From 761af595e18e8364282ea752142b19ada569ac8e Mon Sep 17 00:00:00 2001
From: Giuseppe Bilotta <giuseppe.bilotta@gmail.com>
Date: Tue, 18 Nov 2008 01:00:14 +0100
Subject: [PATCH] Try to guess the user's name and email

A common use case for RCS fast export is likely to be of a user trying to
convert its RCS histories into git histories. In these cases we don't need an
authors file, since the committer full name and email are information likely
to be found elsewhere.

We look at the git config, but also the gecos entry in the passwd file. As
extreme resources we also peek in their .hgrc and .vimrc files
---
 rcs-fast-export.rb | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/rcs-fast-export.rb b/rcs-fast-export.rb
index a6d010c..7d6f649 100755
--- a/rcs-fast-export.rb
+++ b/rcs-fast-export.rb
@@ -424,6 +424,52 @@ opts.each do |opt, arg|
 	end
 end
 
+require 'etc'
+
+user = Etc.getlogin || ENV['USER']
+
+# steal username/email data from other init files that may contain the
+# information
+def steal_username
+	[
+		# the user's .hgrc file for a username field
+		['~/.hgrc',   /^\s*username\s*=\s*(["'])?(.*)\1$/,       2],
+		# the user's .(g)vimrc for a changelog_username setting
+		['~/.vimrc',  /changelog_username\s*=\s*(["'])?(.*)\1$/, 2],
+		['~/.gvimrc', /changelog_username\s*=\s*(["'])?(.*)\1$/, 2],
+		[]
+	].each do |fn, rx, idx|
+		file = File.expand_path fn
+		if File.readable?(file) and File.read(file) =~ rx
+			parse_options[:authors][user] = Regexp.last_match(idx).strip
+			break
+		end
+	end
+end
+
+if user and not user.empty? and not parse_options[:authors].has_key?(user)
+	name = ENV['GIT_AUTHOR_NAME'] || ''
+	name.replace(`git config user.name`.chomp) if name.empty?
+	name.replace(Etc.getpwnam(user).gecos) if name.empty?
+
+	if name.empty?
+		# couldn't find a name, try to steal data from other sources
+		steal_username
+	else
+		# if we found a name, try to find an email too
+		email = ENV['GIT_AUTHOR_EMAIL'] || ''
+		email.replace(`git config user.email`.chomp) if email.empty?
+
+		if email.empty?
+			# couldn't find an email, try to steal data too
+			steal_username
+		else
+			# we got both a name and email, fill the info
+			parse_options[:authors][user] = "#{name} <#{email}>"
+		end
+	end
+end
+
 if file_list.empty?
 	usage
 	exit 1
-- 
2.32.0.93.g670b81a890