From: Timo Sirainen <tss@iki.fi>
Date: Tue, 20 Apr 2010 11:57:19 +0000 (+0300)
Subject: Added support for mail search input parsers. doveadm now uses command line parser.
X-Git-Tag: 2.0.beta5~99
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=5c2d695acf9f95ae0dcdda89c4d2391ceda4d672;p=thirdparty%2Fdovecot%2Fcore.git

Added support for mail search input parsers. doveadm now uses command line parser.

--HG--
branch : HEAD
---

diff --git a/src/doveadm/Makefile.am b/src/doveadm/Makefile.am
index 546e73f595..50719ce7f9 100644
--- a/src/doveadm/Makefile.am
+++ b/src/doveadm/Makefile.am
@@ -20,7 +20,8 @@ AM_CPPFLAGS = \
 if !BUILD_SHARED_LIBS
 unused_objects = \
 	../lib/mountpoint.o \
-	../lib-imap/imap-util.o
+	../lib-imap/imap-util.o \
+	../lib-storage/mail-search-parser-imap.o
 endif
 
 cmd_pw_libs = \
diff --git a/src/doveadm/doveadm-mail-fetch.c b/src/doveadm/doveadm-mail-fetch.c
index ad099c3aad..b431a7a49a 100644
--- a/src/doveadm/doveadm-mail-fetch.c
+++ b/src/doveadm/doveadm-mail-fetch.c
@@ -6,60 +6,25 @@
 #include "base64.h"
 #include "randgen.h"
 #include "str.h"
-#include "imap-quote.h"
-#include "imap-parser.h"
 #include "mail-storage.h"
 #include "mail-search-build.h"
+#include "mail-search-parser.h"
 #include "doveadm-mail.h"
 
-static struct mail_search_args *search_args_from_str(const char *str)
+static struct mail_search_args *build_search_args(const char *const args[])
 {
-	struct istream *input;
-	struct imap_parser *parser;
-	const struct imap_arg *args;
+	struct mail_search_parser *parser;
 	struct mail_search_args *sargs;
 	const char *error;
-	bool fatal;
-	int ret;
-
-	input = i_stream_create_from_data(str, strlen(str));
-	(void)i_stream_read(input);
 
-	parser = imap_parser_create(input, NULL, (size_t)-1);
-	ret = imap_parser_finish_line(parser, 0,  0, &args);
-	if (ret < 0)
-		i_fatal("%s", imap_parser_get_error(parser, &fatal));
-	if (mail_search_build_from_imap_args(mail_search_register_human,
-					     args, "UTF-8", &sargs, &error) < 0)
+	parser = mail_search_parser_init_cmdline(args);
+	if (mail_search_build(mail_search_register_human, parser, "UTF-8",
+			      &sargs, &error) < 0)
 		i_fatal("%s", error);
-
-	imap_parser_destroy(&parser);
-	i_stream_destroy(&input);
+	mail_search_parser_deinit(&parser);
 	return sargs;
 }
 
-static const char *params_to_imap_args_string(const char *const args[])
-{
-	string_t *str;
-	const char *p;
-
-	str = t_str_new(256);
-	for (; *args != NULL; args++) {
-		for (p = *args; *p != '\0'; p++) {
-			if (IS_ATOM_SPECIAL_INPUT(*p))
-				break;
-		}
-		if (*p == '\0' ||
-		    strcmp(*args, "(") == 0 ||
-		    strcmp(*args, ")") == 0)
-			str_append(str, *args);
-		else
-			imap_dquote_append(str, *args);
-		str_append_c(str, ' ');
-	}
-	return str_c(str);
-}
-
 void cmd_fetch(struct mail_user *user, const char *const args[])
 {
 	const char *mailbox = args[0];
@@ -77,7 +42,7 @@ void cmd_fetch(struct mail_user *user, const char *const args[])
 
 	if (mailbox == NULL || args[1] == NULL)
 		doveadm_mail_help_name("fetch");
-	search_args = search_args_from_str(params_to_imap_args_string(args+1));
+	search_args = build_search_args(args+1);
 
 	random_fill_weak(prefix_buf, sizeof(prefix_buf));
 	prefix = t_str_new(32);
diff --git a/src/imap/imap-search-args.c b/src/imap/imap-search-args.c
index 1980bc1060..fcbc3ce9ca 100644
--- a/src/imap/imap-search-args.c
+++ b/src/imap/imap-search-args.c
@@ -2,6 +2,7 @@
 
 #include "imap-common.h"
 #include "mail-storage.h"
+#include "mail-search-parser.h"
 #include "mail-search-build.h"
 #include "imap-search-args.h"
 #include "imap-parser.h"
@@ -39,17 +40,21 @@ int imap_search_args_build(struct client_command_context *cmd,
 			   const struct imap_arg *args, const char *charset,
 			   struct mail_search_args **search_args_r)
 {
+	struct mail_search_parser *parser;
 	struct mail_search_args *sargs;
 	const char *error;
+	int ret;
 
 	if (IMAP_ARG_IS_EOL(args)) {
 		client_send_command_error(cmd, "Missing search parameters");
 		return -1;
 	}
 
-	if (mail_search_build_from_imap_args(mail_search_register_imap,
-					     args, charset,
-					     &sargs, &error) < 0) {
+	parser = mail_search_parser_init_imap(args);
+	ret = mail_search_build(mail_search_register_imap, parser, charset,
+				&sargs, &error);
+	mail_search_parser_deinit(&parser);
+	if (ret < 0) {
 		client_send_command_error(cmd, error);
 		return -1;
 	}
diff --git a/src/lib-storage/Makefile.am b/src/lib-storage/Makefile.am
index 472fbf83eb..01813737af 100644
--- a/src/lib-storage/Makefile.am
+++ b/src/lib-storage/Makefile.am
@@ -22,6 +22,9 @@ libstorage_la_SOURCES = \
 	mail-namespace.c \
 	mail-search.c \
 	mail-search-build.c \
+	mail-search-parser.c \
+	mail-search-parser-imap.c \
+	mail-search-parser-cmdline.c \
 	mail-search-register.c \
 	mail-search-register-human.c \
 	mail-search-register-imap.c \
@@ -47,6 +50,8 @@ headers = \
 	mail-search-register.h \
 	mail-thread.h \
 	mail-storage.h \
+	mail-search-parser.h \
+	mail-search-parser-private.h \
 	mail-storage-private.h \
 	mail-storage-hooks.h \
 	mail-storage-service.h \
diff --git a/src/lib-storage/mail-search-build.c b/src/lib-storage/mail-search-build.c
index 35bcb90ff9..8b1f998a7c 100644
--- a/src/lib-storage/mail-search-build.c
+++ b/src/lib-storage/mail-search-build.c
@@ -1,29 +1,15 @@
 /* Copyright (c) 2002-2010 Dovecot authors, see the included COPYING file */
 
 #include "lib.h"
-#include "imap-arg.h"
 #include "mail-storage-private.h"
 #include "mail-search-register.h"
+#include "mail-search-parser.h"
 #include "mail-search-build.h"
 
