/* Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.

   Copyright (c) 2008, 2022, MariaDB Corporation.

   This program 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; version 2 of the License.

   This program 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 this program; if not, write to the Free Software

   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1335  USA.

*/

/* TODO: check for overrun of memory for names. */

#include  "mysys_priv.h"

#include  <m_string.h>

#include  <my_dir.h>  /* Structs used by my_dir,includes sys/types */

#include  "mysys_err.h"

#if defined(HAVE_DIRENT_H)

# include <dirent.h>

#else

# define dirent direct

# if defined(HAVE_SYS_NDIR_H)

#  include <sys/ndir.h>

# endif

# if defined(HAVE_SYS_DIR_H)

#  include <sys/dir.h>

# endif

# if defined(HAVE_NDIR_H)

#  include <ndir.h>

# endif

# if defined(_WIN32)

# ifdef __BORLANDC__

# include <dir.h>

# endif

# endif

#endif

#if defined(HAVE_READDIR_R)

#define READDIR(A,B,C) ((errno=readdir_r(A,B,&C)) != 0 || !C)

#else

#define READDIR(A,B,C) (!(C=readdir(A)))

#endif

/*

  We are assuming that directory we are reading is either has less than 

  100 files and so can be read in one initial chunk or has more than 1000

  files and so big increment are suitable.

*/

#define ENTRIES_START_SIZE (8192/sizeof(FILEINFO))

#define ENTRIES_INCREMENT  (65536/sizeof(FILEINFO))

#define NAMES_START_SIZE   32768

static int  comp_names(const void *a, const void *b);

typedef struct {

  MY_DIR        dir;

  DYNAMIC_ARRAY array;

  MEM_ROOT      root;

} MY_DIR_HANDLE;

/* We need this because the caller doesn't know which malloc we've used */

void my_dirend(MY_DIR *dir)

{

  MY_DIR_HANDLE *dirh= (MY_DIR_HANDLE*) dir;

  DBUG_ENTER("my_dirend");

  if (dirh)

  {

    delete_dynamic(&dirh->array);

    free_root(&dirh->root, MYF(0));

    my_free(dirh);

  }

  DBUG_VOID_RETURN;

} /* my_dirend */

        /* Compare in sort of filenames */

static int comp_names(const void *a_, const void *b_)

{

  const struct fileinfo *a= a_;

  const struct fileinfo *b= b_;

  return (strcmp(a->name,b->name));

} /* comp_names */

#if !defined(_WIN32)

static char *directory_file_name (char * dst, const char *src)

{

  /* Process as Unix format: just remove test the final slash. */

  char *end;

  DBUG_ASSERT(strlen(src) < (FN_REFLEN + 1));

  if (src[0] == 0)

    src= (char*) ".";                           /* Use empty as current */

  end= strnmov(dst, src, FN_REFLEN + 1);

  if (end[-1] != FN_LIBCHAR)

  {

    *end++= FN_LIBCHAR;                          /* Add last '/' */

    *end='\0';

  }

  return end;

}

MY_DIR  *my_dir(const char *path, myf MyFlags)

{

  MY_DIR_HANDLE *dirh;

  FILEINFO      finfo;

  DIR   *dirp;

  struct dirent *dp;

  char    tmp_path[FN_REFLEN + 2], *tmp_file;

  char  dirent_tmp[sizeof(struct dirent)+_POSIX_PATH_MAX+1];

  DBUG_ENTER("my_dir");

  DBUG_PRINT("my",("path: '%s' MyFlags: %lu",path,MyFlags));

  tmp_file= directory_file_name(tmp_path, path);

  if (!(dirp= opendir(tmp_path)))

  {

    my_errno= errno;

    goto err_open;

  }

  if (!(dirh= my_malloc(key_memory_MY_DIR, sizeof(*dirh),

                        MYF(MyFlags | MY_ZEROFILL))))

    goto err_alloc;

  if (my_init_dynamic_array(key_memory_MY_DIR, &dirh->array, sizeof(FILEINFO),

                            ENTRIES_START_SIZE, ENTRIES_INCREMENT,

                            MYF(MyFlags)))

    goto error;

  init_alloc_root(key_memory_MY_DIR, &dirh->root, NAMES_START_SIZE,

                  NAMES_START_SIZE, MYF(MyFlags));

  dp= (struct dirent*) dirent_tmp;

  while (!(READDIR(dirp,(struct dirent*) dirent_tmp,dp)))

