ALT: Add helper to fix llama --help suitable for help2man

Signed-off-by: Vitaly Chikunov <vt@altlinux.org>

.gear/gen-manpage

@@ -0,0 +1,60 @@
+#!/bin/bash -e
+
+#
+# Wrapper around llama-cli to massage the output to be more palatable to
+# help2man for generating a manual page.
+#
+# Invoke as:
+#   gen-manpage build/bin/llama-cli --name='LLM inference in C/C++'
+#
+# This script is in the public domain and may be distributed or modified
+# without restriction.
+#
+
+: ${HELP2MAN:=help2man}
+
+tmp=$(mktemp -d)
+trap "rm -rf $tmp" EXIT HUP INT
+
+cmd="${1?}"
+shift
+
+# --version goes to stderr?
+$cmd --version 2>$tmp/version
+
+# --help to stdout, some diagnostics to stderr
+$cmd --help    >$tmp/help 2>/dev/null
+
+# Ensure we got something from both.
+test -s $tmp/version && test -s $tmp/help
+
+cmd="${cmd##*/}"
+
+# Strip out just version.
+sed -i -n "s/^version: /$cmd /p" $tmp/version
+
+# Convert ---thing--- to subheadings, and clean up args.
+sed -i \
+    -e 's/^----- \([A-Za-z].*\) -----/\1:/' \
+    -e 's/^[a-z].*:$/\u&/' \
+    -e '/^[A-Za-z].*:$/s/ [a-z]/\U&/g' \
+    -e 's/^-\(-\?[a-zA-Z0-9][^ ]*,\)\( *\)\(-.*\)  /-\1 \3\2 /' \
+    -e 's/^-\(.*\)   / -\1  /' \
+    -e '/  *[^ ].*: [^ ]/s/:/:  /' \
+    $tmp/help
+
+cat <<EOT >$tmp/${cmd##*/}
+#!/bin/bash
+
+for arg; do
+  case "\$arg" in
+  --version) cat $tmp/version;;
+  --help)    cat $tmp/help;;
+  esac
+done
+EOT
+
+chmod a+x "$tmp/$cmd"
+${HELP2MAN} --no-info "$@" "$tmp/$cmd"
+
+exit $?