 #include <stdlib.h>
 
-int mail_search_build_next_astring(struct mail_search_build_context *ctx,
-				   const struct imap_arg **imap_args,
-				   const char **value_r)
-{
-	if (IMAP_ARG_IS_EOL(*imap_args)) {
-		ctx->error = "Missing parameter for argument";
-		return -1;
-	}
-	if (!imap_arg_get_astring(*imap_args, value_r)) {
-		ctx->error = "Invalid parameter for argument";
-		return -1;
-	}
-
-	*imap_args += 1;
-	return 0;
-}
+static int mail_search_build_list(struct mail_search_build_context *ctx,
+				  struct mail_search_arg **arg_r);
 
 struct mail_search_arg *
 mail_search_build_new(struct mail_search_build_context *ctx,
@@ -38,93 +24,88 @@ mail_search_build_new(struct mail_search_build_context *ctx,
 
 struct mail_search_arg *
 mail_search_build_str(struct mail_search_build_context *ctx,
-		      const struct imap_arg **imap_args,
 		      enum mail_search_arg_type type)
 {
 	struct mail_search_arg *sarg;
 	const char *value;
 
 	sarg = mail_search_build_new(ctx, type);
-	if (mail_search_build_next_astring(ctx, imap_args, &value) < 0)
+	if (mail_search_parse_string(ctx->parser, &value) < 0)
 		return NULL;
 	sarg->value.str = p_strdup(ctx->pool, value);
 	return sarg;
 }
 
-struct mail_search_arg *
-mail_search_build_next(struct mail_search_build_context *ctx,
-		       struct mail_search_arg *parent,
-		       const struct imap_arg **imap_args)
+static int
+mail_search_build_key_int(struct mail_search_build_context *ctx,
+			  struct mail_search_arg *parent,
+			  struct mail_search_arg **arg_r)
 {
 	struct mail_search_arg *sarg;
 	struct mail_search_arg *old_parent = ctx->parent;
-	const struct imap_arg *listargs;
 	const char *key;
 	const struct mail_search_register_arg *reg_arg;
 	mail_search_register_fallback_t *fallback;
+	int ret;
 
 	ctx->parent = parent;
 
-	if (IMAP_ARG_IS_EOL(*imap_args)) {
-		ctx->error = "Missing argument";
-		return NULL;
-	}
-
-	if ((*imap_args)->type == IMAP_ARG_NIL) {
-		/* NIL not allowed */
-		ctx->error = "NIL not allowed";
-		return NULL;
-	}
-
-	if (imap_arg_get_list(*imap_args, &listargs)) {
-		if (IMAP_ARG_IS_EOL(listargs)) {
-			ctx->error = "Empty list not allowed";
-			return NULL;
-		}
+	if ((ret = mail_search_parse_key(ctx->parser, &key)) <= 0)
+		return ret;
 
-		sarg = mail_search_build_list(ctx, listargs);
-		*imap_args += 1;
+	if (strcmp(key, MAIL_SEARCH_PARSER_KEY_LIST) == 0) {
+		if (mail_search_build_list(ctx, &sarg) < 0)
+			return -1;
+		i_assert(sarg->value.subargs != NULL);
 		ctx->parent = old_parent;
-		return sarg;
+		*arg_r = sarg;
+		return 1;
 	}
-
-	/* string argument - get the name and jump to next */
-	key = imap_arg_as_astring(*imap_args);
-	*imap_args += 1;
 	key = t_str_ucase(key);
 
 	reg_arg = mail_search_register_find(ctx->reg, key);
 	if (reg_arg != NULL)
-		sarg = reg_arg->build(ctx, imap_args);
+		sarg = reg_arg->build(ctx);
 	else if (mail_search_register_get_fallback(ctx->reg, &fallback))
-		sarg = fallback(ctx, key, imap_args);
+		sarg = fallback(ctx, key);
 	else {
 		sarg = NULL;
-		ctx->error = p_strconcat(ctx->pool, "Unknown argument ",
-					 key, NULL);
+		ctx->_error = p_strconcat(ctx->pool, "Unknown argument ",
+					  key, NULL);
 	}
 
 	ctx->parent = old_parent;
-	return sarg;
+	*arg_r = sarg;
+	return sarg == NULL ? -1 : 1;
 }
 
-struct mail_search_arg *
-mail_search_build_list(struct mail_search_build_context *ctx,
-		       const struct imap_arg *imap_args)
+int mail_search_build_key(struct mail_search_build_context *ctx,
+			  struct mail_search_arg *parent,
+			  struct mail_search_arg **arg_r)
+{
+	int ret;
+
+	ret = mail_search_build_key_int(ctx, parent, arg_r);
+	if (ret <= 0) {
+		if (ret == 0)
+			ctx->_error = "Missing argument";
+		return -1;
+	}
+	return 0;
+}
+
+static int mail_search_build_list(struct mail_search_build_context *ctx,
+				  struct mail_search_arg **arg_r)
 {
 	struct mail_search_arg *sarg, **subargs;
 	enum mail_search_arg_type cur_type = SEARCH_SUB;
+	int ret;
 
 	sarg = p_new(ctx->pool, struct mail_search_arg, 1);
 	sarg->type = cur_type;
 
 	subargs = &sarg->value.subargs;
-	while (!IMAP_ARG_IS_EOL(imap_args)) {
-		sarg->type = SEARCH_SUB;
-		*subargs = mail_search_build_next(ctx, sarg, &imap_args);
-		if (*subargs == NULL)
-			return NULL;
-
+	while ((ret = mail_search_build_key_int(ctx, sarg, subargs)) > 0) {
 		if (cur_type == sarg->type) {
 			/* expected type */
 		} else if (cur_type == SEARCH_SUB) {
@@ -132,21 +113,24 @@ mail_search_build_list(struct mail_search_build_context *ctx,
 			   belong to this type. */
 			cur_type = sarg->type;
 		} else {
-			ctx->error = cur_type == SEARCH_OR ?
+			ctx->_error = cur_type == SEARCH_OR ?
 				"Use parenthesis when using ORs" :
 				"Use parenthesis when mixing subtypes";
-			return NULL;
+			return -1;
 		}
 		subargs = &(*subargs)->next;
+		sarg->type = SEARCH_SUB;
 	}
-	return sarg;
+	if (ret < 0)
+		return -1;
+	sarg->type = cur_type;
+	*arg_r = sarg;
+	return 0;
 }
 
-int mail_search_build_from_imap_args(struct mail_search_register *reg,
-				     const struct imap_arg *imap_args,
-				     const char *charset,
-				     struct mail_search_args **args_r,
-				     const char **error_r)
+int mail_search_build(struct mail_search_register *reg,
+		      struct mail_search_parser *parser, const char *charset,
+		      struct mail_search_args **args_r, const char **error_r)
 {
         struct mail_search_build_context ctx;
 	struct mail_search_args *args;
@@ -161,10 +145,11 @@ int mail_search_build_from_imap_args(struct mail_search_register *reg,
 	memset(&ctx, 0, sizeof(ctx));
 	ctx.pool = args->pool;
 	ctx.reg = reg;
+	ctx.parser = parser;
 
-	root = mail_search_build_list(&ctx, imap_args);
-	if (root == NULL) {
-		*error_r = t_strdup(ctx.error);
+	if (mail_search_build_list(&ctx, &root) < 0) {
+		*error_r = ctx._error != NULL ? t_strdup(ctx._error) :
+			t_strdup(mail_search_parser_get_error(parser));
 		pool_unref(&args->pool);
 		return -1;
 	}
diff --git a/src/lib-storage/mail-search-build.h b/src/lib-storage/mail-search-build.h
index 2fd7a6b625..bfddf15ad1 100644
--- a/src/lib-storage/mail-search-build.h
+++ b/src/lib-storage/mail-search-build.h
@@ -4,15 +4,16 @@
 #include "mail-search.h"
 #include "mail-search-register.h"
 
-struct imap_arg;
 struct mailbox;
 
 struct mail_search_build_context {
 	pool_t pool;
 	struct mail_search_register *reg;
+	struct mail_search_parser *parser;
 
 	struct mail_search_arg *parent;
-	const char *error;
+	/* error is either here or in parser */
+	const char *_error;
 };
 
