From d583ae698d8cee05a02f75383877566535ca6cad Mon Sep 17 00:00:00 2001
From: Jacob Nevins <jacobn@chiark.greenend.org.uk>
Date: Sun, 16 Jul 2023 16:01:02 +0100
Subject: [PATCH 1/3] docs: Tiny improvements to log file name docs.

Note that &H type substitutions are case-insensitive, and fix a typo.
---
 doc/config.but | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/doc/config.but b/doc/config.but
index 488c157e..96f73396 100644
--- a/doc/config.but
+++ b/doc/config.but
@@ -219,7 +219,9 @@ digits.
 \b \c{&P} will be replaced by the port number you are connecting to on
 the target host.
 
-For example, if you enter the host name
+(These are all case-insensitive.)
+
+For example, if you enter the file name
 \c{c:\\puttylogs\\log-&h-&y&m&d-&t.dat}, you will end up with files looking
 like
 

From 209cf8013bc71ed739054f013062b44feea157d8 Mon Sep 17 00:00:00 2001
From: Jacob Nevins <jacobn@chiark.greenend.org.uk>
Date: Sun, 16 Jul 2023 16:00:29 +0100
Subject: [PATCH 2/3] Add missing consts around xlatlognam().

---
 logging.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/logging.c b/logging.c
index e065f1a4..ff687cb7 100644
--- a/logging.c
+++ b/logging.c
@@ -22,8 +22,9 @@ struct LogContext {
     int logtype;                       /* cached out of conf */
 };
 
-static Filename *xlatlognam(Filename *s, char *hostname, int port,
-                            struct tm *tm);
+static Filename *xlatlognam(const Filename *s,
+                            const char *hostname, int port,
+                            const struct tm *tm);
 
 /*
  * Internal wrapper function which must be called for _all_ output
@@ -451,10 +452,12 @@ void log_reconfig(LogContext *ctx, Conf *conf)
  *
  * "&Y":YYYY   "&m":MM   "&d":DD   "&T":hhmmss   "&h":<hostname>   "&&":&
  */
-static Filename *xlatlognam(Filename *src, char *hostname, int port,
-                            struct tm *tm)
+static Filename *xlatlognam(const Filename *src,
+                            const char *hostname, int port,
+                            const struct tm *tm)
 {
-    char buf[32], *bufp;
+    char buf[32];
+    const char *bufp;
     int size;
     strbuf *buffer;
     const char *s;

From c406d8efe539b165cd3386a6bf1ae3e5ee6ebc83 Mon Sep 17 00:00:00 2001
From: Jacob Nevins <jacobn@chiark.greenend.org.uk>
Date: Sun, 16 Jul 2023 16:03:24 +0100
Subject: [PATCH 3/3] logging: allow &H to expand to serial line.

For serial connections, &H generally expanded to the empty string.
This seems more useful.
(It so happens that &H _could_ expand to the serial line if it came from
the command-line, but that's accidental.)
---
 doc/config.but | 3 ++-
 logging.c      | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/doc/config.but b/doc/config.but
index 96f73396..1990a92a 100644
--- a/doc/config.but
+++ b/doc/config.but
@@ -214,7 +214,8 @@ digits.
 \b \c{&T} will be replaced by the current time, as six digits
 (HHMMSS) with no punctuation.
 
-\b \c{&H} will be replaced by the host name you are connecting to.
+\b \c{&H} will be replaced by the host name you are connecting to
+(or the serial line, for a serial connection).
 
 \b \c{&P} will be replaced by the port number you are connecting to on
 the target host.
diff --git a/logging.c b/logging.c
index ff687cb7..031aae4a 100644
--- a/logging.c
+++ b/logging.c
@@ -174,7 +174,7 @@ void logfopen(LogContext *ctx)
         filename_free(ctx->currlogfilename);
     ctx->currlogfilename =
         xlatlognam(conf_get_filename(ctx->conf, CONF_logfilename),
-                   conf_get_str(ctx->conf, CONF_host),
+                   conf_dest(ctx->conf),    /* hostname or serial line */
                    conf_get_int(ctx->conf, CONF_port), &tm);
 
     if (open_for_write_would_lose_data(ctx->currlogfilename)) {