psql-filename-completion-fixes-1.patch

diff --git a/config/programs.m4 b/config/programs.m4
index 90ff944..e5bf980 100644
--- a/config/programs.m4
+++ b/config/programs.m4
@@ -209,11 +209,12 @@ fi
 
 
 
-# PGAC_VAR_RL_COMPLETION_APPEND_CHARACTER
-# ---------------------------------------
+# PGAC_READLINE_VARIABLES
+# -----------------------
 # Readline versions < 2.1 don't have rl_completion_append_character
+# Libedit lacks rl_filename_quote_characters and rl_filename_quoting_function
 
-AC_DEFUN([PGAC_VAR_RL_COMPLETION_APPEND_CHARACTER],
+AC_DEFUN([PGAC_READLINE_VARIABLES],
 [AC_CACHE_CHECK([for rl_completion_append_character], pgac_cv_var_rl_completion_append_character,
 [AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <stdio.h>
 #ifdef HAVE_READLINE_READLINE_H
@@ -228,7 +229,38 @@ AC_DEFUN([PGAC_VAR_RL_COMPLETION_APPEND_CHARACTER],
 if test x"$pgac_cv_var_rl_completion_append_character" = x"yes"; then
 AC_DEFINE(HAVE_RL_COMPLETION_APPEND_CHARACTER, 1,
           [Define to 1 if you have the global variable 'rl_completion_append_character'.])
-fi])# PGAC_VAR_RL_COMPLETION_APPEND_CHARACTER
+fi
+AC_CACHE_CHECK([for rl_filename_quote_characters], pgac_cv_var_rl_filename_quote_characters,
+[AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <stdio.h>
+#ifdef HAVE_READLINE_READLINE_H
+# include <readline/readline.h>
+#elif defined(HAVE_READLINE_H)
+# include <readline.h>
+#endif
+],
+[rl_filename_quote_characters = "x";])],
+[pgac_cv_var_rl_filename_quote_characters=yes],
+[pgac_cv_var_rl_filename_quote_characters=no])])
+if test x"$pgac_cv_var_rl_filename_quote_characters" = x"yes"; then
+AC_DEFINE(HAVE_RL_FILENAME_QUOTE_CHARACTERS, 1,
+          [Define to 1 if you have the global variable 'rl_filename_quote_characters'.])
+fi
+AC_CACHE_CHECK([for rl_filename_quoting_function], pgac_cv_var_rl_filename_quoting_function,
+[AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <stdio.h>
+#ifdef HAVE_READLINE_READLINE_H
+# include <readline/readline.h>
+#elif defined(HAVE_READLINE_H)
+# include <readline.h>
+#endif
+],
+[rl_filename_quoting_function = 0;])],
+[pgac_cv_var_rl_filename_quoting_function=yes],
+[pgac_cv_var_rl_filename_quoting_function=no])])
+if test x"$pgac_cv_var_rl_filename_quoting_function" = x"yes"; then
+AC_DEFINE(HAVE_RL_FILENAME_QUOTING_FUNCTION, 1,
+          [Define to 1 if you have the global variable 'rl_filename_quoting_function'.])
+fi
+])# PGAC_READLINE_VARIABLES
 
 
 
diff --git a/configure b/configure
index 6b1c779..97556b8 100755
--- a/configure
+++ b/configure
@@ -16409,6 +16409,81 @@ if test x"$pgac_cv_var_rl_completion_append_character" = x"yes"; then
 $as_echo "#define HAVE_RL_COMPLETION_APPEND_CHARACTER 1" >>confdefs.h
 
 fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for rl_filename_quote_characters" >&5
+$as_echo_n "checking for rl_filename_quote_characters... " >&6; }
+if ${pgac_cv_var_rl_filename_quote_characters+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+#include <stdio.h>
+#ifdef HAVE_READLINE_READLINE_H
+# include <readline/readline.h>
+#elif defined(HAVE_READLINE_H)
+# include <readline.h>
+#endif
+
+int
+main ()
+{
+rl_filename_quote_characters = "x";
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  pgac_cv_var_rl_filename_quote_characters=yes
+else
+  pgac_cv_var_rl_filename_quote_characters=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $pgac_cv_var_rl_filename_quote_characters" >&5
+$as_echo "$pgac_cv_var_rl_filename_quote_characters" >&6; }
+if test x"$pgac_cv_var_rl_filename_quote_characters" = x"yes"; then
+
+$as_echo "#define HAVE_RL_FILENAME_QUOTE_CHARACTERS 1" >>confdefs.h
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for rl_filename_quoting_function" >&5
+$as_echo_n "checking for rl_filename_quoting_function... " >&6; }
+if ${pgac_cv_var_rl_filename_quoting_function+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+#include <stdio.h>
+#ifdef HAVE_READLINE_READLINE_H
+# include <readline/readline.h>
+#elif defined(HAVE_READLINE_H)
+# include <readline.h>
+#endif
+
+int
+main ()
+{
+rl_filename_quoting_function = 0;
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  pgac_cv_var_rl_filename_quoting_function=yes
+else
+  pgac_cv_var_rl_filename_quoting_function=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $pgac_cv_var_rl_filename_quoting_function" >&5
+$as_echo "$pgac_cv_var_rl_filename_quoting_function" >&6; }
+if test x"$pgac_cv_var_rl_filename_quoting_function" = x"yes"; then
+
+$as_echo "#define HAVE_RL_FILENAME_QUOTING_FUNCTION 1" >>confdefs.h
+
+fi
+
   for ac_func in rl_completion_matches rl_filename_completion_function rl_reset_screen_size
 do :
   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
diff --git a/configure.in b/configure.in
index 2b9025c..07c00d9 100644
--- a/configure.in
+++ b/configure.in
@@ -1867,7 +1867,7 @@ fi
 LIBS="$LIBS_including_readline"
 
 if test "$with_readline" = yes; then
-  PGAC_VAR_RL_COMPLETION_APPEND_CHARACTER
+  PGAC_READLINE_VARIABLES
   AC_CHECK_FUNCS([rl_completion_matches rl_filename_completion_function rl_reset_screen_size])
   AC_CHECK_FUNCS([append_history history_truncate_file])
 fi
diff --git a/src/bin/psql/stringutils.c b/src/bin/psql/stringutils.c
index 8c8b4c2..23a6f9f 100644
--- a/src/bin/psql/stringutils.c
+++ b/src/bin/psql/stringutils.c
@@ -282,6 +282,7 @@ strip_quotes(char *source, char quote, char escape, int encoding)
  * entails_quote -	any of these present?  need outer quotes
  * quote -			doubled within string, affixed to both ends
  * escape -			doubled within string
+ * force_quote -	if true, quote the output even if it doesn't "need" it
  * encoding -		the active character-set encoding
  *
  * Do not use this as a substitute for PQescapeStringConn().  Use it for
@@ -289,12 +290,13 @@ strip_quotes(char *source, char quote, char escape, int encoding)
  */
 char *
 quote_if_needed(const char *source, const char *entails_quote,
-				char quote, char escape, int encoding)
+				char quote, char escape, bool force_quote,
+				int encoding)
 {
 	const char *src;
 	char	   *ret;
 	char	   *dst;
-	bool		need_quotes = false;
+	bool		need_quotes = force_quote;
 
 	Assert(source != NULL);
 	Assert(quote != '\0');
diff --git a/src/bin/psql/stringutils.h b/src/bin/psql/stringutils.h
index 16a7af0..fa00141 100644
--- a/src/bin/psql/stringutils.h
+++ b/src/bin/psql/stringutils.h
@@ -22,6 +22,7 @@ extern char *strtokx(const char *s,
 extern void strip_quotes(char *source, char quote, char escape, int encoding);
 
 extern char *quote_if_needed(const char *source, const char *entails_quote,
-							 char quote, char escape, int encoding);
+							 char quote, char escape, bool force_quote,
+							 int encoding);
 
 #endif							/* STRINGUTILS_H */
diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
index 2b1e3cd..a1d64f0 100644
--- a/src/bin/psql/tab-complete.c
+++ b/src/bin/psql/tab-complete.c
@@ -53,7 +53,7 @@
 #ifdef HAVE_RL_FILENAME_COMPLETION_FUNCTION
 #define filename_completion_function rl_filename_completion_function
 #else
-/* missing in some header files */
+/* decl missing in some header files, but function exists anyway */
 extern char *filename_completion_function();
 #endif
 
@@ -61,6 +61,15 @@ extern char *filename_completion_function();
 #define completion_matches rl_completion_matches
 #endif
 
+/*
+ * Currently we assume that rl_filename_dequoting_function exists if
+ * rl_filename_quoting_function does.  If that proves not to be the case,
+ * we'd need to test for the former, or possibly both, in configure.
+ */
+#ifdef HAVE_RL_FILENAME_QUOTING_FUNCTION
+#define USE_FILENAME_QUOTING_FUNCTIONS 1
+#endif
+
 /* word break characters */
 #define WORD_BREAKS		"\t\n@$><=;|&{() "
 
