>>> OK. So how can an application find out that the font cache
>>> creation (or update) is very time consuming? Is it at least
>>> possible to catch the situation of a first run?
>>
>> current implementation assumes the users will runs fc-cache to
>> create caches before running. as such APIs isn't available at this
>> point, so no, it isn't. though we discussed a bit these days, if it
>> is wrong assumption, we may need to think about another way IMHO.
>
> Given that many applications that use fontconfig are ported to Windows
> today, the assumption of running `fc-cache' in advance is becoming
> much weaker IMHO – there is no longer a global fontconfig cache, since
> every program comes with its own stuff.[*] I hate this approach a lot,
> but we have to face the reality on this platform...
I propose to export an inner API, FcDirCacheValidConfig ().
I've attached the patch `0001-Export-FcDirCacheValidConfig'.
Currently there is no way for applications to detect
`fontconfig needs a long time' for cache updating.
There is also no way for applications to find out
whether font cache updating is necessary or not, in a short time.
The already exported FcDirCacheValid () API updates all caches.
In other words, it takes a long time when updating is necessary.
I've investigated the point where FcDirCacheValid () takes a long time.
As a result, I noticed that inner API, FcDirCacheValidConfig ()
does not take a long time, that is, it does not update the cache.
So applications can find out whether updating caches are
necessary or not by this function, in a short time.
I've attached `is_neccesary_update.cc' as a sample application
using this function.
It can display directories that require cache updates.
An application may be able to estimate `fontconfig needs a long time'
for cache updating, since it become to be able to find out the directories
that requires cache updates.
>From b46df92964e9b3c225c59efb6c1aa81dad28c874 Mon Sep 17 00:00:00 2001
From: Masamichi Hosoda <trueroad@xxxxxxxxxxx>
Date: Wed, 23 Nov 2016 20:57:49 +0900
Subject: [PATCH] Export FcDirCacheValidConfig ()
FcDirCacheValidConfig () does not update caches.
So applications can find out whether updating caches are
necessary or not by this function.
---
doc/fcdircache.fncs | 11 +++++++++++
fontconfig/fontconfig.h | 3 +++
src/fccache.c | 2 +-
3 files changed, 15 insertions(+), 1 deletion(-)
diff --git a/doc/fcdircache.fncs b/doc/fcdircache.fncs
index faeba29..6b1fe6c 100644
--- a/doc/fcdircache.fncs
+++ b/doc/fcdircache.fncs
@@ -41,6 +41,17 @@ Returns FcTrue if <parameter>dir</parameter> has an associated valid cache
file, else returns FcFalse
@@
+@RET@ FcBool
+@FUNC@ FcDirCacheValidConfig
+@TYPE1@ const FcChar8 * @ARG1@ dir
+@TYPE2@ FcConfig * @ARG2@ config
+@PURPOSE@ check directory cache without cache updating
+@DESC@
+Returns FcTrue if <parameter>dir</parameter> has an associated valid cache
+file, else returns FcFalse. This function does not update caches.
+@SINCE@ 2.12.2
+@@
+
@RET@ FcCache *
@FUNC@ FcDirCacheLoad
@TYPE1@ const FcChar8 * @ARG1@ dir
diff --git a/fontconfig/fontconfig.h b/fontconfig/fontconfig.h
index 5c72b22..6598a27 100644
--- a/fontconfig/fontconfig.h
+++ b/fontconfig/fontconfig.h
@@ -347,6 +347,9 @@ FcPublic FcBool
FcDirCacheValid (const FcChar8 *cache_file);
FcPublic FcBool
+FcDirCacheValidConfig (const FcChar8 *cache_file, FcConfig *config);
+
+FcPublic FcBool
FcDirCacheClean (const FcChar8 *cache_dir, FcBool verbose);
FcPublic void
diff --git a/src/fccache.c b/src/fccache.c
index 6f3c68a..0948482 100644
--- a/src/fccache.c
+++ b/src/fccache.c
@@ -844,7 +844,7 @@ FcDirCacheValidateHelper (FcConfig *config, int fd, struct stat *fd_stat, struct
return ret;
}
-static FcBool
+FcBool
FcDirCacheValidConfig (const FcChar8 *dir, FcConfig *config)
{
return FcDirCacheProcess (config, dir,
--
2.8.3
#include <cstdio>
#include <iostream>
#include <dirent.h>
#include <errno.h>
#include <sys/stat.h>
#include <fontconfig/fontconfig.h>
int check_cache (FcConfig *config);
int scan_dirs (FcStrList *list, FcConfig *config);
int scan_dir (const FcChar8 *dir, FcConfig *config);
int main ()
{
FcInitLoadConfig ();
FcConfig *config = FcConfigCreate ();
FcChar8 *default_conf = FcConfigFilename (NULL);
FcConfigParseAndLoad (config, default_conf, FcTrue);
FcStrFree (default_conf);
int ret = check_cache (config);
std::cout << std::endl << "font cache updating is ";
if (ret)
std::cout << "neccesary (" << ret << " dirs) " << std::endl;
else
std::cout << "not neccesary" << std::endl;
return 0;
}
int check_cache (FcConfig *config)
{
FcStrList *list = FcConfigGetConfigDirs (config);
int ret = scan_dirs (list, config);
FcStrListDone (list);
return ret;
}
int scan_dirs (FcStrList *list, FcConfig *config)
{
int ret = 0;
const FcChar8 *dir;
while ((dir = FcStrListNext (list)))
ret += scan_dir (dir, config);
return ret;
}
int scan_dir (const FcChar8 *dir, FcConfig *config)
{
std::cout << dir << " - " << std::flush;
struct stat statb;
if (stat ((char *)dir, &statb) == -1)
{
switch (errno)
{
case ENOENT:
case ENOTDIR:
std::cout << "no such directory" << std::endl;
return 0;
default:
perror ("");
return 0;
}
}
int ret = 0;
if (FcDirCacheValidConfig (dir, config))
{
std::cout << "valid" << std::endl;
}
else
{
std::cout << "***INVALID*** - neccesary updating" << std::endl;
ret++;
}
DIR *dp = opendir ((char*)dir);
struct dirent *dent;
while ((dent = readdir (dp)) != NULL)
{
if (dent->d_type == DT_DIR && dent->d_name[0] != '.')
{
std::string subdir ((char*)dir);
subdir += "/";
subdir += dent->d_name;
ret += scan_dir ((FcChar8*)subdir.c_str (), config);
}
}
closedir (dp);
return ret;
}
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