  {

    MY_STAT statbuf, *mystat= 0;

    if (dp->d_name[0] == '.' &&

        (dp->d_name[1] == '\0' ||

         (dp->d_name[1] == '.' && dp->d_name[2] == '\0')))

      continue;                               /* . or .. */

    if (MyFlags & MY_WANT_STAT)

    {

      mystat= &statbuf;

      bzero(mystat, sizeof(*mystat));

      (void) strmov(tmp_file, dp->d_name);

      (void) my_stat(tmp_path, mystat, MyFlags);

      if (!(mystat->st_mode & MY_S_IREAD))

        continue;

    }

    if (!(finfo.name= strdup_root(&dirh->root, dp->d_name)))

      goto error;

    if (mystat &&

        !((mystat= memdup_root(&dirh->root, mystat, sizeof(*mystat)))))

      goto error;

    finfo.mystat= mystat;

    if (push_dynamic(&dirh->array, (uchar*)&finfo))

      goto error;

  }

  (void) closedir(dirp);

  if (MyFlags & MY_WANT_SORT)

    sort_dynamic(&dirh->array, (qsort_cmp) comp_names);

  dirh->dir.dir_entry= dynamic_element(&dirh->array, 0, FILEINFO *);

  dirh->dir.number_of_files= dirh->array.elements;

  DBUG_RETURN(&dirh->dir);

error:

  my_dirend(&dirh->dir);

err_alloc:

  (void) closedir(dirp);

err_open:

  if (MyFlags & (MY_FAE | MY_WME))

    my_error(EE_DIR, MYF(ME_BELL), path, my_errno);

  DBUG_RETURN(NULL);

} /* my_dir */

#else

/*

*****************************************************************************

** Read long filename using windows routines

*****************************************************************************

*/

MY_DIR  *my_dir(const char *path, myf MyFlags)

{

  MY_DIR_HANDLE *dirh= 0;

  FILEINFO      finfo;

  struct _finddata_t find;

  ushort  mode;

  char    tmp_path[FN_REFLEN], *tmp_file,attrib;

#ifdef _WIN64

  __int64       handle= -1;

#else

  long    handle= -1;

#endif

  DBUG_ENTER("my_dir");

  DBUG_PRINT("my",("path: '%s' MyFlags: %d",path,(int)MyFlags));

  /* Put LIB-CHAR as last path-character if not there */

  tmp_file=tmp_path;

  if (!*path)

    *tmp_file++ ='.';       /* From current dir */

  tmp_file= strnmov(tmp_file, path, FN_REFLEN-5);

  if (tmp_file[-1] == FN_DEVCHAR)

    *tmp_file++= '.';       /* From current dev-dir */

  if (tmp_file[-1] != FN_LIBCHAR)

    *tmp_file++ =FN_LIBCHAR;

  tmp_file[0]='*';        /* Windows needs this !??? */

  tmp_file[1]='.';

  tmp_file[2]='*';

  tmp_file[3]='\0';

  if (!(dirh= my_malloc(PSI_INSTRUMENT_ME, sizeof(*dirh), MyFlags | MY_ZEROFILL)))

    goto error;

  if (my_init_dynamic_array(PSI_INSTRUMENT_ME, &dirh->array, sizeof(FILEINFO),

                            ENTRIES_START_SIZE, ENTRIES_INCREMENT,

                            MYF(MyFlags)))

    goto error;

  init_alloc_root(PSI_INSTRUMENT_ME, &dirh->root, NAMES_START_SIZE, NAMES_START_SIZE,

                  MYF(MyFlags));

  if ((handle=_findfirst(tmp_path,&find)) == -1L)

  {

    DBUG_PRINT("info", ("findfirst returned error, errno: %d", errno));

    if  (errno != EINVAL)

      goto error;

    /*

      Could not read the directory, no read access.

      Probably because by "chmod -r".

      continue and return zero files in dir

    */

  }

  else

  {

    do

    {

      attrib= find.attrib;

      /*

        Do not show hidden and system files which Windows sometimes create.

