resolvectl: break nta/domain/dns listings with newlines

We would print the whole string as a single super-long line. Let's nicely
break the text into lines that fit on the screen.

$ COLUMNS=70 build/resolvectl --no-pager nta
Global: home local intranet 23.172.in-addr.arpa lan
        18.172.in-addr.arpa 16.172.in-addr.arpa 19.172.in-addr.arpa
        25.172.in-addr.arpa 21.172.in-addr.arpa d.f.ip6.arpa
        20.172.in-addr.arpa 30.172.in-addr.arpa 17.172.in-addr.arpa
        internal 168.192.in-addr.arpa 28.172.in-addr.arpa
        22.172.in-addr.arpa 24.172.in-addr.arpa 26.172.in-addr.arpa
        corp 10.in-addr.arpa private 29.172.in-addr.arpa test
        27.172.in-addr.arpa 31.172.in-addr.arpa
Link 2 (hub0):
Link 4 (enp0s31f6):
Link 5 (wlp4s0):
Link 7 (virbr0): adsfasdfasdfasd.com 21.172.in-addr.arpa lan j b
        a.com home d.f.ip6.arpa b.com local 16.172.in-addr.arpa
        19.172.in-addr.arpa 18.172.in-addr.arpa 25.172.in-addr.arpa
        20.172.in-addr.arpa k i h 23.172.in-addr.arpa
        168.192.in-addr.arpa d g intranet 17.172.in-addr.arpa c e.com
        30.172.in-addr.arpa a f d.com e internal
Link 8 (virbr0-nic):
Link 9 (vnet0):
Link 10 (vb-rawhide):
Link 15 (wwp0s20f0u2i12):

diff --git a/src/basic/macro.h b/src/basic/macro.h
index 41c2c3289e8f2094f8648dd4767fb19c8d16b701..954bb2de2a12833998a4f83ed07678e4f57297a7 100644 (file)
--- a/src/basic/macro.h
+++ b/src/basic/macro.h
@@ -634,4 +634,6 @@ static inline int __coverity_check_and_return__(int condition) {
                 _copy;                                                  \
         })
 
+#define SIZE_ADD(x, y) ((x) >= SIZE_MAX - (y) ? SIZE_MAX : (x) + (y))
+
 #include "log.h"

diff --git a/src/resolve/resolvectl.c b/src/resolve/resolvectl.c
index 4581c2e3c8710fffdd453fb72326c63247cb7268..f199df655df1ac208c74b64a95112016c14488a1 100644 (file)
--- a/src/resolve/resolvectl.c
+++ b/src/resolve/resolvectl.c
@@ -35,6 +35,7 @@
 #include "string-table.h"
 #include "strv.h"
 #include "terminal-util.h"
+#include "utf8.h"
 #include "verbs.h"
 
 static int arg_family = AF_UNSPEC;
@@ -1302,19 +1303,39 @@ static int map_link_domains(sd_bus *bus, const char *member, sd_bus_message *m,
 }
 
 static int status_print_strv_ifindex(int ifindex, const char *ifname, char **p) {
+        const unsigned indent = strlen("Global: "); /* Use the same indentation everywhere to make things nice */
+        int pos1, pos2;
+
+        if (ifname)
+                printf("%s%nLink %i (%s)%n%s:", ansi_highlight(), &pos1, ifindex, ifname, &pos2, ansi_normal());
+        else
+                printf("%s%nGlobal%n%s:", ansi_highlight(), &pos1, &pos2, ansi_normal());
+
+        size_t cols = columns(), position = pos2 - pos1 + 2;
         char **i;
 
-        printf("%sLink %i (%s)%s:",
-               ansi_highlight(), ifindex, ifname, ansi_normal());
+        STRV_FOREACH(i, p) {
+                size_t our_len = utf8_console_width(*i); /* This returns -1 on invalid utf-8 (which shouldn't happen).
+                                                          * If that happens, we'll just print one item per line. */
 
-        STRV_FOREACH(i, p)
-                printf(" %s", *i);
+                if (position <= indent || SIZE_ADD(SIZE_ADD(position, 1), our_len) < cols) {
+                        printf(" %s", *i);
+                        position = SIZE_ADD(SIZE_ADD(position, 1), our_len);
+                } else {
+                        printf("\n%*s%s", indent, "", *i);
+                        position = SIZE_ADD(our_len, indent);
+                }
+        }
 
         printf("\n");
 
         return 0;
 }
 
+static int status_print_strv_global(char **p) {
+        return status_print_strv_ifindex(0, NULL, p);
+}
+
 struct link_info {
         uint64_t scopes_mask;
         const char *llmnr;
@@ -1636,19 +1657,6 @@ static int map_global_domains(sd_bus *bus, const char *member, sd_bus_message *m
         return 0;
 }
 
-static int status_print_strv_global(char **p) {
-        char **i;
-
-        printf("%sGlobal%s:", ansi_highlight(), ansi_normal());
-
-        STRV_FOREACH(i, p)
-                printf(" %s", *i);
-
-        printf("\n");
-
-        return 0;
-}
-
 struct global_info {
         char *current_dns;
         char *current_dns_ex;