src: error reporting with -f and read from stdin

Reading from stdin requires to store the ruleset in a buffer so error
reporting works accordingly, eg.

 # cat ruleset.nft | nft -f -
 /dev/stdin:3:13-13: Error: unknown identifier 'x'
                 ip saddr $x
                           ^

The error reporting infrastructure performs a fseek() on the file
descriptor which does not work in this case since the data from the
descriptor has been already consumed.

This patch adds a new stdin input descriptor to perform this special
handling which consists on re-routing this request through the buffer
functions.

Fixes: 935f82e7dd49 ("Support 'nft -f -' to read from stdin")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/src/scanner.l b/src/scanner.l
index f28bf315..7dcc45c2 100644
--- a/src/scanner.l
+++ b/src/scanner.l
@@ -1032,7 +1032,7 @@ void scanner_push_buffer(void *scanner, const struct input_descriptor *indesc,
 	new_indesc = xzalloc(sizeof(struct input_descriptor));
 	memcpy(new_indesc, indesc, sizeof(*new_indesc));
 	new_indesc->data = buffer;
-	new_indesc->name = NULL;
+	new_indesc->name = xstrdup(indesc->name);
 	scanner_push_indesc(state, new_indesc);
 
 	b = yy_scan_string(buffer, scanner);