changeset 6271:fdd622fe6d47

* mkdir-p.c (ENOSYS): Define to EEXIST if not defined. (make_dir_parents): Treat ENOSYS like EEXIST. Improve quality of diagnostics on restore_cwd failure. * mkdir-p.h (make_dir): Remove. All uses replaced by mkdir. (make_dir_parents): Last arg is now int * (for errno), not bool *. * mkdir-p.c (make_dir, make_dir_parents): Likewise. Rewrite "mkdir -p" algorithm to avoid the need for "stat" each time through the loop. Do not diagnose restore_cwd failure; that is the caller's job (and perhaps the caller does not care). * mkdir-p.c (CLEANUP_CWD, CLEANUP): Remove. (make_dir_parents): Revamp to avoid need for CLEANUP_CWD, CLEANUP. If the file already exists but is not a directory, don't bother to try to make its parents. Close potential file descriptor leak if we can't chdir("/") (!). Don't always return true if chdir($PWD) fails; return true only if the requested action was done successfully (except for the chdir($PWD)). Don't log final directory unless we actually made it. Refactor to avoid duplicate code to fix up permissions. Don't attempt to fix up parent permissions if chdir($PWD) fails. * mkdir-p.c (make_dir_parents): Don't let a failed chdir($PWD) stop us from restricting permissions of just-created absolute-named directories. * mkdir-p.c (CLEANUP_CWD): Return *true*, not false when failing to restore initial working directory. * mkdir-p.c (make_dir_parents): New parameter: different_working_dir, to tell caller if/when we change the working directory and are unable to return to the initial one. * mkdir-p.h (make_dir_parents): Update prototype. * mkdir-p.c (CLEANUP_CWD): Change one more `return 1' to `return false'. This fixes a bug introduced on 2004-07-30. Assume HAVE_UNISTD_H, i.e., include <unistd.h> unconditionally. Assume HAVE_FCNTL_H (i.e., include <fcntl.h> unconditionally, and don't include <sys/file.h>).
author Paul Eggert <eggert@cs.ucla.edu>
date Thu, 22 Sep 2005 23:24:03 +0000
parents dadc9a17b3bb
children 3baa574549ae
files lib/mkdir-p.c lib/mkdir-p.h m4/mkdir-p.m4
diffstat 3 files changed, 118 insertions(+), 183 deletions(-) [+]
line wrap: on
line diff
--- a/lib/mkdir-p.c
+++ b/lib/mkdir-p.c
@@ -30,9 +30,7 @@
 #include <stdio.h>
 #include <sys/types.h>
 #include <sys/stat.h>
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#endif
+#include <unistd.h>
 
 #include <stdlib.h>
 #include <errno.h>
@@ -47,89 +45,11 @@
 #include "quote.h"
 #include "stat-macros.h"
 
-#define WX_USR (S_IWUSR | S_IXUSR)
-
-#define CLEANUP_CWD					\
-  do							\
-    {							\
-      /* We're done operating on basename_dir.		\
-	 Restore working directory.  */			\
-      if (do_chdir)					\
-	{						\
-	  if (restore_cwd (&cwd) != 0)			\
-	    {						\
-	      int _saved_errno = errno;			\
-	      error (0, errno,				\
-		_("failed to return to initial working directory")); \
-	      free_cwd (&cwd);				\
-	      errno = _saved_errno;			\
-	      return 1;					\
-	    }						\
-	  free_cwd (&cwd);				\
-	}						\
-    }							\
-  while (0)
-
-#define CLEANUP						\
-  do							\
-    {							\
-      umask (oldmask);					\
-      CLEANUP_CWD;					\
-    }							\
-  while (0)
-
-/* Attempt to create directory DIR (aka FULLDIR) with the specified MODE.
-   If CREATED_DIR_P is non-NULL, set *CREATED_DIR_P if this
-   function creates DIR and clear it otherwise.  Give a diagnostic and
-   return false if DIR cannot be created or cannot be determined to
-   exist already.  Use FULLDIR in any diagnostic, not DIR.
-   Note that if DIR already exists, this function returns true
-   (indicating success) and clears *CREATED_DIR_P.  */
+#ifndef ENOSYS
+# define ENOSYS EEXIST
+#endif
 
-bool
-make_dir (char const *dir, char const *fulldir, mode_t mode,
-	  bool *created_dir_p)
-{
-  bool ok = true;
-  bool created_dir;
-
-  created_dir = (mkdir (dir, mode) == 0);
-
-  if (!created_dir)
-    {
-      struct stat stats;
-      int saved_errno = errno;
-
-      /* The mkdir and stat calls below may appear to be reversed.
-	 They are not.  It is important to call mkdir first and then to
-	 call stat (to distinguish the three cases) only if mkdir fails.
-	 The alternative to this approach is to `stat' each directory,
-	 then to call mkdir if it doesn't exist.  But if some other process
-	 were to create the directory between the stat & mkdir, the mkdir
-	 would fail with EEXIST.  */
-
-      if (stat (dir, &stats))
-	{
-	  error (0, saved_errno, _("cannot create directory %s"),
-		 quote (fulldir));
-	  ok = false;
-	}
-      else if (!S_ISDIR (stats.st_mode))
-	{
-	  error (0, 0, _("%s exists but is not a directory"), quote (fulldir));
-	  ok = false;
-	}
-      else
-	{
-	  /* DIR (aka FULLDIR) already exists and is a directory. */
-	}
-    }
-
-  if (created_dir_p)
-    *created_dir_p = created_dir;
-
-  return ok;
-}
+#define WX_USR (S_IWUSR | S_IXUSR)
 
 /* Ensure that the directory ARG exists.
 
@@ -145,8 +65,14 @@
    If PRESERVE_EXISTING is true and ARG is an existing directory,
    then do not attempt to set its permissions and ownership.
 
-   Return true iff ARG exists as a directory with the proper
-   ownership and permissions when done.  */
+   Set *CWD_ERRNO to a (nonzero) error number if this
+   function has changed the current working directory and is unable to
+   restore it to its initial state.  Do not change
+   *CWD_ERRNO otherwise.
+
+   Return true iff ARG exists as a directory with the proper ownership
+   and permissions when done.  Note that this function returns true
+   even when it fails to return to the initial working directory.  */
 
 bool
 make_dir_parents (char const *arg,
@@ -155,24 +81,45 @@
 		  uid_t owner,
 		  gid_t group,
 		  bool preserve_existing,
-		  char const *verbose_fmt_string)
+		  char const *verbose_fmt_string,
+		  int *cwd_errno)
 {
   struct stat stats;
   bool retval = true;
+  bool do_chdir = false;	/* Whether to chdir before each mkdir.  */
+  struct saved_cwd cwd;
+  bool cwd_problem = false;
+  char const *fixup_permissions_dir = NULL;
+  char const *full_dir = arg;
 
-  if (stat (arg, &stats) != 0)
+  struct ptr_list
+  {
+    char *dirname_end;
+    struct ptr_list *next;
+  };
+  struct ptr_list *leading_dirs = NULL;
+
+  if (stat (arg, &stats) == 0)
+    {
+      if (! S_ISDIR (stats.st_mode))
+	{
+	  error (0, 0, _("%s exists but is not a directory"), quote (arg));
+	  return false;
+	}
+
+      if (!preserve_existing)
+	fixup_permissions_dir = arg;
+    }
+  else if (errno != ENOENT || !*arg)
+    {
+      error (0, errno, "%s", quote (arg));
+      return false;
+    }
+  else
     {
       char *slash;
       mode_t tmp_mode;		/* Initial perms for leading dirs.  */
       bool re_protect;		/* Should leading dirs be unwritable? */
-      struct ptr_list
-      {
-	char *dirname_end;
-	struct ptr_list *next;
-      };
-      struct ptr_list *p, *leading_dirs = NULL;
-      bool do_chdir;		/* Whether to chdir before each mkdir.  */
-      struct saved_cwd cwd;
       char *basename_dir;
       char *dir;
 
@@ -183,6 +130,7 @@
       dir = (char *) alloca (strlen (arg) + 1);
       strcpy (dir, arg);
       strip_trailing_slashes (dir);
+      full_dir = dir;
 
       /* If leading directories shouldn't be writable or executable,
 	 or should have set[ug]id or sticky bits set and we are setting
@@ -213,7 +161,10 @@
 	     file name starts with exactly two slashes.  */
 	  char const *root = "//" + (dir[1] != '/' || dir[2] == '/');
 	  if (chdir (root) != 0)
-	    do_chdir = false;
+	    {
+	      free_cwd (&cwd);
+	      do_chdir = false;
+	    }
 	}
 
       slash = dir;
@@ -222,10 +173,8 @@
       while (*slash == '/')
 	slash++;
 
-      while (1)
+      while (true)
 	{
-	  bool newly_created_dir;
-
 	  /* slash points to the leftmost unprocessed component of dir.  */
 	  basename_dir = slash;
 
@@ -239,13 +188,7 @@
 	    basename_dir = dir;
 
 	  *slash = '\0';
-	  if (! make_dir (basename_dir, dir, tmp_mode, &newly_created_dir))
-	    {
-	      CLEANUP;
-	      return false;
-	    }
-
-	  if (newly_created_dir)
+	  if (mkdir (basename_dir, tmp_mode) == 0)
 	    {
 	      if (verbose_fmt_string)
 		error (0, 0, verbose_fmt_string, quote (dir));
@@ -259,8 +202,8 @@
 		{
 		  error (0, errno, _("cannot change owner and/or group of %s"),
 			 quote (dir));
-		  CLEANUP;
-		  return false;
+		  retval = false;
+		  break;
 		}
 
 	      if (re_protect)
@@ -272,22 +215,37 @@
 		  leading_dirs = new;
 		}
 	    }
+	  else if (errno == EEXIST || errno == ENOSYS)
+	    {
+	      /* A file is already there.  Perhaps it is a directory.
+		 If not, it will be diagnosed later.
+
+		 The ENOSYS is for Solaris 8 NFS clients, which can
+		 fail with errno == ENOSYS if mkdir is invoked on an
+		 NFS mount point.  */
+	    }
+	  else
+	    {
+	      error (0, errno, _("cannot create directory %s"), quote (dir));
+	      retval = false;
+	      break;
+	    }
 
 	  /* If we were able to save the initial working directory,
 	     then we can use chdir to change into each directory before
 	     creating an entry in that directory.  This avoids making
-	     stat and mkdir process O(n^2) file name components.  */
+	     mkdir process O(n^2) file name components.  */
 	  if (do_chdir && chdir (basename_dir) < 0)
 	    {
 	      error (0, errno, _("cannot chdir to directory %s"),
 		     quote (dir));
-	      CLEANUP;
-	      return false;
+	      retval = false;
+	      break;
 	    }
 
 	  *slash++ = '/';
 
-	  /* Avoid unnecessary calls to `stat' when given
+	  /* Avoid unnecessary calls to mkdir when given
 	     file names containing multiple adjacent slashes.  */
 	  while (*slash == '/')
 	    slash++;
@@ -301,26 +259,40 @@
 
       /* We're done making leading directories.
 	 Create the final component of the file name.  */
-
-      if (! make_dir (basename_dir, dir, mode, NULL))
+      if (retval)
 	{
-	  CLEANUP;
-	  return false;
+	  if (mkdir (basename_dir, mode) != 0)
+	    {
+	      error (0, errno, _("cannot create directory %s"), quote (dir));
+	      retval = false;
+	    }
+	  else
+	    {
+	      if (verbose_fmt_string)
+		error (0, 0, verbose_fmt_string, quote (dir));
+	      fixup_permissions_dir = basename_dir;
+	    }
 	}
+    }
 
-      if (verbose_fmt_string != NULL)
-	error (0, 0, verbose_fmt_string, quote (dir));
+  if (fixup_permissions_dir)
+    {
+      /* chown must precede chmod because on some systems,
+	 chown clears the set[ug]id bits for non-superusers,
+	 resulting in incorrect permissions.
+	 On System V, users can give away files with chown and then not
+	 be able to chmod them.  So don't give files away.  */
 
