old data can remain under
+ * the old type.  Upward compatible changes can add header data as the
+ * header lengths are specified in the file.
+ *
+ *  File:
+ *	FileHeader
+ *	LISTofChunk
+ *
+ *  FileHeader:
+ *	CARD32		magic	    magic number
+ *	CARD32		header	    bytes in file header
+ *	CARD32		version	    file version
+ *	CARD32		ntoc	    number of toc entries
+ *	LISTofFileToc   toc	    table of contents
+ *
+ *  FileToc:
+ *	CARD32		type	    entry type
+ *	CARD32		subtype	    entry subtype (size for images)
+ *	CARD32		position    absolute file position
+ */
+
+#define XCURSOR_MAGIC	0x72756358  /* "Xcur" LSBFirst */
+
+/*
+ * Current Xcursor version number.  Will be substituted by configure
+ * from the version in the libXcursor configure.ac file.
+ */
+
+#define XCURSOR_LIB_MAJOR 1
+#define XCURSOR_LIB_MINOR 1
+#define XCURSOR_LIB_REVISION 13
+#define XCURSOR_LIB_VERSION	((XCURSOR_LIB_MAJOR * 10000) + \
+				 (XCURSOR_LIB_MINOR * 100) + \
+				 (XCURSOR_LIB_REVISION))
+
+/*
+ * This version number is stored in cursor files; changes to the
+ * file format require updating this version number
+ */
+#define XCURSOR_FILE_MAJOR	1
+#define XCURSOR_FILE_MINOR	0
+#define XCURSOR_FILE_VERSION	((XCURSOR_FILE_MAJOR << 16) | (XCURSOR_FILE_MINOR))
+#define XCURSOR_FILE_HEADER_LEN	(4 * 4)
+#define XCURSOR_FILE_TOC_LEN	(3 * 4)
+
+typedef struct _XcursorFileToc {
+    XcursorUInt	    type;	/* chunk type */
+    XcursorUInt	    subtype;	/* subtype (size for images) */
+    XcursorUInt	    position;	/* absolute position in file */
+} XcursorFileToc;
+
+typedef struct _XcursorFileHeader {
+    XcursorUInt	    magic;	/* magic number */
+    XcursorUInt	    header;	/* byte length of header */
+    XcursorUInt	    version;	/* file version number */
+    XcursorUInt	    ntoc;	/* number of toc entries */
+    XcursorFileToc  *tocs;	/* table of contents */
+} XcursorFileHeader;
+
+/*
+ * The rest of the file is a list of chunks, each tagged by type
+ * and version.
+ *
+ *  Chunk:
+ *	ChunkHeader
+ *	<extra type-specific header fields>
+ *	<type-specific data>
+ *
+ *  ChunkHeader:
+ *	CARD32	    header	bytes in chunk header + type header
+ *	CARD32	    type	chunk type
+ *	CARD32	    subtype	chunk subtype
+ *	CARD32	    version	chunk type version
+ */
+
+#define XCURSOR_CHUNK_HEADER_LEN    (4 * 4)
+
+typedef struct _XcursorChunkHeader {
+    XcursorUInt	    header;	/* bytes in chunk header */
+    XcursorUInt	    type;	/* chunk type */
+    XcursorUInt	    subtype;	/* chunk subtype (size for images) */
+    XcursorUInt	    version;	/* version of this type */
+} XcursorChunkHeader;
+
+/*
+ * Here's a list of the known chunk types
+ */
+
+/*
+ * Comments consist of a 4-byte length field followed by
+ * UTF-8 encoded text
+ *
+ *  Comment:
+ *	ChunkHeader header	chunk header
+ *	CARD32	    length	bytes in text
+ *	LISTofCARD8 text	UTF-8 encoded text
+ */
+
+#define XCURSOR_COMMENT_TYPE	    0xfffe0001
+#define XCURSOR_COMMENT_VERSION	    1
+#define XCURSOR_COMMENT_HEADER_LEN  (XCURSOR_CHUNK_HEADER_LEN + (1 *4))
+#define XCURSOR_COMMENT_COPYRIGHT   1
+#define XCURSOR_COMMENT_LICENSE	    2
+#define XCURSOR_COMMENT_OTHER	    3
+#define XCURSOR_COMMENT_MAX_LEN	    0x100000
+
+typedef struct _XcursorComment {
+    XcursorUInt	    version;
+    XcursorUInt	    comment_type;
+    char	    *comment;
+} XcursorComment;
+
+/*
+ * Each cursor image occupies a separate image chunk.