 /* Start building a new search query. Use mail_search_args_unref() to
@@ -20,11 +21,9 @@ struct mail_search_build_context {
 struct mail_search_args *mail_search_build_init(void);
 
 /* Convert IMAP SEARCH command compatible parameters to mail_search_args. */
-int mail_search_build_from_imap_args(struct mail_search_register *reg,
-				     const struct imap_arg *imap_args,
-				     const char *charset,
-				     struct mail_search_args **args_r,
-				     const char **error_r);
+int mail_search_build(struct mail_search_register *reg,
+		      struct mail_search_parser *parser, const char *charset,
+		      struct mail_search_args **args_r, const char **error_r);
 
 /* Add SEARCH_ALL to search args. */
 void mail_search_build_add_all(struct mail_search_args *args);
@@ -32,23 +31,15 @@ void mail_search_build_add_all(struct mail_search_args *args);
 void mail_search_build_add_seqset(struct mail_search_args *args,
 				  uint32_t seq1, uint32_t seq2);
 
-int mail_search_build_next_astring(struct mail_search_build_context *ctx,
-				   const struct imap_arg **imap_args,
-				   const char **value_r);
-
 struct mail_search_arg *
 mail_search_build_new(struct mail_search_build_context *ctx,
 		      enum mail_search_arg_type type);
 struct mail_search_arg *
 mail_search_build_str(struct mail_search_build_context *ctx,
-		      const struct imap_arg **imap_args,
 		      enum mail_search_arg_type type);
-struct mail_search_arg *
-mail_search_build_next(struct mail_search_build_context *ctx,
-		       struct mail_search_arg *parent,
-		       const struct imap_arg **imap_args);
-struct mail_search_arg *
-mail_search_build_list(struct mail_search_build_context *ctx,
-		       const struct imap_arg *imap_args);
+/* Returns 0 if arg is returned, -1 if error. */
+int mail_search_build_key(struct mail_search_build_context *ctx,
+			  struct mail_search_arg *parent,
+			  struct mail_search_arg **arg_r);
 
