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diff --git a/docs/docbook/devdoc/gencache.xml b/docs/docbook/devdoc/gencache.xml deleted file mode 100644 index 1ba2f77c9d4..00000000000 --- a/docs/docbook/devdoc/gencache.xml +++ /dev/null @@ -1,119 +0,0 @@ -<chapter id="gencache"> -<chapterinfo> - <author> - <firstname>Rafal</firstname><surname>Szczesniak</surname> - </author> - <pubdate>April 2003</pubdate> -</chapterinfo> - -<title>General cache mechanism and API</title> - -<sect1> -<title>Abstract</title> -<para> -General cache (gencache) was designed to combine various kinds of caching -mechanisms into one, defined by a simple API. This way, anyone can use it -to create their own caching layer on top of gencache. An example of -such approach is the netbios name cache. -</para> -</sect1> - -<sect1> -<title>The mechanism</title> -<para> -Gencache utilises <emphasise>tdb</emphasise> database, like many other -parts of Samba. As its origins are in Berkeley DB implementation, it -uses key/value pairs stored in binary file. The values gencache -operates on are string-based, however. This makes very easy to use it -in command line environment eg. to quickly take a look at what's in -the cache or set some value. -</para> - -<para> -All the data is stored in <filename>gencache.tdb</filename> -file. Records put there are in key/value format as mentioned below, -but as it's a cache, the timeout plays also important role and has a -special place in the key/value pair, as well as API. -</para> -</sect1> - - -<sect1> -<title>The data structure</title> -<para> -The record stored in <filename>gencache.tdb</filename> file consists -of the key, the value and the expiration timeout. While the first part -is stored completely independent from the others, the last two are -kept together. The form the record has is: -</para> - -<para><programlisting> -key: <string&bt; -value: <12-digit timeout&bt;/<string> -</programlisting></para> - -<para>The timeout part is the ASCII representation of -<emphasis>time_t</emphasis> value of the time when the cache entry -expires. Obviously the API, the programmer is provided with, hides this detail, -so that you don't have to care about checking it. Simply watch -carefully the return status of the function. -</para> -</sect1> - -<sect1> -<title>The API</title> - -<para><programlisting> -BOOL gencache_init() -</programlisting></para> - -<para>This is used to initialise to whole caching mechanism. It means -opening the file or creating it if non-existing. If it's already been -opened earlier, then the routine just does nothing and returns -<constant>true</constant>. If something goes wrong, say the user -doesn't have necessary rights, the function returns -<constant>false</constant>.</para> - -<para><programlisting> -BOOL gencache_shutdown() -</programlisting></para> - -<para>This is the proper way to close the cache file. It simply -returns <constant>true</constant> after successful closing file and -<constant>false</constant> upon a failure.</para> - -<para><programlisting> -BOOL gencache_set(const char* keystr, const char* value, time_t timeout) -</programlisting></para> - -<para>This is one of the most basic functions. What it allows you to -do is to set some particular cache entry. If the entry haven't -existed yet, the function will act just as it was "gencache_add" -function. If it's already been in the cache, the entry will be set to -the new value. In either case, the cache entry will be set with given -key, value and timeout. Thus it is comfortable way to just set the -entry and not care about the details.</para> - -<para><programlisting> -BOOL gencache_set_only(const char* keystr, const char* value, time_t timeout) -</programlisting></para> - -<para><programlisting> -BOOL gencache_del(const char* keystr) -</programlisting></para> - -<para><programlisting> -BOOL gencache_get(const char* keystr, char** valstr, time_t* timeout) -</programlisting></para> - -<para><programlisting> -void gencache_iterate(void (*fn)(const char* key, const char *value, time_t timeout, void* dptr), - void* data, const char* keystr_pattern) - -</programlisting></para> - -<sect1> -<title>Writing your own caching layer</title> -</sect1> - -</chapter> |