config: Fix the "include" command.

Previously, it only pretended to rewrite the configuration file, so it
set or cleared OPT_MUST_SAVE but never changed or output any options.
Now, it actually sets the options when ELinks is loading the
configuration file.  Also, when ELinks is rewriting the configuration
file, it now compares the values in the included file to the current
values of the options, and sets or clears OPT_MUST_SAVE accordingly.

src/config/conf.c

@@ -193,7 +193,7 @@ skip_to_unquoted_newline_or_comment(struct conf_parsing_pos *pos)
 /* If dynamic string credentials are supplied, we will mirror the command at
  * the end of the string; however, we won't load the option value to the tree,
  * and we will even write option value from the tree to the output string.
- * We will only possibly clear OPT_MUST_SAVE flag in the option.  */
+ * We will only possibly set or clear OPT_MUST_SAVE flag in the option.  */
 
 static enum parse_error
 parse_set(struct option *opt_tree, struct conf_parsing_state *state,
@@ -290,6 +290,16 @@ parse_set(struct option *opt_tree, struct conf_parsing_state *state,
 				mem_free(val);
 				return show_parse_error(state, ERROR_VALUE);
 			}
+		} else if (is_system_conf) {
+			/* scanning a file that will not be rewritten */
+			struct option *flagsite = indirect_option(opt);
+
+			if (!(flagsite->flags & OPT_DELETED)
+			    && option_types[opt->type].equals
+			    && option_types[opt->type].equals(opt, val))
+				flagsite->flags &= ~OPT_MUST_SAVE;
+			else
+				flagsite->flags |= OPT_MUST_SAVE;
 		} else {
 			/* rewriting a configuration file */
 			struct option *flagsite = indirect_option(opt);
@@ -360,6 +370,14 @@ parse_unset(struct option *opt_tree, struct conf_parsing_state *state,
 			/* loading a configuration file */
 			if (opt->flags & OPT_ALLOC) delete_option(opt);
 			else mark_option_as_deleted(opt);
+		} else if (is_system_conf) {
+			/* scanning a file that will not be rewritten */
+			struct option *flagsite = indirect_option(opt);
+
+			if (flagsite->flags & OPT_DELETED)
+				flagsite->flags &= ~OPT_MUST_SAVE;
+			else
+				flagsite->flags |= OPT_MUST_SAVE;
 		} else {
 			/* rewriting a configuration file */
 			struct option *flagsite = indirect_option(opt);
@@ -453,6 +471,9 @@ parse_bind(struct option *opt_tree, struct conf_parsing_state *state,
 		} else {
 			err = ERROR_NONE;
 		}
+	} else if (is_system_conf) {
+		/* scanning a file that will not be rewritten */
+		/* TODO */
 	} else {
 		/* rewriting a configuration file */
 		/* Mirror what we already have.  If the keystroke has
@@ -513,7 +534,8 @@ parse_include(struct option *opt_tree, struct conf_parsing_state *state,
 	 * CONFDIR/<otherfile> ;). --pasky */
 	if (load_config_file(fname[0] == '/' ? (unsigned char *) ""
 					     : elinks_home,
-			     fname, opt_tree, &dumbstring, is_system_conf)) {
+			     fname, opt_tree, 
+			     mirror ? &dumbstring : NULL, 1)) {
 		done_string(&dumbstring);
 		mem_free(fname);
 		return show_parse_error(state, ERROR_VALUE);

src/config/options.h

@@ -30,12 +30,19 @@ enum option_flags {
 	 * has value 3, saving works like this:
 	 * - First, ELinks sets OPT_MUST_SAVE in the options that have
 	 *   OPT_TOUCHED or OPT_DELETED, and clears it in the rest.
-	 * - ELinks then parses the old configuration file.  If it
+	 * - ELinks then parses the old configuration file and any
-	 *   contains a "set" or "unset" command for this option,
+	 *   files named in "include" commands.
-	 *   ELinks rewrites the command and clears OPT_MUST_SAVE.
+	 * - If the old configuration file contains a "set" or "unset"
-	 * - After ELinks has rewritten the configuration file, it
+	 *   command for this option, ELinks rewrites the command and
-	 *   appends the options that still have the OPT_MUST_SAVE
+	 *   clears OPT_MUST_SAVE.
-	 *   flag.
+	 * - If an included file contains a "set" or "unset" command
+	 *   for this option, ELinks compares the value of the option
+	 *   to the value given in the command.  ELinks clears
+	 *   OPT_MUST_SAVE if the values match, or sets it if they
+	 *   differ.
+	 * - After ELinks has rewritten the configuration file and
+	 *   parsed the included files, it appends the options that
+	 *   still have the OPT_MUST_SAVE flag.
 	 * Other saving styles are variants of this:
 	 * - 0: ELinks does not append any options to the
 	 *   configuration file.  So OPT_MUST_SAVE has no effect.

src/config/opttypes.c

@@ -162,6 +162,28 @@ redir_set(struct option *opt, unsigned char *str)
 	return ret;
 }
 
+static int
+redir_eq(struct option *opt, const unsigned char *str)
+{
+	struct option *real = get_opt_rec(config_options, opt->value.string);
+	int ret = 0;
+
+	assertm(real != NULL, "%s aliased to unknown option %s!", opt->name, opt->value.string);
+	if_assert_failed { return ret; }
+
+	if (option_types[real->type].equals) {
+		long negated;
+
+		if ((opt->flags & OPT_ALIAS_NEGATE) && real->type == OPT_BOOL) {
+			negated = !*(const long *) str;
+			str = (unsigned char *) &negated;
+		}
+		ret = option_types[real->type].equals(real, str);
+	}
+
+	return ret;
+}
+
 
