format-util: introduce format_ifname_full()

2 files changed, 24 insertions, 3 deletions

diff --git a/src/basic/format-util.c b/src/basic/format-util.c
index aec929a06a..9fea2e0690 100644
--- a/src/basic/format-util.c
+++ b/src/basic/format-util.c
@@ -4,11 +4,24 @@
 
 #include "format-util.h"
 #include "memory-util.h"
+#include "stdio-util.h"
 
-char *format_ifname(int ifindex, char buf[static IF_NAMESIZE + 1]) {
+assert_cc(DECIMAL_STR_MAX(int) + 1 <= IF_NAMESIZE + 1);
+char *format_ifname_full(int ifindex, char buf[static IF_NAMESIZE + 1], FormatIfnameFlag flag) {
         /* Buffer is always cleared */
         memzero(buf, IF_NAMESIZE + 1);
-        return if_indextoname(ifindex, buf);
+        if (if_indextoname(ifindex, buf))
+                return buf;
+
+        if (!FLAGS_SET(flag, FORMAT_IFNAME_IFINDEX))
+                return NULL;
+
+        if (FLAGS_SET(flag, FORMAT_IFNAME_IFINDEX_WITH_PERCENT))
+                snprintf(buf, IF_NAMESIZE + 1, "%%%d", ifindex);
+        else
+                snprintf(buf, IF_NAMESIZE + 1, "%d", ifindex);
+
+        return buf;
 }
 
 char *format_bytes_full(char *buf, size_t l, uint64_t t, FormatBytesFlag flag) {
diff --git a/src/basic/format-util.h b/src/basic/format-util.h
index e0d184a541..59622508a3 100644
--- a/src/basic/format-util.h
+++ b/src/basic/format-util.h
@@ -68,7 +68,15 @@
 #  error Unknown ino_t size
 #endif
 
-char *format_ifname(int ifindex, char buf[static IF_NAMESIZE + 1]);
+typedef enum {
+        FORMAT_IFNAME_IFINDEX              = 1 << 0,
+        FORMAT_IFNAME_IFINDEX_WITH_PERCENT = (1 << 1) | FORMAT_IFNAME_IFINDEX,
+} FormatIfnameFlag;
+
+char *format_ifname_full(int ifindex, char buf[static IF_NAMESIZE + 1], FormatIfnameFlag flag);
+static inline char *format_ifname(int ifindex, char buf[static IF_NAMESIZE + 1]) {
+        return format_ifname_full(ifindex, buf, 0);
+}
 
 typedef enum {
         FORMAT_BYTES_USE_IEC     = 1 << 0,