src/port/dirent.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * dirent.c
   4  *        opendir/readdir/closedir for win32/msvc
   5  *
   6  * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  *
  10  * IDENTIFICATION
  11  *        src/port/dirent.c
  12  *
  13  *-------------------------------------------------------------------------
  14  */
  15
  16 #ifndef FRONTEND
  17 #include "postgres.h"
  18 #else
  19 #include "postgres_fe.h"
  20 #endif
  21
  22 #include <dirent.h>
  23
  24
  25 struct DIR
  26 {
  27         char       *dirname;
  28         struct dirent ret;                      /* Used to return to caller */
  29         HANDLE          handle;
  30 };
  31
  32 DIR *
  33 opendir(const char *dirname)
  34 {
  35         DWORD           attr;
  36         DIR                *d;
  37
  38         /* Make sure it is a directory */
  39         attr = GetFileAttributes(dirname);
  40         if (attr == INVALID_FILE_ATTRIBUTES)
  41         {
  42                 errno = ENOENT;
  43                 return NULL;
  44         }
  45         if ((attr & FILE_ATTRIBUTE_DIRECTORY) != FILE_ATTRIBUTE_DIRECTORY)
  46         {
  47                 errno = ENOTDIR;
  48                 return NULL;
  49         }
  50
  51         d = malloc(sizeof(DIR));
  52         if (!d)
  53         {
  54                 errno = ENOMEM;
  55                 return NULL;
  56         }
  57         d->dirname = malloc(strlen(dirname) + 4);
  58         if (!d->dirname)
  59         {
  60                 errno = ENOMEM;
  61                 free(d);
  62                 return NULL;
  63         }
  64         strcpy(d->dirname, dirname);
  65         if (d->dirname[strlen(d->dirname) - 1] != '/' &&
  66                 d->dirname[strlen(d->dirname) - 1] != '\\')
  67                 strcat(d->dirname, "\\");       /* Append backslash if not already there */
  68         strcat(d->dirname, "*");        /* Search for entries named anything */
  69         d->handle = INVALID_HANDLE_VALUE;
  70         d->ret.d_ino = 0;                       /* no inodes on win32 */
  71         d->ret.d_reclen = 0;            /* not used on win32 */
  72         d->ret.d_type = DT_UNKNOWN;
  73
  74         return d;
  75 }
  76
  77 struct dirent *
  78 readdir(DIR *d)
  79 {
  80         WIN32_FIND_DATA fd;
  81
  82         if (d->handle == INVALID_HANDLE_VALUE)
  83         {
  84                 d->handle = FindFirstFile(d->dirname, &fd);
  85                 if (d->handle == INVALID_HANDLE_VALUE)
  86                 {
  87                         /* If there are no files, force errno=0 (unlike mingw) */
  88                         if (GetLastError() == ERROR_FILE_NOT_FOUND)
  89                                 errno = 0;
  90                         else
  91                                 _dosmaperr(GetLastError());
  92                         return NULL;
  93                 }
  94         }
  95         else
  96         {
  97                 if (!FindNextFile(d->handle, &fd))
  98                 {
  99                         /* If there are no more files, force errno=0 (like mingw) */
 100                         if (GetLastError() == ERROR_NO_MORE_FILES)
 101                                 errno = 0;
 102                         else
 103                                 _dosmaperr(GetLastError());
 104                         return NULL;
 105                 }
 106         }
 107         strcpy(d->ret.d_name, fd.cFileName);    /* Both strings are MAX_PATH long */
 108         d->ret.d_namlen = strlen(d->ret.d_name);
 109         /* The only identified types are: directory, regular file or symbolic link */
 110         if ((fd.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0)
 111                 d->ret.d_type = DT_DIR;
 112         /* For reparse points dwReserved0 field will contain the ReparseTag */
 113         else if ((fd.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) != 0 &&
 114                          (fd.dwReserved0 == IO_REPARSE_TAG_MOUNT_POINT))
 115                 d->ret.d_type = DT_LNK;
 116         else
 117                 d->ret.d_type = DT_REG;
 118
 119         return &d->ret;
 120 }
 121
 122 int
 123 closedir(DIR *d)
 124 {
 125         int                     ret = 0;
 126
 127         if (d->handle != INVALID_HANDLE_VALUE)
 128                 ret = !FindClose(d->handle);
 129         free(d->dirname);
 130         free(d);
 131
 132         return ret;
 133 }