[PATCH nft 0/2] follow up work on the libedit support

[PATCH nft 0/2] follow up work on the libedit support

[Pablo Neira Ayuso]

Hi,

This is a follow up to address a few issues with libedit readline
support: tests/shell now works fine.

Pablo Neira Ayuso (2):
  cli: use plain readline() interface
  main: fix typo in cli definition

 src/cli.c  | 21 +++++++++++----------
 src/main.c |  2 +-
 2 files changed, 12 insertions(+), 11 deletions(-)

-- 
2.20.1

[PATCH nft 1/2] cli: use plain readline() interface

[Pablo Neira Ayuso]

Instead of the alternate interface [1].

I spent a bit of time debugging an issue with libedit support
9420423900a2 ("cli: add libedit support") that broke tests/shell.

This is the reproducer:

 # nft -i << EOF
 list ruleset
 EOF

which makes rl_callback_read_char() loop forever on read() as shown by
strace. The rl_line_buffer variable does not accumulate the typed
characters as it should when redirecting the standard input for some
reason.

Given our interactive interface is fairly simple at this stage, switch
to use the readline() interface instead of rl_callback_read_char().

[1] https://docs.freebsd.org/info/readline/readline.info.Alternate_Interface.html

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 src/cli.c | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/src/cli.c b/src/cli.c
index 45811595fc77..f46971b848e5 100644
--- a/src/cli.c
+++ b/src/cli.c
@@ -154,28 +154,29 @@ static void cli_complete(char *line)
 	free(line);
 }
 
-static char **cli_completion(const char *text, int start, int end)
-{
-	return NULL;
-}
-
 int cli_init(struct nft_ctx *nft)
 {
+	char *line;
+
 	cli_nft = nft;
 	rl_readline_name = (char *)"nft";
 	rl_instream  = stdin;
 	rl_outstream = stdout;
 
-	rl_callback_handler_install(CMDLINE_PROMPT, cli_complete);
-	rl_attempted_completion_function = cli_completion;
-
 	init_histfile();
 
 	read_history(histfile);
 	history_set_pos(history_length);
 
-	while (true)
-		rl_callback_read_char();
+	rl_set_prompt(CMDLINE_PROMPT);
+	while ((line = readline(rl_prompt)) != NULL) {
+		line = cli_append_multiline(line);
+		if (!line)
+			continue;
+
+		cli_complete(line);
+	}
+
 	return 0;
 }
 
-- 
2.20.1

[PATCH nft 2/2] main: fix typo in cli definition

[Pablo Neira Ayuso]

9420423900a2 ("cli: add libedit support") updated HAVE_LIBREADLINE to
HAVE_READLINE by mistake.

Fixes: 9420423900a2 ("cli: add libedit support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 src/main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/main.c b/src/main.c
index 0a1c47758d1a..80cf1acf0f7f 100644
--- a/src/main.c
+++ b/src/main.c
@@ -227,7 +227,7 @@ static void show_version(void)
 {
 	const char *cli, *minigmp, *json, *xt;
 
-#if defined(HAVE_READLINE)
+#if defined(HAVE_LIBREADLINE)
 	cli = "readline";
 #elif defined(HAVE_LIBEDIT)
 	cli = "editline";
-- 
2.20.1