journal: in json and export mode use double underscores to prefix location fields

Many programming languages don't allow variable names beginning in dots,
hence let's use double underscores for the location fields instead. This
gets us the simple rule:

__ is the prefix for location fields (i.e. fields that are used to
identify entries, rather than part of the entries)

_ is the prefix for trusted fields (i.e. those fields journald itself
adds to all entries)

no prefix for unrusted fields (i.e. all fields normal client code sends
us)

diff --git a/src/logs-show.c b/src/logs-show.c
index f71c6b08455d8823d29b8fd10b064a8b23bf4d58..0a07a77bed469bec2a4bae569a441d725b009b3c 100644 (file)
--- a/src/logs-show.c
+++ b/src/logs-show.c
@@ -347,10 +347,10 @@ static int output_export(sd_journal *j, unsigned line, unsigned n_columns, bool
                 return r;
         }
 
-        printf(".cursor=%s\n"
-               ".realtime=%llu\n"
-               ".monotonic=%llu\n"
-               ".boot_id=%s\n",
+        printf("__CURSOR=%s\n"
+               "__REALTIME=%llu\n"
+               "__MONOTONIC=%llu\n"
+               "__BOOT_ID=%s\n",
                cursor,
                (unsigned long long) realtime,
                (unsigned long long) monotonic,
@@ -459,10 +459,10 @@ static int output_json(sd_journal *j, unsigned line, unsigned n_columns, bool sh
                 fputs(",\n", stdout);
 
         printf("{\n"
-               "\t\".cursor\" : \"%s\",\n"
-               "\t\".realtime\" : %llu,\n"
-               "\t\".monotonic\" : %llu,\n"
-               "\t\".boot_id\" : \"%s\"",
+               "\t\"__CURSOR\" : \"%s\",\n"
+               "\t\"__REALTIME\" : \"%llu\",\n"
+               "\t\"__MONOTONIC\" : \"%llu\",\n"
+               "\t\"__BOOT_ID\" : \"%s\"",
                cursor,
                (unsigned long long) realtime,
                (unsigned long long) monotonic,