+ * The length of the image header follows the chunk header
+ * so that future versions can extend the header without
+ * breaking older applications
+ *
+ *  Image:
+ *	ChunkHeader	header	chunk header
+ *	CARD32		width	actual width
+ *	CARD32		height	actual height
+ *	CARD32		xhot	hot spot x
+ *	CARD32		yhot	hot spot y
+ *	CARD32		delay	animation delay
+ *	LISTofCARD32	pixels	ARGB pixels
+ */
+
+#define XCURSOR_IMAGE_TYPE    	    0xfffd0002
+#define XCURSOR_IMAGE_VERSION	    1
+#define XCURSOR_IMAGE_HEADER_LEN    (XCURSOR_CHUNK_HEADER_LEN + (5*4))
+#define XCURSOR_IMAGE_MAX_SIZE	    0x7fff	/* 32767x32767 max cursor size */
+
+typedef struct _XcursorFile XcursorFile;
+
+struct _XcursorFile {
+    void    *closure;
+    int	    (*read)  (XcursorFile *file, unsigned char *buf, int len);
+    int	    (*write) (XcursorFile *file, unsigned char *buf, int len);
+    int	    (*seek)  (XcursorFile *file, long offset, int whence);
+};
+
+typedef struct _XcursorComments {
+    int		    ncomment;	/* number of comments */
+    XcursorComment  **comments;	/* array of XcursorComment pointers */
+} XcursorComments;
+
+/*
+ * From libXcursor/src/file.c
+ */
+
+static XcursorImage *
+XcursorImageCreate (int width, int height)
+{
+    XcursorImage    *image;
+
+    image = malloc (sizeof (XcursorImage) +
+		    width * height * sizeof (XcursorPixel));
+    if (!image)
+	return NULL;
+    image->version = XCURSOR_IMAGE_VERSION;
+    image->pixels = (XcursorPixel *) (image + 1);
+    image->size = width > height ? width : height;
+    image->width = width;
+    image->height = height;
+    image->delay = 0;
+    return image;
+}
+
+static void
+XcursorImageDestroy (XcursorImage *image)
+{
+    free (image);
+}
+
+static XcursorImages *
+XcursorImagesCreate (int size)
+{
+    XcursorImages   *images;
+
+    images = malloc (sizeof (XcursorImages) +
+		     size * sizeof (XcursorImage *));
+    if (!images)
+	return NULL;
+    images->nimage = 0;
+    images->images = (XcursorImage **) (images + 1);
+    images->name = NULL;
+    return images;
+}
+
+void
+XcursorImagesDestroy (XcursorImages *images)
+{
+    int	n;
+
+    if (!images)
+        return;
+
+    for (n = 0; n < images->nimage; n++)
+	XcursorImageDestroy (images->images[n]);
+    if (images->name)
+	free (images->name);
+    free (images);
+}
+
+static void
+XcursorImagesSetName (XcursorImages *images, const char *name)
+{
+    char    *new;
+
+    if (!images || !name)
+        return;
+
+    new = malloc (strlen (name) + 1);
+
+    if (!new)
+	return;
+
+    strcpy (new, name);
+    if (images->name)
+	free (images->name);
+    images->name = new;
+}
+
+static XcursorBool
+_XcursorReadUInt (XcursorFile *file, XcursorUInt *u)
+{
+    unsigned char   bytes[4];
+
+    if (!file || !u)
+        return XcursorFalse;
+
+    if ((*file->read) (file, bytes, 4) != 4)
+	return XcursorFalse;
+    *u = ((bytes[0] << 0) |
+	  (bytes[1] << 8) |
+	  (bytes[2] << 16) |
+	  (bytes[3] << 24));
+    return XcursorTrue;
