/**

 * WinPR: Windows Portable Runtime

 * File Functions

 *

 * Copyright 2012 Marc-Andre Moreau <marcandre.moreau@gmail.com>

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

#include <winpr/config.h>

#include <winpr/crt.h>

#include <winpr/handle.h>

#include <winpr/file.h>

#ifdef WINPR_HAVE_UNISTD_H

#include <unistd.h>

#endif

#ifdef WINPR_HAVE_FCNTL_H

#include <fcntl.h>

#endif

#include "../log.h"

#define TAG WINPR_TAG("file")

/**

 * File System Behavior in the Microsoft Windows Environment:

 * http://download.microsoft.com/download/4/3/8/43889780-8d45-4b2e-9d3a-c696a890309f/File%20System%20Behavior%20Overview.pdf

 */

LPSTR FilePatternFindNextWildcardA(LPCSTR lpPattern, DWORD* pFlags)

{

  WINPR_ASSERT(lpPattern);

  WINPR_ASSERT(pFlags);

  *pFlags = 0;

  char* lpWildcard = strpbrk(lpPattern, "*?~");

  if (lpWildcard)

  {

    if (*lpWildcard == '*')

    {

      *pFlags = WILDCARD_STAR;

      return lpWildcard;

    }

    else if (*lpWildcard == '?')

    {

      *pFlags = WILDCARD_QM;

      return lpWildcard;

    }

    else if (*lpWildcard == '~')

    {

      if (lpWildcard[1] == '*')

      {

        *pFlags = WILDCARD_DOS_STAR;

        return lpWildcard;

      }

      else if (lpWildcard[1] == '?')

      {

        *pFlags = WILDCARD_DOS_QM;

        return lpWildcard;

      }

      else if (lpWildcard[1] == '.')

      {

        *pFlags = WILDCARD_DOS_DOT;

        return lpWildcard;

      }

    }

  }

  return nullptr;

}

static BOOL FilePatternMatchSubExpressionA(LPCSTR lpFileName, size_t cchFileName, LPCSTR lpX,

                                           size_t cchX, LPCSTR lpY, size_t cchY, LPCSTR lpWildcard,

                                           LPCSTR* ppMatchEnd)

{

  LPCSTR lpMatch = nullptr;

  if (!lpFileName)

    return FALSE;

  if (*lpWildcard == '*')

  {

    /*

     *                            S

     *                         <-----<

     *                      X  |     |  e       Y

     * X * Y ==        (0)----->-(1)->-----(2)-----(3)

     */

    /*

     * State 0: match 'X'

     */

    if (_strnicmp(lpFileName, lpX, cchX) != 0)

      return FALSE;

    /*

     * State 1: match 'S' or 'e'

     *

     * We use 'e' to transition to state 2

     */

    /**

     * State 2: match Y

     */

    if (cchY != 0)

    {

      /* TODO: case insensitive character search */

      lpMatch = strchr(&lpFileName[cchX], *lpY);

      if (!lpMatch)

        return FALSE;

      if (_strnicmp(lpMatch, lpY, cchY) != 0)

        return FALSE;

    }

    else

    {

      lpMatch = &lpFileName[cchFileName];

    }

    /**

     * State 3: final state

     */

    *ppMatchEnd = &lpMatch[cchY];

    return TRUE;

  }

  else if (*lpWildcard == '?')

  {

    /**

     *                     X     S     Y

     * X ? Y ==        (0)---(1)---(2)---(3)

     */

    /*

     * State 0: match 'X'

     *

     * '?' consumes exactly one character at position cchX, so the file

     * name must hold at least cchX + 1 characters. Without this the

     * cchY != 0 branch below reads &lpFileName[cchX + 1], one past the

     * terminator, when cchFileName == cchX.

     */

    if (cchFileName < cchX + 1)

      return FALSE;

    if (_strnicmp(lpFileName, lpX, cchX) != 0)

      return FALSE;

    /*

     * State 1: match 'S'

     */

    /**

     * State 2: match Y

     */

    if (cchY != 0)

    {

      /* TODO: case insensitive character search */

      lpMatch = strchr(&lpFileName[cchX + 1], *lpY);

      if (!lpMatch)

        return FALSE;

      if (_strnicmp(lpMatch, lpY, cchY) != 0)

        return FALSE;

    }

    else

    {

      lpMatch = &lpFileName[cchX + 1];

    }

    /**

     * State 3: final state

     */

    *ppMatchEnd = &lpMatch[cchY];

    return TRUE;

  }

  else if (*lpWildcard == '~')

  {

    WLog_ERR(TAG, "warning: unimplemented '~' pattern match");

    return TRUE;

  }

  return FALSE;

}

BOOL FilePatternMatchA(LPCSTR lpFileName, LPCSTR lpPattern)

{

  BOOL match = 0;

  LPCSTR lpTail = nullptr;

  size_t cchTail = 0;

  DWORD dwFlags = 0;

  DWORD dwNextFlags = 0;

  /**

   * Wild Card Matching

   *

   * '*'  matches 0 or more characters

   * '?'  matches exactly one character

   *

   * '~*' DOS_STAR - matches 0 or more characters until encountering and matching final '.'

   *

   * '~?' DOS_QM - matches any single character, or upon encountering a period or end of name

   *               string, advances the expression to the end of the set of contiguous DOS_QMs.

   *

   * '~.' DOS_DOT - matches either a '.' or zero characters beyond name string.

   */

  if (!lpPattern)

    return FALSE;

  if (!lpFileName)

    return FALSE;

  const size_t cchPattern = strlen(lpPattern);

  const size_t cchFileName = strlen(lpFileName);

  /**

   * First and foremost the file system starts off name matching with the expression “*”.