 #endif
diff --git a/src/lib-storage/mail-search-parser-cmdline.c b/src/lib-storage/mail-search-parser-cmdline.c
new file mode 100644
index 0000000000..02cd23cefd
--- /dev/null
+++ b/src/lib-storage/mail-search-parser-cmdline.c
@@ -0,0 +1,98 @@
+/* Copyright (c) 2010 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "mail-search-parser-private.h"
+
+struct cmdline_mail_search_parser {
+	struct mail_search_parser parser;
+
+	const char *const *args;
+	unsigned int list_level;
+};
+
+static int cmdline_search_parse_key(struct mail_search_parser *_parser,
+				    const char **key_r)
+{
+	struct cmdline_mail_search_parser *parser =
+		(struct cmdline_mail_search_parser *)_parser;
+
+	if (parser->args[0] == NULL) {
+		if (parser->list_level != 0) {
+			_parser->error = "Missing ')'";
+			return -1;
+		}
+		return 0;
+	}
+
+	if (strcmp(parser->args[0], "(") == 0) {
+		parser->list_level++;
+		parser->args++;
+		*key_r = MAIL_SEARCH_PARSER_KEY_LIST;
+		return 1;
+	} else if (strcmp(parser->args[0], ")") == 0) {
+		if (parser->list_level == 0) {
+			_parser->error = "Unexpected ')'";
+			return -1;
+		}
+		parser->list_level--;
+		parser->args++;
+		*key_r = MAIL_SEARCH_PARSER_KEY_LIST;
+		return 0;
+	} else {
+		*key_r = parser->args[0];
+		parser->args++;
+		return 1;
+	}
+}
+
+static int cmdline_search_parse_string(struct mail_search_parser *_parser,
+				       const char **value_r)
+{
+	struct cmdline_mail_search_parser *parser =
+		(struct cmdline_mail_search_parser *)_parser;
+
+	if (parser->args[0] == NULL) {
+		_parser->error = "Missing parameter for search key";
+		return -1;
+	}
+	*value_r = parser->args[0];
+
+	parser->args++;
+	return 1;
+}
+
+static bool
+cmdline_search_parse_skip_next(struct mail_search_parser *_parser,
+			       const char *str)
+{
+	struct cmdline_mail_search_parser *parser =
+		(struct cmdline_mail_search_parser *)_parser;
+
+	if (parser->args[0] == NULL)
+		return FALSE;
+	if (strcasecmp(parser->args[0], str) != 0)
+		return FALSE;
+
+	parser->args++;
+	return TRUE;
+}
+
+static const struct mail_search_parser_vfuncs mail_search_parser_cmdline_vfuncs = {
+	cmdline_search_parse_key,
+	cmdline_search_parse_string,
+	cmdline_search_parse_skip_next
+};
+
+struct mail_search_parser *
+mail_search_parser_init_cmdline(const char *const args[])
+{
+	struct cmdline_mail_search_parser *parser;
+	pool_t pool;
+
+	pool = pool_alloconly_create("cmdline search parser", 1024);
+	parser = p_new(pool, struct cmdline_mail_search_parser, 1);
+	parser->parser.pool = pool;
+	parser->parser.v = mail_search_parser_cmdline_vfuncs;
+	parser->args = args;
+	return &parser->parser;
+}
diff --git a/src/lib-storage/mail-search-parser-imap.c b/src/lib-storage/mail-search-parser-imap.c
new file mode 100644
index 0000000000..342de8f27d
--- /dev/null
+++ b/src/lib-storage/mail-search-parser-imap.c
@@ -0,0 +1,122 @@
+/* Copyright (c) 2010 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "imap-arg.h"
+#include "mail-search-parser-private.h"
+
+struct imap_arg_stack {
+	struct imap_arg_stack *prev;
+
+	const struct imap_arg *args;
+};
+
+struct imap_mail_search_parser {
+	struct mail_search_parser parser;
+
+	struct imap_arg_stack root, *cur;
+};
+
+static int imap_search_parse_key(struct mail_search_parser *_parser,
+				 const char **key_r)
+{
+	struct imap_mail_search_parser *parser =
+		(struct imap_mail_search_parser *)_parser;
+	const struct imap_arg *arg = parser->cur->args;
+	struct imap_arg_stack *stack;
+
+	switch (arg->type) {
+	case IMAP_ARG_NIL:
+		_parser->error = "Unexpected NIL";
+		return -1;
+	case IMAP_ARG_ATOM:
+		*key_r = imap_arg_as_astring(arg);
+		break;
+	case IMAP_ARG_STRING:
+	case IMAP_ARG_LITERAL:
+		_parser->error = t_strconcat(
+			"Unexpected string as search key: ",
+			imap_arg_as_astring(arg), NULL);
+		return -1;
+	case IMAP_ARG_LIST:
+		stack = p_new(_parser->pool, struct imap_arg_stack, 1);
+		stack->prev = parser->cur;
+		stack->args = imap_arg_as_list(arg);
+		*key_r = MAIL_SEARCH_PARSER_KEY_LIST;
+		break;
+	case IMAP_ARG_EOL:
+		parser->cur = parser->cur->prev;
+		return 0;
+	case IMAP_ARG_LITERAL_SIZE:
+	case IMAP_ARG_LITERAL_SIZE_NONSYNC:
+		i_unreached();
+	}
+	parser->cur->args++;
+	return 1;
+}
+
+static int imap_search_parse_string(struct mail_search_parser *_parser,
+				    const char **value_r)
+{
+	struct imap_mail_search_parser *parser =
+		(struct imap_mail_search_parser *)_parser;
+	const struct imap_arg *arg = parser->cur->args;
+
+	switch (arg->type) {
+	case IMAP_ARG_NIL:
+		_parser->error = "Unexpected NIL";
+		return -1;
+	case IMAP_ARG_ATOM:
+	case IMAP_ARG_STRING:
+	case IMAP_ARG_LITERAL:
+		*value_r = imap_arg_as_astring(arg);
+		break;
+	case IMAP_ARG_LIST:
+		_parser->error = "Unexpected (";
+		return -1;
+	case IMAP_ARG_EOL:
+		_parser->error = "Missing parameter for search key";
+		return -1;
+	case IMAP_ARG_LITERAL_SIZE:
+	case IMAP_ARG_LITERAL_SIZE_NONSYNC:
+		i_unreached();
+	}
+	parser->cur->args++;
+	return 1;
+}
+
+static bool
+imap_search_parse_skip_next(struct mail_search_parser *_parser, const char *str)
+{
+	struct imap_mail_search_parser *parser =
+		(struct imap_mail_search_parser *)_parser;
+	const char *arg;
+
+	if (!imap_arg_get_astring(parser->cur->args, &arg))
+		return FALSE;
+	if (strcasecmp(arg, str) != 0)
+		return FALSE;
+
+	parser->cur->args++;
+	return TRUE;
+}
+
+static const struct mail_search_parser_vfuncs mail_search_parser_imap_vfuncs = {
+	imap_search_parse_key,
+	imap_search_parse_string,
+	imap_search_parse_skip_next
+};
+
+struct mail_search_parser *
+mail_search_parser_init_imap(const struct imap_arg *args)
+{
+	struct imap_mail_search_parser *parser;
+	pool_t pool;
+
+	pool = pool_alloconly_create("imap search parser", 1024);
+	parser = p_new(pool, struct imap_mail_search_parser, 1);
+	parser->parser.pool = pool;
+	parser->parser.v = mail_search_parser_imap_vfuncs;
+	parser->root.args = args;
+	parser->cur = &parser->root;
+	return &parser->parser;
+}
diff --git a/src/lib-storage/mail-search-parser-private.h b/src/lib-storage/mail-search-parser-private.h
new file mode 100644
index 0000000000..1e7af1f2e5
--- /dev/null
+++ b/src/lib-storage/mail-search-parser-private.h
@@ -0,0 +1,22 @@
+#ifndef MAIL_SEARCH_PARSER_PRIVATE_H
+#define MAIL_SEARCH_PARSER_PRIVATE_H
+
+#include "mail-search-parser.h"
+
+struct mail_search_parser_vfuncs {
+	int (*parse_key)(struct mail_search_parser *parser, const char **key_r);
+	int (*parse_string)(struct mail_search_parser *parser,
+			    const char **value_r);
+	bool (*parse_skip_next)(struct mail_search_parser *parser,
+				const char *str);
+};
+
+struct mail_search_parser {
+	struct mail_search_parser_vfuncs v;
+
+	pool_t pool;
+	const char *cur_key;
+	const char *error;
+};
+
+#endif
diff --git a/src/lib-storage/mail-search-parser.c b/src/lib-storage/mail-search-parser.c
new file mode 100644
index 0000000000..7aebb8f0e9
--- /dev/null
+++ b/src/lib-storage/mail-search-parser.c
@@ -0,0 +1,49 @@
+/* Copyright (c) 2010 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "mail-search-parser-private.h"
+
+void mail_search_parser_deinit(struct mail_search_parser **_parser)
+{
+	struct mail_search_parser *parser = *_parser;
+
+	*_parser = NULL;
+	pool_unref(&parser->pool);
+}
+
+int mail_search_parse_key(struct mail_search_parser *parser,
+			  const char **key_r)
+{
+	int ret;
+
+	if ((ret = parser->v.parse_key(parser, key_r)) <= 0)
+		return ret;
+
+	parser->cur_key = *key_r;
+	return 1;
+}
+
+int mail_search_parse_string(struct mail_search_parser *parser,
+			     const char **value_r)
+{
+	int ret;
+
+	ret = parser->v.parse_string(parser, value_r);
+	if (ret < 0 && parser->cur_key != NULL) {
+		parser->error = p_strdup_printf(parser->pool,
+			"%s (for search key: %s)",
+			parser->error, t_str_ucase(parser->cur_key));
+	}
+	return ret;
+}
+
+bool mail_search_parse_skip_next(struct mail_search_parser *parser,
+				 const char *str)
+{
+	return parser->v.parse_skip_next(parser, str);
+}
+
+const char *mail_search_parser_get_error(struct mail_search_parser *parser)
+{
+	return parser->error;
+}
diff --git a/src/lib-storage/mail-search-parser.h b/src/lib-storage/mail-search-parser.h
new file mode 100644
index 0000000000..0535587c4c
--- /dev/null
+++ b/src/lib-storage/mail-search-parser.h
@@ -0,0 +1,34 @@
+#ifndef MAIL_SEARCH_PARSER_H
+#define MAIL_SEARCH_PARSER_H
+
+#define MAIL_SEARCH_PARSER_KEY_LIST "("
+
+struct imap_arg;
+
+/* Build a parser parsing the given imap args. NOTE: args must not be freed
+   until this parser is destroyed. */
+struct mail_search_parser *
+mail_search_parser_init_imap(const struct imap_arg *args);
+/* Build a parser parsing the given command line args. */
+struct mail_search_parser *
+mail_search_parser_init_cmdline(const char *const args[]);
+
+void mail_search_parser_deinit(struct mail_search_parser **parser);
+
+/* Key is set to the next search key, or MAIL_SEARCH_PARSER_KEY_LIST for
+   beginning of a list. Returns 1 if ok, 0 if no more keys in this
+   list/query, -1 if parsing error. */
+int mail_search_parse_key(struct mail_search_parser *parser,
+			  const char **key_r);
+/* Get the next string. Returns 0 if ok, -1 if parsing error. */
+int mail_search_parse_string(struct mail_search_parser *parser,
+			     const char **value_r);
+/* If next parameter equals to the given string case-insensitively, skip over
+   it and return TRUE. Otherwise do nothing and return FALSE. */
+bool mail_search_parse_skip_next(struct mail_search_parser *parser,
+				 const char *str);
+
+/* Returns the reason string for parsing error. */
+const char *mail_search_parser_get_error(struct mail_search_parser *parser);
+
+#endif
diff --git a/src/lib-storage/mail-search-register-human.c b/src/lib-storage/mail-search-register-human.c
index c652d10a63..6f2b5aca93 100644
--- a/src/lib-storage/mail-search-register-human.c
+++ b/src/lib-storage/mail-search-register-human.c
@@ -6,6 +6,7 @@
 #include "settings-parser.h"
 #include "imap-date.h"
 #include "mail-search-register.h"
+#include "mail-search-parser.h"
 #include "mail-search-build.h"
 
 #include <time.h>
@@ -14,17 +15,19 @@
 struct mail_search_register *mail_search_register_human;
 
 static struct mail_search_arg *
-human_search_or(struct mail_search_build_context *ctx,
-		const struct imap_arg **imap_args)
+human_search_or(struct mail_search_build_context *ctx)
 {
+	struct mail_search_arg *sarg;
+
 	/* this changes the parent arg to be an OR block instead of AND block */
 	ctx->parent->type = SEARCH_OR;
-	return mail_search_build_next(ctx, ctx->parent, imap_args);
+	if (mail_search_build_key(ctx, ctx->parent, &sarg) < 0)
+		return NULL;
+	return sarg;
 }
 
 static struct mail_search_arg *
 arg_new_human_date(struct mail_search_build_context *ctx,
-		   const struct imap_arg **imap_args,
 		   enum mail_search_arg_type type,
 		   enum mail_search_date_type date_type)
 {
@@ -35,7 +38,7 @@ arg_new_human_date(struct mail_search_build_context *ctx,
 	int tz;
 
 	sarg = mail_search_build_new(ctx, type);
-	if (mail_search_build_next_astring(ctx, imap_args, &value) < 0)
+	if (mail_search_parse_string(ctx->parser, &value) < 0)
 		return NULL;
 
