Add LD_BTRACK log domain for bootstrap tracker

Part of ticket 27167.

doc/tor.1.txt

@@ -678,7 +678,7 @@ GENERAL OPTIONS
     The currently recognized domains are: general, crypto, net, config, fs,
     protocol, mm, http, app, control, circ, rend, bug, dir, dirserv, or, edge,
     acct, hist, handshake, heartbeat, channel, sched, guard, consdiff, dos,
-    process, and pt.
+    process, pt, and btrack.
     Domain names are case-insensitive. +
  +
     For example, "`Log [handshake]debug [~net,~mm]info notice stdout`" sends

src/lib/log/log.c

@@ -1268,7 +1268,7 @@ static const char *domain_list[] = {
   "GENERAL", "CRYPTO", "NET", "CONFIG", "FS", "PROTOCOL", "MM",
   "HTTP", "APP", "CONTROL", "CIRC", "REND", "BUG", "DIR", "DIRSERV",
   "OR", "EDGE", "ACCT", "HIST", "HANDSHAKE", "HEARTBEAT", "CHANNEL",
-  "SCHED", "GUARD", "CONSDIFF", "DOS", "PROCESS", "PT", NULL
+  "SCHED", "GUARD", "CONSDIFF", "DOS", "PROCESS", "PT", "BTRACK", NULL
 };
 
 /** Return a bitmask for the log domain for which <b>domain</b> is the name,

src/lib/log/log.h

@@ -111,8 +111,10 @@
 #define LD_PROCESS   (1u<<26)
 /** Pluggable Transports. */
 #define LD_PT        (1u<<27)
+/** Bootstrap tracker. */
+#define LD_BTRACK    (1u<<28)
 /** Number of logging domains in the code. */
-#define N_LOGGING_DOMAINS 28
+#define N_LOGGING_DOMAINS 29
 
 /** This log message is not safe to send to a callback-based logger
  * immediately.  Used as a flag, not a log domain. */