Path-mangling logic was failing to account for paths containing mentions

of '.' or '..'.  Extend canonicalize_path() to trim off trailing occurrences
of these things, and use it to fix up paths where needed (which I think is
only after places where we trim the last path component, but maybe some
others will turn up).  Fixes Josh's complaint that './initdb' does not
work.

src/bin/initdb/initdb.c

@@ -39,7 +39,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  * Portions taken from FreeBSD.
  *
- * $PostgreSQL: pgsql/src/bin/initdb/initdb.c,v 1.46 2004/08/01 06:19:23 momjian Exp $
+ * $PostgreSQL: pgsql/src/bin/initdb/initdb.c,v 1.47 2004/08/09 20:20:47 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -2227,6 +2227,7 @@ main(int argc, char *argv[])
 	/* store binary directory */
 	strcpy(bin_path, backend_exec);
 	*last_dir_separator(bin_path) = '\0';
+	canonicalize_path(bin_path);
 
 	if (!share_path)
 	{

src/port/exec.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/port/exec.c,v 1.20 2004/08/09 03:12:38 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/port/exec.c,v 1.21 2004/08/09 20:20:46 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -433,6 +433,9 @@ find_other_exec(const char *argv0, const char *target,
 
 	/* Trim off program name and keep just directory */	
 	*last_dir_separator(retpath) = '\0';
+	canonicalize_path(retpath);
+
+	/* Now append the other program's name */
 	snprintf(retpath + strlen(retpath), MAXPGPATH - strlen(retpath),
 			 "/%s%s", target, EXE);
 

src/port/path.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/port/path.c,v 1.26 2004/08/01 06:56:39 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/port/path.c,v 1.27 2004/08/09 20:20:46 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -116,11 +116,33 @@ canonicalize_path(char *path)
 #endif
 
 	/*
-	 *	Removing the trailing slash on a path means we never get
-	 *	ugly double slashes.  Don't remove a leading slash, though.
-	 *	Also, Win32 can't stat() a directory with a trailing slash.
+	 * Removing the trailing slash on a path means we never get ugly double
+	 * slashes.  Also, Win32 can't stat() a directory with a trailing slash.
+	 * Don't remove a leading slash, though.
 	 */
 	trim_trailing_separator(path);
+
+	/*
+	 * Remove any trailing uses of "." or "..", too.
+	 */
+	for (;;)
+	{
+		int		len = strlen(path);
+
+		if (len >= 2 && strcmp(path + len - 2, "/.") == 0)
+		{
+			trim_directory(path);
+			trim_trailing_separator(path);
+		}
+		else if (len >= 3 && strcmp(path + len - 3, "/..") == 0)
+		{
+			trim_directory(path);
+			trim_directory(path);
+			trim_trailing_separator(path);
+		}
+		else
+			break;
+	}
 }
 
 
@@ -444,7 +466,7 @@ trim_trailing_separator(char *path)
 #ifdef WIN32
 	/*
 	 *	Skip over network and drive specifiers for win32.
-	 *	Set 'path' to point to the last character to keep.
+	 *	Set 'path' to point to the last character we must keep.
 	 */
     if (strlen(path) >= 2)
     {