@@ -1112,9 +1121,9 @@ static char **get_previous_words(int point, char **buffer, int *nwords);
 
 static char *get_guctype(const char *varname);
 
-#ifdef NOT_USED
+#ifdef USE_FILENAME_QUOTING_FUNCTIONS
 static char *quote_file_name(char *text, int match_type, char *quote_pointer);
-static char *dequote_file_name(char *text, char quote_char);
+static char *dequote_file_name(char *text, int quote_char);
 #endif
 
 
@@ -1127,8 +1136,32 @@ initialize_readline(void)
 	rl_readline_name = (char *) pset.progname;
 	rl_attempted_completion_function = psql_completion;
 
+#ifdef USE_FILENAME_QUOTING_FUNCTIONS
+	rl_filename_quoting_function = quote_file_name;
+	rl_filename_dequoting_function = dequote_file_name;
+#endif
+
 	rl_basic_word_break_characters = WORD_BREAKS;
 
+	rl_completer_quote_characters = "'\"";
+
+	/*
+	 * Set rl_filename_quote_characters to "all possible characters",
+	 * otherwise Readline will skip filename quoting if it thinks a filename
+	 * doesn't need quoting.  Readline actually interprets this as bytes, so
+	 * there are no encoding considerations here.
+	 */
+#ifdef HAVE_RL_FILENAME_QUOTE_CHARACTERS
+	{
+		unsigned char *fqc = (unsigned char *) pg_malloc(256);
+
+		for (int i = 0; i < 255; i++)
+			fqc[i] = (unsigned char) (i + 1);
+		fqc[255] = '\0';
+		rl_filename_quote_characters = (const char *) fqc;
+	}
+#endif
+
 	completion_max_records = 1000;
 
 	/*
@@ -4343,12 +4380,31 @@ complete_from_variables(const char *text, const char *prefix, const char *suffix
 
 /*
  * This function wraps rl_filename_completion_function() to strip quotes from
- * the input before searching for matches and to quote any matches for which
- * the consuming command will require it.
+ * the input before searching for matches and then re-quote the matches.
+ * (We always quote filenames, even though for some psql meta-commands and
+ * some filenames it wouldn't be strictly necessary.)
+ *
+ * Caller must set completion_charp to a zero- or one-character string
+ * containing the escape character.  This is necessary since \copy has no
+ * escape character, but every other backslash command recognizes "\" as an
+ * escape character.  Since we have only two callers, don't bother providing
+ * a macro to simplify this.
  */
 static char *
 complete_from_files(const char *text, int state)
 {
+#ifdef USE_FILENAME_QUOTING_FUNCTIONS
+	/*
+	 * If we're using a version of Readline that exports filename quoting
+	 * hooks, use those, and invoke rl_filename_completion_function without
+	 * any funny business.  Readline does stuff internally that does not work
+	 * well at all if we try to handle dequoting here.
+	 */
+	return filename_completion_function(text, state);
+#else
+	/*
+	 * Otherwise, we have to do the best we can.
+	 */
 	static const char *unquoted_text;
 	char	   *unquoted_match;
 	char	   *ret = NULL;
@@ -4369,15 +4425,11 @@ complete_from_files(const char *text, int state)
 	unquoted_match = filename_completion_function(unquoted_text, state);
 	if (unquoted_match)
 	{
-		/*
-		 * Caller sets completion_charp to a zero- or one-character string
-		 * containing the escape character.  This is necessary since \copy has
-		 * no escape character, but every other backslash command recognizes
-		 * "\" as an escape character.  Since we have only two callers, don't
-		 * bother providing a macro to simplify this.
-		 */
+		/* Re-quote the result. */
 		ret = quote_if_needed(unquoted_match, " \t\r\n\"`",
-							  '\'', *completion_charp, pset.encoding);
+							  '\'', *completion_charp,
+							  true,
+							  pset.encoding);
 		if (ret)
 			free(unquoted_match);
 		else
@@ -4385,6 +4437,7 @@ complete_from_files(const char *text, int state)
 	}
 
 	return ret;
+#endif							/* USE_FILENAME_QUOTING_FUNCTIONS */
 }
 
 
@@ -4636,46 +4689,60 @@ get_guctype(const char *varname)
 	return guctype;
 }
 
-#ifdef NOT_USED
+#ifdef USE_FILENAME_QUOTING_FUNCTIONS
 
 /*
- * Surround a string with single quotes. This works for both SQL and
- * psql internal. Currently disabled because it is reported not to
- * cooperate with certain versions of readline.
+ * Quote a filename according to SQL rules, returning a malloc'd string.
+ * completion_charp must point to escape character or '\0', as per
+ * comments for complete_from_files().
  */
 static char *
 quote_file_name(char *text, int match_type, char *quote_pointer)
 {
 	char	   *s;
-	size_t		length;
 
