1/*
2* Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
3* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4*
5* This code is free software; you can redistribute it and/or modify it
6* under the terms of the GNU General Public License version 2 only, as
7* published by the Free Software Foundation.
8*
9* This code is distributed in the hope that it will be useful, but WITHOUT
10* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11* FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12* version 2 for more details (a copy is included in the LICENSE file that
13* accompanied this code).
14*
15* You should have received a copy of the GNU General Public License version
16* 2 along with this work; if not, write to the Free Software Foundation,
17* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18*
19* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20* or visit www.oracle.com if you need additional information or have any
21* questions.
22*/
23
24#include "systemScale.h"
25#include "jni.h"
26#include "jni_util.h"
27#include "jvm_md.h"
28#include <dlfcn.h>
29#include <stdio.h>
30#include <stdlib.h>
31#include <string.h>
32
33typedef void* g_settings_schema_source_get_default();
34typedef void* g_settings_schema_source_ref(void *);
35typedef void g_settings_schema_source_unref(void *);
36typedef void* g_settings_schema_source_lookup(void *, char *, int);
37typedef int g_settings_schema_has_key(void *, char *);
38typedef void* g_settings_new_full(void *, void *, char *);
39typedef void* g_settings_get_value(void *, char *);
40typedef int g_variant_is_of_type(void *, char *);
41typedef unsigned long g_variant_n_children(void *);
42typedef void* g_variant_get_child_value(void *, unsigned long);
43typedef void  g_variant_unref(void *);
44typedef char*  g_variant_get_string(void *, unsigned long *);
45typedef int  g_variant_get_int32(void *);
46typedef double  g_variant_get_double(void *);
47
48static g_settings_schema_has_key* fp_g_settings_schema_has_key;
49static g_settings_new_full* fp_g_settings_new_full;
50static g_settings_get_value* fp_g_settings_get_value;
51static g_variant_is_of_type* fp_g_variant_is_of_type;
52static g_variant_n_children* fp_g_variant_n_children;
53static g_variant_get_child_value* fp_g_variant_get_child_value;
54static g_variant_get_string* fp_g_variant_get_string;
55static g_variant_get_int32* fp_g_variant_get_int32;
56static g_variant_get_double* fp_g_variant_get_double;
57static g_variant_unref* fp_g_variant_unref;
58
59static void* get_schema_value(char *name, char *key) {
60    static void *lib_handle;
61    static int initialized = 0;
62    static void * default_schema;
63    static g_settings_schema_source_lookup* schema_lookup;
64    void *schema = NULL, *fp = NULL;
65    if (!initialized) {
66        initialized = 1;
67        lib_handle = dlopen(JNI_LIB_NAME("gio-2.0"), RTLD_GLOBAL | RTLD_LAZY);
68        if (!lib_handle) {
69            CHECK_NULL_RETURN(lib_handle =
70                          dlopen(VERSIONED_JNI_LIB_NAME("gio-2.0", "0"),
71                                                RTLD_GLOBAL | RTLD_LAZY), NULL);
72        }
73        CHECK_NULL_RETURN(fp_g_settings_schema_has_key =
74                          (g_settings_schema_has_key*)
75                          dlsym(lib_handle, "g_settings_schema_has_key"), NULL);
76        CHECK_NULL_RETURN(fp_g_settings_new_full =
77                          (g_settings_new_full*)
78                          dlsym(lib_handle, "g_settings_new_full"), NULL);
79        CHECK_NULL_RETURN(fp_g_settings_get_value =
80                          (g_settings_get_value*)
81                          dlsym(lib_handle, "g_settings_get_value"), NULL);
82        CHECK_NULL_RETURN(fp_g_variant_is_of_type =
83                          (g_variant_is_of_type*)
84                          dlsym(lib_handle, "g_variant_is_of_type"), NULL);
85        CHECK_NULL_RETURN(fp_g_variant_n_children =
86                          (g_variant_n_children*)
87                          dlsym(lib_handle, "g_variant_n_children"), NULL);
88        CHECK_NULL_RETURN(fp_g_variant_get_child_value =
89                          (g_variant_get_child_value*)
90                          dlsym(lib_handle, "g_variant_get_child_value"), NULL);
91        CHECK_NULL_RETURN(fp_g_variant_get_string =
92                          (g_variant_get_string*)
93                          dlsym(lib_handle, "g_variant_get_string"), NULL);
94        CHECK_NULL_RETURN(fp_g_variant_get_int32 =
95                          (g_variant_get_int32*)