 	/* a) yyyy-mm-dd
@@ -61,7 +64,7 @@ arg_new_human_date(struct mail_search_build_context *ctx,
 	sarg->value.search_flags = MAIL_SEARCH_ARG_FLAG_USE_TZ;
 
 	if (sarg->value.time == (time_t)-1) {
-		ctx->error = p_strconcat(ctx->pool,
+		ctx->_error = p_strconcat(ctx->pool,
 			"Invalid search date parameter: ", value, NULL);
 		return NULL;
 	}
@@ -71,10 +74,9 @@ arg_new_human_date(struct mail_search_build_context *ctx,
 
 #define CALLBACK_DATE(_func, _type, _date_type) \
 static struct mail_search_arg *\
-human_search_##_func(struct mail_search_build_context *ctx, \
-                     const struct imap_arg **imap_args) \
+human_search_##_func(struct mail_search_build_context *ctx) \
 { \
-	return arg_new_human_date(ctx, imap_args, _type, _date_type); \
+	return arg_new_human_date(ctx, _type, _date_type); \
 }
 CALLBACK_DATE(before, SEARCH_BEFORE, MAIL_SEARCH_DATE_TYPE_RECEIVED);
 CALLBACK_DATE(on, SEARCH_ON, MAIL_SEARCH_DATE_TYPE_RECEIVED);
@@ -90,49 +92,44 @@ CALLBACK_DATE(savedsince, SEARCH_SINCE, MAIL_SEARCH_DATE_TYPE_SAVED);
 
 static struct mail_search_arg *
 arg_new_human_size(struct mail_search_build_context *ctx,
-		   const struct imap_arg **imap_args,
 		   enum mail_search_arg_type type)
 {
 	struct mail_search_arg *sarg;
 	const char *value, *error;
 
 	sarg = mail_search_build_new(ctx, type);
-	if (mail_search_build_next_astring(ctx, imap_args, &value) < 0)
+	if (mail_search_parse_string(ctx->parser, &value) < 0)
 		return NULL;
 
 	if (settings_get_size(value, &sarg->value.size, &error) < 0) {
-		ctx->error = p_strdup(ctx->pool, error);
+		ctx->_error = p_strdup(ctx->pool, error);
 		return NULL;
 	}
 	return sarg;
 }
 
 static struct mail_search_arg *
-human_search_larger(struct mail_search_build_context *ctx,
-		    const struct imap_arg **imap_args)
+human_search_larger(struct mail_search_build_context *ctx)
 { 
-	return arg_new_human_size(ctx, imap_args, SEARCH_LARGER);
+	return arg_new_human_size(ctx, SEARCH_LARGER);
 }
 
 static struct mail_search_arg *
-human_search_smaller(struct mail_search_build_context *ctx,
-		     const struct imap_arg **imap_args)
+human_search_smaller(struct mail_search_build_context *ctx)
 { 
-	return arg_new_human_size(ctx, imap_args, SEARCH_SMALLER);
+	return arg_new_human_size(ctx, SEARCH_SMALLER);
 }
 
 static struct mail_search_arg *
-human_search_guid(struct mail_search_build_context *ctx,
-		  const struct imap_arg **imap_args)
+human_search_guid(struct mail_search_build_context *ctx)
 {
-	return mail_search_build_str(ctx, imap_args, SEARCH_GUID);
+	return mail_search_build_str(ctx, SEARCH_GUID);
 }
 
 static struct mail_search_arg *
-human_search_mailbox(struct mail_search_build_context *ctx,
-		     const struct imap_arg **imap_args)
+human_search_mailbox(struct mail_search_build_context *ctx)
 {
-	return mail_search_build_str(ctx, imap_args, SEARCH_MAILBOX);
+	return mail_search_build_str(ctx, SEARCH_MAILBOX);
 }
 
 static const struct mail_search_register_arg human_register_args[] = {
diff --git a/src/lib-storage/mail-search-register-imap.c b/src/lib-storage/mail-search-register-imap.c
index 233ba0cbca..49a5f78af7 100644
--- a/src/lib-storage/mail-search-register-imap.c
+++ b/src/lib-storage/mail-search-register-imap.c
@@ -2,11 +2,12 @@
 
 #include "lib.h"
 #include "ioloop.h"
+#include "array.h"
 #include "imap-date.h"
-#include "imap-arg.h"
 #include "imap-seqset.h"
 #include "imap-util.h"
 #include "mail-search-register.h"
+#include "mail-search-parser.h"
 #include "mail-search-build.h"
 
 #include <stdlib.h>
@@ -15,8 +16,7 @@ struct mail_search_register *mail_search_register_imap;
 
 static struct mail_search_arg *
 imap_search_fallback(struct mail_search_build_context *ctx,
-		     const char *key,
-		     const struct imap_arg **imap_args ATTR_UNUSED)
+		     const char *key)
 {
 	struct mail_search_arg *sarg;
 
@@ -25,30 +25,29 @@ imap_search_fallback(struct mail_search_build_context *ctx,
 		sarg = mail_search_build_new(ctx, SEARCH_SEQSET);
 		p_array_init(&sarg->value.seqset, ctx->pool, 16);
 		if (imap_seq_set_parse(key, &sarg->value.seqset) < 0) {
-			ctx->error = "Invalid messageset";
+			ctx->_error = "Invalid messageset";
 			return NULL;
 		}
 		return sarg;
 	}
-	ctx->error = p_strconcat(ctx->pool, "Unknown argument ", key, NULL);
+	ctx->_error = p_strconcat(ctx->pool, "Unknown argument ", key, NULL);
 	return NULL;
 }
 
 static struct mail_search_arg *
-imap_search_not(struct mail_search_build_context *ctx,
-		const struct imap_arg **imap_args)
+imap_search_not(struct mail_search_build_context *ctx)
 {
 	struct mail_search_arg *sarg;
 
-	sarg = mail_search_build_next(ctx, ctx->parent, imap_args);
-	if (sarg != NULL)
-		sarg->not = !sarg->not;
+	if (mail_search_build_key(ctx, ctx->parent, &sarg) < 0)
+		return NULL;
+
+	sarg->not = !sarg->not;
 	return sarg;
 }
 
 static struct mail_search_arg *
-imap_search_or(struct mail_search_build_context *ctx,
-	       const struct imap_arg **imap_args)
+imap_search_or(struct mail_search_build_context *ctx)
 {
 	struct mail_search_arg *sarg, **subargs;
 
@@ -56,48 +55,39 @@ imap_search_or(struct mail_search_build_context *ctx,
 	sarg = mail_search_build_new(ctx, SEARCH_OR);
 
 	subargs = &sarg->value.subargs;
-	for (;;) {
-		*subargs = mail_search_build_next(ctx, sarg, imap_args);
-		if (*subargs == NULL)
+	do {
+		if (mail_search_build_key(ctx, sarg, subargs) < 0)
 			return NULL;
 		subargs = &(*subargs)->next;
 
 		/* <key> OR <key> OR ... <key> - put them all
 		   under one SEARCH_OR list. */
-		if (!imap_arg_atom_equals(*imap_args, "OR"))
-			break;
+	} while (mail_search_parse_skip_next(ctx->parser, "OR"));
 
