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hash

hash - Chained hash tables

This module implements the hash table support used in various places in the library.

Author(s): Bjorn Reese <bjorn.reese@systematic.dk>

Synopsis

#define XML_CAST_FPTR(fptr);
typedef struct _xmlHashTable xmlHashTable;
typedef xmlHashTable * xmlHashTablePtr;
void	xmlHashScanFull			(xmlHashTablePtr table, 
					 xmlHashScannerFull f, 
					 void * data);
void	xmlHashScan			(xmlHashTablePtr table, 
					 xmlHashScanner f, 
					 void * data);
typedef void xmlHashScannerFull		(void * payload, 
					 void * data, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 const xmlChar * name3);
xmlHashTablePtr	xmlHashCreateDict	(int size, 
					 xmlDictPtr dict);
int	xmlHashAddEntry			(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 void * userdata);
int	xmlHashUpdateEntry		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 void * userdata, 
					 xmlHashDeallocator f);
void *	xmlHashQLookup3			(xmlHashTablePtr table, 
					 const xmlChar * prefix, 
					 const xmlChar * name, 
					 const xmlChar * prefix2, 
					 const xmlChar * name2, 
					 const xmlChar * prefix3, 
					 const xmlChar * name3);
void *	xmlHashQLookup2			(xmlHashTablePtr table, 
					 const xmlChar * prefix, 
					 const xmlChar * name, 
					 const xmlChar * prefix2, 
					 const xmlChar * name2);
void	xmlHashScan3			(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 const xmlChar * name3, 
					 xmlHashScanner f, 
					 void * data);
typedef void xmlHashScanner			(void * payload, 
					 void * data, 
					 xmlChar * name);
typedef void xmlHashDeallocator		(void * payload, 
					 xmlChar * name);
xmlHashTablePtr	xmlHashCreate		(int size);
void	xmlHashFree			(xmlHashTablePtr table, 
					 xmlHashDeallocator f);
void *	xmlHashLookup			(xmlHashTablePtr table, 
					 const xmlChar * name);
void *	xmlHashQLookup			(xmlHashTablePtr table, 
					 const xmlChar * prefix, 
					 const xmlChar * name);
int	xmlHashUpdateEntry2		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 void * userdata, 
					 xmlHashDeallocator f);
int	xmlHashRemoveEntry2		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 xmlHashDeallocator f);
int	xmlHashRemoveEntry3		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 const xmlChar * name3, 
					 xmlHashDeallocator f);
xmlHashTablePtr	xmlHashCopy		(xmlHashTablePtr table, 
					 xmlHashCopier f);
void	xmlHashScanFull3		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 const xmlChar * name3, 
					 xmlHashScannerFull f, 
					 void * data);
int	xmlHashUpdateEntry3		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 const xmlChar * name3, 
					 void * userdata, 
					 xmlHashDeallocator f);
void *	xmlHashLookup3			(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 const xmlChar * name3);
void *	xmlHashLookup2			(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2);
int	xmlHashRemoveEntry		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 xmlHashDeallocator f);
typedef void * xmlHashCopier			(void * payload, 
					 xmlChar * name);
int	xmlHashAddEntry2		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 void * userdata);
int	xmlHashAddEntry3		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 const xmlChar * name3, 
					 void * userdata);
int	xmlHashSize			(xmlHashTablePtr table);

Description

Details

Macro XML_CAST_FPTR

#define XML_CAST_FPTR(fptr);

Macro to do a casting from an object pointer to a function pointer without encountering a warning from gcc #define XML_CAST_FPTR(fptr) (*(void **)(&fptr)) This macro violated ISO C aliasing rules (gcc4 on s390 broke) so it is disabled now

fptr:pointer to a function

Structure xmlHashTable

struct _xmlHashTable {
The content of this structure is not made public by the API.
} xmlHashTable;

Typedef xmlHashTablePtr

xmlHashTable * xmlHashTablePtr;

Function type xmlHashCopier

void *	xmlHashCopier			(void * payload, 
					 xmlChar * name)

Callback to copy data from a hash.

payload:the data in the hash
name:the name associated
Returns:a copy of the data or NULL in case of error.

