.TH "kdbopmphm.h" 3elektra "Fri Aug 4 2023" "Version 0.11.0" "Elektra" \" -*- nroff -*-
.ad l
.nh
.SH NAME
kdbopmphm.h \- Defines for the Order Preserving Minimal Perfect Hash Map\&.  

.SH SYNOPSIS
.br
.PP
\fC#include <stdint\&.h>\fP
.br
\fC#include <stdlib\&.h>\fP
.br
\fC#include <kdbtypes\&.h>\fP
.br

.SS "Classes"

.in +1c
.ti -1c
.RI "struct \fBOpmphmEdge\fP"
.br
.RI "Order Preserving Minimal Perfect Hash Map\&. "
.ti -1c
.RI "struct \fBOpmphm\fP"
.br
.RI "The opmphm\&. "
.in -1c
.SS "Macros"

.in +1c
.ti -1c
.RI "#define \fBOPMPHM_HASHFUNCTION_ROT\fP(x,  k)   (((x) << (k)) | ((x) >> (32 \- (k))))"
.br
.RI "Hash function By Bob Jenkins, May 2006 http://burtleburtle.net/bob/c/lookup3.c\&. "
.in -1c
.SS "Typedefs"

.in +1c
.ti -1c
.RI "typedef const char *(* \fBopmphmGetName\fP) (void *)"
.br
.RI "Only needed for Initialisation\&. "
.in -1c
.SS "Enumerations"

.in +1c
.ti -1c
.RI "enum \fBopmphmflag_t\fP { \fBOPMPHM_FLAG_MMAP_STRUCT\fP = 1, \fBOPMPHM_FLAG_MMAP_HASHFUNCTIONSEEDS\fP = 1 << 2, \fBOPMPHM_FLAG_MMAP_GRAPH\fP = 1 << 3 }"
.br
.RI "\fBOpmphm\fP Flags\&. "
.in -1c
.SS "Functions"

.in +1c
.ti -1c
.RI "double \fBopmphmMinC\fP (uint8_t r)"
.br
.RI "Functions providing \fCr\fP and \fCc\fP "
.ti -1c
.RI "uint8_t \fBopmphmOptR\fP (size_t n)"
.br
.RI "Provides the optimal \fCr\fP value for a given \fCn\fP "
.ti -1c
.RI "double \fBopmphmOptC\fP (size_t n)"
.br
.RI "Provides the optimal \fCc\fP value for a given \fCn\fP "
.ti -1c
.RI "OpmphmGraph * \fBopmphmGraphNew\fP (\fBOpmphm\fP *opmphm, uint8_t r, size_t n, double c)"
.br
.RI "Graph functions\&. "
.ti -1c
.RI "void \fBopmphmGraphClear\fP (const \fBOpmphm\fP *opmphm, OpmphmGraph *graph)"
.br
.RI "Clears the OpmphmGraph\&. "
.ti -1c
.RI "void \fBopmphmGraphDel\fP (OpmphmGraph *graph)"
.br
.RI "Deletes the OpmphmGraph\&. "
.ti -1c
.RI "int \fBopmphmMapping\fP (\fBOpmphm\fP *opmphm, OpmphmGraph *graph, OpmphmInit *init, size_t n)"
.br
.RI "Build functions\&. "
.ti -1c
.RI "int \fBopmphmAssignment\fP (\fBOpmphm\fP *opmphm, OpmphmGraph *graph, size_t n, int defaultOrder)"
.br
.RI "Assigns the vertices of the r-uniform r-partite hypergraph\&. "
.ti -1c
.RI "size_t \fBopmphmLookup\fP (\fBOpmphm\fP *opmphm, size_t n, const void *name)"
.br
.RI "Lookup functions\&. "
.ti -1c
.RI "\fBOpmphm\fP * \fBopmphmNew\fP (void)"
.br
.RI "Basic functions\&. "
.ti -1c
.RI "void \fBopmphmDel\fP (\fBOpmphm\fP *opmphm)"
.br
.RI "Deletes the OPMPHM\&. "
.ti -1c
.RI "int \fBopmphmIsBuild\fP (const \fBOpmphm\fP *opmphm)"
.br
.RI "OPMPHM is build\&. "
.ti -1c
.RI "int \fBopmphmCopy\fP (\fBOpmphm\fP *dest, const \fBOpmphm\fP *source)"
.br
.RI "Copies OPMPHM from source to destination\&. "
.ti -1c
.RI "void \fBopmphmClear\fP (\fBOpmphm\fP *opmphm)"
.br
.RI "Clears the OPMPHM\&. "
.ti -1c
.RI "uint32_t \fBopmphmHashfunction\fP (const void *key, size_t length, uint32_t initval)"
.br
.RI "Hash function By Bob Jenkins, May 2006 http://burtleburtle.net/bob/c/lookup3.c Original name: hashlitte\&. "
.in -1c
.SH "Detailed Description"
.PP 
Defines for the Order Preserving Minimal Perfect Hash Map\&. 


