1/*
2 * Copyright (C) 2009 Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met:
7 *
8 *     * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *     * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 *     * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include "config.h"
32#include "WebFontInfo.h"
33#include "WebFontRenderStyle.h"
34
35#include <fontconfig/fontconfig.h>
36#include <string.h>
37#include <unicode/utf16.h>
38
39namespace WebKit {
40
41WebCString WebFontInfo::familyForChars(const WebUChar* characters, size_t numCharacters, const char* preferredLocale)
42{
43    FcCharSet* cset = FcCharSetCreate();
44    for (size_t i = 0; i < numCharacters; ++i) {
45        if (U16_IS_SURROGATE(characters[i])
46         && U16_IS_SURROGATE_LEAD(characters[i])
47         && i != numCharacters - 1
48         && U16_IS_TRAIL(characters[i + 1])) {
49              FcCharSetAddChar(cset, U16_GET_SUPPLEMENTARY(characters[i], characters[i+1]));
50          i++;
51        } else
52              FcCharSetAddChar(cset, characters[i]);
53    }
54    FcPattern* pattern = FcPatternCreate();
55
56    FcValue fcvalue;
57    fcvalue.type = FcTypeCharSet;
58    fcvalue.u.c = cset;
59    FcPatternAdd(pattern, FC_CHARSET, fcvalue, FcFalse);
60
61    fcvalue.type = FcTypeBool;
62    fcvalue.u.b = FcTrue;
63    FcPatternAdd(pattern, FC_SCALABLE, fcvalue, FcFalse);
64
65    if (preferredLocale) {
66        FcLangSet* langset = FcLangSetCreate();
67        FcLangSetAdd(langset, reinterpret_cast<const FcChar8 *>(preferredLocale));
68        FcPatternAddLangSet(pattern, FC_LANG, langset);
69        FcLangSetDestroy(langset);
70    }
71
72    FcConfigSubstitute(0, pattern, FcMatchPattern);
73    FcDefaultSubstitute(pattern);
74
75    FcResult result;
76    FcFontSet* fontSet = FcFontSort(0, pattern, 0, 0, &result);
77    FcPatternDestroy(pattern);
78    FcCharSetDestroy(cset);
79
80    if (!fontSet)
81        return WebCString();
82
83    // Older versions of fontconfig have a bug where they cannot select
84    // only scalable fonts so we have to manually filter the results.
85    for (int i = 0; i < fontSet->nfont; ++i) {
86        FcPattern* current = fontSet->fonts[i];
87        FcBool isScalable;
88
89        if (FcPatternGetBool(current, FC_SCALABLE, 0, &isScalable) != FcResultMatch
90            || !isScalable)
91            continue;
92
93        // fontconfig can also return fonts which are unreadable
94        FcChar8* cFilename;
95        if (FcPatternGetString(current, FC_FILE, 0, &cFilename) != FcResultMatch)
96            continue;
97
98        if (access(reinterpret_cast<char*>(cFilename), R_OK))
99            continue;
100
101        FcChar8* family;
102        WebCString result;
103        if (FcPatternGetString(current, FC_FAMILY, 0, &family) == FcResultMatch) {
104            const char* charFamily = reinterpret_cast<char*>(family);
105            result = WebCString(charFamily, strlen(charFamily));
106        }
107        FcFontSetDestroy(fontSet);
108        return result;
109    }
110
111    FcFontSetDestroy(fontSet);
112    return WebCString();
113}
114
115void WebFontInfo::renderStyleForStrike(const char* family, int sizeAndStyle, WebFontRenderStyle* out)
116{
117    bool isBold = sizeAndStyle & 1;
118    bool isItalic = sizeAndStyle & 2;
119    int pixelSize = sizeAndStyle >> 2;
120
121    FcPattern* pattern = FcPatternCreate();
122    FcValue fcvalue;
123
124    fcvalue.type = FcTypeString;
125    fcvalue.u.s = reinterpret_cast<const FcChar8 *>(family);
126    FcPatternAdd(pattern, FC_FAMILY, fcvalue, FcFalse);
127
128    fcvalue.type = FcTypeInteger;
129    fcvalue.u.i = isBold ? FC_WEIGHT_BOLD : FC_WEIGHT_NORMAL;
130    FcPatternAdd(pattern, FC_WEIGHT, fcvalue, FcFalse);
131
132    fcvalue.type = FcTypeInteger;
133    fcvalue.u.i = isItalic ? FC_SLANT_ITALIC : FC_SLANT_ROMAN;
134    FcPatternAdd(pattern, FC_SLANT, fcvalue, FcFalse);
135
136    fcvalue.type = FcTypeBool;
137    fcvalue.u.b = FcTrue;
138    FcPatternAdd(pattern, FC_SCALABLE, fcvalue, FcFalse);
139
140    fcvalue.type = FcTypeDouble;
141    fcvalue.u.d = pixelSize;
142    FcPatternAdd(pattern, FC_SIZE, fcvalue, FcFalse);
143
144    FcConfigSubstitute(0, pattern, FcMatchPattern);
145    FcDefaultSubstitute(pattern);
146
147    FcResult result;
148    // Some versions of fontconfig don't actually write a value into result.
149    // However, it's not clear from the documentation if result should be a
150    // non-0 pointer: future versions might expect to be able to write to
151    // it. So we pass in a valid pointer and ignore it.
152    FcPattern* match = FcFontMatch(0, pattern, &result);
153    FcPatternDestroy(pattern);
154
155    out->setDefaults();
156
157    if (!match) {
158        FcPatternDestroy(match);
159        return;
160    }
161
162    FcBool b;
163    int i;
164
165    if (FcPatternGetBool(match, FC_ANTIALIAS, 0, &b) == FcResultMatch)
166        out->useAntiAlias = b;
167    if (FcPatternGetBool(match, FC_EMBEDDED_BITMAP, 0, &b) == FcResultMatch)
168        out->useBitmaps = b;
169    if (FcPatternGetBool(match, FC_AUTOHINT, 0, &b) == FcResultMatch)
170        out->useAutoHint = b;
171    if (FcPatternGetBool(match, FC_HINTING, 0, &b) == FcResultMatch)
172        out->useHinting = b;
173    if (FcPatternGetInteger(match, FC_HINT_STYLE, 0, &i) == FcResultMatch)
174        out->hintStyle = i;
175    if (FcPatternGetInteger(match, FC_RGBA, 0, &i) == FcResultMatch) {
176        switch (i) {
177        case FC_RGBA_NONE:
178            out->useSubpixel = 0;
179            break;
180        case FC_RGBA_RGB:
181        case FC_RGBA_BGR:
182        case FC_RGBA_VRGB:
183        case FC_RGBA_VBGR:
184            out->useSubpixel = 1;
185            break;
186        default:
187            // This includes FC_RGBA_UNKNOWN.
188            out->useSubpixel = 2;
189            break;
190        }
191    }
192
193    FcPatternDestroy(match);
194}
195
196} // namespace WebKit
197