merge with mainline

kern/emu/getroot.c

@@ -22,8 +22,10 @@
 #include <unistd.h>
 #include <string.h>
 #include <dirent.h>
+#include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdint.h>
 
 #ifdef __CYGWIN__
 # include <sys/fcntl.h>
@@ -83,103 +85,6 @@ xgetcwd (void)
   return path;
 }
 
-#ifdef __CYGWIN__
-/* Convert POSIX path to Win32 path,
-   remove drive letter, replace backslashes.  */
-static char *
-get_win32_path (const char *path)
-{
-  char winpath[PATH_MAX];
-  cygwin_conv_to_full_win32_path (path, winpath);
-
-  int len = strlen (winpath);
-  if (len > 2 && winpath[1] == ':')
-    {
-      len -= 2;
-      memmove (winpath, winpath + 2, len + 1);
-    }
-
-  int i;
-  for (i = 0; i < len; i++)
-    if (winpath[i] == '\\')
-      winpath[i] = '/';
-  return xstrdup (winpath);
-}
-#endif
-
-char *
-grub_get_prefix (const char *dir)
-{
-  char *saved_cwd;
-  char *abs_dir, *prev_dir;
-  char *prefix;
-  struct stat st, prev_st;
-
-  /* Save the current directory.  */
-  saved_cwd = xgetcwd ();
-
-  if (chdir (dir) < 0)
-    grub_util_error ("cannot change directory to `%s'", dir);
-
-  abs_dir = xgetcwd ();
-  strip_extra_slashes (abs_dir);
-  prev_dir = xstrdup (abs_dir);
-
-  if (stat (".", &prev_st) < 0)
-    grub_util_error ("cannot stat `%s'", dir);
-
-  if (! S_ISDIR (prev_st.st_mode))
-    grub_util_error ("`%s' is not a directory", dir);
-
-  while (1)
-    {
-      if (chdir ("..") < 0)
-	grub_util_error ("cannot change directory to the parent");
-
-      if (stat (".", &st) < 0)
-	grub_util_error ("cannot stat current directory");
-
-      if (! S_ISDIR (st.st_mode))
-	grub_util_error ("current directory is not a directory???");
-
-      if (prev_st.st_dev != st.st_dev || prev_st.st_ino == st.st_ino)
-	break;
-
-      free (prev_dir);
-      prev_dir = xgetcwd ();
-      prev_st = st;
-    }
-
-  strip_extra_slashes (prev_dir);
-  prefix = xmalloc (strlen (abs_dir) - strlen (prev_dir) + 2);
-  prefix[0] = '/';
-  strcpy (prefix + 1, abs_dir + strlen (prev_dir));
-  strip_extra_slashes (prefix);
-
-  if (chdir (saved_cwd) < 0)
-    grub_util_error ("cannot change directory to `%s'", dir);
-
-#ifdef __CYGWIN__
-  if (st.st_dev != (DEV_CYGDRIVE_MAJOR << 16))
-    {
-      /* Reached some mount point not below /cygdrive.
-	 GRUB does not know Cygwin's emulated mounts,
-	 convert to Win32 path.  */
-      grub_util_info ("Cygwin prefix = %s", prefix);
-      char * wprefix = get_win32_path (prefix);
-      free (prefix);
-      prefix = wprefix;
-    }
-#endif
-
-  free (saved_cwd);
-  free (abs_dir);
-  free (prev_dir);
-
-  grub_util_info ("prefix = %s", prefix);
-  return prefix;
-}
-
 #ifdef __MINGW32__
 
 static char *
@@ -641,4 +546,3 @@ grub_util_check_char_device (const char *blk_dev)
   else
     return 0;
 }
-

kern/emu/main.c

@@ -246,7 +246,7 @@ main (int argc, char *argv[])
   if (strcmp (root_dev, "host") == 0)
     dir = xstrdup (dir);
   else
-    dir = grub_get_prefix (dir);
+    dir = grub_make_system_path_relative_to_its_root (dir);
   prefix = xmalloc (strlen (root_dev) + 2 + strlen (dir) + 1);
   sprintf (prefix, "(%s)%s", root_dev, dir);
   free (dir);

kern/emu/misc.c

@@ -3,8 +3,12 @@
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdint.h>
 #include <string.h>
 #include <sys/time.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
 
 #include <grub/mm.h>
 #include <grub/err.h>
@@ -171,3 +175,102 @@ grub_get_rtc (void)
 	  + (((tv.tv_sec % GRUB_TICKS_PER_SECOND) * 1000000 + tv.tv_usec)
 	     * GRUB_TICKS_PER_SECOND / 1000000));
 }
+
+
+/* This function never prints trailing slashes (so that its output
+   can be appended a slash unconditionally).  */
+char *
+grub_make_system_path_relative_to_its_root (const char *path)
+{
+  struct stat st;
+  char *p, *buf, *buf2, *buf3;
+  uintptr_t offset = 0;
+  dev_t num;
+  size_t len;
+
+  /* canonicalize.  */
+  p = canonicalize_file_name (path);
+
+  if (p == NULL)
+    grub_util_error ("failed to get canonical path of %s", path);
+
+  len = strlen (p) + 1;
+  buf = xstrdup (p);
+  free (p);
+
+  if (stat (buf, &st) < 0)
+    grub_util_error ("cannot stat %s: %s", buf, strerror (errno));
+
+  buf2 = xstrdup (buf);
+  num = st.st_dev;
+
+  /* This loop sets offset to the number of chars of the root
+     directory we're inspecting.  */
+  while (1)
+    {
+      p = strrchr (buf, '/');
+      if (p == NULL)
+	/* This should never happen.  */
+	grub_util_error ("FIXME: no / in buf. (make_system_path_relative_to_its_root)");
+      if (p != buf)
+	*p = 0;
+      else
+	*++p = 0;
+
+      if (stat (buf, &st) < 0)
+	grub_util_error ("cannot stat %s: %s", buf, strerror (errno));
+
+      /* buf is another filesystem; we found it.  */
+      if (st.st_dev != num)
+	{
+	  /* offset == 0 means path given is the mount point.
+	     This works around special-casing of "/" in Un*x.  This function never
+	     prints trailing slashes (so that its output can be appended a slash
+	     unconditionally).  Each slash in is considered a preceding slash, and
+	     therefore the root directory is an empty string.  */
+	  if (offset == 0)
+	    {
+	      free (buf);
+	      free (buf2);
+	      return xstrdup ("");
+	    }
+	  else
+	    break;
+	}
+
+      offset = p - buf;
+      /* offset == 1 means root directory.  */
+      if (offset == 1)
+	{
+	  /* Include leading slash.  */
+	  offset = 0;
+	  break;
+	}
+    }
+  free (buf);
+  buf3 = xstrdup (buf2 + offset);
+  free (buf2);
+
+#ifdef __CYGWIN__
+  if (st.st_dev != (DEV_CYGDRIVE_MAJOR << 16))
+    {
+      /* Reached some mount point not below /cygdrive.
+	 GRUB does not know Cygwin's emulated mounts,
+	 convert to Win32 path.  */
+      grub_util_info ("Cygwin path = %s\n", buf3);
+      char * temp = get_win32_path (buf3);
+      free (buf3);
+      buf3 = temp;
+    }
+#endif
+
+  /* Remove trailing slashes, return empty string if root directory.  */
+  len = strlen (buf3);
+  while (len > 0 && buf3[len - 1] == '/')
+    {
+      buf3[len - 1] = '\0';
+      len--;
+    }
+
+  return buf3;
+}