/* $Id: $ */
/** @file
 *
 * kProfile Mark 2 - Debug Info Reader
 *
 * Copyright (c) 2006 knut st. osmundsen <bird-src-spam@anduin.net.de>
 *
 *
 * This file is part of kLIBC.
 *
 * kLIBC is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * kLIBC is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with kLIBC; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */


/*******************************************************************************
*   Header Files                                                               *
*******************************************************************************/
#include <iprt/file.h>
#include <iprt/string.h>
#include <iprt/err.h>
#include <iprt/assert.h>
#include <iprt/alloc.h>

#include "DBGInternal.h"
#include "internal/ldrMZ.h"
#include "internal/ldrPE.h"



/**
 * Opens the debug info for a specified executable module.
 *
 * @returns IPRT status code.
 * @param   pszModulePath       The path to the executable module.
 * @param   ppDbgMod            Where to store the debug module handle.
 */
RTDECL(int) RTDbgModuleOpen(const char *pszModulePath, PRTDBGMOD *ppDbgMod)
{
    /*
     * Validate input.
     */
    AssertMsgReturn(VALID_PTR(pszModulePath), ("%p\n", pszModulePath), VERR_INVALID_POINTER);
    AssertMsgReturn(*pszModulePath, ("%p\n", pszModulePath), VERR_INVALID_PARAMETER);
    AssertMsgReturn(VALID_PTR(ppDbgMod), ("%p\n", ppDbgMod), VERR_INVALID_POINTER);
    *ppDbgMod = NULL;

    /*
     * The file and try figure out the format.
     */
    RTFILE File;
    int rc = RTFileOpen(&File, pszModulePath, RTFILE_O_READ | RTFILE_O_DENY_WRITE | RTFILE_O_OPEN);
    if (RT_FAILURE(rc))
        return rc;

    RTFOFF offHdr = 0;
    union
    {
        uint32_t    au32[4];
        uint16_t    au16[8];
        uint8_t     ab[16];
    } Buf;
    rc = RTFileRead(File, &Buf, sizeof(Buf), NULL);
    if (    RT_SUCCESS(rc)
        &&  Buf.au16[0] == IMAGE_DOS_SIGNATURE)
    {
        /* new header? */
        uint32_t offNewHeader;
        rc = RTFileReadAt(File, OFFSETOF(IMAGE_DOS_HEADER, e_lfanew), &offNewHeader, sizeof(offNewHeader), NULL);
        if (RT_SUCCESS(rc) && offNewHeader)
        {
            offHdr = offNewHeader;
            rc = RTFileReadAt(File, offNewHeader, &Buf, sizeof(Buf), NULL);
        }
    }
    if (RT_SUCCESS(rc))
    {
        if (Buf.au16[0] == IMAGE_DOS_SIGNATURE)
            rc = VERR_NOT_SUPPORTED;
#ifdef IMAGE_NE_SIGNATURE
        else if (Buf.au16[0] == IMAGE_NE_SIGNATURE)
            rc = VERR_NOT_SUPPORTED;
#endif
#ifdef IMAGE_LX_SIGNATURE
        else if (Buf.au16[0] == IMAGE_LX_SIGNATURE)
            rc = VERR_NOT_SUPPORTED;
#endif
#ifdef IMAGE_LE_SIGNATURE
        else if (Buf.au16[0] == IMAGE_LE_SIGNATURE)
            rc = VERR_NOT_SUPPORTED;
#endif
#ifdef IMAGE_ELF_SIGNATURE
        else if (Buf.au32[0] == IMAGE_ELF_SIGNATURE)
            rc = VERR_NOT_SUPPORTED;
#endif
#ifdef IMAGE_NT_SIGNATURE
        else if (Buf.au32[0] == IMAGE_NT_SIGNATURE)
            rc = rtDbgModPEOpen(File, offHdr, pszModulePath, ppDbgMod);
#endif
        /** @todo there are a number of text file formats too which I want to support. */
        else
            rc = VERR_NOT_SUPPORTED;

    }

    if (RT_FAILURE(rc))
        RTFileClose(File);
    return rc;
}


/**
 * Validates a debug module handle.
 * All necessary asserting will be taken care of here.
 *
 * @returns True / false.
 * @param   pMod        The debug module handle.
 */
DECLINLINE(bool) rtDbgModIsValid(PRTDBGMOD pMod)
{
    AssertMsgReturn(VALID_PTR(pMod), ("%p", pMod), false);
    AssertMsgReturn(pMod->u32Magic == RTDBGMOD_MAGIC, ("%RX32", pMod->u32Magic), false);
    AssertMsgReturn(VALID_PTR(pMod->pOps), ("%p", pMod->pOps), false);
    return true;
}


