From 4bab2b402db650122d5338c47d27e47f814f5977 Mon Sep 17 00:00:00 2001
From: Sebastian Harl <sh@tokkee.org>
Date: Mon, 12 Jan 2015 18:43:35 +0100
Subject: [PATCH] os utils: Added sdb_resolve().

This is a convenient wrapper around getaddrinfo().
---
 src/include/utils/os.h | 25 ++++++++++++++++++
 src/utils/os.c         | 59 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 84 insertions(+)

diff --git a/src/include/utils/os.h b/src/include/utils/os.h
index 38d53b2..8ffca4b 100644
--- a/src/include/utils/os.h
+++ b/src/include/utils/os.h
@@ -29,6 +29,7 @@
 #define SDB_UTILS_OS_H 1
 
 #include <sys/types.h>
+#include <netdb.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -100,6 +101,30 @@ sdb_select(int fd, int type);
 ssize_t
 sdb_write(int fd, size_t msg_len, const void *msg);
 
+enum {
+	SDB_NET_TCP = 1 << 0,
+	SDB_NET_UDP = 1 << 1,
+	SDB_NET_IP  = SDB_NET_TCP | SDB_NET_UDP,
+
+	SDB_NET_V4  = 1 << 2,
+	SDB_NET_V6  = 1 << 3,
+};
+
+/*
+ * sdb_resolve:
+ * Resolve the specified address on the specified network which may be a
+ * bitwise OR of the SDB_NET constants. The network addresses are returned in
+ * the list pointed to by 'res'. The list is allocated dynamically and has to
+ * be freed using freeaddrinfo().
+ *
+ * Returns:
+ *  - zero on success
+ *  - an error code else; use gai_strerror() to translate the error into a
+ *    human readable string
+ */
+int
+sdb_resolve(int network, const char *address, struct addrinfo **res);
+
 #ifdef __cplusplus
 } /* extern "C" */
 #endif
diff --git a/src/utils/os.c b/src/utils/os.c
index 747a370..d8f7074 100644
--- a/src/utils/os.c
+++ b/src/utils/os.c
@@ -35,6 +35,7 @@
 #include <errno.h>
 
 #include <sys/types.h>
+#include <sys/socket.h>
 #include <sys/stat.h>
 
 #include <dirent.h>
@@ -45,6 +46,7 @@
 #include <unistd.h>
 
 #include <libgen.h>
+#include <netdb.h>
 #include <pwd.h>
 
 /*
@@ -248,5 +250,62 @@ sdb_write(int fd, size_t msg_len, const void *msg)
 	return (ssize_t)msg_len;
 } /* sdb_write */
 
+int
+sdb_resolve(int network, const char *address, struct addrinfo **res)
+{
+	struct addrinfo ai_hints;
+	const char *host;
+	char *port;
+	int status;
+
+	if (! res) {
+		errno = EINVAL;
+		return EAI_SYSTEM;
+	}
+
+	if (address) {
+		host = address;
+		port = strchr(host, ':');
+		if (port) {
+			*port = '\0';
+			++port;
+		}
+		if (! *host)
+			host = NULL;
+	}
+	else {
+		host = NULL;
+		port = NULL;
+	}
+
+	memset(&ai_hints, 0, sizeof(ai_hints));
+	ai_hints.ai_flags = AI_PASSIVE | AI_ADDRCONFIG;
+	if (network & SDB_NET_V4)
+		ai_hints.ai_family = AF_INET;
+	else if (network & SDB_NET_V6)
+		ai_hints.ai_family = AF_INET6;
+	else
+		ai_hints.ai_family = AF_UNSPEC;
+	if ((network & SDB_NET_IP) == SDB_NET_IP) {
+		ai_hints.ai_socktype = 0;
+		ai_hints.ai_protocol = 0;
+	}
+	else if (network & SDB_NET_TCP) {
+		ai_hints.ai_socktype = SOCK_STREAM;
+		ai_hints.ai_protocol = IPPROTO_TCP;
+	}
+	else if (network & SDB_NET_UDP) {
+		ai_hints.ai_socktype = SOCK_DGRAM;
+		ai_hints.ai_socktype = IPPROTO_UDP;
+	}
+
+	status = getaddrinfo(host, port, &ai_hints, res);
+	if (port) {
+		--port;
+		*port = ':';
+	}
+	return status;
+} /* sdb_resolve */
+
 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 
-- 
2.30.2