96                          dlsym(lib_handle, "g_variant_get_int32"), NULL);
97        CHECK_NULL_RETURN(fp_g_variant_get_double =
98                          (g_variant_get_double*)
99                          dlsym(lib_handle, "g_variant_get_double"), NULL);
100        CHECK_NULL_RETURN(fp_g_variant_unref =
101                          (g_variant_unref*)
102                          dlsym(lib_handle, "g_variant_unref"), NULL);
103
104        fp = dlsym(lib_handle, "g_settings_schema_source_get_default");
105        if (fp) {
106            default_schema = ((g_settings_schema_source_get_default*)fp)();
107        }
108        if (default_schema) {
109            fp = dlsym(lib_handle, "g_settings_schema_source_ref");
110            if (fp) {
111                ((g_settings_schema_source_ref*)fp)(default_schema);
112            }
113        }
114        schema_lookup = (g_settings_schema_source_lookup*)
115                           dlsym(lib_handle, "g_settings_schema_source_lookup");
116    }
117
118    if (!default_schema || !schema_lookup) {
119        return NULL;
120    }
121
122    schema = schema_lookup(default_schema, name, 1);
123    if (schema) {
124        if (fp_g_settings_schema_has_key(schema, key)) {
125            void *settings = fp_g_settings_new_full(schema, NULL, NULL);
126            if (settings) {
127                return fp_g_settings_get_value(settings, key);
128            }
129        }
130    }
131    return NULL;
132}
133
134
135static double getDesktopScale(char *output_name) {
136    double result = -1;
137    if(output_name) {
138        void *value = get_schema_value("com.ubuntu.user-interface",
139                                                                "scale-factor");
140        if (value) {
141            if(fp_g_variant_is_of_type(value, "a{si}")) {
142                int num = fp_g_variant_n_children(value);
143                int i = 0;
144                while (i < num) {
145                    void *entry = fp_g_variant_get_child_value(value, i++);
146                    if (entry) {
147                        void *screen = fp_g_variant_get_child_value(entry, 0);
148                        void *scale = fp_g_variant_get_child_value(entry, 1);
149                        if (screen && scale) {
150                            char *name = fp_g_variant_get_string(screen, NULL);
151                            if (name && !strcmp(name, output_name)) {
152                                result = fp_g_variant_get_int32(scale) / 8.;
153                            }
154                            fp_g_variant_unref(screen);
155                            fp_g_variant_unref(scale);
156                        }
157                        fp_g_variant_unref(entry);
158                    }
159                    if (result > 0) {
160                        break;
161                    }
162                }
163            }
164            fp_g_variant_unref(value);
165        }
166        if (result > 0) {
167            value = get_schema_value("com.canonical.Unity.Interface",
168                                                           "text-scale-factor");
169            if (value && fp_g_variant_is_of_type(value, "d")) {
170                result *= fp_g_variant_get_double(value);
171                fp_g_variant_unref(value);
172            }
173        }
174    }
175
176    if (result <= 0) {
177        void *value = get_schema_value("org.gnome.desktop.interface",
178                                                         "text-scaling-factor");
179        if (value && fp_g_variant_is_of_type(value, "d")) {
180            result = fp_g_variant_get_double(value);
181            fp_g_variant_unref(value);
182        }
183    }
184
185    return result;
186
187}
188
189static int getScale(const char *name) {
190    char *uiScale = getenv(name);
191    if (uiScale != NULL) {
192        double scale = strtod(uiScale, NULL);
193        if (scale < 1) {
194            return -1;
195        }
196        return (int) scale;
197    }
198    return -1;
199}
200
201double getNativeScaleFactor(char *output_name) {
202    static int scale = -2.0;
203    double native_scale = 0;
204    int gdk_scale = 0;
205
206    if (scale == -2) {
207        scale = getScale("J2D_UISCALE");
208    }
209
210    if (scale > 0) {
211        return scale;
212    }
213
214    native_scale = getDesktopScale(output_name);
215
216    if (native_scale <= 0) {
217        native_scale = 1;
218    }
219
220    gdk_scale = getScale("GDK_SCALE");
221
222    return gdk_scale > 0 ? native_scale * gdk_scale : native_scale;
223}
224