1 /* Copyright (C) 2001-2019 Artifex Software, Inc.
2 All Rights Reserved.
3
4 This software is provided AS-IS with no warranty, either express or
5 implied.
6
7 This software is distributed under license and may not be copied,
8 modified or distributed except as expressly authorized under the terms
9 of the license contained in the file LICENSE in this distribution.
10
11 Refer to licensing information at http://www.artifex.com or contact
12 Artifex Software, Inc., 1305 Grant Avenue - Suite 200, Novato,
13 CA 94945, U.S.A., +1(415)492-9861, for further information.
14 */
15
16
17 /* Glyph data cache methods. */
18
19 #include "gx.h"
20 #include "gserrors.h"
21 #include "memory_.h"
22 #include "gsstruct.h"
23 #include "gsgdata.h"
24 #include "gsgcache.h"
25 #include "gxfont.h"
26 #include "gxfont42.h"
27
28 /*
29 * This implementation hardcodes the type 42 font type.
30 * We could generalize it, but since CIDFontType 0 uses
31 * a PS procedure for reading glyphs, it is hardly applicable.
32 *
33 * The caching is mostly useful for glyphs with multiple components,
34 * but CIDFontType 0 has 2 components max, which are relatively seldom.
35 * Also it is low useful for fonts, which fully loaded into RAM.
36 * FAPI does not need a caching, because renderer pludins access
37 * font data through a file handle by own means.
38 *
39 * Due to all above, currently the caching is applied
40 * only while emulating CIDFontType 2 with a True Type file.
41 */
42
43 typedef struct gs_glyph_cache_elem_s gs_glyph_cache_elem;
44 struct gs_glyph_cache_elem_s {
45 gs_glyph_data_t gd;
46 uint glyph_index;
47 uint lock_count;
48 gs_glyph_cache_elem *next;
49 };
50 gs_private_st_composite(st_glyph_cache_elem, gs_glyph_cache_elem, "gs_glyph_cache_elem",
51 gs_glyph_cache_elem_enum_ptrs, gs_glyph_cache_elem_reloc_ptrs);
52
53 static
ENUM_PTRS_WITH(gs_glyph_cache_elem_enum_ptrs,gs_glyph_cache_elem * e)54 ENUM_PTRS_WITH(gs_glyph_cache_elem_enum_ptrs, gs_glyph_cache_elem *e)
55 {
56 index --;
57 if (index < ST_GLYPH_DATA_NUM_PTRS)
58 return ENUM_USING(st_glyph_data, &e->gd, sizeof(e->gd), index);
59 return 0;
60 }
61 ENUM_PTR(0, gs_glyph_cache_elem, next);
62 ENUM_PTRS_END
RELOC_PTRS_WITH(gs_glyph_cache_elem_reloc_ptrs,gs_glyph_cache_elem * e)63 static RELOC_PTRS_WITH(gs_glyph_cache_elem_reloc_ptrs, gs_glyph_cache_elem *e)
64 {
65 RELOC_PTR(gs_glyph_cache_elem, next);
66 RELOC_USING(st_glyph_data, &e->gd, sizeof(e->gd));
67 } RELOC_PTRS_END
68
69 struct gs_glyph_cache_s {
70 int total_size;
71 gs_glyph_cache_elem *list;
72 gs_memory_t *memory;
73 gs_font_type42 *pfont;
74 stream *s;
75 get_glyph_data_from_file read_data;
76 };
77 gs_private_st_ptrs4(st_glyph_cache, gs_glyph_cache, "gs_glyph_cache",
78 gs_glyph_cache_enum_ptrs, gs_glyph_cache_reloc_ptrs, list, memory, pfont, s);
79
80 GS_NOTIFY_PROC(gs_glpyh_cache__release);
81
82 gs_glyph_cache *
gs_glyph_cache__alloc(gs_font_type42 * pfont,stream * s,get_glyph_data_from_file read_data)83 gs_glyph_cache__alloc(gs_font_type42 *pfont, stream *s,
84 get_glyph_data_from_file read_data)
85 {
86 gs_memory_t *mem = pfont->memory->stable_memory;
87 gs_glyph_cache *gdcache = (gs_glyph_cache *)gs_alloc_struct(mem,
88 gs_glyph_cache, &st_glyph_cache, "gs_glyph_cache");
89 if (gdcache == 0)
90 return 0;
91 gdcache->total_size = 0;
92 gdcache->list = NULL;
93 gdcache->pfont = pfont;
94 gdcache->s = s;
95 /*
96 * The cache elements need to be in stable memory so they don't
97 * get removed by 'restore' (elements can be created at a different
98 * save level than the current level)
99 */
100 gdcache->memory = mem;
101 gdcache->read_data = read_data;
102 gs_font_notify_register((gs_font *)pfont, gs_glyph_cache__release, (void *)gdcache);
103 return gdcache;
104 }
105
106 int
gs_glyph_cache__release(void * data,void * event)107 gs_glyph_cache__release(void *data, void *event)
108 {