Function type xmlHashDeallocator

void	xmlHashDeallocator		(void * payload, 
					 xmlChar * name)

Callback to free data from a hash.

payload:the data in the hash
name:the name associated

Function type xmlHashScanner

void	xmlHashScanner			(void * payload, 
					 void * data, 
					 xmlChar * name)

Callback when scanning data in a hash with the simple scanner.

payload:the data in the hash
data:extra scannner data
name:the name associated

Function type xmlHashScannerFull

void	xmlHashScannerFull		(void * payload, 
					 void * data, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 const xmlChar * name3)

Callback when scanning data in a hash with the full scanner.

payload:the data in the hash
data:extra scannner data
name:the name associated
name2:the second name associated
name3:the third name associated

xmlHashAddEntry ()

int	xmlHashAddEntry			(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 void * userdata)

Add the @userdata to the hash @table. This can later be retrieved by using the @name. Duplicate names generate errors.

table:the hash table
name:the name of the userdata
userdata:a pointer to the userdata
Returns:0 the addition succeeded and -1 in case of error.

xmlHashAddEntry2 ()

int	xmlHashAddEntry2		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 void * userdata)

Add the @userdata to the hash @table. This can later be retrieved by using the (@name, @name2) tuple. Duplicate tuples generate errors.

table:the hash table
name:the name of the userdata
name2:a second name of the userdata
userdata:a pointer to the userdata
Returns:0 the addition succeeded and -1 in case of error.

xmlHashAddEntry3 ()

int	xmlHashAddEntry3		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 const xmlChar * name3, 
					 void * userdata)

Add the @userdata to the hash @table. This can later be retrieved by using the tuple (@name, @name2, @name3). Duplicate entries generate errors.

table:the hash table
name:the name of the userdata
name2:a second name of the userdata
name3:a third name of the userdata
userdata:a pointer to the userdata
Returns:0 the addition succeeded and -1 in case of error.

xmlHashCopy ()

xmlHashTablePtr	xmlHashCopy		(xmlHashTablePtr table, 
					 xmlHashCopier f)

Scan the hash @table and applied @f to each value.

table:the hash table
f:the copier function for items in the hash
Returns:the new table or NULL in case of error.

xmlHashCreate ()

xmlHashTablePtr	xmlHashCreate		(int size)

Create a new xmlHashTablePtr.

size:the size of the hash table
Returns:the newly created object, or NULL if an error occured.

xmlHashCreateDict ()

xmlHashTablePtr	xmlHashCreateDict	(int size, 
					 xmlDictPtr dict)

Create a new xmlHashTablePtr which will use @dict as the internal dictionary

size:the size of the hash table
dict:a dictionary to use for the hash
Returns:the newly created object, or NULL if an error occured.

xmlHashFree ()

void	xmlHashFree			(xmlHashTablePtr table, 
					 xmlHashDeallocator f)

Free the hash @table and its contents. The userdata is deallocated with @f if provided.

table:the hash table
f:the deallocator function for items in the hash

xmlHashLookup ()

void *	xmlHashLookup			(xmlHashTablePtr table, 
					 const xmlChar * name)

Find the userdata specified by the @name.

table:the hash table
name:the name of the userdata
Returns:the pointer to the userdata

xmlHashLookup2 ()

void *	xmlHashLookup2			(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2)

Find the userdata specified by the (@name, @name2) tuple.

table:the hash table
name:the name of the userdata
name2:a second name of the userdata
Returns:the pointer to the userdata

xmlHashLookup3 ()

void *	xmlHashLookup3			(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 const xmlChar * name3)

Find the userdata specified by the (@name, @name2, @name3) tuple.

table:the hash table
name:the name of the userdata
name2:a second name of the userdata
name3:a third name of the userdata
Returns:the a pointer to the userdata

xmlHashQLookup ()

void *	xmlHashQLookup			(xmlHashTablePtr table, 
					 const xmlChar * prefix, 
					 const xmlChar * name)

Find the userdata specified by the QName @prefix:@name/@name.

table:the hash table
prefix:the prefix of the userdata
name:the name of the userdata
Returns:the pointer to the userdata

xmlHashQLookup2 ()

void *	xmlHashQLookup2			(xmlHashTablePtr table, 
					 const xmlChar * prefix, 
					 const xmlChar * name, 
					 const xmlChar * prefix2, 
					 const xmlChar * name2)

Find the userdata specified by the QNames tuple

table:the hash table
prefix:the prefix of the userdata
name:the name of the userdata
prefix2:the second prefix of the userdata
name2:a second name of the userdata
Returns:the pointer to the userdata

xmlHashQLookup3 ()

void *	xmlHashQLookup3			(xmlHashTablePtr table, 
					 const xmlChar * prefix, 
					 const xmlChar * name, 
					 const xmlChar * prefix2, 
					 const xmlChar * name2, 
					 const xmlChar * prefix3, 
					 const xmlChar * name3)

Find the userdata specified by the (@name, @name2, @name3) tuple.

table:the hash table
prefix:the prefix of the userdata
name:the name of the userdata
prefix2:the second prefix of the userdata
name2:a second name of the userdata
prefix3:the third prefix of the userdata
name3:a third name of the userdata
Returns:the a pointer to the userdata

xmlHashRemoveEntry ()

int	xmlHashRemoveEntry		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 xmlHashDeallocator f)