.PP
\fBCopyright\fP
.RS 4
BSD License (see doc/COPYING or https://www.libelektra.org) 
.RE
.PP

.SH "Enumeration Type Documentation"
.PP 
.SS "enum \fBopmphmflag_t\fP"

.PP
\fBOpmphm\fP Flags\&. 
.PP
\fBEnumerator\fP
.in +1c
.TP
\fB\fIOPMPHM_FLAG_MMAP_STRUCT \fP\fP
\fBOpmphm\fP struct lies inside a mmap region\&. This flag is set for \fBOpmphm\fP structs inside a mapped region\&. It prevents erroneous free() calls on these \fBOpmphm\fP structs\&. 
.TP
\fB\fIOPMPHM_FLAG_MMAP_HASHFUNCTIONSEEDS \fP\fP
\fBOpmphm\fP hashFunctionSeeds lies inside a mmap region\&. This flag is set for \fBOpmphm\fP hashFunctionSeeds inside a mapped region\&. It prevents erroneous free() calls on these hashFunctionSeeds\&. 
.TP
\fB\fIOPMPHM_FLAG_MMAP_GRAPH \fP\fP
\fBOpmphm\fP graph lies inside a mmap region\&. This flag is set for \fBOpmphm\fP graphs inside a mapped region\&. It prevents erroneous free() calls on these graphs\&. 
.SH "Function Documentation"
.PP 
.SS "int opmphmAssignment (\fBOpmphm\fP * opmphm, OpmphmGraph * graph, size_t n, int defaultOrder)"

.PP
Assigns the vertices of the r-uniform r-partite hypergraph\&. Allocs the memory for the final OPMPHM \fCOpmphm->graph\fP\&. Uses the remove sequence \fCOpmphmGraph->removeSequence\fP, generated during cycle check, to assign each vertex\&. Either with \fCOpmphmEdge->order\fP or the default order, default is the order of \fCOpmphmInit->data\fP\&.
.PP
\fBParameters\fP
.RS 4
\fIopmphm\fP the OPMPHM 
.br
\fIgraph\fP the OpmphmGraph 
.br
\fIn\fP the number of elements 
.br
\fIdefaultOrder\fP boolean flag
.RE
.PP
\fBReturn values\fP
.RS 4
\fI0\fP on success 
.br
\fI-1\fP on memory error 
.RE
.PP

.SS "void opmphmClear (\fBOpmphm\fP * opmphm)"

.PP
Clears the OPMPHM\&. The OPMPHM must be successfully created with \fCopmphmNew ()\fP\&. Clears and frees all internal memory of \fBOpmphm\fP, but not \fCOpmphm->hashFunctionSeeds\fP and the \fBOpmphm\fP instance\&.
.PP
\fBParameters\fP
.RS 4
\fIopmphm\fP the OPMPHM 
.RE
.PP

.SS "int opmphmCopy (\fBOpmphm\fP * dest, const \fBOpmphm\fP * source)"

.PP
Copies OPMPHM from source to destination\&. Clears the dest and copies memory and values from source\&.
.PP
\fBParameters\fP
.RS 4
\fIdest\fP the OPMPHM destination 
.br
\fIsource\fP the OPMPHM source
.RE
.PP
\fBReturn values\fP
.RS 4
\fI0\fP on success 
.br
\fI-1\fP on memory error 
.RE
.PP

.SS "void opmphmDel (\fBOpmphm\fP * opmphm)"

.PP
Deletes the OPMPHM\&. Clears and frees all memory in \fBOpmphm\fP\&.
.PP
\fBParameters\fP
.RS 4
\fIopmphm\fP the OPMPHM 
.RE
.PP

.SS "void opmphmGraphClear (const \fBOpmphm\fP * opmphm, OpmphmGraph * graph)"

.PP
Clears the OpmphmGraph\&. Sets all vertices to 0\&.
.PP
\fBParameters\fP
.RS 4
\fIopmphm\fP the OPMPHM 
.br
\fIgraph\fP the OpmphmGraph 
.RE
.PP

.SS "void opmphmGraphDel (OpmphmGraph * graph)"