109 gs_glyph_cache *self = (gs_glyph_cache *)data;
110 gs_glyph_cache_elem *e = self->list;
111 gs_font_type42 *pfont = self->pfont;
112
113 while (e != NULL) {
114 gs_glyph_cache_elem *next_e;
115
116 next_e = e->next;
117 e->gd.procs->free(&e->gd, "gs_glyph_cache__release");
118 gs_free_object(self->memory, e, "gs_glyph_cache_elem__release");
119 e = next_e;
120 }
121 self->list = NULL;
122 gs_font_notify_unregister((gs_font *)pfont, gs_glyph_cache__release, (void *)self);
123 gs_free_object(self->memory, self, "gs_glyph_cache__release");
124 return 0;
125 }
126
127 static gs_glyph_cache_elem **
gs_glyph_cache_elem__locate(gs_glyph_cache * self,uint glyph_index)128 gs_glyph_cache_elem__locate(gs_glyph_cache *self, uint glyph_index)
129 { /* If not fond, returns an unlocked element. */
130 gs_glyph_cache_elem **e = &self->list, **p_unlocked = NULL;
131 int count = 0; /* debug purpose only */
132
133 for (; *e != 0; e = &(*e)->next, count++) {
134 if ((*e)->glyph_index == glyph_index) {
135 return e;
136 }
137 if ((*e)->lock_count == 0)
138 p_unlocked = e;
139 }
140 return p_unlocked;
141 }
142
143 static inline void
gs_glyph_cache_elem__move_to_head(gs_glyph_cache * self,gs_glyph_cache_elem ** pe)144 gs_glyph_cache_elem__move_to_head(gs_glyph_cache *self, gs_glyph_cache_elem **pe)
145 { gs_glyph_cache_elem *e = *pe;
146
147 *pe = e->next;
148 e->next = self->list;
149 self->list = e;
150 }
151
152 /* Manage the glyph data using the font's allocator. */
153 static void
gs_glyph_cache_elem__free_data(gs_glyph_data_t * pgd,client_name_t cname)154 gs_glyph_cache_elem__free_data(gs_glyph_data_t *pgd, client_name_t cname)
155 { gs_glyph_cache_elem *e = (gs_glyph_cache_elem *)pgd->proc_data;
156
157 e->lock_count--;
158 }
159 static int
gs_glyph_cache_elem__substring(gs_glyph_data_t * pgd,uint offset,uint size)160 gs_glyph_cache_elem__substring(gs_glyph_data_t *pgd, uint offset, uint size)
161 { gs_glyph_cache_elem *e = (gs_glyph_cache_elem *)pgd->proc_data;
162
163 e->lock_count++;
164 return_error(gs_error_unregistered); /* Unsupported; should not happen. */
165 }
166
167 static const gs_glyph_data_procs_t gs_glyph_cache_elem_procs = {
168 gs_glyph_cache_elem__free_data, gs_glyph_cache_elem__substring
169 };
170
171 int
gs_get_glyph_data_cached(gs_font_type42 * pfont,uint glyph_index,gs_glyph_data_t * pgd)172 gs_get_glyph_data_cached(gs_font_type42 *pfont, uint glyph_index, gs_glyph_data_t *pgd)
173 { gs_glyph_cache *gdcache = pfont->data.gdcache;
174 gs_glyph_cache_elem **pe = gs_glyph_cache_elem__locate(gdcache, glyph_index);
175 gs_glyph_cache_elem *e = NULL;
176
177 if (pe == NULL || (*pe)->glyph_index != glyph_index) {
178 int code;
179
180 if (pe != NULL && gdcache->total_size > 32767 /* arbitrary */ &&
181 (*pe)->lock_count <= 0) {
182 /* Release the element's data, and move it : */
183 e = *pe;
184 gdcache->total_size -= e->gd.bits.size + sizeof(*e);
185 e->gd.procs->free(&e->gd, "gs_get_glyph_data_cached");
186 gs_glyph_cache_elem__move_to_head(gdcache, pe);
187 } else {
188 /* Allocate new head element. */
189 e = (gs_glyph_cache_elem *)gs_alloc_struct(gdcache->memory,
190 gs_glyph_cache_elem, &st_glyph_cache_elem, "gs_glyph_cache_elem");
191 if (e == NULL)
192 return_error(gs_error_VMerror);
193 memset(e, 0, sizeof(*e));
194 e->next = gdcache->list;
195 gdcache->list = e;
196 e->gd.memory = gdcache->memory;
197 }
198 /* Load the element's data : */
199 code = (*gdcache->read_data)(pfont, gdcache->s, glyph_index, &e->gd);
200 if (code < 0)
201 return code;
202 gdcache->total_size += e->gd.bits.size + sizeof(*e);
203 e->glyph_index = glyph_index;
204 } else {
205 /* Move the element : */
206 e = *pe;
207 gs_glyph_cache_elem__move_to_head(gdcache, pe);
208 }
209 /* Copy data and set procs : */
210 pgd->bits = e->gd.bits;
211 pgd->proc_data = e;
212 pgd->procs = &gs_glyph_cache_elem_procs;
213 e->lock_count++;
214 return 0;
215 }
216