lib-mail: Change rfc822_parser_context.nul_replacement_char to string

src/lib-mail/message-address.c

@@ -426,7 +426,7 @@ message_address_parse_real(pool_t pool, const unsigned char *data, size_t size,
 	i_zero(&ctx);
 
 	rfc822_parser_init(&ctx.parser, data, size, t_str_new(128));
-	ctx.parser.nul_replacement_char = RFC822_NUL_REPLACEMENT_CHAR;
+	ctx.parser.nul_replacement_str = RFC822_NUL_REPLACEMENT_STR;
 	ctx.pool = pool;
 	ctx.str = t_str_new(128);
 	ctx.fill_missing = fill_missing;

src/lib-mail/rfc2231-parser.c

@@ -47,13 +47,13 @@ int rfc2231_parse(struct rfc822_parser_context *ctx,
 	string_t *str;
 	unsigned int i, j, count, next, next_idx;
 	bool ok, have_extended, broken = FALSE;
-	char prev_replacement_char;
+	const char *prev_replacement_str;
 	int ret;
 
 	/* Temporarily replace the nul_replacement_char while we're parsing
 	   the content-params. It'll be restored before we return. */
-	prev_replacement_char = ctx->nul_replacement_char;
-	ctx->nul_replacement_char = RFC822_NUL_REPLACEMENT_CHAR;
+	prev_replacement_str = ctx->nul_replacement_str;
+	ctx->nul_replacement_str = RFC822_NUL_REPLACEMENT_STR;
 
 	/* Get a list of all parameters. RFC 2231 uses key*<n>[*]=value pairs,
 	   which we want to merge to a key[*]=value pair. Save them to a
@@ -103,7 +103,7 @@ int rfc2231_parse(struct rfc822_parser_context *ctx,
 			array_append(&result, &value, 1);
 		}
 	}
-	ctx->nul_replacement_char = prev_replacement_char;
+	ctx->nul_replacement_str = prev_replacement_str;
 
 	if (array_count(&rfc2231_params_arr) == 0) {
 		/* No RFC 2231 parameters */

src/lib-mail/rfc822-parser.c

@@ -77,11 +77,11 @@ int rfc822_skip_comment(struct rfc822_parser_context *ctx)
 		switch (*ctx->data) {
 		case '\0':
 			if (ctx->last_comment != NULL &&
-			    ctx->nul_replacement_char != '\0') {
+			    ctx->nul_replacement_str != NULL) {
 				str_append_data(ctx->last_comment, start,
 						ctx->data - start);
-				str_append_c(ctx->last_comment,
-					     ctx->nul_replacement_char);
+				str_append(ctx->last_comment,
+					   ctx->nul_replacement_str);
 				start = ctx->data + 1;
 			}
 			break;
@@ -247,9 +247,9 @@ int rfc822_parse_quoted_string(struct rfc822_parser_context *ctx, string_t *str)
 	for (start = ctx->data; ctx->data < ctx->end; ctx->data++) {
 		switch (*ctx->data) {
 		case '\0':
-			if (ctx->nul_replacement_char != '\0') {
+			if (ctx->nul_replacement_str != NULL) {
 				str_append_data(str, start, ctx->data - start);
-				str_append_c(str, ctx->nul_replacement_char);
+				str_append(str, ctx->nul_replacement_str);
 				start = ctx->data + 1;
 			}
 			break;
@@ -364,9 +364,9 @@ rfc822_parse_domain_literal(struct rfc822_parser_context *ctx, string_t *str)
 	for (start = ctx->data++; ctx->data < ctx->end; ctx->data++) {
 		switch (*ctx->data) {
 		case '\0':
-			if (ctx->nul_replacement_char != '\0') {
+			if (ctx->nul_replacement_str != NULL) {
 				str_append_data(str, start, ctx->data - start);
-				str_append_c(str, ctx->nul_replacement_char);
+				str_append(str, ctx->nul_replacement_str);
 				start = ctx->data + 1;
 			}
 			break;

src/lib-mail/rfc822-parser.h

@@ -2,14 +2,14 @@
 #define RFC822_PARSER_H
 
 /* This can be used as a common NUL replacement character */
-#define RFC822_NUL_REPLACEMENT_CHAR 0x80
+#define RFC822_NUL_REPLACEMENT_STR "\x80"
 
 struct rfc822_parser_context {
 	const unsigned char *data, *end;
 	string_t *last_comment;
 
-	/* Replace NULs with this character */
-	char nul_replacement_char;
+	/* Replace NUL characters with this string */
+	const char *nul_replacement_str;
 };
 
 #define IS_ATEXT(c) \

src/lib-mail/test-rfc822-parser.c

@@ -68,7 +68,7 @@ static void test_rfc822_parse_comment_nuls(void)
 
 	str_truncate(str, 0);
 	rfc822_parser_init(&parser, input, sizeof(input)-1, str);
-	parser.nul_replacement_char = '!';
+	parser.nul_replacement_str = "!";
 	test_assert(rfc822_skip_comment(&parser) == 0);
 	test_assert(strcmp(str_c(str), output) == 0);
 	rfc822_parser_deinit(&parser);