.PP
Deletes the OpmphmGraph\&. 
.PP
\fBParameters\fP
.RS 4
\fIgraph\fP the OpmphmGraph 
.RE
.PP

.SS "OpmphmGraph* opmphmGraphNew (\fBOpmphm\fP * opmphm, uint8_t r, size_t n, double c)"

.PP
Graph functions\&. Graph functions\&.
.PP
The OpmphmGraph represents a r-uniform r-partite hypergraph\&. Lazy initializes the \fCopmphm->hashFunctionSeeds\fP with r\&. Calculates also the size of one partition in the r-uniform r-partite hypergraph and stores it in \fCopmphm->componentSize\fP\&. Allocates all memory for the OpmphmGraph\&.
.PP
\fBParameters\fP
.RS 4
\fIopmphm\fP the OPMPHM 
.br
\fIr\fP the rUniPar 
.br
\fIn\fP the number of elements 
.br
\fIc\fP space influencing parameter
.RE
.PP
\fBReturn values\fP
.RS 4
\fIOpmphmGraph\fP * success 
.br
\fINULL\fP memory error 
.RE
.PP

.SS "int opmphmIsBuild (const \fBOpmphm\fP * opmphm)"

.PP
OPMPHM is build\&. 
.PP
\fBParameters\fP
.RS 4
\fIopmphm\fP the OPMPHM
.RE
.PP
\fBReturn values\fP
.RS 4
\fI0\fP on false 
.br
\fI-1\fP on true or NULL 
.RE
.PP

.SS "size_t opmphmLookup (\fBOpmphm\fP * opmphm, size_t n, const void * name)"

.PP
Lookup functions\&. Lookup functions\&.
.PP
\fBParameters\fP
.RS 4
\fIopmphm\fP the OPMPHM 
.br
\fIn\fP the number of elements 
.br
\fIname\fP the name of the element
.RE
.PP
\fBReturn values\fP
.RS 4
\fIsize_t\fP the order of the element\&. 
.RE
.PP

.SS "int opmphmMapping (\fBOpmphm\fP * opmphm, OpmphmGraph * graph, OpmphmInit * init, size_t n)"

.PP
Build functions\&. Build functions\&.
.PP
Sets the seeds for the opmphmHashfunctions, \fCOpmphmInit->initSeed\fP will be changed\&. Inserts each element as edge in the r-uniform r-partite hypergraph and checks if the graph contains a cycle\&. If there are cycles the \fCgraph\fP will be cleaned
.PP
\fBParameters\fP
.RS 4
\fIopmphm\fP the OPMPHM 
.br
\fIgraph\fP the OpmphmGraph 
.br
\fIinit\fP the OpmphmInit 
.br
\fIn\fP the number of elements
.RE
.PP
\fBReturn values\fP
.RS 4
\fI0\fP on success 
.br
\fI-1\fP mapping not possible 
.RE
.PP

.SS "double opmphmMinC (uint8_t r)"

.PP
Functions providing \fCr\fP and \fCc\fP Functions providing \fCr\fP and \fCc\fP
.PP
This minimal values come from Fabiano Cupertino Botelho, Near-Optimal Space Perfect Hashing Algorithms, 2008\&.
.PP
\fBParameters\fP
.RS 4
\fIr\fP the rUniPar
.RE
.PP
\fBReturn values\fP
.RS 4
\fIc\fP the minimal c value 
.RE
.PP

.SS "\fBOpmphm\fP* opmphmNew (void)"

.PP
Basic functions\&. Basic functions\&.
.PP
\fBReturn values\fP
.RS 4
\fI\fBOpmphm\fP\fP * success 
.br
\fINULL\fP memory error 
.RE
.PP

.SS "double opmphmOptC (size_t n)"

.PP
Provides the optimal \fCc\fP value for a given \fCn\fP This is a heuristic, the return values follow from the mapping benchmark\&.
.PP
\fBParameters\fP
.RS 4
\fIn\fP the number of elements to hash
.RE
.PP
\fBReturn values\fP
.RS 4
\fIc\fP the optimal \fCc\fP value 
.RE
.PP

.SS "uint8_t opmphmOptR (size_t n)"

.PP
Provides the optimal \fCr\fP value for a given \fCn\fP This is a heuristic, the return values follow from the mapping benchmark\&.
.PP
\fBParameters\fP
.RS 4
\fIn\fP the number of elements to hash
.RE
.PP
\fBReturn values\fP
.RS 4
\fIr\fP the optimal rUniPar 
.RE
.PP

.SH "Author"
.PP 
Generated automatically by Doxygen for Elektra from the source code\&.