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Title: C Sructures help
Post by: xandaz on June 16, 2020, 10:14:13 PM

Hey guys. I've been translating unRAR.h and came across some doubts. i know that this is an ASM forum but i'd like to know if someone could translate the following structure. Thanks in advance

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struct RAROpenArchiveDataEx
{
  char         *ArcName;
  wchar_t      *ArcNameW;
  unsigned int  OpenMode;
  unsigned int  OpenResult;
  char         *CmtBuf;
  unsigned int  CmtBufSize;
  unsigned int  CmtSize;
  unsigned int  CmtState;
  unsigned int  Flags;
  UNRARCALLBACK Callback;
  LPARAM        UserData;
  unsigned int  OpFlags;
  wchar_t      *CmtBufW;
  unsigned int  Reserved[25];
};

Thanks guys

Title: Re: C Sructures help
Post by: felipe on June 16, 2020, 11:54:25 PM

Translate to assembly? If that so, even if i don't know this structure i can give hints of the types you can use in an assembly source code (written in the comments):

Code Select


struct RAROpenArchiveDataEx
{
  char         *ArcName;                  ;;;;;;;;;;; Just a pointer to a text buffer (size of each character 1 byte).
  wchar_t      *ArcNameW;            ;;;;;;;;;;; Just a pointer to a text buffer (size of each character 2 bytes i think).
  unsigned int  OpenMode;           ;;;;;;;;;;; A dword.
  unsigned int  OpenResult;           ;;;;;;;;;;; A dword.
  char         *CmtBuf;                     ;;;;;;;;;;; Just a pointer to a text buffer (size of each character 1 byte).
  unsigned int  CmtBufSize;           ;;;;;;;;;;; A dword.
  unsigned int  CmtSize;                 ;;;;;;;;;;; A dword.
  unsigned int  CmtState;               ;;;;;;;;;;; A dword.
  unsigned int  Flags;                     ;;;;;;;;;;; A dword.
  UNRARCALLBACK Callback;            ;;;;;;;;;;;Probably a pointer to some callback function.
  LPARAM        UserData;                ;;;;;;;; dword in 32 bit land, qword in 64 bits land.
  unsigned int  OpFlags;                 ;;;;;;;;;;; A dword.
  wchar_t      *CmtBufW;               ;;;;;;;;;;; Just a pointer to a text buffer (size of each character 2 bytes i think).
  unsigned int  Reserved[25];        ;;;;;;;;;;;Just 25 dwords i guess.
};

Don't know if this structure is defined in windows.inc or win64.inc, if not, there are different kinds of styles of code to write the structure in the data section of your code that you can use. :icon_idea:

Title: Re: C Sructures help
Post by: felipe on June 17, 2020, 12:18:16 AM

Here is the same as above using the classical structure definition in masm 32 bits code (c masters should correct me if i'm wrong):

Code Select


RAROpenArchiveDataEx STRUCT
  ArcName        DWORD      ?
  ArcNameW      DWORD      ?
  OpenMode       DWORD      ?
  OpenResult      DWORD      ?
  CmtBuf          DWORD      ?
  CmtBufSize       DWORD      ?
  CmtState        DWORD      ?
  Flags           DWORD      ?
   _Callback        DWORD      ?
   UserData         DWORD      ?
   OpFlags        DWORD      ?
     Reserved     DWORD      25 dup(?)
RAROpenArchiveDataEx  ENDS

Title: Re: C Sructures help
Post by: TimoVJL on June 17, 2020, 01:52:27 AM

32-bit

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RAROpenArchiveDataEx 152 98h bytes
ArcName          +0h 4h
ArcNameW         +4h 4h
OpenMode         +8h 4h
OpenResult       +Ch 4h
CmtBuf           +10h 4h
CmtBufSize       +14h 4h
CmtSize          +18h 4h
CmtState         +1Ch 4h
Flags            +20h 4h
UserData         +28h 4h
OpFlags          +2Ch 4h
CmtBufW          +30h 4h
Reserved         +34h 64h

64-bit

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RAROpenArchiveDataEx 176 B0h bytes
ArcName          +0h 8h
ArcNameW         +8h 8h
OpenMode         +10h 4h
OpenResult       +14h 4h
CmtBuf           +18h 8h
CmtBufSize       +20h 4h
CmtSize          +24h 4h
CmtState         +28h 4h
Flags            +2Ch 4h
UserData         +38h 8h
OpFlags          +40h 4h
CmtBufW          +44h 8h
Reserved         +4Ch 64h

so PTR just for pointers

Title: Re: C Sructures help
Post by: jj2007 on June 18, 2020, 03:35:21 AM

Quote from: xandaz on June 16, 2020, 10:14:13 PM
Hey guys. I've been translating unRAR.h and came across some doubts. i know that this is an ASM forum but i'd like to know if someone could translate the following structure. Thanks in advance
Code Select Expand
struct RAROpenArchiveDataEx { char *ArcName; wchar_t *ArcNameW; unsigned int OpenMode; unsigned int OpenResult; char *CmtBuf; unsigned int CmtBufSize; unsigned int CmtSize; unsigned int CmtState; unsigned int Flags; UNRARCALLBACK Callback; LPARAM UserData; unsigned int OpFlags; wchar_t *CmtBufW; unsigned int Reserved[25]; };

CStruct2Asm (attached) translates it like this:

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RAROpenArchiveDataEx STRUCT
 ArcName   	LPVOID ?
 ArcNameW  	LPVOID ?
 OpenMode  	DWORD ?
 OpenResult	DWORD ?
 CmtBuf    	LPVOID ?
 CmtBufSize	DWORD ?
 CmtSize   	DWORD ?
 CmtState  	DWORD ?
 Flags     	DWORD ?
 Callback  	UNRARCALLBACK <>
 UserData  	LPARAM ?
 OpFlags   	DWORD ?
 CmtBufW   	LPVOID ?
 Reserved  	dd 25 dup(?)
RAROpenArchiveDataEx ENDS

Usage: copy the C struct, launch the exe

Title: Re: C Sructures help
Post by: xandaz on June 22, 2020, 01:41:53 AM

thanks for the help guys.

Title: Re: C Sructures help
Post by: deeR44 on July 02, 2020, 03:22:03 PM

I'm learning Python. If I need any help with Python, I'm coming right here.

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General => The Campus => Topic started by: xandaz on June 16, 2020, 10:14:13 PM