x11: add window icon

The png file added to etc/ are taken from the link mentioned in commit
303096b, except that they have been converted to 16 bit, sRGB (with
color profile info dropped, if there was one), and transparent pixels
reset for better compression.

The file x11_icon.bin is generated by gen-x11-icon.sh. I'm adding it to
the git repo directly, because the script requires ImageMagick, and we
don't want to make building even more complicated.

The way how this is done is basically a compromise between effort
required in x11_common.c and in gen-x11-icon.sh. Ideally, x11_icon.bin
would be directly in the format as required by _NET_WM_ICON, but trying
to write the binary width/height values from shell would probably be a
nightmare, so here we go.

The zlib code in x11_common.c is lifted from demux_mkv.c, with some
modifications (like accepting a gzip header, because I don't know how to
make gzip write raw compressed data).

.gitignore

@@ -14,7 +14,7 @@
 /tags
 /TAGS
 /video/out/gl_video_shaders.h
-/video/out/vdpau_template.c
+/video/out/x11_icon.inc
 /demux/ebml_defs.c
 /demux/ebml_types.h
 /sub/osd_font.h

Makefile

@@ -373,6 +373,10 @@ video/out/gl_video.c: video/out/gl_video_shaders.h
 video/out/gl_video_shaders.h: TOOLS/file2string.pl video/out/gl_video_shaders.glsl
 	./$^ >$@
 
+video/out/x11_common.c: video/out/x11_icon.inc
+video/out/x11_icon.inc: TOOLS/file2string.pl video/out/x11_icon.bin
+	./$^ >$@
+
 sub/osd_libass.c: sub/osd_font.h
 sub/osd_font.h: TOOLS/file2string.pl sub/osd_font.otf
 	./$^ >$@
@@ -446,6 +450,7 @@ clean:
 	-$(RM) video/out/vdpau_template.c
 	-$(RM) demux/ebml_types.h demux/ebml_defs.c
 	-$(RM) video/out/gl_video_shaders.h
+	-$(RM) video/out/x11_icon.inc
 	-$(RM) sub/osd_font.h
 
 distclean: clean

TOOLS/gen-x11-icon.sh

@@ -0,0 +1,15 @@
+#!/bin/sh
+
+# This script is expected to be called as TOOLS/gen-x11-icon.sh (it will access
+# etc/mpv-icon...), and it will write video/out/x11_icon.bin.
+
+conv() {
+    echo
+    identify -format "icon: %w %h" $1
+    convert $1 -depth 8 rgba:-
+}
+
+(echo "# File generated by gen-x11-icon.sh" ;
+ conv etc/mpv-icon-8bit-16x16.png ;
+ conv etc/mpv-icon-8bit-32x32.png ;
+ conv etc/mpv-icon-8bit-64x64.png) | gzip -c > video/out/x11_icon.bin

video/out/x11_common.c

@@ -66,6 +66,10 @@
 #include <X11/XF86keysym.h>
 #endif
 
+#if CONFIG_ZLIB
+#include <zlib.h>
+#endif
+
 #include "mpvcore/input/input.h"
 #include "mpvcore/input/keycodes.h"
 
@@ -128,6 +132,10 @@ typedef struct
     long state;
 } MotifWmHints;
 
+static const char x11_icon[] =
+#include "video/out/x11_icon.inc"
+;
+
 static void vo_x11_update_geometry(struct vo *vo);
 static void vo_x11_fullscreen(struct vo *vo);
 static int vo_x11_get_fs_type(struct vo *vo);
@@ -371,6 +379,7 @@ static void init_atoms(struct vo_x11_state *x11)
     XA_INIT(_NET_WM_PID);
     XA_INIT(_NET_WM_NAME);
     XA_INIT(_NET_WM_ICON_NAME);
+    XA_INIT(_NET_WM_ICON);
     XA_INIT(_WIN_PROTOCOLS);
     XA_INIT(_WIN_LAYER);
     XA_INIT(_WIN_HINTS);
@@ -945,6 +954,100 @@ static void vo_x11_update_window_title(struct vo *vo)
     vo_x11_set_property_utf8(vo, x11->XA_NET_WM_ICON_NAME, title);
 }
 
