src: new error reporting approach for XML/JSON parsers

I have added a new structure for reporting some errors in parser
that we can't cover with errno.

In this patch, we have three errors that we can't cover with errno:

NFT_PARSE_EBADINPUT : Bad XML/JSON format in the input
NFT_PARSE_EMISSINGNODE : Missing node in our input
NFT_PARSE_EBADTYPE : Wrong type value in a node

Signed-off-by: Alvaro Neira Ayuso <alvaroneay@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

6 files changed, 23 insertions, 6 deletions

diff --git a/include/libnftables/chain.h b/include/libnftables/chain.h
index 8b4eab9..dec1a77 100644
--- a/include/libnftables/chain.h
+++ b/include/libnftables/chain.h
@@ -51,7 +51,8 @@ struct nlmsghdr;
 
 void nft_chain_nlmsg_build_payload(struct nlmsghdr *nlh, const struct nft_chain *t);
 
-int nft_chain_parse(struct nft_chain *c, enum nft_parse_type type, const char *data);
+int nft_chain_parse(struct nft_chain *c, enum nft_parse_type type,
+		    const char *data, struct nft_parse_err *err);
 int nft_chain_snprintf(char *buf, size_t size, struct nft_chain *t, uint32_t type, uint32_t flags);
 int nft_chain_fprintf(FILE *fp, struct nft_chain *c, uint32_t type, uint32_t flags);
 
diff --git a/include/libnftables/common.h b/include/libnftables/common.h
index 9cd92b2..1ef88ba 100644
--- a/include/libnftables/common.h
+++ b/include/libnftables/common.h
@@ -1,6 +1,12 @@
 #ifndef _LIBNFTABLES_COMMON_H_
 #define _LIBNFTABLES_COMMON_H_
 
+enum {
+	NFT_PARSE_EBADINPUT	= 0,
+	NFT_PARSE_EMISSINGNODE,
+	NFT_PARSE_EBADTYPE,
+};
+
 enum nft_output_type {
 	NFT_OUTPUT_DEFAULT	= 0,
 	NFT_OUTPUT_XML,
@@ -14,7 +20,12 @@ enum nft_parse_type {
 	NFT_PARSE_MAX,
 };
 
+struct nft_parse_err;
+
 struct nlmsghdr *nft_nlmsg_build_hdr(char *buf, uint16_t cmd, uint16_t family,
 				     uint16_t type, uint32_t seq);
 
+struct nft_parse_err *nft_parse_err_alloc(void);
+void nft_parse_err_free(struct nft_parse_err *);
+int nft_parse_perror(const char *str, struct nft_parse_err *err);
 #endif
diff --git a/include/libnftables/rule.h b/include/libnftables/rule.h
index 86dbc17..1510203 100644
--- a/include/libnftables/rule.h
+++ b/include/libnftables/rule.h
@@ -47,7 +47,8 @@ struct nlmsghdr;
 
 void nft_rule_nlmsg_build_payload(struct nlmsghdr *nlh, struct nft_rule *t);
 
-int nft_rule_parse(struct nft_rule *r, enum nft_parse_type type, const char *data);
+int nft_rule_parse(struct nft_rule *r, enum nft_parse_type type,
+		   const char *data, struct nft_parse_err *err);
 int nft_rule_snprintf(char *buf, size_t size, struct nft_rule *t, uint32_t type, uint32_t flags);
 int nft_rule_fprintf(FILE *fp, struct nft_rule *r, uint32_t type, uint32_t flags);
 
diff --git a/include/libnftables/ruleset.h b/include/libnftables/ruleset.h
index 1ec3059..b523346 100644
--- a/include/libnftables/ruleset.h
+++ b/include/libnftables/ruleset.h
@@ -30,7 +30,8 @@ void nft_ruleset_attr_unset(struct nft_ruleset *r, uint16_t attr);
 void nft_ruleset_attr_set(struct nft_ruleset *r, uint16_t attr, void *data);
 const void *nft_ruleset_attr_get(const struct nft_ruleset *r, uint16_t attr);
 
-int nft_ruleset_parse(struct nft_ruleset *rs, enum nft_parse_type type, const char *data);
+int nft_ruleset_parse(struct nft_ruleset *rs, enum nft_parse_type type,
+		      const char *data, struct nft_parse_err *err);
 int nft_ruleset_snprintf(char *buf, size_t size, const struct nft_ruleset *rs, uint32_t type, uint32_t flags);
 int nft_ruleset_fprintf(FILE *fp, const struct nft_ruleset *rs, uint32_t type, uint32_t flags);
 
diff --git a/include/libnftables/set.h b/include/libnftables/set.h
index 13ac857..9711729 100644
--- a/include/libnftables/set.h
+++ b/include/libnftables/set.h
@@ -60,7 +60,8 @@ struct nft_set *nft_set_list_iter_cur(struct nft_set_list_iter *iter);
 struct nft_set *nft_set_list_iter_next(struct nft_set_list_iter *iter);
 void nft_set_list_iter_destroy(struct nft_set_list_iter *iter);
 
-int nft_set_parse(struct nft_set *s, enum nft_parse_type type, const char *data);
+int nft_set_parse(struct nft_set *s, enum nft_parse_type type,
+		  const char *data, struct nft_parse_err *err);
 
 /*
  * Set elements
@@ -98,7 +99,8 @@ void nft_set_elem_nlmsg_build_payload(struct nlmsghdr *nlh, struct nft_set_elem
 
 int nft_set_elem_nlmsg_parse(const struct nlmsghdr *nlh, struct nft_set_elem *s);
 
-int nft_set_elem_parse(struct nft_set_elem *e, enum nft_parse_type type, const char *data);
+int nft_set_elem_parse(struct nft_set_elem *e, enum nft_parse_type type,
+		       const char *data, struct nft_parse_err *err);
 int nft_set_elem_snprintf(char *buf, size_t size, struct nft_set_elem *s, uint32_t type, uint32_t flags);
 int nft_set_elem_fprintf(FILE *fp, struct nft_set_elem *se, uint32_t type, uint32_t flags);
 
diff --git a/include/libnftables/table.h b/include/libnftables/table.h
index be60da9..80f2349 100644
--- a/include/libnftables/table.h
+++ b/include/libnftables/table.h
@@ -39,7 +39,8 @@ struct nlmsghdr;
 
 void nft_table_nlmsg_build_payload(struct nlmsghdr *nlh, const struct nft_table *t);
 
-int nft_table_parse(struct nft_table *t, enum nft_parse_type type, const char *data);
+int nft_table_parse(struct nft_table *t, enum nft_parse_type type,
+		    const char *data, struct nft_parse_err *err);
 int nft_table_snprintf(char *buf, size_t size, struct nft_table *t, uint32_t type, uint32_t flags);
 int nft_table_fprintf(FILE *fp, struct nft_table *t, uint32_t type, uint32_t flags);