Cache Unicode C Reference Documentation

Cache

Create/Dispose

HCkCacheW CkCacheW_Create(void);

Creates an instance of the HCkCacheW object and returns a handle (i.e. a "void *" pointer). The handle is passed in the 1st argument for the functions listed on this page.

void CkCacheW_Dispose(HCkCacheW handle);

Objects created by calling CkCacheW_Create must be freed by calling this method. A memory leak occurs if a handle is not disposed by calling this function. Also, any handle returned by a Chilkat "C" function must also be freed by the application by calling the appropriate Dispose method, such as CkCacheW_Dispose.

Properties

void CkCacheW_getDebugLogFilePath(HCkCacheW cHandle, HCkString retval);

void CkCacheW_putDebugLogFilePath(HCkCacheW cHandle, const wchar_t *newVal);

const wchar_t *CkCacheW_debugLogFilePath(HCkCacheW cHandle);

If set to a file path, causes each Chilkat method or property call to automatically append it's LastErrorText to the specified log file. The information is appended such that if a hang or crash occurs, it is possible to see the context in which the problem occurred, as well as a history of all Chilkat calls up to the point of the problem. The VerboseLogging property can be set to provide more detailed information.

This property is typically used for debugging the rare cases where a Chilkat method call hangs or generates an exception that halts program execution (i.e. crashes). A hang or crash should generally never happen. The typical causes of a hang are:

  1. a timeout related property was set to 0 to explicitly indicate that an infinite timeout is desired,
  2. the hang is actually a hang within an event callback (i.e. it is a hang within the application code), or
  3. there is an internal problem (bug) in the Chilkat code that causes the hang.

void CkCacheW_getLastErrorHtml(HCkCacheW cHandle, HCkString retval);

const wchar_t *CkCacheW_lastErrorHtml(HCkCacheW cHandle);

Provides information in HTML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

void CkCacheW_getLastErrorText(HCkCacheW cHandle, HCkString retval);

const wchar_t *CkCacheW_lastErrorText(HCkCacheW cHandle);

Provides information in plain-text format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

Concept of LastErrorText

LastErrorText Standard Information

void CkCacheW_getLastErrorXml(HCkCacheW cHandle, HCkString retval);

const wchar_t *CkCacheW_lastErrorXml(HCkCacheW cHandle);

Provides information in XML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

void CkCacheW_getLastEtagFetched(HCkCacheW cHandle, HCkString retval);

const wchar_t *CkCacheW_lastEtagFetched(HCkCacheW cHandle);

The ETag of the last item fetched from cache.

SYSTEMTIME * CkCacheW_getLastExpirationFetched(HCkCacheW cHandle);

This property is deprecated. It will be removed in a future version.

Expiration date/time of the last item fetched from cache.

void CkCacheW_getLastExpirationFetchedStr(HCkCacheW cHandle, HCkString retval);

const wchar_t *CkCacheW_lastExpirationFetchedStr(HCkCacheW cHandle);

Expiration date/time of the last item fetched from cache in RFC822 string format.

BOOL CkCacheW_getLastHitExpired(HCkCacheW cHandle);

TRUE if the LastExpirationFetched is before the current date/time. Otherwise FALSE.

void CkCacheW_getLastKeyFetched(HCkCacheW cHandle, HCkString retval);

const wchar_t *CkCacheW_lastKeyFetched(HCkCacheW cHandle);

The key of the last item fetched from cache. (For web pages, the key is typically the canonicalized URL. Otherwise, the key is a unique identifer used to access the cached item.)

BOOL CkCacheW_getLastMethodSuccess(HCkCacheW cHandle);

void CkCacheW_putLastMethodSuccess(HCkCacheW cHandle, BOOL newVal);

Introduced in version 9.5.0.52

Indicate whether the last method call succeeded or failed. A value of TRUE indicates success, a value of FALSE indicates failure. This property is automatically set for method calls. It is not modified by property accesses. The property is automatically set to indicate success for the following types of method calls:

  • Any method that returns a string.
  • Any method returning a Chilkat object, binary bytes, or a date/time.
  • Any method returning a standard boolean status value where success = TRUE and failure = FALSE.
  • Any method returning an integer where failure is defined by a return value less than zero.

Note: Methods that do not fit the above requirements will always set this property equal to TRUE. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.

int CkCacheW_getLevel(HCkCacheW cHandle);

void CkCacheW_putLevel(HCkCacheW cHandle, int newVal);

The number of directory levels in the cache. Possible values are:

0: All cache files are in a single directory (the cache root).

1: Cache files are located in 256 sub-directories numbered 0 .. 255 directly under the cache root.

2: There are two levels of sub-directories under the cache root. The 1st level has 256 sub-directories numbered 0 .. 255 directly under the cache root. The 2nd level allows for up to 256 sub-directories (0..255) under each level-1 directory. Cache files are stored in the leaf directories.

int CkCacheW_getNumRoots(HCkCacheW cHandle);

The number of root directories composing the cache. A typical multi-root cache would place each root on a separate hard drive.

BOOL CkCacheW_getVerboseLogging(HCkCacheW cHandle);

void CkCacheW_putVerboseLogging(HCkCacheW cHandle, BOOL newVal);

If set to TRUE, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is FALSE. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

void CkCacheW_getVersion(HCkCacheW cHandle, HCkString retval);

const wchar_t *CkCacheW_version(HCkCacheW cHandle);

Version of the component/library, such as "9.5.0.63"

Methods

void CkCacheW_AddRoot(HCkCacheW cHandle, const wchar_t *path);

Must be called once for each cache root. For example, if the cache is spread across D:\cacheRoot, E:\cacheRoot, and F:\cacheRoot, an application would setup the cache object by calling AddRoot three times -- once with "D:\cacheRoot", once with "E:\cacheRoot", and once with "F:\cacheRoot".

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int CkCacheW_DeleteAll(HCkCacheW cHandle);

Deletes all items in the cache. This method completely clears the cache. All files in the cache are deleted. (If the cache is multi-level, existing sub-directories are not deleted.)

Returns the number of items (i.e. cache files) deleted.

int CkCacheW_DeleteAllExpired(HCkCacheW cHandle);

Deletes all expired items from the cache.

Returns the number of items (i.e. cache files) deleted.

BOOL CkCacheW_DeleteFromCache(HCkCacheW cHandle, const wchar_t *key);

Deletes a single item from the disk cache. Returns FALSE if the item exists in cache but could not be deleted. Otherwise returns TRUE.

Returns TRUE for success, FALSE for failure.

int CkCacheW_DeleteOlder(HCkCacheW cHandle, SYSTEMTIME * dateTime);

This method is deprecated. It will be removed in a future version.

Deletes all items older than a specified date/time.

Returns the number of items (i.e. cache files) deleted. Returns -1 on error.

int CkCacheW_DeleteOlderDt(HCkCacheW cHandle, HCkDateTimeW dateTime);

The same as DeleteOlder, except the dateTime is passed as a CkDateTime.

int CkCacheW_DeleteOlderStr(HCkCacheW cHandle, const wchar_t *dateTimeStr);

The same as DeleteOlder, except the dateTimeStr is passed as a date/time in RFC822 format.

BOOL CkCacheW_FetchFromCache(HCkCacheW cHandle, const wchar_t *key, const unsigned char * outBytes);

Fetches an item from cache.

The key may be any length and may include any characters. It should uniquely identify the cached item. (No two items in the cache should have the same key.)

Returns TRUE for success, FALSE for failure.

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BOOL CkCacheW_FetchText(HCkCacheW cHandle, const wchar_t *key, const wchar_t *outStr);

const wchar_t *CkCacheW_fetchText(HCkCacheW cHandle, const wchar_t *key);

Fetches a text item from the cache and returns it's text content.

The key may be any length and may include any characters. It should uniquely identify the cached item. (No two items in the cache should have the same key.)

Returns TRUE for success, FALSE for failure.

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BOOL CkCacheW_GetEtag(HCkCacheW cHandle, const wchar_t *key, const wchar_t *outStr);

const wchar_t *CkCacheW_getEtag(HCkCacheW cHandle, const wchar_t *key);

Returns the eTag for an item in the cache.

Returns TRUE for success, FALSE for failure.

BOOL CkCacheW_GetExpiration(HCkCacheW cHandle, const wchar_t *key, SYSTEMTIME * outSysTime);

This method is deprecated. It will be removed in a future version.

Returns the expire date/time for an item in the cache.

Returns TRUE for success, FALSE for failure.

HCkDateTimeW CkCacheW_GetExpirationDt(HCkCacheW cHandle, const wchar_t *key);

Returns the expiration date/time for an item in the cache as a CkDateTime object.

Returns NULL on failure

BOOL CkCacheW_GetExpirationStr(HCkCacheW cHandle, const wchar_t *url, const wchar_t *outStr);

const wchar_t *CkCacheW_getExpirationStr(HCkCacheW cHandle, const wchar_t *url);

Returns the expiration date/time for an item in the cache in RFC822 string format.

Returns TRUE for success, FALSE for failure.

BOOL CkCacheW_GetFilename(HCkCacheW cHandle, const wchar_t *key, const wchar_t *outStr);

const wchar_t *CkCacheW_getFilename(HCkCacheW cHandle, const wchar_t *key);

Returns the absolute file path of the cache file associated with the key.

Returns TRUE for success, FALSE for failure.

