src/port/copydir.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * copydir.c
   4  *        copies a directory
   5  *
   6  * Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  *      While "xcopy /e /i /q" works fine for copying directories, on Windows XP
  10  *      it requires a Window handle which prevents it from working when invoked
  11  *      as a service.
  12  *
  13  * IDENTIFICATION
  14  *        $PostgreSQL$
  15  *
  16  *-------------------------------------------------------------------------
  17  */
  18
  19 #include "postgres.h"
  20
  21 #include <fcntl.h>
  22 #include <unistd.h>
  23 #include <sys/stat.h>
  24
  25 #include "storage/fd.h"
  26
  27 /*
  28  *      On Windows, call non-macro versions of palloc; we can't reference
  29  *      CurrentMemoryContext in this file because of PGDLLIMPORT conflict.
  30  */
  31 #if defined(WIN32) || defined(__CYGWIN__)
  32 #undef palloc
  33 #undef pstrdup
  34 #define palloc(sz)              pgport_palloc(sz)
  35 #define pstrdup(str)    pgport_pstrdup(str)
  36 #endif
  37
  38
  39 static void copy_file(char *fromfile, char *tofile);
  40
  41
  42 /*
  43  * copydir: copy a directory
  44  *
  45  * If recurse is false, subdirectories are ignored.  Anything that's not
  46  * a directory or a regular file is ignored.
  47  */
  48 void
  49 copydir(char *fromdir, char *todir, bool recurse)
  50 {
  51         DIR                *xldir;
  52         struct dirent *xlde;
  53         char            fromfile[MAXPGPATH];
  54         char            tofile[MAXPGPATH];
  55
  56         if (mkdir(todir, S_IRUSR | S_IWUSR | S_IXUSR) != 0)
  57                 ereport(ERROR,
  58                                 (errcode_for_file_access(),
  59                                  errmsg("could not create directory \"%s\": %m", todir)));
  60
  61         xldir = AllocateDir(fromdir);
  62         if (xldir == NULL)
  63                 ereport(ERROR,
  64                                 (errcode_for_file_access(),
  65                                  errmsg("could not open directory \"%s\": %m", fromdir)));
  66
  67         while ((xlde = ReadDir(xldir, fromdir)) != NULL)
  68         {
  69                 struct stat fst;
  70
  71                 if (strcmp(xlde->d_name, ".") == 0 ||
  72                         strcmp(xlde->d_name, "..") == 0)
  73                         continue;
  74
  75                 snprintf(fromfile, MAXPGPATH, "%s/%s", fromdir, xlde->d_name);
  76                 snprintf(tofile, MAXPGPATH, "%s/%s", todir, xlde->d_name);
  77
  78                 if (lstat(fromfile, &fst) < 0)
  79                         ereport(ERROR,
  80                                         (errcode_for_file_access(),
  81                                          errmsg("could not stat file \"%s\": %m", fromfile)));
  82
  83                 if (S_ISDIR(fst.st_mode))
  84                 {
  85                         /* recurse to handle subdirectories */
  86                         if (recurse)
  87                                 copydir(fromfile, tofile, true);
  88                 }
  89                 else if (S_ISREG(fst.st_mode))
  90                         copy_file(fromfile, tofile);
  91         }
  92
  93         FreeDir(xldir);
  94 }
  95
  96 /*
  97  * copy one file
  98  */
  99 static void
 100 copy_file(char *fromfile, char *tofile)
 101 {
 102         char       *buffer;
 103         int                     srcfd;
 104         int                     dstfd;
 105         int                     nbytes;
 106
 107         /* Use palloc to ensure we get a maxaligned buffer */
 108 #define COPY_BUF_SIZE (8 * BLCKSZ)
 109
 110         buffer = palloc(COPY_BUF_SIZE);
 111
 112         /*
 113          * Open the files
 114          */
 115         srcfd = BasicOpenFile(fromfile, O_RDONLY | PG_BINARY, 0);
 116         if (srcfd < 0)
 117                 ereport(ERROR,
 118                                 (errcode_for_file_access(),
 119                                  errmsg("could not open file \"%s\": %m", fromfile)));
 120
 121         dstfd = BasicOpenFile(tofile, O_RDWR | O_CREAT | O_EXCL | PG_BINARY,
 122                                                   S_IRUSR | S_IWUSR);
 123         if (dstfd < 0)
 124                 ereport(ERROR,
 125                                 (errcode_for_file_access(),
 126                                  errmsg("could not create file \"%s\": %m", tofile)));
 127
 128         /*
 129          * Do the data copying.
 130          */
 131         for (;;)
 132         {
 133                 nbytes = read(srcfd, buffer, COPY_BUF_SIZE);
 134                 if (nbytes < 0)
 135                         ereport(ERROR,
 136                                         (errcode_for_file_access(),
 137                                          errmsg("could not read file \"%s\": %m", fromfile)));
 138                 if (nbytes == 0)
 139                         break;
 140                 errno = 0;
 141                 if ((int) write(dstfd, buffer, nbytes) != nbytes)
 142                 {
 143                         /* if write didn't set errno, assume problem is no disk space */
 144                         if (errno == 0)
 145                                 errno = ENOSPC;
 146                         ereport(ERROR,
 147                                         (errcode_for_file_access(),
 148                                          errmsg("could not write to file \"%s\": %m", tofile)));
 149                 }
 150         }
 151
 152         /*
 153          * Be paranoid here to ensure we catch problems.
 154          */
 155         if (pg_fsync(dstfd) != 0)
 156                 ereport(ERROR,
 157                                 (errcode_for_file_access(),
 158                                  errmsg("could not fsync file \"%s\": %m", tofile)));
 159
 160         if (close(dstfd))
 161                 ereport(ERROR,
 162                                 (errcode_for_file_access(),
 163                                  errmsg("could not close file \"%s\": %m", tofile)));
 164
 165         close(srcfd);
 166
 167         pfree(buffer);
 168 }