+}
+
+static void
+_XcursorFileHeaderDestroy (XcursorFileHeader *fileHeader)
+{
+    free (fileHeader);
+}
+
+static XcursorFileHeader *
+_XcursorFileHeaderCreate (int ntoc)
+{
+    XcursorFileHeader	*fileHeader;
+
+    if (ntoc > 0x10000)
+	return NULL;
+    fileHeader = malloc (sizeof (XcursorFileHeader) +
+			 ntoc * sizeof (XcursorFileToc));
+    if (!fileHeader)
+	return NULL;
+    fileHeader->magic = XCURSOR_MAGIC;
+    fileHeader->header = XCURSOR_FILE_HEADER_LEN;
+    fileHeader->version = XCURSOR_FILE_VERSION;
+    fileHeader->ntoc = ntoc;
+    fileHeader->tocs = (XcursorFileToc *) (fileHeader + 1);
+    return fileHeader;
+}
+
+static XcursorFileHeader *
+_XcursorReadFileHeader (XcursorFile *file)
+{
+    XcursorFileHeader	head, *fileHeader;
+    XcursorUInt		skip;
+    int			n;
+
+    if (!file)
+        return NULL;
+
+    if (!_XcursorReadUInt (file, &head.magic))
+	return NULL;
+    if (head.magic != XCURSOR_MAGIC)
+	return NULL;
+    if (!_XcursorReadUInt (file, &head.header))
+	return NULL;
+    if (!_XcursorReadUInt (file, &head.version))
+	return NULL;
+    if (!_XcursorReadUInt (file, &head.ntoc))
+	return NULL;
+    skip = head.header - XCURSOR_FILE_HEADER_LEN;
+    if (skip)
+	if ((*file->seek) (file, skip, SEEK_CUR) == EOF)
+	    return NULL;
+    fileHeader = _XcursorFileHeaderCreate (head.ntoc);
+    if (!fileHeader)
+	return NULL;
+    fileHeader->magic = head.magic;
+    fileHeader->header = head.header;
+    fileHeader->version = head.version;
+    fileHeader->ntoc = head.ntoc;
+    for (n = 0; n < fileHeader->ntoc; n++)
+    {
+	if (!_XcursorReadUInt (file, &fileHeader->tocs[n].type))
+	    break;
+	if (!_XcursorReadUInt (file, &fileHeader->tocs[n].subtype))
+	    break;
+	if (!_XcursorReadUInt (file, &fileHeader->tocs[n].position))
+	    break;
+    }
+    if (n != fileHeader->ntoc)
+    {
+	_XcursorFileHeaderDestroy (fileHeader);
+	return NULL;
+    }
+    return fileHeader;
+}
+
+static XcursorBool
+_XcursorSeekToToc (XcursorFile		*file,
+		   XcursorFileHeader	*fileHeader,
+		   int			toc)
+{
+    if (!file || !fileHeader || \
+        (*file->seek) (file, fileHeader->tocs[toc].position, SEEK_SET) == EOF)
+	return XcursorFalse;
+    return XcursorTrue;
+}
+
+static XcursorBool
+_XcursorFileReadChunkHeader (XcursorFile	*file,
+			     XcursorFileHeader	*fileHeader,
+			     int		toc,
+			     XcursorChunkHeader	*chunkHeader)
+{
+    if (!file || !fileHeader || !chunkHeader)
+        return XcursorFalse;
+    if (!_XcursorSeekToToc (file, fileHeader, toc))
+	return XcursorFalse;
+    if (!_XcursorReadUInt (file, &chunkHeader->header))
+	return XcursorFalse;
+    if (!_XcursorReadUInt (file, &chunkHeader->type))
+	return XcursorFalse;
+    if (!_XcursorReadUInt (file, &chunkHeader->subtype))
+	return XcursorFalse;
+    if (!_XcursorReadUInt (file, &chunkHeader->version))
+	return XcursorFalse;
+    /* sanity check */
+    if (chunkHeader->type != fileHeader->tocs[toc].type ||
+	chunkHeader->subtype != fileHeader->tocs[toc].subtype)
