File: gsgcache.c

package info (click to toggle)
ghostscript 8.71~dfsg2-9+squeeze1
  • links: PTS, VCS
  • area: main
  • in suites: squeeze
  • size: 79,896 kB
  • ctags: 80,654
  • sloc: ansic: 501,432; sh: 25,689; python: 4,853; cpp: 3,633; perl: 3,597; tcl: 1,480; makefile: 1,187; lisp: 407; asm: 284; xml: 263; awk: 66; csh: 17; yacc: 15
file content (217 lines) | stat: -rw-r--r-- 6,856 bytes parent folder | download | duplicates (3)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
/* Copyright (C) 2001-2006 Artifex Software, Inc.
   All Rights Reserved.
  
   This software is provided AS-IS with no warranty, either express or
   implied.

   This software is distributed under license and may not be copied, modified
   or distributed except as expressly authorized under the terms of that
   license.  Refer to licensing information at http://www.artifex.com/
   or contact Artifex Software, Inc.,  7 Mt. Lassen Drive - Suite A-134,
   San Rafael, CA  94903, U.S.A., +1(415)492-9861, for further information.
*/

/* $Id: gsgcache.c 8250 2007-09-25 13:31:24Z giles $ */
/* Glyph data cache methods. */

#include "gx.h"
#include "gserrors.h"
#include "memory_.h"
#include "gsstruct.h"
#include "gsgdata.h"
#include "gsgcache.h"
#include "gxfont.h"
#include "gxfont42.h"

/* 
 * This implementation hardcodes the type 42 font type.
 * We could generalize it, but since CIDFontType 0 uses
 * a PS procedure for reading glyphs, it is hardly applicable.
 * 
 * The caching is mostly useful for glyphs with multiple components,
 * but CIDFontType 0 has 2 components max, which are relatively seldom.
 * Also it is low useful for fonts, which fully loaded into RAM.
 * FAPI does not need a caching, because renderer pludins access 
 * font data through a file handle by own means.
 *
 * Due to all above, currently the caching is applied
 * only while emulating CIDFontType 2 with a True Type file.
 */

typedef struct gs_glyph_cache_elem_s gs_glyph_cache_elem;
struct gs_glyph_cache_elem_s {
    gs_glyph_data_t gd;
    uint glyph_index;
    uint lock_count;
    gs_glyph_cache_elem *next;
};
gs_public_st_composite(st_glyph_cache_elem, gs_glyph_cache_elem, "gs_glyph_cache_elem",
    gs_glyph_cache_elem_enum_ptrs, gs_glyph_cache_elem_reloc_ptrs);

static 
ENUM_PTRS_WITH(gs_glyph_cache_elem_enum_ptrs, gs_glyph_cache_elem *e)
{
    index --;
    if (index < ST_GLYPH_DATA_NUM_PTRS)
	return ENUM_USING(st_glyph_data, &e->gd, sizeof(e->gd), index);
    return 0;
}
ENUM_PTR(0, gs_glyph_cache_elem, next);
ENUM_PTRS_END
static RELOC_PTRS_WITH(gs_glyph_cache_elem_reloc_ptrs, gs_glyph_cache_elem *e)
{
    RELOC_PTR(gs_glyph_cache_elem, next);
    RELOC_USING(st_glyph_data, &e->gd, sizeof(e->gd));
} RELOC_PTRS_END

struct gs_glyph_cache_s {
    int total_size;
    gs_glyph_cache_elem *list;
    gs_memory_t *memory;
    gs_font_type42 *pfont;
    stream *s;
    get_glyph_data_from_file read_data;
};
gs_private_st_ptrs4(st_glyph_cache, gs_glyph_cache, "gs_glyph_cache",
    gs_glyph_cache_enum_ptrs, gs_glyph_cache_reloc_ptrs, list, memory, pfont, s);

GS_NOTIFY_PROC(gs_glpyh_cache__release);

gs_glyph_cache *
gs_glyph_cache__alloc(gs_font_type42 *pfont, stream *s,
			get_glyph_data_from_file read_data)
{ 
    gs_memory_t *mem = pfont->memory->stable_memory;
    gs_glyph_cache *gdcache = (gs_glyph_cache *)gs_alloc_struct(mem,
	    gs_glyph_cache, &st_glyph_cache, "gs_glyph_cache");
    if (gdcache == 0)
	return 0;
    gdcache->total_size = 0;
    gdcache->list = NULL;
    gdcache->pfont = pfont;
    gdcache->s = s;
    /*
    * The cache elements need to be in stable memory so they don't
    * get removed by 'restore' (elements can be created at a different
    * save level than the current level)
    */
    gdcache->memory = mem;
    gdcache->read_data = read_data;
    gs_font_notify_register((gs_font *)pfont, gs_glyph_cache__release, (void *)gdcache);
    return gdcache;
}