/**
 * Closes the module.
 *
 * @returns IPRT status code.
 * @param   pMod        The module handle.
 */
RTDECL(int) RTDbgModuleClose(PRTDBGMOD pMod)
{
    if (!rtDbgModIsValid(pMod))
        return VERR_INVALID_PARAMETER;

    int rc = pMod->pOps->pfnClose(pMod);
    if (RT_SUCCESS(rc))
        RTMemFree(pMod);
    return rc;
}


/**
 * Gets a symbol by segment:offset.
 * This will be approximated to the nearest symbol if there is no exact match.
 *
 * @returns IPRT status code.
 * @param   pMod        The module.
 * @param   iSegment    The segment this offset is relative to.
 *                      The -1 segment is special, it means that the addres is relative to
 *                      the image base. The image base is where the first bit of the image
 *                      is mapped during load.
 * @param   off         The offset into the segment.
 * @param   pSym        Where to store the symbol details.
 */
RTDECL(int) RTDbgModuleQuerySymbol(PRTDBGMOD pMod, int32_t iSegment, RTUINTPTR off, PRTDBGSYMBOL pSym)
{
    if (!rtDbgModIsValid(pMod))
        return VERR_INVALID_PARAMETER;
    AssertMsgReturn(VALID_PTR(pSym), ("%p", pSym), VERR_INVALID_POINTER);

    return pMod->pOps->pfnQuerySymbol(pMod, iSegment, off, pSym);
}


/**
 * Gets & allocates a symbol by segment:offset.
 * This will be approximated to the nearest symbol if there is no exact match.
 *
 * @returns IPRT status code.
 * @param   pMod        The module.
 * @param   iSegment    The segment this offset is relative to.
 *                      The -1 segment is special, it means that the addres is relative to
 *                      the image base. The image base is where the first bit of the image
 *                      is mapped during load.
 * @param   off         The offset into the segment.
 * @param   ppSym       Where to store the pointer to the symbol info.
 *                      Free the returned symbol using RTDbgSymbolFree().
 */
RTDECL(int) RTDbgModuleQuerySymbolA(PRTDBGMOD pMod, int32_t iSegment, RTUINTPTR off, PPRTDBGSYMBOL ppSym)
{
    AssertMsgReturn(VALID_PTR(ppSym), ("%p\n", ppSym), VERR_INVALID_POINTER);

    RTDBGSYMBOL Sym;
    int rc = RTDbgModuleQuerySymbol(pMod, iSegment, off, &Sym);
    if (RT_SUCCESS(rc))
    {
        *ppSym = RTDbgSymbolDup(&Sym);
        if (!*ppSym)
            rc = VERR_NO_MEMORY;
    }
    else
        *ppSym = NULL;
    return rc;
}


/**
 * Gets a line number entry by segment:offset.
 * This will be approximated to the nearest line number there is no exact match.
 *
 * @returns IPRT status code.
 * @param   pMod        The module.
 * @param   iSegment    The segment this offset is relative to.
 *                      The -1 segment is special, it means that the addres is relative to
 *                      the image base. The image base is where the first bit of the image
 *                      is mapped during load.
 * @param   off         The offset into the segment.
 * @param   pLine       Where to store the line number details.
 */
RTDECL(int) RTDbgModuleQueryLine(PRTDBGMOD pMod, int32_t iSegment, RTUINTPTR off, PRTDBGLINE pLine)
{
    if (!rtDbgModIsValid(pMod))
        return VERR_INVALID_PARAMETER;
    AssertMsgReturn(VALID_PTR(pLine), ("%p", pLine), VERR_INVALID_POINTER);

    return pMod->pOps->pfnQueryLine(pMod, iSegment, off, pLine);
}


/**
 * Gets & allocates a line number entry by segment:offset.
 * This will be approximated to the nearest line number there is no exact match.
 *
 * @returns IPRT status code.
 * @param   pMod        The module.
 * @param   iSegment    The segment this offset is relative to.
 *                      The -1 segment is special, it means that the addres is relative to
 *                      the image base. The image base is where the first bit of the image
 *                      is mapped during load.
 * @param   off         The offset into the segment.
 * @param   ppLine      Where to store the pointer to the line number info.
 *                      Free the returned line number using RTDbgLineFree().
 */
RTDECL(int) RTDbgModuleQueryLineA(PRTDBGMOD pMod, int32_t iSegment, RTUINTPTR off, PPRTDBGLINE ppLine)
{
    AssertMsgReturn(VALID_PTR(ppLine), ("%p\n", ppLine), VERR_INVALID_POINTER);

    RTDBGLINE Line;
    int rc = RTDbgModuleQueryLine(pMod, iSegment, off, &Line);
    if (RT_SUCCESS(rc))
    {
        *ppLine = RTDbgLineDup(&Line);
        if (!*ppLine)
            rc = VERR_NO_MEMORY;
    }
    else
        *ppLine = NULL;
    return rc;
}