+	return XcursorFalse;
+    return XcursorTrue;
+}
+
+#define dist(a,b)   ((a) > (b) ? (a) - (b) : (b) - (a))
+
+static XcursorDim
+_XcursorFindBestSize (XcursorFileHeader *fileHeader,
+		      XcursorDim	size,
+		      int		*nsizesp)
+{
+    int		n;
+    int		nsizes = 0;
+    XcursorDim	bestSize = 0;
+    XcursorDim	thisSize;
+
+    if (!fileHeader || !nsizesp)
+        return 0;
+
+    for (n = 0; n < fileHeader->ntoc; n++)
+    {
+	if (fileHeader->tocs[n].type != XCURSOR_IMAGE_TYPE)
+	    continue;
+	thisSize = fileHeader->tocs[n].subtype;
+	if (!bestSize || dist (thisSize, size) < dist (bestSize, size))
+	{
+	    bestSize = thisSize;
+	    nsizes = 1;
+	}
+	else if (thisSize == bestSize)
+	    nsizes++;
+    }
+    *nsizesp = nsizes;
+    return bestSize;
+}
+
+static int
+_XcursorFindImageToc (XcursorFileHeader	*fileHeader,
+		      XcursorDim	size,
+		      int		count)
+{
+    int			toc;
+    XcursorDim		thisSize;
+
+    if (!fileHeader)
+        return 0;
+
+    for (toc = 0; toc < fileHeader->ntoc; toc++)
+    {
+	if (fileHeader->tocs[toc].type != XCURSOR_IMAGE_TYPE)
+	    continue;
+	thisSize = fileHeader->tocs[toc].subtype;
+	if (thisSize != size)
+	    continue;
+	if (!count)
+	    break;
+	count--;
+    }
+    if (toc == fileHeader->ntoc)
+	return -1;
+    return toc;
+}
+
+static XcursorImage *
+_XcursorReadImage (XcursorFile		*file,
+		   XcursorFileHeader	*fileHeader,
+		   int			toc)
+{
+    XcursorChunkHeader	chunkHeader;
+    XcursorImage	head;
+    XcursorImage	*image;
+    int			n;
+    XcursorPixel	*p;
+
+    if (!file || !fileHeader)
+        return NULL;
+
+    if (!_XcursorFileReadChunkHeader (file, fileHeader, toc, &chunkHeader))
+	return NULL;
+    if (!_XcursorReadUInt (file, &head.width))
+	return NULL;
+    if (!_XcursorReadUInt (file, &head.height))
+	return NULL;
+    if (!_XcursorReadUInt (file, &head.xhot))
+	return NULL;
+    if (!_XcursorReadUInt (file, &head.yhot))
+	return NULL;
+    if (!_XcursorReadUInt (file, &head.delay))
+	return NULL;
+    /* sanity check data */
+    if (head.width >= 0x10000 || head.height > 0x10000)
+	return NULL;
+    if (head.width == 0 || head.height == 0)
+	return NULL;
+    if (head.xhot > head.width || head.yhot > head.height)
+	return NULL;
+
+    /* Create the image and initialize it */
+    image = XcursorImageCreate (head.width, head.height);
+    if (chunkHeader.version < image->version)
+	image->version = chunkHeader.version;
+    image->size = chunkHeader.subtype;
+    image->xhot = head.xhot;
+    image->yhot = head.yhot;
+    image->delay = head.delay;
+    n = image->width * image->height;
+    p = image->pixels;
+    while (n--)
+    {
+	if (!_XcursorReadUInt (file, p))
+	{
+	    XcursorImageDestroy (image);
+	    return NULL;
+	}
+	p++;
+    }
+    return image;
+}
+
+static XcursorImages *
+XcursorXcFileLoadImages (XcursorFile *file, int size)
+{
+    XcursorFileHeader	*fileHeader;
+    XcursorDim		bestSize;
+    int			nsize;
