simplify parsing responses with multiple IMAP lists

the callbacks took the current parsing position only to pass it on to
the next list parse. so instead, store it in the state, and have a
separate function for continuation.

src/drv_imap.c

@@ -73,7 +73,7 @@ typedef union imap_store imap_store_t;
 
 typedef struct {
 	list_t *head, **stack[MAX_LIST_DEPTH];
-	int (*callback)( imap_store_t *ctx, list_t *list, char *cmd );
+	int (*callback)( imap_store_t *ctx, list_t *list );
 	int level, need_bytes;
 } parse_list_state_t;
 
@@ -109,6 +109,7 @@ union imap_store {
 		uint caps;  // CAPABILITY results
 		string_list_t *auth_mechs;
 		parse_list_state_t parse_list_sts;
+		char *parse_list_cmd;
 		// Command queue
 		imap_cmd_t *pending, **pending_append;
 		imap_cmd_t *in_progress, **in_progress_append;
@@ -941,32 +942,39 @@ parse_list_init( parse_list_state_t *sts )
 }
 
 static int
-parse_list_continue( imap_store_t *ctx, char *s )
+parse_list_continue( imap_store_t *ctx )
 {
 	list_t *list;
 	int resp;
-	if ((resp = parse_imap_list( ctx, &s, &ctx->parse_list_sts )) != LIST_PARTIAL) {
+	if ((resp = parse_imap_list( ctx, &ctx->parse_list_cmd, &ctx->parse_list_sts )) != LIST_PARTIAL) {
 		list = (resp == LIST_BAD) ? NULL : ctx->parse_list_sts.head;
 		ctx->parse_list_sts.head = NULL;
-		resp = ctx->parse_list_sts.callback( ctx, list, s );
+		resp = ctx->parse_list_sts.callback( ctx, list );
 		free_list( list );
 	}
 	return resp;
 }
 
 static int
-parse_list( imap_store_t *ctx, char *s, int (*cb)( imap_store_t *ctx, list_t *list, char *s ) )
+parse_next_list( imap_store_t *ctx, int (*cb)( imap_store_t *ctx, list_t *list ) )
 {
 	parse_list_init( &ctx->parse_list_sts );
 	ctx->parse_list_sts.callback = cb;
-	return parse_list_continue( ctx, s );
+	return parse_list_continue( ctx );
 }
 
-static int parse_namespace_rsp_p2( imap_store_t *, list_t *, char * );
+static int
-static int parse_namespace_rsp_p3( imap_store_t *, list_t *, char * );
+parse_list( imap_store_t *ctx, char *s, int (*cb)( imap_store_t *ctx, list_t *list ) )
+{
+	ctx->parse_list_cmd = s;
+	return parse_next_list( ctx, cb );
+}
+
+static int parse_namespace_rsp_p2( imap_store_t *, list_t * );
+static int parse_namespace_rsp_p3( imap_store_t *, list_t * );
 
 static int
-parse_namespace_rsp( imap_store_t *ctx, list_t *list, char *s )
+parse_namespace_rsp( imap_store_t *ctx, list_t *list )
 {
 	// We use only the 1st personal namespace. Making this configurable
 	// would not add value over just specifying Path.
@@ -995,17 +1003,17 @@ parse_namespace_rsp( imap_store_t *ctx, list_t *list, char *s )
 		// Namespace response extensions may follow here; we don't care.
 	}
 
-	return parse_list( ctx, s, parse_namespace_rsp_p2 );
+	return parse_next_list( ctx, parse_namespace_rsp_p2 );
 }
 
 static int
-parse_namespace_rsp_p2( imap_store_t *ctx, list_t *list ATTR_UNUSED, char *s )
+parse_namespace_rsp_p2( imap_store_t *ctx, list_t *list ATTR_UNUSED )
 {
-	return parse_list( ctx, s, parse_namespace_rsp_p3 );
+	return parse_next_list( ctx, parse_namespace_rsp_p3 );
 }
 
 static int
-parse_namespace_rsp_p3( imap_store_t *ctx ATTR_UNUSED, list_t *list ATTR_UNUSED, char *s ATTR_UNUSED )
+parse_namespace_rsp_p3( imap_store_t *ctx ATTR_UNUSED, list_t *list ATTR_UNUSED )
 {
 	return LIST_OK;
 }
@@ -1102,7 +1110,7 @@ parse_fetched_header( char *val, uint uid, char **tuid, char **msgid, uint *msgi
 }
 
 static int
-parse_fetch_rsp( imap_store_t *ctx, list_t *list, char *s ATTR_UNUSED )
+parse_fetch_rsp( imap_store_t *ctx, list_t *list )
 {
 	list_t *body = NULL, *tmp;
 	char *tuid = NULL, *msgid = NULL, *ep;
@@ -1338,11 +1346,11 @@ parse_response_code( imap_store_t *ctx, imap_cmd_t *cmd, char *s )
 	return RESP_OK;
 }
 
-static int parse_list_rsp_p1( imap_store_t *, list_t *, char * );
+static int parse_list_rsp_p1( imap_store_t *, list_t * );
-static int parse_list_rsp_p2( imap_store_t *, list_t *, char * );
+static int parse_list_rsp_p2( imap_store_t *, list_t * );
 
 static int
-parse_list_rsp( imap_store_t *ctx, list_t *list, char *cmd )
+parse_list_rsp( imap_store_t *ctx, list_t *list )
 {
 	list_t *lp;
 
@@ -1353,11 +1361,11 @@ parse_list_rsp( imap_store_t *ctx, list_t *list, char *cmd )
 	for (lp = list->child; lp; lp = lp->next)
 		if (is_atom( lp ) && !strcasecmp( lp->val, "\\NoSelect" ))
 			return LIST_OK;
-	return parse_list( ctx, cmd, parse_list_rsp_p1 );
+	return parse_next_list( ctx, parse_list_rsp_p1 );
 }
 
 static int
-parse_list_rsp_p1( imap_store_t *ctx, list_t *list, char *cmd ATTR_UNUSED )
+parse_list_rsp_p1( imap_store_t *ctx, list_t *list )
 {
 	if (!is_opt_atom( list )) {
 		error( "IMAP error: malformed LIST response\n" );
@@ -1365,7 +1373,7 @@ parse_list_rsp_p1( imap_store_t *ctx, list_t *list, char *cmd ATTR_UNUSED )
 	}
 	if (!ctx->delimiter[0] && is_atom( list ))
 		ctx->delimiter[0] = list->val[0];
-	return parse_list( ctx, cmd, parse_list_rsp_p2 );
+	return parse_next_list( ctx, parse_list_rsp_p2 );
 }
 
 // Use this to check whether a full path refers to the actual IMAP INBOX.
@@ -1398,7 +1406,7 @@ normalize_INBOX( imap_store_t *ctx, char *arg, int argl )
 }
 
 static int
-parse_list_rsp_p2( imap_store_t *ctx, list_t *list, char *cmd ATTR_UNUSED )
+parse_list_rsp_p2( imap_store_t *ctx, list_t *list )
 {
 	string_list_t *narg;
 	char *arg, c;
@@ -1548,7 +1556,7 @@ imap_socket_read( void *aux )
 
 	for (;;) {
 		if (ctx->parse_list_sts.level) {
-			resp = parse_list_continue( ctx, NULL );
+			resp = parse_list_continue( ctx );
 		  listret:
 			if (resp == LIST_PARTIAL)
 				return;