From a596c41426566f54078f854e138e73a88252e7b9 Mon Sep 17 00:00:00 2001 From: Ana Rey Date: Wed, 4 Jun 2014 13:03:31 +0200 Subject: expr: log: Do not print unset values in json It changes the parse and the snprint functions to omit unset values. Also, It fixes an unnecessary comma after key-value pair type. This comma is not necessary if there is not more key-value pairs in this expr. Example: "expr":[{"type":"log"}] If It uses this rule: nft add rule ip test output log It gets this json file: [...] {"expr":[{"type":"log","prefix":"(null)","group":0,"snaplen":0,"qthreshold":0}]} [...] Now, That rule creates this json file without null values: {"expr":[{"type":"log"}]} Signed-off-by: Ana Rey Signed-off-by: Pablo Neira Ayuso --- src/expr/log.c | 56 ++++++++++++++++++++++++++++++++++---------------------- src/rule.c | 9 +++++++++ 2 files changed, 43 insertions(+), 22 deletions(-) diff --git a/src/expr/log.c b/src/expr/log.c index bd9bdc5..5032fa7 100644 --- a/src/expr/log.c +++ b/src/expr/log.c @@ -169,28 +169,20 @@ static int nft_rule_expr_log_json_parse(struct nft_rule_expr *e, json_t *root, uint16_t group, qthreshold; prefix = nft_jansson_parse_str(root, "prefix", err); - if (prefix == NULL) - return -1; - - nft_rule_expr_set_str(e, NFT_EXPR_LOG_PREFIX, prefix); + if (prefix != NULL) + nft_rule_expr_set_str(e, NFT_EXPR_LOG_PREFIX, prefix); if (nft_jansson_parse_val(root, "group", NFT_TYPE_U16, &group, - err) < 0) - return -1; - - nft_rule_expr_set_u16(e, NFT_EXPR_LOG_GROUP, group); + err) == 0) + nft_rule_expr_set_u16(e, NFT_EXPR_LOG_GROUP, group); if (nft_jansson_parse_val(root, "snaplen", NFT_TYPE_U32, &snaplen, - err) < 0) - return -1; - - nft_rule_expr_set_u32(e, NFT_EXPR_LOG_SNAPLEN, snaplen); + err) == 0) + nft_rule_expr_set_u32(e, NFT_EXPR_LOG_SNAPLEN, snaplen); if (nft_jansson_parse_val(root, "qthreshold", NFT_TYPE_U16, - &qthreshold, err) < 0) - return -1; - - nft_rule_expr_set_u16(e, NFT_EXPR_LOG_QTHRESHOLD, qthreshold); + &qthreshold, err) == 0) + nft_rule_expr_set_u16(e, NFT_EXPR_LOG_QTHRESHOLD, qthreshold); return 0; #else @@ -276,14 +268,34 @@ static int nft_rule_expr_log_snprintf_xml(char *buf, size_t size, static int nft_rule_expr_log_snprintf_json(char *buf, size_t len, struct nft_rule_expr *e) { + int ret, size = len, offset = 0; struct nft_expr_log *log = nft_expr_data(e); - return snprintf(buf, len, "\"prefix\":\"%s\"," - "\"group\":%u," - "\"snaplen\":%u," - "\"qthreshold\":%u", - log->prefix, log->group, - log->snaplen, log->qthreshold); + if (e->flags & (1 << NFT_EXPR_LOG_PREFIX)) { + ret = snprintf(buf + offset, len, "\"prefix\":\"%s\",", + log->prefix); + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + } + if (e->flags & (1 << NFT_EXPR_LOG_GROUP)) { + ret = snprintf(buf + offset, len, "\"group\":%u,", + log->group); + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + } + if (e->flags & (1 << NFT_EXPR_LOG_SNAPLEN)) { + ret = snprintf(buf + offset, len, "\"snaplen\":%u,", + log->snaplen); + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + } + if (e->flags & (1 << NFT_EXPR_LOG_QTHRESHOLD)) { + ret = snprintf(buf + offset, len, "\"qthreshold\":%u,", + log->qthreshold); + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + } + /* Remove the last comma characther */ + if (offset > 0) + offset--; + + return offset; } diff --git a/src/rule.c b/src/rule.c index ac88abb..88e9f71 100644 --- a/src/rule.c +++ b/src/rule.c @@ -816,6 +816,15 @@ static int nft_rule_snprintf_json(char *buf, size_t size, struct nft_rule *r, ret = expr->ops->snprintf(buf+offset, len, type, flags, expr); SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + /* + * Remove comma from the first element if there is type + * key-value pair only. Example: "expr":[{"type":"log"}] + */ + if (ret == 0) { + offset--; + len--; + } + ret = snprintf(buf+offset, len, "},"); SNPRINTF_BUFFER_SIZE(ret, size, len, offset); -- cgit v1.2.3