NAME
JudyL functions - C library for creating and accessing a dynamic array
of words, using any value of a word as an index
SYNOPSIS
PPvoid_t JudyLIns( PPvoid_t PPJLArray, Word_t Index, PJError_t PJError);
int JudyLDel( PPvoid_t PPJLArray, Word_t Index, PJError_t PJError);
PPvoid_t JudyLGet( Pcvoid_t PJLArray, Word_t Index, PJError_t PJError);
Word_t JudyLCount( Pcvoid_t PJLArray, Word_t Index1, Word_t Index2, PJError_t PJError);
PPvoid_t JudyLByCount( Pcvoid_t PJLArray, Word_t Nth, Word_t * PIndex, PJError_t PJError);
Word_t JudyLFreeArray( PPvoid_t PPJLArray, PJError_t PJError);
Word_t JudyLMemUsed( Pcvoid_t PJLArray);
PPvoid_t JudyLFirst( Pcvoid_t PJLArray, Word_t * PIndex, PJError_t PJError);
PPvoid_t JudyLNext( Pcvoid_t PJLArray, Word_t * PIndex, PJError_t PJError);
PPvoid_t JudyLLast( Pcvoid_t PJLArray, Word_t * PIndex, PJError_t PJError);
PPvoid_t JudyLPrev( Pcvoid_t PJLArray, Word_t * PIndex, PJError_t PJError);
int JudyLFirstEmpty(Pcvoid_t PJLArray, Word_t * PIndex, PJError_t PJError);
int JudyLNextEmpty( Pcvoid_t PJLArray, Word_t * PIndex, PJError_t PJError);
int JudyLLastEmpty( Pcvoid_t PJLArray, Word_t * PIndex, PJError_t PJError);
int JudyLPrevEmpty( Pcvoid_t PJLArray, Word_t * PIndex, PJError_t PJError);
DESCRIPTION
A macro equivalent exists for each function call. Because the macro
forms are sometimes faster and have a simpler error handling interface
than the equivalent functions, they are the preferred way of calling
the JudyL functions. See JudyL(3) for more information. The function
call definitions are included here for completeness.
One of the difficulties in using the JudyL function calls lies in
determining whether to pass a pointer or the address of a pointer.
Since the functions that modify the JudyL array must also modify the
pointer to the JudyL array, you must pass the address of the pointer
rather than the pointer itself. This often leads to hard-to-debug
programmatic errors. In practice, the macros allow the compiler to
catch programming errors when pointers instead of addresses of pointers
are passed.
The JudyL function calls have an additional parameter beyond those
specified in the macro calls. This parameter is either a pointer to an
error structure, or NULL (in which case the detailed error information
is not returned).
In the following descriptions, the functions are described in terms of
how the macros use them (only in the case of #define JUDYERROR_NOTEST
1). This is the suggested use of the macros after your program has
been fully debugged. When the JUDYERROR_NOTEST macro is not specified,
an error structure is declared to store error information returned from
the JudyL functions when an error occurs.
Notice the placement of the & in the different functions.
JudyLIns(&PJLArray, Index, &JError)
#define JLI(PValue, PJLArray, Index) \
PValue = JudyLIns(&PJLArray, Index, PJE0)
JudyLDel(&PJLArray, Index, &JError)
#define JLD(Rc_int, PJLArray, Index) \
Rc_int = JudyLDel(&PJLArray, Index, PJE0)
JudyLGet(PJLArray, Index, &JError)
#define JLG(PValue, PJLArray, Index) \
PValue = JudyLGet(PJLArray, Index, PJE0)
JudyLCount(PJLArray, Index1, Index2, &JError)
#define JLC(Rc_word, PJLArray, Index1, Index2) \
Rc_word = JudyLCount(PJLArray, Index1, Index2, PJE0)
JudyLByCount(PJLArray, Nth, &Index, &JError)
#define JLBC(PValue, PJLArray, Nth, Index) \
PValue = JudyLByCount(PJLArray, Nth, &Index, PJE0)
JudyLFreeArray(&PJLArray, &JError)
#define JLFA(Rc_word, PJLArray) \
Rc_word = JudyLFreeArray(&PJLArray, PJE0)
JudyLMemUsed(PJLArray)
#define JLMU(Rc_word, PJLArray) \
Rc_word = JudyLMemUsed(PJLArray)
JudyLFirst(PJLArray, &Index, &JError)
#define JLF(PValue, PJLArray, Index) \
PValue = JudyLFirst(PJLArray, &Index, PJEO)
JudyLNext(PJLArray, &Index, &JError)
#define JLN(PValue, PJLArray, Index) \
PValue = JudyLNext(PJLArray, &Index, PJEO)
JudyLLast(PJLArray, &Index, &JError)
#define JLL(PValue, PJLArray, Index) \
PValue = JudyLLast(PJLArray, &Index, PJEO)
JudyLPrev(PJLArray, &Index, &JError)
#define JLP(PValue, PJLArray, Index) \
PValue = JudyLPrev(PJLArray, &Index, PJEO)
JudyLFirstEmpty(PJLArray, &Index, &JError)
#define JLFE(Rc_int, PJLArray, Index) \
Rc_int = JudyLFirstEmpty(PJLArray, &Index, PJEO)
JudyLNextEmpty(PJLArray, &Index, &JError)
#define JLNE(Rc_int, PJLArray, Index) \
Rc_int = JudyLNextEmpty(PJLArray, &Index, PJEO)
JudyLLastEmpty(PJLArray, &Index, &JError)
#define JLLE(Rc_int, PJLArray, Index) \
Rc_int = JudyLLastEmpty(PJLArray, &Index, PJEO)
JudyLPrevEmpty(PJLArray, &Index, &JError)
#define JLPE(Rc_int, PJLArray, Index) \
Rc_int = JudyLPrevEmpty(PJLArray, &Index, PJEO)
Definitions for all the Judy functions, the types Pvoid_t, Pcvoid_t,
PPvoid_t, Word_t, JError_t, and PJError_t, the constants NULL,
JU_ERRNO_*, JERR, PPJERR, and PJE0, are provided in the Judy.h header
file (/usr/include/Judy.h). Note: Callers should define JudyL arrays
as type Pvoid_t, which can be passed by value to functions that take
Pcvoid_t (constant Pvoid_t), and also by address to functions that take
PPvoid_t.
The return type from most JudyL functions is PPvoid_t so that the
values stored in the array can be pointers to other objects, which is a
typical usage, or cast to a Word_t * when a pointer to a Value is
required instead of a pointer to a pointer.
AUTHOR
Judy was invented by Doug Baskins and implemented by Hewlett-Packard.
SEE ALSO
Judy(3), Judy1(3), JudyL(3), JudySL(3), JudyHS(3),
malloc(),
the Judy website, http://judy.sourceforge.net, for more information and
Application Notes.
JudyL_funcs(3)