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See the demo-description:

PARAMFILE1.ini
[Section1]
Param1=SomeParam1Value
Param2=SomeParam2Value
...
[Section2]
Param1Sec2=SomeParam1Value
Param2Sec2=SomeParam2Value
...
PARAMFILE2.ini
[Section1]
Param1Sec1=SomeParam1Value
...

Structure of these files are like the standard Windows ini-files. Application has a number of calls like this:
char Param[128];
// Read Param1Sec1 value from file "PARAMFILE2.ini", section "Section1" ReadIniParameters("PARAMFILE2.ini", "Section1", "Param1Sec1", &Param);

It is required to analyze different methods of creating the well-ordered data lists, which allow to provide the maximum access speed and to choose the most optimal. Main requirement is the speed, because 1) these functions are called quite often; 2) the application is written in C, but binaries are executed by something like virtual Forth machine.

So functions like ReadIniParameters should be optimized for speed.

Comments:
Used programming language is C (ANSI).
Time-consuming building of indexes for access to the configuration data is allowed on the initialization stage.

Solution:
I performed analysis of different algorithms for sorting and building index files. I decided to use CRC (CRC16) for indexes and to used “normalized” CRC value, in that way used the hashing method. One of the reasons of this choice is existence of the System CRC16 API function which can quickly calculate CRC16 of the data block by application request.
...
Description of the index file creation:
Summary number of parameters in all sections and all files is Nparams. When adding a new parameter from the INI file to the index file, following actions are taking place:

char FullParamName[128];
// Create index for each parametr
strcpy(FullParamName, FileName); //example:FullParamName="FILE1.INI"
strcat(FullParamName, SectName); //example:FullParamName="FILE1.INISection4"
strcat(FullParamName, ParamName); //example:"FILE1.INISection4Param8"
// Calculate CRC from "Full Parametr name"
tmpCRC= CalculateBlockCRC16(strlen(FullParamName), &FullParamName);
// "Normalize" CRC for index file
tmpCRC= tmpCRC/NParams;

Each parameter is added to the index file based on the tmpCRC value. Index file consists of the Nparams records, each contains a set of references to the real values FileName+SectName+ParamName. In the common case there can be more than one refernces, because of the CRC16 collisions. In this case references will link to the different parameters and we need to compare them in the series:

Index file
...
CRC16_j-1/NParams
CRC16_j/NParams -> link to (File+Sect+Param)1, (File+Sect+Param)2...
...
When requesting the parameter’s value, ReadIniParameters function calculates the CRC16 from the (FileName+SectName+ParamName). Using the normalized value (CRC16/NParams) it quickly selects (using lseek) the small set of references to the real values of (FileName+SectName+ParamName) to check and compares them for the exact equality:

typedef struct tag_tIndexRecord
{
long ParamLink; // Link to real FileName, Section, ParamName
long NextIndexRec; // Link to next index (if exists)
} tIndexRecord;

int ReadIniParameters(char *FileName, char *Section, char *Param, char *Result)
{
WORD tmpCRC; char FullParamName[128]; int h;
tIndexRecord InRec;
tFileSecParam FileSecParam; // Calculate CRC from "Full Parameter name"

strcpy(FullParamName, FileName);
strcat(FullParamName, Section); strcat(FullParamName, Param);
tmpCRC= CalculateBlockCRC16(strlen(FullParamName), &FullParamName); // "Normalize" CRC for index file
tmpCRC= tmpCRC/NParams;

// Read first index record
if ( (h= open("fileind.ind", O_RDWR)) < 0 ) return(0);
lseek(h, tmpCRC*sizeof(tIndexRecord), SEEK_SET);
read(h, InRec, sizeof(tIndexRecord));
while ( InRec.ParamLink != -1 )
{
lseek(h, ParamLink, SEEK_SET);
read(h, FileSecParam, sizeof(tFileSecParam));
if ( !strcmp(FileSecParam.File, FileName) &&
...

This algorithm allows to get configuration parameters at a high speed, and it’s speed very slowly grows with increasing the summary number of parameters Nparams.

 

PSR1257
спс

 

MrMiXeR
http://www.wasm.ru/forum/viewtopic.php?pid=323810#p323810 => п3 в ответе

 

Я всегда говорил, если хотите использовать switch, if-else, for, do-while,
то программируйте на си, нечего асм загромждать этими конструкциями.

 

все. всем спасибо. вопрос закрыт

 

Microedition
ну почему си можно и на асме

ИМХО:
первое что небходимо - принести в жертву некоторую часть быстродействия другими словами отдавать себе полный отчет в том что строящийся механизм не будет супер быстрым

второе что нужно - разработать макос так чтоб вым было удобно
мне например удобно так в 16 разрядных дос проектах

Код (Text):

1. ;=======[ STRUCTURE ]=============================
2. Word_far\
3.     STRUC
4. Word_far_ID\
5.     WORD    ?
6. Word_far_label\
7.     DWORD   ?
8. Word_far\
9.     ENDS
10.  
11. ...
12.  
13. ;;======[ MACRO ]=================================
14. @Seek_by_WORD\
15.     MACRO\
16.         switch:req,\
17.         segment_register:req,\
18.         index_register:req,\
19.         power:req
20.     LOCAL\
21.         $next,\
22.         $exit
23.     ;;----------------------------------------
24. $next:
25.     mov AX,WORD PTR\
26.         segment_register:[index_register]
27.     IF  @Fault
28.     cmp AX,@Fault
29.     ELSE
30.     or  AX,AX
31.     ENDIF
32.     je  $exit
33.     cmp AX,WORD PTR switch
34.     je  $exit
35.     sub index_register,power
36.     jmp\
37.     short   $next
38. $exit:
39.     ;;----------------------------------------
40.     ENDM
41.  
42. ....
43.  
44.     Word_far\
45.         <@Fault,Method_Fx>
46.     Word_far\
47.         <@Key_enter,Method_Enter>
48.     Word_far\
49.         <@Key_tab,Main_Method_Tab>
50.  
51. S0_Branches\
52.     LABEL   Word_far
53.  
54. ...
55.  
56. @Load_DS_SI\
57.         S0_Branches-SIZE(Word_far)
58. @Seek_by_WORD\
59.         DX,DS,SI,<SIZE(Word_far)>
60.     stc
61.     call    (Word_far PTR[SI])\
62.         .Word_far_label

 

упс опоздал