        Note. Because Borland's findfirst() is called with the third

        argument = 0 hidden/system files are excluded from the search.

      */

      if (attrib & (_A_HIDDEN | _A_SYSTEM))

        continue;

      if (find.name[0] == '.' &&

          (find.name[1] == '\0' ||

           (find.name[1] == '.' && find.name[2] == '\0')))

        continue;                               /* . or .. */

      if (!(finfo.name= strdup_root(&dirh->root, find.name)))

        goto error;

      if (MyFlags & MY_WANT_STAT)

      {

        if (!(finfo.mystat= (MY_STAT*)alloc_root(&dirh->root, sizeof(MY_STAT))))

          goto error;

        bzero(finfo.mystat, sizeof(MY_STAT));

        finfo.mystat->st_size=find.size;

        mode= MY_S_IREAD;

        if (!(attrib & _A_RDONLY))

          mode|= MY_S_IWRITE;

        if (attrib & _A_SUBDIR)

          mode|= MY_S_IFDIR;

        finfo.mystat->st_mode= mode;

        finfo.mystat->st_mtime= ((uint32) find.time_write);

      }

      else

        finfo.mystat= NULL;

      if (push_dynamic(&dirh->array, (uchar*)&finfo))

        goto error;

    }

    while (_findnext(handle,&find) == 0);

    _findclose(handle);

  }

  if (MyFlags & MY_WANT_SORT)

    sort_dynamic(&dirh->array, (qsort_cmp) comp_names);

  dirh->dir.dir_entry= dynamic_element(&dirh->array, 0, FILEINFO *);

  dirh->dir.number_of_files= dirh->array.elements;

  DBUG_PRINT("exit", ("found %d files", dirh->dir.number_of_files));

  DBUG_RETURN(&dirh->dir);

error:

  my_errno=errno;

  if (handle != -1)

      _findclose(handle);

  my_dirend(&dirh->dir);

  if (MyFlags & (MY_FAE | MY_WME))

    my_error(EE_DIR,MYF(ME_BELL), path, errno);

  DBUG_RETURN(NULL);

} /* my_dir */

#endif /* _WIN32 */

/****************************************************************************

** File status

** Note that MY_STAT is assumed to be same as struct stat

****************************************************************************/ 

int my_fstat(File Filedes, MY_STAT *stat_area,

             myf MyFlags __attribute__((unused)))

{

  DBUG_ENTER("my_fstat");

  DBUG_PRINT("my",("fd: %d  MyFlags: %lu", Filedes, MyFlags));

#ifdef _WIN32

  DBUG_RETURN(my_win_fstat(Filedes, stat_area));

#elif defined HAVE_valgrind

  {

    int s= fstat(Filedes, stat_area);

    if (!s)

      MSAN_STAT_WORKAROUND(stat_area);

    DBUG_RETURN(s);

  }

#else

  DBUG_RETURN(fstat(Filedes, (struct stat *) stat_area));

#endif

}

MY_STAT *my_stat(const char *path, MY_STAT *stat_area, myf my_flags)

{

  int m_used;

  DBUG_ENTER("my_stat");

  DBUG_PRINT("my", ("path: '%s'  stat_area: %p  MyFlags: %lu", path,

                    stat_area, my_flags));

  if ((m_used= (stat_area == NULL)))

    if (!(stat_area= (MY_STAT *) my_malloc(key_memory_MY_STAT, sizeof(MY_STAT),

                                           my_flags)))

      goto error;

#ifndef _WIN32

  if (!stat((char *) path, (struct stat *) stat_area))

  {

    MSAN_STAT_WORKAROUND(stat_area);

    DBUG_RETURN(stat_area);

  }

#else

  if (!my_win_stat(path, stat_area))

    DBUG_RETURN(stat_area);

#endif

  DBUG_PRINT("error",("Got errno: %d from stat", errno));

  my_errno= errno;

  if (m_used)         /* Free if new area */

    my_free(stat_area);

error:

  if (my_flags & (MY_FAE+MY_WME))

  {

    my_error(EE_STAT, MYF(ME_BELL), path, my_errno);

    DBUG_RETURN((MY_STAT *) NULL);

  }

  DBUG_RETURN((MY_STAT *) NULL);

} /* my_stat */