journal-file, journalctl: provide better hint about unsupported features

https://bugzilla.redhat.com/show_bug.cgi?id=1416201

$ journalctl -b
Journal file /var/log/journal/ad18f69b80264b52bb3b766240742383/system@0005467d92e23784-a6571c8b69d09124.journal~ uses an unsupported feature, ignoring file.
Use SYSTEMD_LOG_LEVEL=debug journalctl --file=/var/log/journal/ad18f69b80264b52bb3b766240742383/system@0005467d92e23784-a6571c8b69d09124.journal~ to see the details.
-- No entries --

$ journalctl --file=/var/log/journal/ad18f69b80264b52bb3b766240742383/system@0005467d92e23784-a6571c8b69d09124.journal~
Journal file /var/log/journal/ad18f69b80264b52bb3b766240742383/system@0005467d92e23784-a6571c8b69d09124.journal~ uses incompatible flag lz4-compressed disabled at compilation time.
Failed to open journal file /var/log/journal/ad18f69b80264b52bb3b766240742383/system@0005467d92e23784-a6571c8b69d09124.journal~: Protocol not supported
mmap cache statistics: 0 hit, 1 miss
Failed to open files: Protocol not supported

diff --git a/src/journal/journal-file.c b/src/journal/journal-file.c
index d67b597..7fcb30a 100644 (file)
--- a/src/journal/journal-file.c
+++ b/src/journal/journal-file.c
@@ -42,6 +42,7 @@
 #include "sd-event.h"
 #include "set.h"
 #include "string-util.h"
+#include "strv.h"
 #include "xattr-util.h"
 
 #define DEFAULT_DATA_HASH_TABLE_SIZE (2047ULL*sizeof(HashItem))
@@ -517,12 +518,27 @@ static bool warn_wrong_flags(const JournalFile *f, bool compatible) {
 
         if (flags & ~supported) {
                 if (flags & ~any)
-                        log_debug("Journal file %s has unknown %s flags %"PRIx32,
+                        log_debug("Journal file %s has unknown %s flags 0x%"PRIx32,
                                   f->path, type, flags & ~any);
                 flags = (flags & any) & ~supported;
-                if (flags)
-                        log_debug("Journal file %s uses %s flags %"PRIx32" disabled at compilation time.",
-                                  f->path, type, flags);
+                if (flags) {
+                        const char* strv[3];
+                        unsigned n = 0;
+                        _cleanup_free_ char *t = NULL;
+
+                        if (compatible && (flags & HEADER_COMPATIBLE_SEALED))
+                                strv[n++] = "sealed";
+                        if (!compatible && (flags & HEADER_INCOMPATIBLE_COMPRESSED_XZ))
+                                strv[n++] = "xz-compressed";
+                        if (!compatible && (flags & HEADER_INCOMPATIBLE_COMPRESSED_LZ4))
+                                strv[n++] = "lz4-compressed";
+                        strv[n] = NULL;
+                        assert(n < ELEMENTSOF(strv));
+
+                        t = strv_join((char**) strv, ", ");
+                        log_debug("Journal file %s uses %s %s %s disabled at compilation time.",
+                                  f->path, type, n > 1 ? "flags" : "flag", strnull(t));
+                }
                 return true;
         }
 

diff --git a/src/journal/journalctl.c b/src/journal/journalctl.c
index 2a5f2b3..2639fd6 100644 (file)
--- a/src/journal/journalctl.c
+++ b/src/journal/journalctl.c
@@ -1910,7 +1910,9 @@ static int access_check(sd_journal *j) {
                         break;
 
                 case EPROTONOSUPPORT:
-                        log_warning_errno(err, "Journal file %s uses an unsupported feature, ignoring file.", path);
+                        log_warning_errno(err, "Journal file %1$s uses an unsupported feature, ignoring file.\n"
+                                               "Use SYSTEMD_LOG_LEVEL=debug journalctl --file=%1$s to see the details.",
+                                               path);
                         break;
 
                 case EBADMSG: