scuffed-code/icu4c/source/common/propname.h
George Rhoten a4393f8db9 ICU-2135 Don't use static variables in headers.
Make these C++ classes a part of the ICU namespace.
Use static const arrays for strings instead of pointers to strings.

X-SVN-Rev: 10677
2002-12-14 09:05:17 +00:00

416 lines
12 KiB
C++

/*
**********************************************************************
* Copyright (c) 2002, International Business Machines
* Corporation and others. All Rights Reserved.
**********************************************************************
* Author: Alan Liu
* Created: October 30 2002
* Since: ICU 2.4
**********************************************************************
*/
#ifndef PROPNAME_H
#define PROPNAME_H
#include "unicode/utypes.h"
#include "unicode/uchar.h"
#include "uprops.h"
class Builder;
U_NAMESPACE_BEGIN
// This header defines the in-memory layout of the property names data
// structure representing the UCD data files PropertyAliases.txt and
// PropertyValueAliases.txt. It is used by:
// propname.cpp - reads data
// genpname - creates data
//----------------------------------------------------------------------
// UDataMemory structure and signatures
#define PNAME_DATA_NAME "pnames"
#define PNAME_DATA_TYPE "icu"
// Fields in UDataInfo:
// PNAME_SIG[] is encoded as numeric literals for compatibility with the HP compiler
#define PNAME_SIG_0 ((uint8_t)0x70) /* p */
#define PNAME_SIG_1 ((uint8_t)0x6E) /* n */
#define PNAME_SIG_2 ((uint8_t)0x61) /* a */
#define PNAME_SIG_3 ((uint8_t)0x6D) /* m */
#define PNAME_FORMAT_VERSION ((int8_t)1) /* formatVersion[0] */
/**
* An offset from the start of the pnames data to a contained entity.
* This must be a signed value, since negative offsets are used as an
* end-of-list marker. Offsets to actual objects are non-zero. A
* zero offset indicates an absent entry; this corresponds to aliases
* marked "n/a" in the original Unicode data files.
*/
typedef int16_t Offset; // must be signed
#define MAX_OFFSET 0x7FFF
/**
* A generic value for a property or property value. Typically an
* enum from uchar.h, but sometimes a non-enum value. It must be
* large enough to accomodate the largest enum value, which as of this
* writing is the largest general category mask. Need not be signed
* but may be. Typically it doesn't matter, since the caller will
* cast it to the proper type before use. Takes the special value
* UCHAR_INVALID_CODE for invalid input.
*/
typedef int32_t EnumValue;
//----------------------------------------------------------------------
// ValueMap
/**
* For any top-level property that has named values (binary and
* enumerated properties), there is a ValueMap object. This object
* maps from enum values to two other maps. One goes from value enums
* to value names. The other goes from value names to value enums.
*
* The value enum values may be contiguous or disjoint. If they are
* contiguous then the enumToName_offset is nonzero, and the
* ncEnumToName_offset is zero. Vice versa if the value enums are
* disjoint.
*
* There are n of these objects, where n is the number of binary
* properties + the number of enumerated properties.
*/
struct ValueMap {
// -- begin pnames data --
// Enum=>name EnumToOffset / NonContiguousEnumToOffset objects.
// Exactly one of these will be nonzero.
Offset enumToName_offset;
Offset ncEnumToName_offset;
Offset nameToEnum_offset; // Name=>enum data
// -- end pnames data --
};
//----------------------------------------------------------------------
// PropertyAliases class
/**
* A class encapsulating access to the memory-mapped data representing
* property aliases and property value aliases (pnames). The class
* MUST have no v-table and declares certain methods inline -- small
* methods and methods that are called from only one point.
*
* The data members in this class correspond to the in-memory layout
* of the header of the pnames data.
*/
class PropertyAliases {
// -- begin pnames data --
// Enum=>name EnumToOffset object for binary and enumerated
// properties
Offset enumToName_offset;
// Name=>enum data for binary & enumerated properties
Offset nameToEnum_offset;
// Enum=>offset EnumToOffset object mapping enumerated properties
// to ValueMap objects
Offset enumToValue_offset;
// The following are needed by external readers of this data.