-		*imap_args += 1;
-	}
-
-	*subargs = mail_search_build_next(ctx, sarg, imap_args);
-	if (*subargs == NULL)
+	if (mail_search_build_key(ctx, sarg, subargs) < 0)
 		return NULL;
 	return sarg;
 }
 
 #define CALLBACK_STR(_func, _type) \
 static struct mail_search_arg *\
-imap_search_##_func(struct mail_search_build_context *ctx, \
-                    const struct imap_arg **imap_args) \
+imap_search_##_func(struct mail_search_build_context *ctx) \
 { \
-	return mail_search_build_str(ctx, imap_args, _type); \
+	return mail_search_build_str(ctx, _type); \
 }
 static struct mail_search_arg *
-imap_search_all(struct mail_search_build_context *ctx,
-		const struct imap_arg **imap_args ATTR_UNUSED)
+imap_search_all(struct mail_search_build_context *ctx)
 { 
 	return mail_search_build_new(ctx, SEARCH_ALL);
 }
 
 static struct mail_search_arg *
-imap_search_uid(struct mail_search_build_context *ctx,
-		const struct imap_arg **imap_args ATTR_UNUSED)
+imap_search_uid(struct mail_search_build_context *ctx)
 {
 	struct mail_search_arg *sarg;
 
 	/* <message set> */
-	sarg = mail_search_build_str(ctx, imap_args, SEARCH_UIDSET);
+	sarg = mail_search_build_str(ctx, SEARCH_UIDSET);
 	if (sarg == NULL)
 		return NULL;
 
@@ -107,7 +97,7 @@ imap_search_uid(struct mail_search_build_context *ctx,
 	} else {
 		if (imap_seq_set_parse(sarg->value.str,
 				       &sarg->value.seqset) < 0) {
-			ctx->error = "Invalid UID messageset";
+			ctx->_error = "Invalid UID messageset";
 			return NULL;
 		}
 	}
@@ -116,8 +106,7 @@ imap_search_uid(struct mail_search_build_context *ctx,
 
 #define CALLBACK_FLAG(_func, _flag, _not) \
 static struct mail_search_arg *\
-imap_search_##_func(struct mail_search_build_context *ctx, \
-                    const struct imap_arg **imap_args ATTR_UNUSED) \
+imap_search_##_func(struct mail_search_build_context *ctx) \
 { \
 	struct mail_search_arg *sarg; \
 	sarg = mail_search_build_new(ctx, SEARCH_FLAGS); \
@@ -139,27 +128,25 @@ CALLBACK_FLAG(recent, MAIL_RECENT, FALSE);
 CALLBACK_FLAG(old, MAIL_RECENT, TRUE);
 
 static struct mail_search_arg *
-imap_search_new(struct mail_search_build_context *ctx,
-		const struct imap_arg **imap_args ATTR_UNUSED)
+imap_search_new(struct mail_search_build_context *ctx)
 {
 	struct mail_search_arg *sarg;
 
 	/* NEW == (RECENT UNSEEN) */
 	sarg = mail_search_build_new(ctx, SEARCH_SUB);
-	sarg->value.subargs = imap_search_recent(ctx, NULL);
-	sarg->value.subargs->next = imap_search_unseen(ctx, NULL);
+	sarg->value.subargs = imap_search_recent(ctx);
+	sarg->value.subargs->next = imap_search_unseen(ctx);
 	return sarg;
 }
 
 CALLBACK_STR(keyword, SEARCH_KEYWORDS);
 
 static struct mail_search_arg *
-imap_search_unkeyword(struct mail_search_build_context *ctx,
-		      const struct imap_arg **imap_args)
+imap_search_unkeyword(struct mail_search_build_context *ctx)
 {
 	struct mail_search_arg *sarg;
 
-	sarg = imap_search_keyword(ctx, imap_args);
+	sarg = imap_search_keyword(ctx);
 	if (sarg != NULL)
 		sarg->not = TRUE;
 	return sarg;
@@ -167,7 +154,6 @@ imap_search_unkeyword(struct mail_search_build_context *ctx,
 
 static struct mail_search_arg *
 arg_new_date(struct mail_search_build_context *ctx,
-	     const struct imap_arg **imap_args,
 	     enum mail_search_arg_type type,
 	     enum mail_search_date_type date_type)
 {
@@ -175,10 +161,10 @@ arg_new_date(struct mail_search_build_context *ctx,
 	const char *value;
 
 	sarg = mail_search_build_new(ctx, type);
-	if (mail_search_build_next_astring(ctx, imap_args, &value) < 0)
+	if (mail_search_parse_string(ctx->parser, &value) < 0)
 		return NULL;
 	if (!imap_parse_date(value, &sarg->value.time)) {
-		ctx->error = "Invalid search date parameter";
+		ctx->_error = "Invalid search date parameter";
 		return NULL;
 	}
 	sarg->value.date_type = date_type;
@@ -187,10 +173,9 @@ arg_new_date(struct mail_search_build_context *ctx,
 
 #define CALLBACK_DATE(_func, _type, _date_type) \
 static struct mail_search_arg *\
-imap_search_##_func(struct mail_search_build_context *ctx, \
-                    const struct imap_arg **imap_args) \
+imap_search_##_func(struct mail_search_build_context *ctx) \
 { \
-	return arg_new_date(ctx, imap_args, _type, _date_type); \
+	return arg_new_date(ctx, _type, _date_type); \
 }
 CALLBACK_DATE(before, SEARCH_BEFORE, MAIL_SEARCH_DATE_TYPE_RECEIVED);
 CALLBACK_DATE(on, SEARCH_ON, MAIL_SEARCH_DATE_TYPE_RECEIVED);
@@ -206,47 +191,43 @@ CALLBACK_DATE(x_savedsince, SEARCH_SINCE, MAIL_SEARCH_DATE_TYPE_SAVED);
 
 static struct mail_search_arg *
 arg_new_size(struct mail_search_build_context *ctx,
-	     const struct imap_arg **imap_args,
 	     enum mail_search_arg_type type)
 {
 	struct mail_search_arg *sarg;
 	const char *value;
 
 	sarg = mail_search_build_new(ctx, type);
-	if (mail_search_build_next_astring(ctx, imap_args, &value) < 0)
+	if (mail_search_parse_string(ctx->parser, &value) < 0)
 		return NULL;
 
 	if (str_to_uoff(value, &sarg->value.size) < 0) {
-		ctx->error = "Invalid search size parameter";
+		ctx->_error = "Invalid search size parameter";
 		return NULL;
 	}
 	return sarg;
 }
 
 static struct mail_search_arg *
-imap_search_larger(struct mail_search_build_context *ctx,
-		   const struct imap_arg **imap_args)
+imap_search_larger(struct mail_search_build_context *ctx)
 { 
-	return arg_new_size(ctx, imap_args, SEARCH_LARGER);
+	return arg_new_size(ctx, SEARCH_LARGER);
 }
 
 static struct mail_search_arg *
-imap_search_smaller(struct mail_search_build_context *ctx,
-		    const struct imap_arg **imap_args)
+imap_search_smaller(struct mail_search_build_context *ctx)
 { 
-	return arg_new_size(ctx, imap_args, SEARCH_SMALLER);
+	return arg_new_size(ctx, SEARCH_SMALLER);
 }
 
 static struct mail_search_arg *
 arg_new_header(struct mail_search_build_context *ctx,
-	       const struct imap_arg **imap_args,
 	       enum mail_search_arg_type type, const char *hdr_name)
 {
 	struct mail_search_arg *sarg;
 	const char *value;
 
 	sarg = mail_search_build_new(ctx, type);
-	if (mail_search_build_next_astring(ctx, imap_args, &value) < 0)
+	if (mail_search_parse_string(ctx->parser, &value) < 0)
 		return NULL;
 
 	sarg->hdr_field_name = p_strdup(ctx->pool, hdr_name);
@@ -256,10 +237,9 @@ arg_new_header(struct mail_search_build_context *ctx,
 