+#if CONFIG_ZLIB
+static bstr decompress_gz(bstr in)
+{
+    bstr res = {0};
+    z_stream zstream;
+    uint8_t *dest;
+    size_t size = in.len;
+    int result;
+
+    zstream.zalloc = (alloc_func) 0;
+    zstream.zfree = (free_func) 0;
+    zstream.opaque = (voidpf) 0;
+    // 32 for gzip header, 15 for max. window bits
+    if (inflateInit2(&zstream, 32 + 15) != Z_OK)
+        goto error;
+    zstream.next_in = (Bytef *) in.start;
+    zstream.avail_in = size;
+
+    dest = NULL;
+    zstream.avail_out = size;
+    do {
+        size += 4000;
+        dest = talloc_realloc_size(NULL, dest, size);
+        zstream.next_out = (Bytef *) (dest + zstream.total_out);
+        result = inflate(&zstream, Z_NO_FLUSH);
+        if (result != Z_OK && result != Z_STREAM_END) {
+            talloc_free(dest);
+            dest = NULL;
+            inflateEnd(&zstream);
+            goto error;
+        }
+        zstream.avail_out += 4000;
+    } while (zstream.avail_out == 4000 && zstream.avail_in != 0
+             && result != Z_STREAM_END);
+
+    size = zstream.total_out;
+    inflateEnd(&zstream);
+
+    res.start = dest;
+    res.len = size;
+error:
+    return res;
+}
+#else
+static bstr decompress_gz(bstr in)
+{
+    return (bstr){0};
+}
+#endif
+
+#define MAX_ICONS 10
+
+static void vo_x11_set_wm_icon(struct vo_x11_state *x11)
+{
+    int num_icons = 0;
+    void *icon_data[MAX_ICONS];
+    int icon_w[MAX_ICONS], icon_h[MAX_ICONS];
+
+    bstr uncompressed = decompress_gz((bstr){(char *)x11_icon, sizeof(x11_icon)});
+    bstr data = uncompressed;
+    while (data.len && num_icons < MAX_ICONS) {
+        bstr line = bstr_getline(data, &data);
+        if (bstr_eatstart0(&line, "icon: ")) {
+            int w, h;
+            if (bstr_sscanf(line, "%d %d", &w, &h) == 2) {
+                int size = w * h * 4;
+                icon_w[num_icons] = w;
+                icon_h[num_icons] = h;
+                icon_data[num_icons] = data.start;
+                num_icons++;
+                data = bstr_cut(data, size);
+            }
+        }
+    }
+
+    size_t icon_size = 0;
+    for (int n = 0; n < num_icons; n++)
+        icon_size += sizeof(long) * (2 + icon_w[n] * icon_h[n]);
+    long *icon = talloc_array(NULL, long, icon_size);
+    long *cur = icon;
+    for (int n = 0; n < num_icons; n++) {
+        *cur++ = icon_w[n];
+        *cur++ = icon_h[n];
+        uint32_t *src = icon_data[n];
+        for (int i = 0; i < icon_h[n] * icon_w[n]; i++)
+            *cur++ = src[i];
+    }
+
+    XChangeProperty(x11->display, x11->window, x11->XA_NET_WM_ICON,
+                    XA_CARDINAL, 32, PropModeReplace, (char *)icon, icon_size);
+    talloc_free(icon);
+    talloc_free(uncompressed.start);
+}
+
 static void find_default_visual(struct vo_x11_state *x11, XVisualInfo *vis)
 {
     Display *display = x11->display;
@@ -994,6 +1097,7 @@ static void vo_x11_create_window(struct vo *vo, XVisualInfo *vis, int x, int y,
                          XNFocusWindow, x11->window,
                          NULL);
 
+    vo_x11_set_wm_icon(x11);
     vo_x11_update_window_title(vo);
 }
 

video/out/x11_common.h

@@ -117,6 +117,7 @@ struct vo_x11_state {
     Atom XA_NET_WM_PID;
     Atom XA_NET_WM_NAME;
     Atom XA_NET_WM_ICON_NAME;
+    Atom XA_NET_WM_ICON;
     Atom XA_WIN_PROTOCOLS;
     Atom XA_WIN_LAYER;
     Atom XA_WIN_HINTS;