view mercurial/util.h @ 28487:98d98a645e9d

changelog: add class to represent parsed changelog revisions

Currently, changelog entries are parsed into their respective
components at read time. Many operations are only interested
in a subset of fields of a changelog entry. The parsing and
storing of all the fields adds avoidable overhead.

This patch introduces the "changelogrevision" class. It takes
changelog raw text and exposes the parsed results as attributes.
The code for parsing changelog entries has been moved into its
construction function. changelog.read() has been modified to use
the new class internally while maintaining its existing API.
Future patches will make revision parsing lazy.

We implement the construction function of the new class with
__new__ instead of __init__ so we can use a named tuple to
represent the empty revision. This saves overhead and complexity
of coercing later versions of this class to represent an empty
instance.

While we are here, we add a method on changelog to obtain an
instance of the new type.

The overhead of constructing the new class regresses performance
of revsets accessing this data:

author(mpm)
0.896565
0.929984

desc(bug)
0.887169
0.935642 105%

date(2015)
0.878797
0.908094

extra(rebase_source)
0.865446
0.922624 106%

author(mpm) or author(greg)
1.801832
1.902112 105%

author(mpm) or desc(bug)
1.812438
1.860977

date(2015) or branch(default)
0.968276
1.005824

author(mpm) or desc(bug) or date(2015) or extra(rebase_source)
3.656193
3.743381

Once lazy parsing is implemented, these revsets will all be faster
than before. There is no performance change on revsets that do not
access this data. There /could/ be a performance regression on
operations that perform several changelog reads. However, I can't
think of anything outside of revsets and `hg log` (basically the
same as a revset) that would be impacted.

/*
 util.h - utility functions for interfacing with the various python APIs.

 This software may be used and distributed according to the terms of
 the GNU General Public License, incorporated herein by reference.
*/

#ifndef _HG_UTIL_H_
#define _HG_UTIL_H_

#if PY_MAJOR_VERSION >= 3

#define IS_PY3K
#define PyInt_FromLong PyLong_FromLong
#define PyInt_AsLong PyLong_AsLong

/*
 Mapping of some of the python < 2.x PyString* functions to py3k's PyUnicode.

 The commented names below represent those that are present in the PyBytes
 definitions for python < 2.6 (below in this file) that don't have a direct
 implementation.
*/

#define PyStringObject PyUnicodeObject
#define PyString_Type PyUnicode_Type

#define PyString_Check PyUnicode_Check
#define PyString_CheckExact PyUnicode_CheckExact
#define PyString_CHECK_INTERNED PyUnicode_CHECK_INTERNED
#define PyString_AS_STRING PyUnicode_AsLatin1String
#define PyString_GET_SIZE PyUnicode_GET_SIZE

#define PyString_FromStringAndSize PyUnicode_FromStringAndSize
#define PyString_FromString PyUnicode_FromString
#define PyString_FromFormatV PyUnicode_FromFormatV
#define PyString_FromFormat PyUnicode_FromFormat
/* #define PyString_Size PyUnicode_GET_SIZE */
/* #define PyString_AsString */
/* #define PyString_Repr */
#define PyString_Concat PyUnicode_Concat
#define PyString_ConcatAndDel PyUnicode_AppendAndDel
#define _PyString_Resize PyUnicode_Resize
/* #define _PyString_Eq */
#define PyString_Format PyUnicode_Format
/* #define _PyString_FormatLong */
/* #define PyString_DecodeEscape */
#define _PyString_Join PyUnicode_Join
#define PyString_Decode PyUnicode_Decode
#define PyString_Encode PyUnicode_Encode
#define PyString_AsEncodedObject PyUnicode_AsEncodedObject
#define PyString_AsEncodedString PyUnicode_AsEncodedString
#define PyString_AsDecodedObject PyUnicode_AsDecodedObject
#define PyString_AsDecodedString PyUnicode_AsDecodedUnicode
/* #define PyString_AsStringAndSize */
#define _PyString_InsertThousandsGrouping _PyUnicode_InsertThousandsGrouping

#endif /* PY_MAJOR_VERSION */

#ifdef _WIN32
#ifdef _MSC_VER
/* msvc 6.0 has problems */
#define inline __inline
typedef signed char int8_t;
typedef short int16_t;
typedef long int32_t;
typedef __int64 int64_t;
typedef unsigned char uint8_t;
typedef unsigned short uint16_t;
typedef unsigned long uint32_t;
typedef unsigned __int64 uint64_t;
#else
#include <stdint.h>
#endif
#else
/* not windows */
#include <sys/types.h>
#if defined __BEOS__ && !defined __HAIKU__
#include <ByteOrder.h>
#else
#include <arpa/inet.h>
#endif
#include <inttypes.h>
#endif

#if defined __hpux || defined __SUNPRO_C || defined _AIX
#define inline
#endif

#ifdef __linux
#define inline __inline
#endif

typedef struct {
	PyObject_HEAD
	char state;
	int mode;
	int size;
	int mtime;
} dirstateTupleObject;

extern PyTypeObject dirstateTupleType;
#define dirstate_tuple_check(op) (Py_TYPE(op) == &dirstateTupleType)

static inline uint32_t getbe32(const char *c)
{
	const unsigned char *d = (const unsigned char *)c;

	return ((d[0] << 24) |
		(d[1] << 16) |
		(d[2] << 8) |
		(d[3]));
}

static inline int16_t getbeint16(const char *c)
{
	const unsigned char *d = (const unsigned char *)c;

	return ((d[0] << 8) |
		(d[1]));
}

static inline uint16_t getbeuint16(const char *c)
{
	const unsigned char *d = (const unsigned char *)c;

	return ((d[0] << 8) |
		(d[1]));
}

static inline void putbe32(uint32_t x, char *c)
{
	c[0] = (x >> 24) & 0xff;
	c[1] = (x >> 16) & 0xff;
	c[2] = (x >> 8) & 0xff;
	c[3] = (x) & 0xff;
}

static inline double getbefloat64(const char *c)
{
	const unsigned char *d = (const unsigned char *)c;
	double ret;
	int i;
	uint64_t t = 0;
	for (i = 0; i < 8; i++) {
		t = (t<<8) + d[i];
	}
	memcpy(&ret, &t, sizeof(t));
	return ret;
}

/* This should be kept in sync with normcasespecs in encoding.py. */
enum normcase_spec {
	NORMCASE_LOWER = -1,
	NORMCASE_UPPER = 1,
	NORMCASE_OTHER = 0
};

#define MIN(a, b) (((a)<(b))?(a):(b))
/* VC9 doesn't include bool and lacks stdbool.h based on my searching */
#if defined(_MSC_VER) || __STDC_VERSION__ < 199901L
#define true 1
#define false 0
typedef unsigned char bool;
#else
#include <stdbool.h>
#endif

#endif /* _HG_UTIL_H_ */