 #define CALLBACK_HDR(_name, _type) \
 static struct mail_search_arg *\
-imap_search_##_name(struct mail_search_build_context *ctx, \
-                    const struct imap_arg **imap_args) \
+imap_search_##_name(struct mail_search_build_context *ctx) \
 { \
-	return arg_new_header(ctx, imap_args, _type, #_name); \
+	return arg_new_header(ctx, _type, #_name); \
 }
 CALLBACK_HDR(bcc, SEARCH_HEADER_ADDRESS);
 CALLBACK_HDR(cc, SEARCH_HEADER_ADDRESS);
@@ -268,38 +248,26 @@ CALLBACK_HDR(to, SEARCH_HEADER_ADDRESS);
 CALLBACK_HDR(subject, SEARCH_HEADER_COMPRESS_LWSP);
 
 static struct mail_search_arg *
-imap_search_header(struct mail_search_build_context *ctx,
-		   const struct imap_arg **imap_args)
+imap_search_header(struct mail_search_build_context *ctx)
 {
-	const char *value;
+	const char *hdr_name;
 
-	/* <field-name> <string> */
-	if (IMAP_ARG_IS_EOL(*imap_args)) {
-		ctx->error = "Missing parameter for HEADER";
-		return NULL;
-	}
-	if (!imap_arg_get_astring(*imap_args, &value)) {
-		ctx->error = "Invalid parameter for HEADER";
+	/* <hdr-name> <string> */
+	if (mail_search_parse_string(ctx->parser, &hdr_name) < 0)
 		return NULL;
-	}
 
-	*imap_args += 1;
-	return arg_new_header(ctx, imap_args, SEARCH_HEADER,
-			      t_str_ucase(value));
+	return arg_new_header(ctx, SEARCH_HEADER, t_str_ucase(hdr_name));
 }
 
 #define CALLBACK_BODY(_func, _type) \
 static struct mail_search_arg *\
-imap_search_##_func(struct mail_search_build_context *ctx, \
-                    const struct imap_arg **imap_args) \
+imap_search_##_func(struct mail_search_build_context *ctx) \
 { \
-	const char *value; \
-	if (imap_arg_get_astring(*imap_args, &value) && *value == '\0') { \
+	if (mail_search_parse_skip_next(ctx->parser, "")) { \
 		/* optimization: BODY "" matches everything */ \
-		*imap_args += 1; \
 		return mail_search_build_new(ctx, SEARCH_ALL); \
 	} \
-	return mail_search_build_str(ctx, imap_args, _type); \
+	return mail_search_build_str(ctx, _type); \
 }
 CALLBACK_BODY(body, SEARCH_BODY);
 CALLBACK_BODY(text, SEARCH_TEXT);
@@ -308,7 +276,6 @@ CALLBACK_BODY(x_text_fast, SEARCH_TEXT_FAST);
 
 static struct mail_search_arg *
 arg_new_interval(struct mail_search_build_context *ctx,
-		 const struct imap_arg **imap_args,
 		 enum mail_search_arg_type type)
 {
 	struct mail_search_arg *sarg;
@@ -316,11 +283,11 @@ arg_new_interval(struct mail_search_build_context *ctx,
 	uint32_t interval;
 
 	sarg = mail_search_build_new(ctx, type);
-	if (mail_search_build_next_astring(ctx, imap_args, &value) < 0)
+	if (mail_search_parse_string(ctx->parser, &value) < 0)
 		return NULL;
 
 	if (str_to_uint32(value, &interval) < 0 || interval == 0) {
-		ctx->error = "Invalid search interval parameter";
+		ctx->_error = "Invalid search interval parameter";
 		return NULL;
 	}
 	sarg->value.search_flags = MAIL_SEARCH_ARG_FLAG_USE_TZ;
@@ -329,102 +296,102 @@ arg_new_interval(struct mail_search_build_context *ctx,
 }
 
 static struct mail_search_arg *
-imap_search_older(struct mail_search_build_context *ctx,
-		  const struct imap_arg **imap_args)
+imap_search_older(struct mail_search_build_context *ctx)
 {
 	struct mail_search_arg *sarg;
 
-	sarg = arg_new_interval(ctx, imap_args, SEARCH_BEFORE);
+	sarg = arg_new_interval(ctx, SEARCH_BEFORE);
 	/* we need to match also equal, but SEARCH_BEFORE compares with "<" */
 	sarg->value.time++;
 	return sarg;
 }
 
 static struct mail_search_arg *
-imap_search_younger(struct mail_search_build_context *ctx,
-		    const struct imap_arg **imap_args)
+imap_search_younger(struct mail_search_build_context *ctx)
 {
-	return arg_new_interval(ctx, imap_args, SEARCH_SINCE);
+	return arg_new_interval(ctx, SEARCH_SINCE);
 }
 
 static int
-arg_modseq_set_name(struct mail_search_build_context *ctx,
-		    struct mail_search_arg *sarg, const char *name)
+arg_modseq_set_type(struct mail_search_build_context *ctx,
+		    struct mail_search_modseq *modseq, const char *name)
 {
-	name = t_str_lcase(name);
-	if (strncmp(name, "/flags/", 7) != 0) {
-		ctx->error = "Invalid MODSEQ entry";
+	if (strcasecmp(name, "all") == 0)
+		modseq->type = MAIL_SEARCH_MODSEQ_TYPE_ANY;
+	else if (strcasecmp(name, "priv") == 0)
+		modseq->type = MAIL_SEARCH_MODSEQ_TYPE_PRIVATE;
+	else if (strcasecmp(name, "shared") == 0)
+		modseq->type = MAIL_SEARCH_MODSEQ_TYPE_SHARED;
+	else {
+		ctx->_error = "Invalid MODSEQ type";
 		return -1;
 	}
+	return 0;
+}
+
+static int
+arg_modseq_set_ext(struct mail_search_build_context *ctx,
+		   struct mail_search_arg *sarg, const char *name)
+{
+	const char *value;
+
+	name = t_str_lcase(name);
+	if (strncmp(name, "/flags/", 7) != 0)
+		return 0;
 	name += 7;
 
+	/* set name */
 	if (*name == '\\') {
 		/* system flag */
 		sarg->value.flags = imap_parse_system_flag(name);
 		if (sarg->value.flags == 0 ||
 		    sarg->value.flags == MAIL_RECENT) {
-			ctx->error = "Invalid MODSEQ system flag";
+			ctx->_error = "Invalid MODSEQ system flag";
 			return -1;
 		}
-		return 0;
+	} else {
+		sarg->value.str = p_strdup(ctx->pool, name);
 	}
-	sarg->value.str = p_strdup(ctx->pool, name);
-	return 0;
-}
 