+    XcursorImages	*images;
+    int			n;
+    int			toc;
+
+    if (!file || size < 0)
+	return NULL;
+    fileHeader = _XcursorReadFileHeader (file);
+    if (!fileHeader)
+	return NULL;
+    bestSize = _XcursorFindBestSize (fileHeader, (XcursorDim) size, &nsize);
+    if (!bestSize)
+    {
+        _XcursorFileHeaderDestroy (fileHeader);
+	return NULL;
+    }
+    images = XcursorImagesCreate (nsize);
+    if (!images)
+    {
+        _XcursorFileHeaderDestroy (fileHeader);
+	return NULL;
+    }
+    for (n = 0; n < nsize; n++)
+    {
+	toc = _XcursorFindImageToc (fileHeader, bestSize, n);
+	if (toc < 0)
+	    break;
+	images->images[images->nimage] = _XcursorReadImage (file, fileHeader,
+							    toc);
+	if (!images->images[images->nimage])
+	    break;
+	images->nimage++;
+    }
+    _XcursorFileHeaderDestroy (fileHeader);
+    if (images->nimage != nsize)
+    {
+	XcursorImagesDestroy (images);
+	images = NULL;
+    }
+    return images;
+}
+
+static int
+_XcursorStdioFileRead (XcursorFile *file, unsigned char *buf, int len)
+{
+    FILE    *f = file->closure;
+    return fread (buf, 1, len, f);
+}
+
+static int
+_XcursorStdioFileWrite (XcursorFile *file, unsigned char *buf, int len)
+{
+    FILE    *f = file->closure;
+    return fwrite (buf, 1, len, f);
+}
+
+static int
+_XcursorStdioFileSeek (XcursorFile *file, long offset, int whence)
+{
+    FILE    *f = file->closure;
+    return fseek (f, offset, whence);
+}
+
+static void
+_XcursorStdioFileInitialize (FILE *stdfile, XcursorFile *file)
+{
+    file->closure = stdfile;
+    file->read = _XcursorStdioFileRead;
+    file->write = _XcursorStdioFileWrite;
+    file->seek = _XcursorStdioFileSeek;
+}
+
+static XcursorImages *
+XcursorFileLoadImages (FILE *file, int size)
+{
+    XcursorFile	f;
+
+    if (!file)
+        return NULL;
+
+    _XcursorStdioFileInitialize (file, &f);
+    return XcursorXcFileLoadImages (&f, size);
+}
+
+/*
+ * From libXcursor/src/library.c
+ */
+
+#ifndef ICONDIR
+#define ICONDIR "/usr/X11R6/lib/X11/icons"
+#endif
+
+#ifndef XCURSORPATH
+#define XCURSORPATH "~/.icons:/usr/share/icons:/usr/share/pixmaps:"ICONDIR
+#endif
+
+static const char *
+XcursorLibraryPath (void)
+{
+    static const char	*path;
+
+    if (!path)
+    {
+	path = getenv ("XCURSOR_PATH");
+	if (!path)
+	    path = XCURSORPATH;
+    }
+    return path;
+}
+
+static  void
+_XcursorAddPathElt (char *path, const char *elt, int len)
+{
+    int	    pathlen = strlen (path);
+
+    /* append / if the path doesn't currently have one */
+    if (path[0] == '\0' || path[pathlen - 1] != '/')
+    {
+	strcat (path, "/");
+	pathlen++;
+    }
+    if (len == -1)
+	len = strlen (elt);
+    /* strip leading slashes */
+    while (len && elt[0] == '/')
+    {
+	elt++;
+	len--;
+    }
+    strncpy (path + pathlen, elt, len);
+    path[pathlen + len] = '\0';
+}
+
+static char *
+_XcursorBuildThemeDir (const char *dir, const char *theme)
+{
+    const char	    *colon;
+    const char	    *tcolon;
+    char	    *full;
