#include <XrdOucCache2.hh>
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virtual XrdOucCacheIO2 * | Attach (XrdOucCacheIO2 *ioP, int opts=0)=0 |
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virtual XrdOucCacheIO * | Attach (XrdOucCacheIO *ioP, int opts=0) |
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virtual XrdOucCache * | Create (Parms &Params, XrdOucCacheIO::aprParms *aprP=0) |
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virtual void | EnvInfo (XrdOucEnv &theEnv) |
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virtual int | LocalFilePath (const char *url, char *buff=0, int blen=0, LFP_Reason why=ForAccess, bool forall=false) |
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virtual int | Prepare (const char *url, int oflags, mode_t mode) |
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virtual int | Stat (const char *url, struct stat &sbuff) |
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| XrdOucCache2 () |
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virtual | ~XrdOucCache2 () |
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virtual XrdOucCacheIO * | Attach (XrdOucCacheIO *ioP, int Options=0)=0 |
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virtual int | isAttached () |
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virtual int | Unlink (const char *) |
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virtual int | Rmdir (const char *) |
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virtual int | Rename (const char *, const char *) |
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virtual int | Truncate (const char *, off_t) |
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| XrdOucCache () |
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virtual | ~XrdOucCache () |
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The XrdOucCache2 class is used to define a version 2 cache. In version 2, there can be only one such instance. the cache is associated with one or more XrdOucCacheIO2 objects. Use the Attach() method in this class to create such associations.
◆ LFP_Reason
Get the path to a file that is complete in the local cache. By default, the file must be complete in the cache (i.e. no blocks are missing). This can be overridden. Thes path can be used to access the file on the local node.
- Parameters
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url | - Pointer to the url of interest. |
buff | - Pointer to a buffer to receive the local path to the file. If nil, no path is returned. |
blen | - Length of the buffer, buff. If zero, no path is returned. |
why | - One of the LFP_Reason enums describing the call: ForAccess - the path will be used to access the file. If the file is complete, the system will delay purging the file for a configurable window, should a purge be imminent. A null path is returned for any non-zero return code. ForInfo - same as ForAccess except that purging will not be delayed if imminent. A path is always returned, if possible. Otherwise the first byte of any supplied buffer is set to 0. ForPath - Only the path is wanted and no checks need be performed. The only possible errors are -EINVAL and -ENAMETOOLONG. |
forall | - When ForAccess is specified: when true makes the file world readable; otherwise, only group readable. The parameter is ignored unless "why" is ForAccess and a local file path is requested to be returned. |
- Returns
- 0 - the file is complete and the local path to the file is in the buffer, if it has been supllied.
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<0 - the request could not be fulfilled. The return value is -errno describing why. If a buffer was supplied and a path could be generated it is returned only if "why" is ForInfo or ForPath. Otherwise, a null path is returned.
Common return codes are: -EINVAL an argument is invalid. -EISDIR target is a directory not a file. -ENAMETOOLONG buffer not big enough to hold path. -ENOENT file not in cache -ENOTSUP method not implemented -EREMOTE file is incomplete
- Returns
- >0 - Reserved for future use.
Enumerator |
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ForAccess | |
ForInfo | |
ForPath | |
◆ XrdOucCache2()
XrdOucCache2::XrdOucCache2 |
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inline |
◆ ~XrdOucCache2()
virtual XrdOucCache2::~XrdOucCache2 |
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inlinevirtual |
◆ Attach() [1/3]
Obtain a new XrdOucCacheIO2 object that fronts an existing XrdOucCacheIO2 with this cache. Upon success a pointer to a new XrdOucCacheIO2 object is returned and must be used to read and write data with the cache interposed. Upon failure, the original XrdOucCacheIO2 object is returned with errno set. You can continue using the object without any cache. The new cache should use the methods in the passed CacheIO2 object to perform I/O operatios.
- Parameters
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ioP | Pointer to the current CacheIO2 object used for I/O. |
opts | Cache options identical to those defined for XrdOucCache Attach() method. |
- Returns
- Pointer to a new XrdOucCacheIO2 object (success) or the original XrdOucCacheIO2 object (failure) with errno set.
◆ Attach() [2/3]
◆ Attach() [3/3]
◆ Create()
Creates an instance of a version 1 cache. This method is no longer used so we simply define a default for this method here for backward compatability.
- Returns
- A pointer to an XrdOucCache object upon success or a nil pointer with errno set upon failure.
Implements XrdOucCache.
◆ EnvInfo()
virtual void XrdOucCache2::EnvInfo |
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XrdOucEnv & |
theEnv | ) |
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inlinevirtual |
Supply environmental information to the cache. This is only called on the server but is optional and might not be called. When it is called, it is gauranteed to occur before any active use of the cache and is essentially serialized (i.e. the main start-up thread is used). The environmental information should only be used to optimize processing. For instance, when cache monitoring is enabled, the variable "pfc.gStream*" is defined and is a pointer to a gStream object that can be used to report statistical information to a monitoring collector.
- Parameters
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theEnv | - Reference to environmental information. |
Reimplemented in XrdFileCache::Cache.
◆ LocalFilePath()
virtual int XrdOucCache2::LocalFilePath |
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const char * |
url, |
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char * |
buff = 0 , |
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int |
blen = 0 , |
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LFP_Reason |
why = ForAccess , |
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bool |
forall = false |
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) |
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inlinevirtual |
◆ Prepare()
virtual int XrdOucCache2::Prepare |
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const char * |
url, |
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int |
oflags, |
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mode_t |
mode |
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) |
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inlinevirtual |
Prepare the cache for a file open request. This method is called prior to actually opening a file. This method is meant to allow defering an open request or implementing the full I/O stack in the cache layer.
- Parameters
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url | - Pointer to the url about to be opened. |
oflags | - Standard Unix open flags (see open(2)). |
mode | - Standard mode flags if file is being created. |
- Returns
- <0 Error has occurred, return value is -errno; fail open request. The error code -EUSERS may be returned to trigger overload recovery as specified by the xrootd.fsoverload directive. No other method should return this error code. =0 Continue with open() request. >0 Defer open but treat the file as actually being open. Use the XrdOucCacheIO2::Open() method to open the file at a later time.
Reimplemented in XrdFileCache::Cache.
◆ Stat()
virtual int XrdOucCache2::Stat |
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const char * |
url, |
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struct stat & |
sbuff |
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) |
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inlinevirtual |
Perform a stat() operation (defaults to passthrough).
- Parameters
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url | pointer to the url whose stat information is wanted. |
sbuff | reference to the stat buffer to be filled in. Only fields st_size, st_blocks, st_mtime (st_atime and st_ctime may be set to st_mtime), st_ino, and st_mode need to be set. All other fields are preset and should not be changed. |
- Returns
- <0 - Stat failed, value is -errno. =0 - Stat succeeded, sbuff holds stat information. >0 - Stat could not be done, forward operation to next level.
Reimplemented in XrdFileCache::Cache.
The documentation for this class was generated from the following file: