X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Flink.c;h=c1ec41c34054e548dca3f6c0a221374fefedc547;hb=25b6b5120113989e0b91de9d0b75d3d625bbc753;hp=6737d37e9d7cc7bde589611f1ccd0a7a91874df1;hpb=d1ed8a817f5d07d4013cfa0988ee2da8b2937db6;p=gnulib.git
diff --git a/lib/link.c b/lib/link.c
index 6737d37e9..c1ec41c34 100644
--- a/lib/link.c
+++ b/lib/link.c
@@ -1,6 +1,6 @@
/* Emulate link on platforms that lack it, namely native Windows platforms.
- Copyright (C) 2009 Free Software Foundation, Inc.
+ Copyright (C) 2009-2012 Free Software Foundation, Inc.
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
@@ -13,71 +13,199 @@
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 02110-1301, USA. */
+ along with this program; if not, see . */
#include
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
-
-#define WIN32_LEAN_AND_MEAN
-#define _WIN32_WINNT 0x0500
#include
-#include
#include
+#include
+#include
+#include
+
+#if !HAVE_LINK
+# if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+
+# define WIN32_LEAN_AND_MEAN
+# include
+
+/* CreateHardLink was introduced only in Windows 2000. */
+typedef BOOL (WINAPI * CreateHardLinkFuncType) (LPCTSTR lpFileName,
+ LPCTSTR lpExistingFileName,
+ LPSECURITY_ATTRIBUTES lpSecurityAttributes);
+static CreateHardLinkFuncType CreateHardLinkFunc = NULL;
+static BOOL initialized = FALSE;
+
+static void
+initialize (void)
+{
+ HMODULE kernel32 = GetModuleHandle ("kernel32.dll");
+ if (kernel32 != NULL)
+ {
+ CreateHardLinkFunc =
+ (CreateHardLinkFuncType) GetProcAddress (kernel32, "CreateHardLinkA");
+ }
+ initialized = TRUE;
+}
int
-link (const char *path1, const char *path2)
+link (const char *file1, const char *file2)
{
- if (CreateHardLink (path2, path1, NULL) == 0)
+ char *dir;
+ size_t len1 = strlen (file1);
+ size_t len2 = strlen (file2);
+ if (!initialized)
+ initialize ();
+ if (CreateHardLinkFunc == NULL)
+ {
+ /* System does not support hard links. */
+ errno = EPERM;
+ return -1;
+ }
+ /* Reject trailing slashes on non-directories; mingw does not
+ support hard-linking directories. */
+ if ((len1 && (file1[len1 - 1] == '/' || file1[len1 - 1] == '\\'))
+ || (len2 && (file2[len2 - 1] == '/' || file2[len2 - 1] == '\\')))
+ {
+ struct stat st;
+ if (stat (file1, &st) == 0 && S_ISDIR (st.st_mode))
+ errno = EPERM;
+ else
+ errno = ENOTDIR;
+ return -1;
+ }
+ /* CreateHardLink("b/.","a",NULL) creates file "b", so we must check
+ that dirname(file2) exists. */
+ dir = strdup (file2);
+ if (!dir)
+ return -1;
+ {
+ struct stat st;
+ char *p = strchr (dir, '\0');
+ while (dir < p && (*--p != '/' && *p != '\\'));
+ *p = '\0';
+ if (p != dir && stat (dir, &st) == -1)
+ {
+ int saved_errno = errno;
+ free (dir);
+ errno = saved_errno;
+ return -1;
+ }
+ free (dir);
+ }
+ /* Now create the link. */
+ if (CreateHardLinkFunc (file2, file1, NULL) == 0)
{
/* It is not documented which errors CreateHardLink() can produce.
* The following conversions are based on tests on a Windows XP SP2
* system. */
DWORD err = GetLastError ();
switch (err)
- {
- case ERROR_ACCESS_DENIED:
- errno = EACCES;
- break;
-
- case ERROR_INVALID_FUNCTION: /* fs does not support hard links */
- errno = EPERM;
- break;
-
- case ERROR_NOT_SAME_DEVICE:
- errno = EXDEV;
- break;
-
- case ERROR_PATH_NOT_FOUND:
- case ERROR_FILE_NOT_FOUND:
- errno = ENOENT;
- break;
-
- case ERROR_INVALID_PARAMETER:
- errno = ENAMETOOLONG;
- break;
-
- case ERROR_TOO_MANY_LINKS:
- errno = EMLINK;
- break;
-
- case ERROR_ALREADY_EXISTS:
- errno = EEXIST;
- break;
-
- default:
- errno = EIO;
- }
+ {
+ case ERROR_ACCESS_DENIED:
+ errno = EACCES;
+ break;
+
+ case ERROR_INVALID_FUNCTION: /* fs does not support hard links */
+ errno = EPERM;
+ break;
+
+ case ERROR_NOT_SAME_DEVICE:
+ errno = EXDEV;
+ break;
+
+ case ERROR_PATH_NOT_FOUND:
+ case ERROR_FILE_NOT_FOUND:
+ errno = ENOENT;
+ break;
+
+ case ERROR_INVALID_PARAMETER:
+ errno = ENAMETOOLONG;
+ break;
+
+ case ERROR_TOO_MANY_LINKS:
+ errno = EMLINK;
+ break;
+
+ case ERROR_ALREADY_EXISTS:
+ errno = EEXIST;
+ break;
+
+ default:
+ errno = EIO;
+ }
return -1;
}
return 0;
}
-#else /* !Windows */
+# else /* !Windows */
-#error "This platform lacks a link function, and Gnulib doesn't provide a replacement. This is a bug in Gnulib."
+# error "This platform lacks a link function, and Gnulib doesn't provide a replacement. This is a bug in Gnulib."
-#endif /* !Windows */
+# endif /* !Windows */
+#else /* HAVE_LINK */
+
+# undef link
+
+/* Create a hard link from FILE1 to FILE2, working around platform bugs. */
+int
+rpl_link (char const *file1, char const *file2)
+{
+ size_t len1;
+ size_t len2;
+ struct stat st;
+
+ /* Don't allow IRIX to dereference dangling file2 symlink. */
+ if (!lstat (file2, &st))
+ {
+ errno = EEXIST;
+ return -1;
+ }
+
+ /* Reject trailing slashes on non-directories. */
+ len1 = strlen (file1);
+ len2 = strlen (file2);
+ if ((len1 && file1[len1 - 1] == '/')
+ || (len2 && file2[len2 - 1] == '/'))
+ {
+ /* Let link() decide whether hard-linking directories is legal.
+ If stat() fails, then link() should fail for the same reason
+ (although on Solaris 9, link("file/","oops") mistakenly
+ succeeds); if stat() succeeds, require a directory. */
+ if (stat (file1, &st))
+ return -1;
+ if (!S_ISDIR (st.st_mode))
+ {
+ errno = ENOTDIR;
+ return -1;
+ }
+ }
+ else
+ {
+ /* Fix Cygwin 1.5.x bug where link("a","b/.") creates file "b". */
+ char *dir = strdup (file2);
+ char *p;
+ if (!dir)
+ return -1;
+ /* We already know file2 does not end in slash. Strip off the
+ basename, then check that the dirname exists. */
+ p = strrchr (dir, '/');
+ if (p)
+ {
+ *p = '\0';
+ if (stat (dir, &st) == -1)
+ {
+ int saved_errno = errno;
+ free (dir);
+ errno = saved_errno;
+ return -1;
+ }
+ }
+ free (dir);
+ }
+ return link (file1, file2);
+}
+#endif /* HAVE_LINK */