// We don't use them ourselves.
int16_t total_size; // size in bytes excluding the udata header
Offset valueMap_offset; // offset to start of array
int16_t valueMap_count; // number of entries
Offset nameGroupPool_offset; // offset to start of array
int16_t nameGroupPool_count; // number of entries (not groups)
Offset stringPool_offset; // offset to start of pool
int16_t stringPool_count; // number of strings (not size in bytes)
// -- end pnames data --
friend class ::Builder;
const ValueMap* getValueMap(EnumValue prop) const;
const char* chooseNameInGroup(Offset offset,
UPropertyNameChoice choice) const;
public:
inline const int8_t* getPointer(Offset o) const {
return ((const int8_t*) this) + o;
}
inline const int8_t* getPointerNull(Offset o) const {
return o ? getPointer(o) : NULL;
}
inline const char* getPropertyName(EnumValue prop,
UPropertyNameChoice choice) const;
inline EnumValue getPropertyEnum(const char* alias) const;
inline const char* getPropertyValueName(EnumValue prop, EnumValue value,
UPropertyNameChoice choice) const;
inline EnumValue getPropertyValueEnum(EnumValue prop,
const char* alias) const;
};
//----------------------------------------------------------------------
// EnumToOffset
/**
* A generic map from enum values to Offsets. The enum values must be
* contiguous, from enumStart to enumLimit. The Offset values may
* point to anything.
*/
class EnumToOffset {
// -- begin pnames data --
EnumValue enumStart;
EnumValue enumLimit;
Offset _offsetArray; // [array of enumLimit-enumStart]
// -- end pnames data --
friend class ::Builder;
Offset* getOffsetArray() {
return &_offsetArray;
}
const Offset* getOffsetArray() const {
return &_offsetArray;
}
static int32_t getSize(int32_t n) {
return sizeof(EnumToOffset) + sizeof(Offset) * (n - 1);
}
public:
Offset getOffset(EnumValue enumProbe) const {
if (enumProbe < enumStart ||
enumProbe >= enumLimit) {
return 0; // not found
}
const Offset* p = getOffsetArray();
return p[enumProbe - enumStart];
}
};
//----------------------------------------------------------------------
// NonContiguousEnumToOffset
/**
* A generic map from enum values to Offsets. The enum values may be
* disjoint. If they are contiguous, an EnumToOffset should be used
* instead. The Offset values may point to anything.
*/
class NonContiguousEnumToOffset {
// -- begin pnames data --
int32_t count;
EnumValue _enumArray; // [array of count]
// Offset _offsetArray; // [array of count] after enumValue[count-1]
// -- end pnames data --
friend class ::Builder;
EnumValue* getEnumArray() {
return &_enumArray;
}
const EnumValue* getEnumArray() const {
return &_enumArray;
}
Offset* getOffsetArray() {
return (Offset*) (getEnumArray() + count);
}
const Offset* getOffsetArray() const {
return (Offset*) (getEnumArray() + count);
}
static int32_t getSize(int32_t n) {
return sizeof(int32_t) + (sizeof(EnumValue) + sizeof(Offset)) * n;
}
public:
Offset getOffset(EnumValue enumProbe) const {
const EnumValue* e = getEnumArray();
const Offset* p = getOffsetArray();
// linear search; binary later if warranted
// (binary is not faster for short lists)
for (int32_t i=0; i<count; ++i) {
if (e[i] < enumProbe) continue;
if (e[i] > enumProbe) break;
return p[i];
}
return 0; // not found
}
};
//----------------------------------------------------------------------
// NameToEnum
/**
* A map from names to enum values.