Find the userdata specified by the @name and remove it from the hash @table. Existing userdata for this tuple will be removed and freed with @f.

table:the hash table
name:the name of the userdata
f:the deallocator function for removed item (if any)
Returns:0 if the removal succeeded and -1 in case of error or not found.

xmlHashRemoveEntry2 ()

int	xmlHashRemoveEntry2		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 xmlHashDeallocator f)

Find the userdata specified by the (@name, @name2) tuple and remove it from the hash @table. Existing userdata for this tuple will be removed and freed with @f.

table:the hash table
name:the name of the userdata
name2:a second name of the userdata
f:the deallocator function for removed item (if any)
Returns:0 if the removal succeeded and -1 in case of error or not found.

xmlHashRemoveEntry3 ()

int	xmlHashRemoveEntry3		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 const xmlChar * name3, 
					 xmlHashDeallocator f)

Find the userdata specified by the (@name, @name2, @name3) tuple and remove it from the hash @table. Existing userdata for this tuple will be removed and freed with @f.

table:the hash table
name:the name of the userdata
name2:a second name of the userdata
name3:a third name of the userdata
f:the deallocator function for removed item (if any)
Returns:0 if the removal succeeded and -1 in case of error or not found.

xmlHashScan ()

void	xmlHashScan			(xmlHashTablePtr table, 
					 xmlHashScanner f, 
					 void * data)

Scan the hash @table and applied @f to each value.

table:the hash table
f:the scanner function for items in the hash
data:extra data passed to f

xmlHashScan3 ()

void	xmlHashScan3			(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 const xmlChar * name3, 
					 xmlHashScanner f, 
					 void * data)

Scan the hash @table and applied @f to each value matching (@name, @name2, @name3) tuple. If one of the names is null, the comparison is considered to match.

table:the hash table
name:the name of the userdata or NULL
name2:a second name of the userdata or NULL
name3:a third name of the userdata or NULL
f:the scanner function for items in the hash
data:extra data passed to f

xmlHashScanFull ()

void	xmlHashScanFull			(xmlHashTablePtr table, 
					 xmlHashScannerFull f, 
					 void * data)

Scan the hash @table and applied @f to each value.

table:the hash table
f:the scanner function for items in the hash
data:extra data passed to f

xmlHashScanFull3 ()

void	xmlHashScanFull3		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 const xmlChar * name3, 
					 xmlHashScannerFull f, 
					 void * data)

Scan the hash @table and applied @f to each value matching (@name, @name2, @name3) tuple. If one of the names is null, the comparison is considered to match.

table:the hash table
name:the name of the userdata or NULL
name2:a second name of the userdata or NULL
name3:a third name of the userdata or NULL
f:the scanner function for items in the hash
data:extra data passed to f

xmlHashSize ()

int	xmlHashSize			(xmlHashTablePtr table)

Query the number of elements installed in the hash @table.

table:the hash table
Returns:the number of elements in the hash table or -1 in case of error

xmlHashUpdateEntry ()

int	xmlHashUpdateEntry		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 void * userdata, 
					 xmlHashDeallocator f)

Add the @userdata to the hash @table. This can later be retrieved by using the @name. Existing entry for this @name will be removed and freed with @f if found.

table:the hash table
name:the name of the userdata
userdata:a pointer to the userdata
f:the deallocator function for replaced item (if any)
Returns:0 the addition succeeded and -1 in case of error.

xmlHashUpdateEntry2 ()

int	xmlHashUpdateEntry2		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 void * userdata, 
					 xmlHashDeallocator f)

Add the @userdata to the hash @table. This can later be retrieved by using the (@name, @name2) tuple. Existing entry for this tuple will be removed and freed with @f if found.

table:the hash table
name:the name of the userdata
name2:a second name of the userdata
userdata:a pointer to the userdata
f:the deallocator function for replaced item (if any)
Returns:0 the addition succeeded and -1 in case of error.

xmlHashUpdateEntry3 ()

int	xmlHashUpdateEntry3		(xmlHashTablePtr table, 
					 const xmlChar * name, 
					 const xmlChar * name2, 
					 const xmlChar * name3, 
					 void * userdata, 
					 xmlHashDeallocator f)

Add the @userdata to the hash @table. This can later be retrieved by using the tuple (@name, @name2, @name3). Existing entry for this tuple will be removed and freed with @f if found.

table:the hash table
name:the name of the userdata
name2:a second name of the userdata
name3:a third name of the userdata
userdata:a pointer to the userdata
f:the deallocator function for replaced item (if any)
Returns:0 the addition succeeded and -1 in case of error.