+    char	    *home;
+    int		    dirlen;
+    int		    homelen;
+    int		    themelen;
+    int		    len;
+
+    if (!dir || !theme)
+        return NULL;
+
+    colon = strchr (dir, ':');
+    if (!colon)
+	colon = dir + strlen (dir);
+
+    dirlen = colon - dir;
+
+    tcolon = strchr (theme, ':');
+    if (!tcolon)
+	tcolon = theme + strlen (theme);
+
+    themelen = tcolon - theme;
+
+    home = NULL;
+    homelen = 0;
+    if (*dir == '~')
+    {
+	home = getenv ("HOME");
+	if (!home)
+	    return NULL;
+	homelen = strlen (home);
+	dir++;
+	dirlen--;
+    }
+
+    /*
+     * add space for any needed directory separators, one per component,
+     * and one for the trailing null
+     */
+    len = 1 + homelen + 1 + dirlen + 1 + themelen + 1;
+
+    full = malloc (len);
+    if (!full)
+	return NULL;
+    full[0] = '\0';
+
+    if (home)
+	_XcursorAddPathElt (full, home, -1);
+    _XcursorAddPathElt (full, dir, dirlen);
+    _XcursorAddPathElt (full, theme, themelen);
+    return full;
+}
+
+static char *
+_XcursorBuildFullname (const char *dir, const char *subdir, const char *file)
+{
+    char    *full;
+
+    if (!dir || !subdir || !file)
+        return NULL;
+
+    full = malloc (strlen (dir) + 1 + strlen (subdir) + 1 + strlen (file) + 1);
+    if (!full)
+	return NULL;
+    full[0] = '\0';
+    _XcursorAddPathElt (full, dir, -1);
+    _XcursorAddPathElt (full, subdir, -1);
+    _XcursorAddPathElt (full, file, -1);
+    return full;
+}
+
+static const char *
+_XcursorNextPath (const char *path)
+{
+    char    *colon = strchr (path, ':');
+
+    if (!colon)
+	return NULL;
+    return colon + 1;
+}
+
+#define XcursorWhite(c)	((c) == ' ' || (c) == '\t' || (c) == '\n')
+#define XcursorSep(c) ((c) == ';' || (c) == ',')
+
+static char *
+_XcursorThemeInherits (const char *full)
+{
+    char    line[8192];
+    char    *result = NULL;
+    FILE    *f;
+
+    if (!full)
+        return NULL;
+
+    f = fopen (full, "r");
+    if (f)
+    {
+	while (fgets (line, sizeof (line), f))
+	{
+	    if (!strncmp (line, "Inherits", 8))
+	    {
+		char    *l = line + 8;
+		char    *r;
+		while (*l == ' ') l++;
+		if (*l != '=') continue;
+		l++;
+		while (*l == ' ') l++;
+		result = malloc (strlen (l));
+		if (result)
+		{
+		    r = result;
+		    while (*l)
+		    {
+			while (XcursorSep(*l) || XcursorWhite (*l)) l++;
+			if (!*l)
+			    break;
+			if (r != result)
+			    *r++ = ':';
+			while (*l && !XcursorWhite(*l) &&
+			       !XcursorSep(*l))
+			    *r++ = *l++;
+		    }
+		    *r++ = '\0';
+		}
+		break;
+	    }
+	}
+	fclose (f);
+    }
+    return result;
+}
+
+static FILE *
+XcursorScanTheme (const char *theme, const char *name)
+{
+    FILE	*f = NULL;
+    char	*full;
+    char	*dir;
+    const char  *path;
+    char	*inherits = NULL;
+    const char	*i;
+
+    if (!theme || !name)
+        return NULL;
+
+    /*
+     * Scan this theme
+     */
+    for (path = XcursorLibraryPath ();
+	 path && f == NULL;