*/
class NameToEnum {
// -- begin pnames data --
int32_t count; // number of entries
EnumValue _enumArray; // [array of count] EnumValues
// Offset _nameArray; // [array of count] offsets to names
// -- end pnames data --
friend class ::Builder;
EnumValue* getEnumArray() {
return &_enumArray;
}
const EnumValue* getEnumArray() const {
return &_enumArray;
}
Offset* getNameArray() {
return (Offset*) (getEnumArray() + count);
}
const Offset* getNameArray() const {
return (Offset*) (getEnumArray() + count);
}
static int32_t getSize(int32_t n) {
return sizeof(int32_t) + (sizeof(Offset) + sizeof(EnumValue)) * n;
}
public:
EnumValue getEnum(const char* alias, const PropertyAliases& data) const {
const Offset* n = getNameArray();
const EnumValue* e = getEnumArray();
// linear search; binary later if warranted
// (binary is not faster for short lists)
for (int32_t i=0; i<count; ++i) {
const char* name = (const char*) data.getPointer(n[i]);
int32_t c = uprv_comparePropertyNames(alias, name);
if (c > 0) continue;
if (c < 0) break;
return e[i];
}
return UCHAR_INVALID_CODE;
}
};
/*----------------------------------------------------------------------
*
* In-memory layout. THIS IS NOT A STANDALONE DOCUMENT. It goes
* together with above C++ declarations and gives an overview.
*
* See above for definitions of Offset and EnumValue. Also, refer to
* above class declarations for the "bottom line" on data layout.
*
* Sizes:
* '*_offset' is an Offset (see above)
* 'count' members are typically int32_t (see above declarations)
* 'enumArray' is an array of EnumValue (see above)
* 'offsetArray' is an array of Offset (see above)
* 'nameArray' is an array of Offset (see above)
* 'enum*' is an EnumValue (see above)
* '*Array [x n]' means that *Array has n elements
*
* References:
* Instead of pointers, this flat data structure contains offsets.
* All offsets are relative to the start of 'header'. A notation
* is used to indicate what structure each offset points to:
* 'foo (>x)' the offset(s) in foo point to structure x
*
* Structures:
* Each structure is assigned a number, except for the header,
* which is called 'header'. The numbers are not contiguous
* for historical reasons. Some structures have sub-parts
* that are denoted with a letter, e.g., "5a".
*
* BEGIN LAYOUT
* ============
* header:
* enumToName_offset (>0)
* nameToEnum_offset (>2)
* enumToValue_offset (>3)
* (alignment padding build in to header)
*
* 0: # NonContiguousEnumToOffset obj for props => name groups
* count
* enumArray [x count]
* offsetArray [x count] (>98)
*
* => pad to next 4-byte boundary
*
* (1: omitted -- no longer used)
*
* 2: # NameToEnum obj for binary & enumerated props
* count
* enumArray [x count]
* nameArray [x count] (>99)
*
* => pad to next 4-byte boundary
*
* 3: # NonContiguousEnumToOffset obj for enumerated props => ValueMaps
* count
* enumArray [x count]
* offsetArray [x count] (>4)
*
* => pad to next 4-byte boundary
*
* 4: # ValueMap array [x one for each enumerated prop i]
* enumToName_offset (>5a +2*i) one of these two is NULL, one is not
* ncEnumToName_offset (>5b +2*i)
* nameToEnums_offset (>6 +2*i)
*
* => pad to next 4-byte boundary
*
* for each enumerated prop (either 5a or 5b):
*
* 5a: # EnumToOffset for enumerated prop's values => name groups
* enumStart
* enumLimit
* offsetArray [x enumLimit - enumStart] (>98)
*
* => pad to next 4-byte boundary
*
* 5b: # NonContiguousEnumToOffset for enumerated prop's values => name groups
* count
* enumArray [x count]
* offsetArray [x count] (>98)
*
* => pad to next 4-byte boundary
*
* 6: # NameToEnum for enumerated prop's values
* count
* enumArray [x count]
* nameArray [x count] (>99)
*
* => pad to next 4-byte boundary
*
* 98: # name group pool {NGP}
* [array of Offset values] (>99)
*
* 99: # string pool {SP}
* [pool of nul-terminated char* strings]
*/
U_NAMESPACE_END
#endif
//eof