-	(void) quote_pointer;		/* not used */
+	/* We always quote (so quote_if_needed's API is overkill) */
+	s = quote_if_needed(text, " \t\r\n\"`",
+						'\'', *completion_charp,
+						true,
+						pset.encoding);
+
+	/*
+	 * If quote_pointer is passed, it's better to handle the trailing quote
+	 * that way.
+	 */
+	if (quote_pointer && s && *s)
+	{
+		char	   *send = s + strlen(s) - 1;
 
-	length = strlen(text) +(match_type == SINGLE_MATCH ? 3 : 2);
-	s = pg_malloc(length);
-	s[0] = '\'';
-	strcpy(s + 1, text);
-	if (match_type == SINGLE_MATCH)
-		s[length - 2] = '\'';
-	s[length - 1] = '\0';
+		Assert(*send == '\'');
+		*send = '\0';
+		*quote_pointer = '\'';
+	}
 	return s;
 }
 
+/*
+ * Dequote a filename, if it's quoted.
+ * completion_charp must point to escape character or '\0', as per
+ * comments for complete_from_files().
+ */
 static char *
-dequote_file_name(char *text, char quote_char)
+dequote_file_name(char *text, int quote_char)
 {
-	char	   *s;
-	size_t		length;
-
-	if (!quote_char)
-		return pg_strdup(text);
+	char	   *unquoted_text = strtokx(text, "", NULL, "'", *completion_charp,
+										false, true, pset.encoding);
 
-	length = strlen(text);
-	s = pg_malloc(length - 2 + 1);
-	strlcpy(s, text +1, length - 2 + 1);
-
-	return s;
+	/* expect a NULL return for the empty string only */
+	if (!unquoted_text)
+	{
+		Assert(*text == '\0');
+		unquoted_text = text;
+	}
+	/* readline expects a malloc'd result that it is to free */
+	return pg_strdup(unquoted_text);
 }
-#endif							/* NOT_USED */
+
+#endif							/* USE_FILENAME_QUOTING_FUNCTIONS */
 
 #endif							/* USE_READLINE */
diff --git a/src/include/pg_config.h.in b/src/include/pg_config.h.in
index 939245d..e3baae8 100644
--- a/src/include/pg_config.h.in
+++ b/src/include/pg_config.h.in
@@ -492,6 +492,14 @@
 /* Define to 1 if you have the `rl_filename_completion_function' function. */
 #undef HAVE_RL_FILENAME_COMPLETION_FUNCTION
 
+/* Define to 1 if you have the global variable 'rl_filename_quote_characters'.
+   */
+#undef HAVE_RL_FILENAME_QUOTE_CHARACTERS
+
+/* Define to 1 if you have the global variable 'rl_filename_quoting_function'.
+   */
+#undef HAVE_RL_FILENAME_QUOTING_FUNCTION
+
 /* Define to 1 if you have the `rl_reset_screen_size' function. */
 #undef HAVE_RL_RESET_SCREEN_SIZE
 
diff --git a/src/include/pg_config.h.win32 b/src/include/pg_config.h.win32
index 36e6bdc..1ca90b1 100644
--- a/src/include/pg_config.h.win32
+++ b/src/include/pg_config.h.win32
@@ -355,6 +355,14 @@
 /* Define to 1 if you have the `rl_filename_completion_function' function. */
 /* #undef HAVE_RL_FILENAME_COMPLETION_FUNCTION */
 
+/* Define to 1 if you have the global variable 'rl_filename_quote_characters'.
+   */
+/* #undef HAVE_RL_FILENAME_QUOTE_CHARACTERS */
+
+/* Define to 1 if you have the global variable 'rl_filename_quoting_function'.
+   */
+/* #undef HAVE_RL_FILENAME_QUOTING_FUNCTION */
+
 /* Define to 1 if you have the <security/pam_appl.h> header file. */
 /* #undef HAVE_SECURITY_PAM_APPL_H */