+	 path = _XcursorNextPath (path))
+    {
+	dir = _XcursorBuildThemeDir (path, theme);
+	if (dir)
+	{
+	    full = _XcursorBuildFullname (dir, "cursors", name);
+	    if (full)
+	    {
+		f = fopen (full, "r");
+		free (full);
+	    }
+	    if (!f && !inherits)
+	    {
+		full = _XcursorBuildFullname (dir, "", "index.theme");
+		if (full)
+		{
+		    inherits = _XcursorThemeInherits (full);
+		    free (full);
+		}
+	    }
+	    free (dir);
+	}
+    }
+    /*
+     * Recurse to scan inherited themes
+     */
+    for (i = inherits; i && f == NULL; i = _XcursorNextPath (i))
+	f = XcursorScanTheme (i, name);
+    if (inherits != NULL)
+	free (inherits);
+    return f;
+}
+
+XcursorImages *
+XcursorLibraryLoadImages (const char *file, const char *theme, int size)
+{
+    FILE	    *f = NULL;
+    XcursorImages   *images = NULL;
+
+    if (!file)
+        return NULL;
+
+    if (theme)
+	f = XcursorScanTheme (theme, file);
+    if (!f)
+	f = XcursorScanTheme ("default", file);
+    if (f)
+    {
+	images = XcursorFileLoadImages (f, size);
+	if (images)
+	    XcursorImagesSetName (images, file);
+	fclose (f);
+    }
+    return images;
+}
diff --git a/cursor/xcursor.h b/cursor/xcursor.h
new file mode 100644
index 0000000..a39c58e
--- /dev/null
+++ b/cursor/xcursor.h
@@ -0,0 +1,58 @@
+/*
+ * Copyright © 2002 Keith Packard
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that
+ * copyright notice and this permission notice appear in supporting
+ * documentation, and that the name of Keith Packard not be used in
+ * advertising or publicity pertaining to distribution of the software without
+ * specific, written prior permission.  Keith Packard makes no
+ * representations about the suitability of this software for any purpose.  It
+ * is provided "as is" without express or implied warranty.
+ *
+ * KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef _XCURSOR_H_
+#define _XCURSOR_H_
+
+typedef int		XcursorBool;
+typedef unsigned int	XcursorUInt;
+
+typedef XcursorUInt	XcursorDim;
+typedef XcursorUInt	XcursorPixel;
+
+typedef struct _XcursorImage {
+    XcursorUInt	    version;	/* version of the image data */
+    XcursorDim	    size;	/* nominal size for matching */
+    XcursorDim	    width;	/* actual width */
+    XcursorDim	    height;	/* actual height */
+    XcursorDim	    xhot;	/* hot spot x (must be inside image) */
+    XcursorDim	    yhot;	/* hot spot y (must be inside image) */
+    XcursorUInt	    delay;	/* animation delay to next frame (ms) */
+    XcursorPixel    *pixels;	/* pointer to pixels */
+} XcursorImage;
+
+/*
+ * Other data structures exposed by the library API
+ */
+typedef struct _XcursorImages {
+    int		    nimage;	/* number of images */
+    XcursorImage    **images;	/* array of XcursorImage pointers */
+    char	    *name;	/* name used to load images */
+} XcursorImages;
+
+XcursorImages *
+XcursorLibraryLoadImages (const char *file, const char *theme, int size);
+
+void
+XcursorImagesDestroy (XcursorImages *images);
+
+#endif