-static int
-arg_modseq_set_type(struct mail_search_build_context *ctx,
-		    struct mail_search_modseq *modseq, const char *name)
-{
-	if (strcasecmp(name, "all") == 0)
-		modseq->type = MAIL_SEARCH_MODSEQ_TYPE_ANY;
-	else if (strcasecmp(name, "priv") == 0)
-		modseq->type = MAIL_SEARCH_MODSEQ_TYPE_PRIVATE;
-	else if (strcasecmp(name, "shared") == 0)
-		modseq->type = MAIL_SEARCH_MODSEQ_TYPE_SHARED;
-	else {
-		ctx->error = "Invalid MODSEQ type";
+	/* set type */
+	if (mail_search_parse_string(ctx->parser, &value) < 0)
 		return -1;
-	}
-	return 0;
+	if (arg_modseq_set_type(ctx, sarg->value.modseq, value) < 0)
+		return -1;
+	return 1;
 }
 
 static struct mail_search_arg *
-imap_search_modseq(struct mail_search_build_context *ctx,
-		   const struct imap_arg **imap_args)
+imap_search_modseq(struct mail_search_build_context *ctx)
 {
 	struct mail_search_arg *sarg;
 	const char *value;
+	int ret;
 
 	/* [<name> <type>] <modseq> */
 	sarg = mail_search_build_new(ctx, SEARCH_MODSEQ);
-	if (mail_search_build_next_astring(ctx, imap_args, &value) < 0)
-		return NULL;
-
 	sarg->value.modseq = p_new(ctx->pool, struct mail_search_modseq, 1);
-	if ((*imap_args)[-1].type == IMAP_ARG_STRING) {
-		/* <name> <type> */
-		if (arg_modseq_set_name(ctx, sarg, value) < 0)
-			return NULL;
 
-		if (mail_search_build_next_astring(ctx, imap_args, &value) < 0)
-			return NULL;
-		if (arg_modseq_set_type(ctx, sarg->value.modseq, value) < 0)
-			return NULL;
+	if (mail_search_parse_string(ctx->parser, &value) < 0)
+		return NULL;
 
-		if (mail_search_build_next_astring(ctx, imap_args, &value) < 0)
+	if ((ret = arg_modseq_set_ext(ctx, sarg, value)) < 0)
+		return NULL;
+	if (ret > 0) {
+		/* extension data used */
+		if (mail_search_parse_string(ctx->parser, &value) < 0)
 			return NULL;
 	}
+
 	if (str_to_uint64(value, &sarg->value.modseq->modseq) < 0) {
-		ctx->error = "Invalid MODSEQ value";
+		ctx->_error = "Invalid MODSEQ value";
 		return NULL;
 	}
 	return sarg;
 }
 
 static struct mail_search_arg *
-imap_search_last_result(struct mail_search_build_context *ctx,
-			const struct imap_arg **imap_args ATTR_UNUSED)
+imap_search_last_result(struct mail_search_build_context *ctx)
 {
 	struct mail_search_arg *sarg;
 
@@ -436,8 +403,7 @@ imap_search_last_result(struct mail_search_build_context *ctx,
 }
 
 static struct mail_search_arg *
-imap_search_inthread(struct mail_search_build_context *ctx,
-		     const struct imap_arg **imap_args)
+imap_search_inthread(struct mail_search_build_context *ctx)
 {
 	struct mail_search_arg *sarg;
 
@@ -445,21 +411,16 @@ imap_search_inthread(struct mail_search_build_context *ctx,
 	enum mail_thread_type thread_type;
 	const char *algorithm;
 
-	if (!imap_arg_get_atom(*imap_args, &algorithm)) {
-		ctx->error = "Invalid parameter for INTHREAD";
+	if (mail_search_parse_string(ctx->parser, &algorithm) < 0)
 		return NULL;
-	}
-
 	if (!mail_thread_type_parse(algorithm, &thread_type)) {
-		ctx->error = "Unknown thread algorithm";
+		ctx->_error = "Unknown thread algorithm";
 		return NULL;
 	}
-	*imap_args += 1;
 
 	sarg = mail_search_build_new(ctx, SEARCH_INTHREAD);
 	sarg->value.thread_type = thread_type;
-	sarg->value.subargs = mail_search_build_next(ctx, sarg, imap_args);
-	if (sarg->value.subargs == NULL)
+	if (mail_search_build_key(ctx, sarg, &sarg->value.subargs) < 0)
 		return NULL;
 	return sarg;
 }
diff --git a/src/lib-storage/mail-search-register.h b/src/lib-storage/mail-search-register.h
index b6e0dbb0ce..e5446d43b6 100644
--- a/src/lib-storage/mail-search-register.h
+++ b/src/lib-storage/mail-search-register.h
@@ -1,18 +1,15 @@
 #ifndef MAIL_SEARCH_REGISTER_H
 #define MAIL_SEARCH_REGISTER_H
 
-struct imap_arg;
 struct mail_search_arg;
 struct mail_search_build_context;
 
 struct mail_search_register_arg {
 	const char *key;
 
-	/* read wanted parameters from imap_arg, returns parsed arg or NULL if
-	   error. error message is set to ctx. */
+	/* returns parsed arg or NULL if error. error message is set to ctx. */
 	struct mail_search_arg *
-		(*build)(struct mail_search_build_context *ctx,
-			 const struct imap_arg **imap_args);
+		(*build)(struct mail_search_build_context *ctx);
 };
 
 extern struct mail_search_register *mail_search_register_imap;
@@ -20,8 +17,7 @@ extern struct mail_search_register *mail_search_register_human;
 
 typedef struct mail_search_arg *
 mail_search_register_fallback_t(struct mail_search_build_context *ctx,
-				const char *key,
-				const struct imap_arg **imap_args);
+				const char *key);
 
 struct mail_search_register *mail_search_register_init(void);
 void mail_search_register_deinit(struct mail_search_register **reg);
diff --git a/src/plugins/virtual/virtual-config.c b/src/plugins/virtual/virtual-config.c
index a03a34616d..c39d7bab10 100644
--- a/src/plugins/virtual/virtual-config.c
+++ b/src/plugins/virtual/virtual-config.c
@@ -8,6 +8,7 @@
 #include "imap-parser.h"
 #include "imap-match.h"
 #include "mail-search-build.h"
+#include "mail-search-parser.h"
 #include "virtual-storage.h"
 #include "virtual-plugin.h"
 
@@ -30,8 +31,9 @@ static struct mail_search_args *
 virtual_search_args_parse(const string_t *rule, const char **error_r)
 {
 	struct istream *input;
-	struct imap_parser *parser;
+	struct imap_parser *imap_parser;
 	const struct imap_arg *args;
+	struct mail_search_parser *parser;
 	struct mail_search_args *sargs;
 	bool fatal;
 	int ret;
@@ -45,17 +47,20 @@ virtual_search_args_parse(const string_t *rule, const char **error_r)
 	input = i_stream_create_from_data(str_data(rule), str_len(rule));
 	(void)i_stream_read(input);
 
-	parser = imap_parser_create(input, NULL, (size_t)-1);
-	ret = imap_parser_finish_line(parser, 0,  0, &args);
+	imap_parser = imap_parser_create(input, NULL, (size_t)-1);
+	ret = imap_parser_finish_line(imap_parser, 0,  0, &args);
 	if (ret < 0) {
 		sargs = NULL;
-		*error_r = t_strdup(imap_parser_get_error(parser, &fatal));
-	} else if (mail_search_build_from_imap_args(mail_search_register_imap,
-						    args, "UTF-8", &sargs,
-						    error_r) < 0)
-		sargs = NULL;
+		*error_r = t_strdup(imap_parser_get_error(imap_parser, &fatal));
+	} else {
+		parser = mail_search_parser_init_imap(args);
+		if (mail_search_build(mail_search_register_imap, parser, "UTF-8",
+				      &sargs, error_r) < 0)
+			sargs = NULL;
+		mail_search_parser_deinit(&parser);
+	}
 
-	imap_parser_destroy(&parser);
+	imap_parser_destroy(&imap_parser);
 	i_stream_destroy(&input);
 	return sargs;
 }