int
gs_glyph_cache__release(void *data, void *event)
{   
    gs_glyph_cache *this = (gs_glyph_cache *)data;
    gs_glyph_cache_elem *e = this->list;
    gs_font_type42 *pfont = this->pfont;

    while (e != NULL) {
	gs_glyph_cache_elem *next_e;

	next_e = e->next;
	e->gd.procs->free(&e->gd, "gs_glyph_cache__release");
	gs_free_object(this->memory, e, "gs_glyph_cache_elem__release");
	e = next_e;
    }
    this->list = NULL; 
    gs_font_notify_unregister((gs_font *)pfont, gs_glyph_cache__release, (void *)this);
    gs_free_object(this->memory, this, "gs_glyph_cache__release");
    return 0;
}

static gs_glyph_cache_elem **
gs_glyph_cache_elem__locate(gs_glyph_cache *this, uint glyph_index)
{   /* If not fond, returns an unlocked element. */ 
    gs_glyph_cache_elem **e = &this->list, **p_unlocked = NULL;
    int count = 0; /* debug purpose only */

    for (; *e != 0; e = &(*e)->next, count++) {
	if ((*e)->glyph_index == glyph_index) {
	    return e;
	}
	if ((*e)->lock_count == 0)
	    p_unlocked = e;
    }
    return p_unlocked;
}

static inline void
gs_glyph_cache_elem__move_to_head(gs_glyph_cache *this, gs_glyph_cache_elem **pe)
{   gs_glyph_cache_elem *e = *pe;

    *pe = e->next;
    e->next = this->list;
    this->list = e;
}

/* Manage the glyph data using the font's allocator. */
static void
gs_glyph_cache_elem__free_data(gs_glyph_data_t *pgd, client_name_t cname)
{   gs_glyph_cache_elem *e = (gs_glyph_cache_elem *)pgd->proc_data;

    e->lock_count--;
}
static int
gs_glyph_cache_elem__substring(gs_glyph_data_t *pgd, uint offset, uint size)
{   gs_glyph_cache_elem *e = (gs_glyph_cache_elem *)pgd->proc_data;

    e->lock_count++;
    return_error(gs_error_unregistered); /* Unsupported; should not happen. */
}			       

static const gs_glyph_data_procs_t gs_glyph_cache_elem_procs = {
    gs_glyph_cache_elem__free_data, gs_glyph_cache_elem__substring
};

int 
gs_get_glyph_data_cached(gs_font_type42 *pfont, uint glyph_index, gs_glyph_data_t *pgd)
{   gs_glyph_cache *gdcache = pfont->data.gdcache;
    gs_glyph_cache_elem **pe = gs_glyph_cache_elem__locate(gdcache, glyph_index);
    gs_glyph_cache_elem *e = NULL;

    if (pe == NULL || (*pe)->glyph_index != glyph_index) {
	int code;

	if (pe != NULL && gdcache->total_size > 32767 /* arbitrary */ && 
			  (*pe)->lock_count <= 0) {
	    /* Release the element's data, and move it : */
	    e = *pe;
	    gdcache->total_size -= e->gd.bits.size + sizeof(*e);
	    e->gd.procs->free(&e->gd, "gs_get_glyph_data_cached");
	    gs_glyph_cache_elem__move_to_head(gdcache, pe);
	} else {
	    /* Allocate new head element. */
	    e = (gs_glyph_cache_elem *)gs_alloc_struct(gdcache->memory,
		gs_glyph_cache_elem, &st_glyph_cache_elem, "gs_glyph_cache_elem");
	    if (e == NULL)
		return_error(gs_error_VMerror);
	    memset(e, 0, sizeof(*e));
	    e->next = gdcache->list;
	    gdcache->list = e;
	    e->gd.memory = gdcache->memory;
	}
        /* Load the element's data : */
	code = (*gdcache->read_data)(pfont, gdcache->s, glyph_index, &e->gd);
	if (code < 0)
	    return code;
        gdcache->total_size += e->gd.bits.size + sizeof(*e);
	e->glyph_index = glyph_index;
    } else {
        /* Move the element : */
	e = *pe;
	gs_glyph_cache_elem__move_to_head(gdcache, pe);
    }
    /* Copy data and set procs : */
    pgd->bits = e->gd.bits;
    pgd->proc_data = e;
    pgd->procs = &gs_glyph_cache_elem_procs;
    e->lock_count++;
    return 0;
}