Minimally resurrect doxygen documentation

The documentation was written in the days before doxygen required groups or even
doxygen.cfg, so create doxygen.cfg.in and introduce one \defgroup per source
file, encompassing pretty-much the whole file.

Also add a tiny \mainpage.

Added:

 doxygen.cfg.in: Same as for libmnl except FILE_PATTERNS = *.c libnfnetlink.h

Updated:

 configure.ac: Create doxygen.cfg

 src/iftable.c: Add defgroup

 src/libnfnetlink.c: Add mainpage and defgroup

Signed-off-by: Duncan Roe <duncan_roe@optusnet.com.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

2 files changed, 25 insertions, 1 deletions

diff --git a/src/iftable.c b/src/iftable.c
index 157f97b..6d1d135 100644
--- a/src/iftable.c
+++ b/src/iftable.c
@@ -24,6 +24,11 @@
 #include "rtnl.h"
 #include "linux_list.h"
 
+/**
+ * \defgroup iftable Functions in iftable.c
+ * @{
+ */
+
 struct ifindex_node {
 	struct list_head head;
 
@@ -333,3 +338,7 @@ int nlif_fd(struct nlif_handle *h)
 
 	return -1;
 }
+
+/**
+ * @}
+ */
diff --git a/src/libnfnetlink.c b/src/libnfnetlink.c
index df57533..3db21e0 100644
--- a/src/libnfnetlink.c
+++ b/src/libnfnetlink.c
@@ -52,6 +52,18 @@
 
 #include <libnfnetlink/libnfnetlink.h>
 
+/**
+ * \mainpage
+ *
+ * libnfnetlink is the bottom-level communication between the kernel and
+ * userspace
+ */
+
+/**
+ * \defgroup libnfnetlink Functions in libnfnetlink.c
+ * @{
+ */
+
 #ifndef NETLINK_ADD_MEMBERSHIP
 #define NETLINK_ADD_MEMBERSHIP 1
 #endif
@@ -60,7 +72,6 @@
 #define SOL_NETLINK 270
 #endif
 
-
 #define nfnl_error(format, args...) \
 	fprintf(stderr, "%s: " format "\n", __FUNCTION__, ## args)
 
@@ -1572,3 +1583,7 @@ int nfnl_query(struct nfnl_handle *h, struct nlmsghdr *nlh)
 
 	return nfnl_catch(h);
 }
+
+/**
+ * @}
+ */