 
 /* Support functions for config file parsing. */
@@ -207,6 +229,12 @@ num_set(struct option *opt, unsigned char *str)
 	return 1;
 }
 
+static int
+num_eq(struct option *opt, const unsigned char *str)
+{
+	return str && opt->value.number == *(const long *) str;
+}
+
 static void
 num_wr(struct option *option, struct string *string)
 {
@@ -221,6 +249,12 @@ long_set(struct option *opt, unsigned char *str)
 	return 1;
 }
 
+static int
+long_eq(struct option *opt, const unsigned char *str)
+{
+	return str && opt->value.big_number == *(const long *) str;
+}
+
 static void
 long_wr(struct option *option, struct string *string)
 {
@@ -290,6 +324,12 @@ str_set(struct option *opt, unsigned char *str)
 	return 1;
 }
 
+static int
+str_eq(struct option *opt, const unsigned char *str)
+{
+	return str && strcmp(opt->value.string, str) == 0;
+}
+
 static void
 str_wr(struct option *o, struct string *s)
 {
@@ -320,6 +360,12 @@ cp_set(struct option *opt, unsigned char *str)
 	return 1;
 }
 
+static int
+cp_eq(struct option *opt, const unsigned char *str)
+{
+	return str && get_cp_index(str) == opt->value.number;
+}
+
 static void
 cp_wr(struct option *o, struct string *s)
 {
@@ -339,6 +385,16 @@ lang_set(struct option *opt, unsigned char *str)
 	return 1;
 }
 
+static int
+lang_eq(struct option *opt, const unsigned char *str)
+{
+#ifdef CONFIG_NLS
+	return str && name_to_language(str) == opt->value.number;
+#else
+	return 1;		/* All languages are the same.  */
+#endif
+}
+
 static void
 lang_wr(struct option *o, struct string *s)
 {
@@ -360,6 +416,15 @@ color_set(struct option *opt, unsigned char *str)
 	return !decode_color(str, strlen(str), &opt->value.color);
 }
 
+static int
+color_eq(struct option *opt, const unsigned char *str)
+{
+	color_T color;
+
+	return str && !decode_color(str, strlen(str), &color)
+		&& color == opt->value.color;
+}
+
 static void
 color_wr(struct option *opt, struct string *str)
 {
@@ -404,29 +469,29 @@ const struct option_type_info option_types[] = {
 	/* The OPT_ comments below are here to be found by grep.  */
 
 	/* OPT_BOOL */
-	{ N_("Boolean"),  bool_cmd,  num_rd,   num_wr,   NULL,     num_set,   N_("[0|1]") },
+	{ N_("Boolean"),  bool_cmd,  num_rd,   num_wr,   NULL,     num_set,   num_eq,   N_("[0|1]") },
 	/* OPT_INT */
-	{ N_("Integer"),  gen_cmd,   num_rd,   num_wr,   NULL,     num_set,   N_("<num>") },
+	{ N_("Integer"),  gen_cmd,   num_rd,   num_wr,   NULL,     num_set,   num_eq,   N_("<num>") },
 	/* OPT_LONG */
-	{ N_("Longint"),  gen_cmd,   num_rd,   long_wr,  NULL,     long_set,  N_("<num>") },
+	{ N_("Longint"),  gen_cmd,   num_rd,   long_wr,  NULL,     long_set,  long_eq,  N_("<num>") },
 	/* OPT_STRING */
-	{ N_("String"),   gen_cmd,   str_rd,   str_wr,   str_dup,  str_set,   N_("<str>") },
+	{ N_("String"),   gen_cmd,   str_rd,   str_wr,   str_dup,  str_set,   str_eq,   N_("<str>") },
 
 	/* OPT_CODEPAGE */
-	{ N_("Codepage"), gen_cmd,   str_rd,   cp_wr,    NULL,     cp_set,    N_("<codepage>") },
+	{ N_("Codepage"), gen_cmd,   str_rd,   cp_wr,    NULL,     cp_set,    cp_eq,    N_("<codepage>") },
 	/* OPT_LANGUAGE */
-	{ N_("Language"), gen_cmd,   str_rd,   lang_wr,  NULL,     lang_set,  N_("<language>") },
+	{ N_("Language"), gen_cmd,   str_rd,   lang_wr,  NULL,     lang_set,  lang_eq,  N_("<language>") },
 	/* OPT_COLOR */
-	{ N_("Color"),    gen_cmd,   str_rd,   color_wr, NULL,     color_set, N_("<color|#rrggbb>") },
+	{ N_("Color"),    gen_cmd,   str_rd,   color_wr, NULL,     color_set, color_eq, N_("<color|#rrggbb>") },
 
 	/* OPT_COMMAND */
-	{ N_("Special"),  exec_cmd,  NULL,     NULL,     NULL,     NULL,      "" },
+	{ N_("Special"),  exec_cmd,  NULL,     NULL,     NULL,     NULL,      NULL,     "" },
 
 	/* OPT_ALIAS */
-	{ N_("Alias"),    redir_cmd, redir_rd, redir_wr, NULL,     redir_set, "" },
+	{ N_("Alias"),    redir_cmd, redir_rd, redir_wr, NULL,     redir_set, redir_eq, "" },
 
 	/* OPT_TREE */
-	{ N_("Folder"),   NULL,      NULL,     NULL,     tree_dup, NULL,      "" },
+	{ N_("Folder"),   NULL,      NULL,     NULL,     tree_dup, NULL,      NULL,      "" },
 };
 
 unsigned char *

src/config/opttypes.h

@@ -11,6 +11,7 @@ struct option_type_info {
 	void (*write)(struct option *, struct string *);
 	void (*dup)(struct option *, struct option *);
 	int (*set)(struct option *, unsigned char *);
+	int (*equals)(struct option *, const unsigned char *);
 	unsigned char *help_str;
 };