BOOL CkCacheW_GetRoot(HCkCacheW cHandle, int index, const wchar_t *outStr);

const wchar_t *CkCacheW_getRoot(HCkCacheW cHandle, int index);

Returns the directory path of the Nth cache root. (Indexing begins at 0.)

Returns TRUE for success, FALSE for failure.

BOOL CkCacheW_IsCached(HCkCacheW cHandle, const wchar_t *key);

Returns TRUE if the item is found in the cache, otherwise returns FALSE.

BOOL CkCacheW_SaveLastError(HCkCacheW cHandle, const wchar_t *path);

Saves the last-error information (the contents of LastErrorXml) to an XML formatted file.

Returns TRUE for success, FALSE for failure.

BOOL CkCacheW_SaveText(HCkCacheW cHandle, const wchar_t *key, SYSTEMTIME * expireDateTime, const wchar_t *eTag, const wchar_t *itemTextData);

This method is deprecated. It will be removed in a future version.

Inserts or replaces an text item in the cache. The eTag is optional and may be set to a zero-length string. Applications may use it as a place to save additional information about the cached item. The key may be any length and may include any characters. It should uniquely identify the cached item. (No two items in the cache should have the same key.)

Returns TRUE for success, FALSE for failure.

BOOL CkCacheW_SaveTextDt(HCkCacheW cHandle, const wchar_t *key, HCkDateTimeW expireDateTime, const wchar_t *eTag, const wchar_t *itemTextData);

The same as SaveText, except the expire date/time is passed as a CkDateTime object.

Returns TRUE for success, FALSE for failure.

BOOL CkCacheW_SaveTextNoExpire(HCkCacheW cHandle, const wchar_t *key, const wchar_t *eTag, const wchar_t *itemTextData);

Inserts or replaces an text item in the cache with no expiration date/time. The eTag is optional and may be set to a zero-length string. Applications may use it as a place to save additional information about the cached item.

Returns TRUE for success, FALSE for failure.

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BOOL CkCacheW_SaveTextStr(HCkCacheW cHandle, const wchar_t *key, const wchar_t *expireDateTime, const wchar_t *eTag, const wchar_t *itemTextData);

The same as SaveText, except the expire date/time is passed as a string in RFC822 format.

Returns TRUE for success, FALSE for failure.

BOOL CkCacheW_SaveToCache(HCkCacheW cHandle, const wchar_t *key, SYSTEMTIME * expireDateTime, const wchar_t *eTag, const unsigned char * itemData);

This method is deprecated. It will be removed in a future version.

Inserts or replaces an item in the cache. The eTag is optional and may be set to a zero-length string. Applications may use it as a place to save additional information about the cached item. (The Chilkat HTTP component, when caching a page, writes the eTag (entity-tag) from the HTTP response header to this field.)

The key may be any length and may include any characters. It should uniquely identify the cached item. (No two items in the cache should have the same key.)

Returns TRUE for success, FALSE for failure.

BOOL CkCacheW_SaveToCacheDt(HCkCacheW cHandle, const wchar_t *key, HCkDateTimeW expireDateTime, const wchar_t *eTag, const unsigned char * itemData);

The same as SaveToCache, except the expire date/time is passed as a CkDateTime object.

Returns TRUE for success, FALSE for failure.

BOOL CkCacheW_SaveToCacheNoExpire(HCkCacheW cHandle, const wchar_t *key, const wchar_t *eTag, const unsigned char * itemData);

Inserts or replaces an item in the cache. The cached item will have no expiration. The eTag is optional and may be set to a zero-length string. Applications may use it as a place to save additional information about the cached item.

Returns TRUE for success, FALSE for failure.

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BOOL CkCacheW_SaveToCacheStr(HCkCacheW cHandle, const wchar_t *key, const wchar_t *expireDateTime, const wchar_t *eTag, const unsigned char * itemData);

The same as SaveToCache, except the expire date/time is passed in RFC822 string format.

Returns TRUE for success, FALSE for failure.

BOOL CkCacheW_UpdateExpiration(HCkCacheW cHandle, const wchar_t *key, SYSTEMTIME * expireDateTime);

This method is deprecated. It will be removed in a future version.

Updates the expire date/time for a cached item.

Returns TRUE for success, FALSE for failure.

BOOL CkCacheW_UpdateExpirationDt(HCkCacheW cHandle, const wchar_t *key, HCkDateTimeW expireDateTime);

The same as UpdateExpiration, except the expireDateTime is passed as a CkDateTime.

Returns TRUE for success, FALSE for failure.

BOOL CkCacheW_UpdateExpirationStr(HCkCacheW cHandle, const wchar_t *key, const wchar_t *expireDateTime);

The same as UpdateExpiration, except the expireDateTime is passed in RFC822 string format.

Returns TRUE for success, FALSE for failure.