   * If the expression contains a single wild card character ‘*’ all matches are satisfied

   * immediately. This is the most common wild card character used in Windows and expression

   * evaluation is optimized by looking for this character first.

   */

  if ((lpPattern[0] == '*') && (cchPattern == 1))

    return TRUE;

  /**

   * Windows keeps the MS-DOS meaning of "*.*": every name, also the ones

   * without a dot. Servers use it to list directories (MS-RDPEFS clients

   * receive it in IRP_MN_QUERY_DIRECTORY), so match it the same way.

   */

  if ((cchPattern == 3) && (strcmp(lpPattern, "*.*") == 0))

    return TRUE;

  /**

   * Subsequently evaluation of the “*X” expression is performed. This is a case where

   * the expression starts off with a wild card character and contains some non-wild card

   * characters towards the tail end of the name. This is evaluated by making sure the

   * expression starts off with the character ‘*’ and does not contain any wildcards in

   * the latter part of the expression. The tail part of the expression beyond the first

   * character ‘*’ is matched against the file name at the end uppercasing each character

   * if necessary during the comparison.

   */

  if (lpPattern[0] == '*')

  {

    lpTail = &lpPattern[1];

    cchTail = strlen(lpTail);

    if (!FilePatternFindNextWildcardA(lpTail, &dwFlags))

    {

      /* tail contains no wildcards */

      if (cchFileName < cchTail)

        return FALSE;

      if (_stricmp(&lpFileName[cchFileName - cchTail], lpTail) == 0)

        return TRUE;

      return FALSE;

    }

  }

  /**

   * The remaining expressions are evaluated in a non deterministic

   * finite order as listed below, where:

   *

   * 'S' is any single character

   * 'S-.' is any single character except the final '.'

   * 'e' is a null character transition

   * 'EOF' is the end of the name string

   *

   *                            S

   *                         <-----<

   *                      X  |     |  e       Y

   * X * Y ==        (0)----->-(1)->-----(2)-----(3)

   *

   *

   *                           S-.

   *                         <-----<

   *                      X  |     |  e       Y

   * X ~* Y ==       (0)----->-(1)->-----(2)-----(3)

   *

   *

   *                     X     S     S     Y

   * X ?? Y ==       (0)---(1)---(2)---(3)---(4)

   *

   *

   *                     X     S-.     S-.     Y

   * X ~?~? ==      (0)---(1)-----(2)-----(3)---(4)

   *                        |       |_______|

   *                        |            ^  |

   *                        |_______________|

   *                            ^EOF of .^

   *

   */

  LPCSTR lpWildcard = FilePatternFindNextWildcardA(lpPattern, &dwFlags);

  if (lpWildcard)

  {

    LPCSTR lpMatchEnd = nullptr;

    size_t cchNextWildcard = 0;

    const size_t cchSubPattern = cchPattern;

    LPCSTR lpSubPattern = lpPattern;

    size_t cchSubFileName = cchFileName;

    LPCSTR lpSubFileName = lpFileName;

    size_t cchWildcard = ((dwFlags & WILDCARD_DOS) ? 2 : 1);

    LPCSTR lpNextWildcard =

        FilePatternFindNextWildcardA(&lpWildcard[cchWildcard], &dwNextFlags);

    if (!lpNextWildcard)

    {

      LPCSTR lpX = lpSubPattern;

      if (lpWildcard < lpSubPattern)

        return FALSE;

      const size_t cchX = WINPR_ASSERTING_INT_CAST(size_t, (lpWildcard - lpSubPattern));

      LPCSTR lpY = &lpSubPattern[cchX + cchWildcard];

      if (lpY < lpSubPattern)

        return FALSE;

      const size_t lpYSSubPattern = WINPR_ASSERTING_INT_CAST(size_t, (lpY - lpSubPattern));

      if (cchSubPattern < lpYSSubPattern)

        return FALSE;

      const size_t cchY = cchSubPattern - lpYSSubPattern;

      return FilePatternMatchSubExpressionA(lpSubFileName, cchSubFileName, lpX, cchX, lpY,

                                            cchY, lpWildcard, &lpMatchEnd);

    }

    else

    {

      while (lpNextWildcard)

      {

        if (lpSubFileName < lpFileName)

          return FALSE;

        cchSubFileName =

            cchFileName - WINPR_ASSERTING_INT_CAST(size_t, (lpSubFileName - lpFileName));

        cchNextWildcard = ((dwNextFlags & WILDCARD_DOS) ? 2 : 1);

        LPCSTR lpX = lpSubPattern;

        if (lpWildcard < lpSubPattern)

          return FALSE;

        const size_t cchX = WINPR_ASSERTING_INT_CAST(size_t, (lpWildcard - lpSubPattern));

        LPCSTR lpY = &lpSubPattern[cchX + cchWildcard];

        if (lpNextWildcard < lpWildcard)

          return FALSE;

        const size_t diff = WINPR_ASSERTING_INT_CAST(size_t, (lpNextWildcard - lpWildcard));

        if (diff < cchWildcard)

          return FALSE;

        const size_t cchY = diff - cchWildcard;

        match = FilePatternMatchSubExpressionA(lpSubFileName, cchSubFileName, lpX, cchX,

                                               lpY, cchY, lpWildcard, &lpMatchEnd);

        if (!match)

          return FALSE;

        lpSubFileName = lpMatchEnd;

        cchWildcard = cchNextWildcard;

        lpWildcard = lpNextWildcard;

        dwFlags = dwNextFlags;

        lpNextWildcard =

            FilePatternFindNextWildcardA(&lpWildcard[cchWildcard], &dwNextFlags);

      }

      return TRUE;

    }

  }

  else

  {

    /* no wildcard characters */

    if (_stricmp(lpFileName, lpPattern) == 0)

      return TRUE;

  }

  return FALSE;

}