From: Yu Watanabe <watanabe.yu+github@gmail.com>
Date: Wed, 9 Jun 2021 14:27:20 +0000 (+0900)
Subject: sd-device: introduce sd_device_new_from_ifname/ifindex()
X-Git-Tag: v249-rc1~28^2~5
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=bd44a727f736d21dd47b5dfbdbe79d21acbdc2a4;p=thirdparty%2Fsystemd.git

sd-device: introduce sd_device_new_from_ifname/ifindex()
---

diff --git a/src/libsystemd/libsystemd.sym b/src/libsystemd/libsystemd.sym
index 1606981e1e1..3730db6eef9 100644
--- a/src/libsystemd/libsystemd.sym
+++ b/src/libsystemd/libsystemd.sym
@@ -759,4 +759,6 @@ global:
         sd_device_get_usec_initialized;
         sd_device_trigger_with_uuid;
         sd_device_get_trigger_uuid;
+        sd_device_new_from_ifname;
+        sd_device_new_from_ifindex;
 } LIBSYSTEMD_248;
diff --git a/src/libsystemd/sd-device/sd-device.c b/src/libsystemd/sd-device/sd-device.c
index f31416da530..b5e7a1a44d1 100644
--- a/src/libsystemd/sd-device/sd-device.c
+++ b/src/libsystemd/sd-device/sd-device.c
@@ -14,10 +14,12 @@
 #include "dirent-util.h"
 #include "fd-util.h"
 #include "fileio.h"
+#include "format-util.h"
 #include "fs-util.h"
 #include "hashmap.h"
 #include "id128-util.h"
 #include "macro.h"
+#include "netlink-util.h"
 #include "parse-util.h"
 #include "path-util.h"
 #include "set.h"
@@ -245,6 +247,52 @@ _public_ int sd_device_new_from_devnum(sd_device **ret, char type, dev_t devnum)
         return sd_device_new_from_syspath(ret, syspath);
 }
 
+static int device_new_from_main_ifname(sd_device **ret, const char *ifname) {
+        const char *syspath;
+
+        assert(ret);
+        assert(ifname);
+
+        syspath = strjoina("/sys/class/net/", ifname);
+        return sd_device_new_from_syspath(ret, syspath);
+}
+
+_public_ int sd_device_new_from_ifname(sd_device **ret, const char *ifname) {
+        _cleanup_free_ char *main_name = NULL;
+        int r;
+
+        assert_return(ret, -EINVAL);
+        assert_return(ifname, -EINVAL);
+
+        r = parse_ifindex(ifname);
+        if (r > 0)
+                return sd_device_new_from_ifindex(ret, r);
+
+        if (ifname_valid(ifname)) {
+                r = device_new_from_main_ifname(ret, ifname);
+                if (r >= 0)
+                        return r;
+        }
+
+        r = rtnl_resolve_link_alternative_name(NULL, ifname, &main_name);
+        if (r < 0)
+                return r;
+
+        return device_new_from_main_ifname(ret, main_name);
+}
+
+_public_ int sd_device_new_from_ifindex(sd_device **ret, int ifindex) {
+        char ifname[IF_NAMESIZE + 1];
+
+        assert_return(ret, -EINVAL);
+        assert_return(ifindex > 0, -EINVAL);
+
+        if (!format_ifname(ifindex, ifname))
+                return -ENODEV;
+
+        return device_new_from_main_ifname(ret, ifname);
+}
+
 static int device_strjoin_new(
                 const char *a,
                 const char *b,
@@ -643,37 +691,13 @@ _public_ int sd_device_new_from_device_id(sd_device **ret, const char *id) {
         }
 
         case 'n': {
-                _cleanup_(sd_device_unrefp) sd_device *device = NULL;
-                _cleanup_close_ int sk = -1;
-                struct ifreq ifr = {};
                 int ifindex;
 
-                r = ifr.ifr_ifindex = parse_ifindex(id + 1);
-                if (r < 0)
-                        return r;
+                ifindex = parse_ifindex(id + 1);
+                if (ifindex < 0)
+                        return ifindex;
 
-                sk = socket_ioctl_fd();
-                if (sk < 0)
-                        return sk;
-
-                r = ioctl(sk, SIOCGIFNAME, &ifr);
-                if (r < 0)
-                        return -errno;
-
-                r = sd_device_new_from_subsystem_sysname(&device, "net", ifr.ifr_name);
-                if (r < 0)
-                        return r;
-
-                r = sd_device_get_ifindex(device, &ifindex);
-                if (r < 0)
-                        return r;
-
-                /* this is racey, so we might end up with the wrong device */
-                if (ifr.ifr_ifindex != ifindex)
-                        return -ENODEV;
-
-                *ret = TAKE_PTR(device);
-                return 0;
+                return sd_device_new_from_ifindex(ret, ifindex);
         }
 
         case '+': {
diff --git a/src/systemd/sd-device.h b/src/systemd/sd-device.h
index 04599ea3821..7ab0a8334eb 100644
--- a/src/systemd/sd-device.h
+++ b/src/systemd/sd-device.h
@@ -62,6 +62,8 @@ int sd_device_new_from_devnum(sd_device **ret, char type, dev_t devnum);
 int sd_device_new_from_subsystem_sysname(sd_device **ret, const char *subsystem, const char *sysname);
 int sd_device_new_from_device_id(sd_device **ret, const char *id);
 int sd_device_new_from_stat_rdev(sd_device **ret, const struct stat *st);
+int sd_device_new_from_ifname(sd_device **ret, const char *ifname);
+int sd_device_new_from_ifindex(sd_device **ret, int ifindex);
 
 int sd_device_get_parent(sd_device *child, sd_device **ret);
 int sd_device_get_parent_with_subsystem_devtype(sd_device *child, const char *subsystem, const char *devtype, sd_device **ret);