       if (owner != (uid_t) -1 || group != (gid_t) -1)
 	{
-	  if (chown (basename_dir, owner, group)
+	  if (chown (fixup_permissions_dir, owner, group) != 0
 #ifdef AFS
 	      && errno != EPERM
 #endif
 	      )
 	    {
 	      error (0, errno, _("cannot change owner and/or group of %s"),
-		     quote (dir));
+		     quote (full_dir));
 	      retval = false;
 	    }
 	}
@@ -330,67 +302,35 @@
 	 required to honor only the file permission bits.  In particular,
 	 it need not honor the `special' bits, so if MODE includes any
 	 special bits, set them here.  */
-      if ((mode & ~S_IRWXUGO)
-	  && chmod (basename_dir, mode))
+      if ((mode & ~S_IRWXUGO) && chmod (fixup_permissions_dir, mode) != 0)
 	{
 	  error (0, errno, _("cannot change permissions of %s"),
-		 quote (dir));
+		 quote (full_dir));
 	  retval = false;
 	}
-
-      CLEANUP_CWD;
-
-      /* If the mode for leading directories didn't include owner "wx"
-	 privileges, we have to reset their protections to the correct
-	 value.  */
-      for (p = leading_dirs; p != NULL; p = p->next)
-	{
-	  *(p->dirname_end) = '\0';
-	  if (chmod (dir, parent_mode) != 0)
-	    {
-	      error (0, errno, _("cannot change permissions of %s"),
-		     quote (dir));
-	      retval = false;
-	    }
-	}
     }
-  else
+
+  if (do_chdir)
     {
-      /* We get here if the file already exists.  */
-
-      char const *dir = arg;
-
-      if (!S_ISDIR (stats.st_mode))
-	{
-	  error (0, 0, _("%s exists but is not a directory"), quote (dir));
-	  return false;
-	}
-
-      if (!preserve_existing)
+      if (restore_cwd (&cwd) != 0)
 	{
-	  /* chown must precede chmod because on some systems,
-	     chown clears the set[ug]id bits for non-superusers,
-	     resulting in incorrect permissions.
-	     On System V, users can give away files with chown and then not
-	     be able to chmod them.  So don't give files away.  */
+	  *cwd_errno = errno;
+	  cwd_problem = true;
+	}
+      free_cwd (&cwd);
+    }
 
-	  if ((owner != (uid_t) -1 || group != (gid_t) -1)
-	      && chown (dir, owner, group)
-#ifdef AFS
-	      && errno != EPERM
-#endif
-	      )
-	    {
-	      error (0, errno, _("cannot change owner and/or group of %s"),
-		     quote (dir));
-	      retval = false;
-	    }
-	  if (chmod (dir, mode) != 0)
-	    {
-	      error (0, errno, _("cannot change permissions of %s"),
-				 quote (dir));
-	      retval = false;
-	    }
+  /* If the mode for leading directories didn't include owner "wx"
+     privileges, reset their protections to the correct value.  */
+  for (; leading_dirs != NULL; leading_dirs = leading_dirs->next)
+    {
+      leading_dirs->dirname_end[0] = '\0';
+      if ((cwd_problem && *full_dir != '/')
+	  || chmod (full_dir, parent_mode) != 0)
+	{
+	  error (0, (cwd_problem ? 0 : errno),
+		 _("cannot change permissions of %s"), quote (full_dir));
+	  retval = false;
 	}
     }
 
--- a/lib/mkdir-p.h
+++ b/lib/mkdir-p.h
@@ -28,9 +28,5 @@
 		       uid_t owner,
 		       gid_t group,
 		       bool preserve_existing,
-		       char const *verbose_fmt_string);
-
-bool make_dir (char const *dir,
-	       char const *fulldir,
-	       mode_t mode,
-	       bool *created_dir_p);
+		       char const *verbose_fmt_string,
+		       int *cwd_errno);
--- a/m4/mkdir-p.m4
+++ b/m4/mkdir-p.m4
@@ -1,4 +1,4 @@
-# mkdir-p.m4 serial 8
+# mkdir-p.m4 serial 9
 dnl Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -11,6 +11,5 @@
 
   dnl Prerequisites of lib/mkdir-p.c.
   AC_REQUIRE([AC_FUNC_ALLOCA])
-  AC_CHECK_HEADERS_ONCE(unistd.h)
   AC_REQUIRE([gl_AFS])
 ])