granicus.if.org Git - postgresql/blob - src/common/rmtree.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * rmtree.c
   4  *
   5  * Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group
   6  * Portions Copyright (c) 1994, Regents of the University of California
   7  *
   8  * IDENTIFICATION
   9  *        src/common/rmtree.c
  10  *
  11  *-------------------------------------------------------------------------
  12  */
  13
  14 #ifndef FRONTEND
  15 #include "postgres.h"
  16 #else
  17 #include "postgres_fe.h"
  18 #endif
  19
  20 #include <unistd.h>
  21 #include <sys/stat.h>
  22
  23
  24 /*
  25  *      rmtree
  26  *
  27  *      Delete a directory tree recursively.
  28  *      Assumes path points to a valid directory.
  29  *      Deletes everything under path.
  30  *      If rmtopdir is true deletes the directory too.
  31  *      Returns true if successful, false if there was any problem.
  32  *      (The details of the problem are reported already, so caller
  33  *      doesn't really have to say anything more, but most do.)
  34  */
  35 bool
  36 rmtree(const char *path, bool rmtopdir)
  37 {
  38         bool            result = true;
  39         char            pathbuf[MAXPGPATH];
  40         char      **filenames;
  41         char      **filename;
  42         struct stat statbuf;
  43
  44         /*
  45          * we copy all the names out of the directory before we start modifying
  46          * it.
  47          */
  48         filenames = pgfnames(path);
  49
  50         if (filenames == NULL)
  51                 return false;
  52
  53         /* now we have the names we can start removing things */
  54         for (filename = filenames; *filename; filename++)
  55         {
  56                 snprintf(pathbuf, MAXPGPATH, "%s/%s", path, *filename);
  57
  58                 /*
  59                  * It's ok if the file is not there anymore; we were just about to
  60                  * delete it anyway.
  61                  *
  62                  * This is not an academic possibility. One scenario where this
  63                  * happens is when bgwriter has a pending unlink request for a file in
  64                  * a database that's being dropped. In dropdb(), we call
  65                  * ForgetDatabaseFsyncRequests() to flush out any such pending unlink
  66                  * requests, but because that's asynchronous, it's not guaranteed that
  67                  * the bgwriter receives the message in time.
  68                  */
  69                 if (lstat(pathbuf, &statbuf) != 0)
  70                 {
  71                         if (errno != ENOENT)
  72                         {
  73 #ifndef FRONTEND
  74                                 elog(WARNING, "could not stat file or directory \"%s\": %m",
  75                                          pathbuf);
  76 #else
  77                                 fprintf(stderr, _("could not stat file or directory \"%s\": %s\n"),
  78                                                 pathbuf, strerror(errno));
  79 #endif
  80                                 result = false;
  81                         }
  82                         continue;
  83                 }
  84
  85                 if (S_ISDIR(statbuf.st_mode))
  86                 {
  87                         /* call ourselves recursively for a directory */
  88                         if (!rmtree(pathbuf, true))
  89                         {
  90                                 /* we already reported the error */
  91                                 result = false;
  92                         }
  93                 }
  94                 else
  95                 {
  96                         if (unlink(pathbuf) != 0)
  97                         {
  98                                 if (errno != ENOENT)
  99                                 {
 100 #ifndef FRONTEND
 101                                         elog(WARNING, "could not remove file or directory \"%s\": %m",
 102                                                  pathbuf);
 103 #else
 104                                         fprintf(stderr, _("could not remove file or directory \"%s\": %s\n"),
 105                                                         pathbuf, strerror(errno));
 106 #endif
 107                                         result = false;
 108                                 }
 109                         }
 110                 }
 111         }
 112
 113         if (rmtopdir)
 114         {
 115                 if (rmdir(path) != 0)
 116                 {
 117 #ifndef FRONTEND
 118                         elog(WARNING, "could not remove file or directory \"%s\": %m",
 119                                  path);
 120 #else
 121                         fprintf(stderr, _("could not remove file or directory \"%s\": %s\n"),
 122                                         path, strerror(errno));
 123 #endif
 124                         result = false;
 125                 }
 126         }
 127
 128         pgfnames_cleanup(filenames);
 129
 130         return result;
 131 }