Merge branch 'bc/send-email-auto-cte'

The content-transfer-encoding of the message "git send-email" sends
out by default was 8bit, which can cause trouble when there is an
overlong line to bust RFC 5322/2822 limit.  A new option 'auto' to
automatically switch to quoted-printable when there is such a line
in the payload has been introduced and is made the default.

* bc/send-email-auto-cte:
docs: correct RFC specifying email line length
send-email: automatically determine transfer-encoding
send-email: accept long lines with suitable transfer encoding
send-email: add an auto option for transfer encoding

diff --git a/Documentation/git-send-email.txt b/Documentation/git-send-email.txt
index 4f3efde80cd8e4f0b1a5b6699ad3e569f19ca516..465a4ecbeddaa20189bce6e223df8bbfa0319b9a 100644 (file)
--- a/Documentation/git-send-email.txt
+++ b/Documentation/git-send-email.txt
@@ -137,15 +137,17 @@ Note that no attempts whatsoever are made to validate the encoding.
        Specify encoding of compose message. Default is the value of the
        'sendemail.composeencoding'; if that is unspecified, UTF-8 is assumed.
 
---transfer-encoding=(7bit|8bit|quoted-printable|base64)::
+--transfer-encoding=(7bit|8bit|quoted-printable|base64|auto)::
        Specify the transfer encoding to be used to send the message over SMTP.
        7bit will fail upon encountering a non-ASCII message.  quoted-printable
        can be useful when the repository contains files that contain carriage
        returns, but makes the raw patch email file (as saved from a MUA) much
        harder to inspect manually.  base64 is even more fool proof, but also
-       even more opaque.  Default is the value of the `sendemail.transferEncoding`
-       configuration value; if that is unspecified, git will use 8bit and not
-       add a Content-Transfer-Encoding header.
+       even more opaque.  auto will use 8bit when possible, and quoted-printable
+       otherwise.
++
+Default is the value of the `sendemail.transferEncoding` configuration
+value; if that is unspecified, default to `auto`.
 
 --xmailer::
 --no-xmailer::
@@ -398,8 +400,11 @@ have been specified, in which case default to 'compose'.
 +
 --
                *       Invoke the sendemail-validate hook if present (see linkgit:githooks[5]).
-               *       Warn of patches that contain lines longer than 998 characters; this
-                       is due to SMTP limits as described by http://www.ietf.org/rfc/rfc2821.txt.
+               *       Warn of patches that contain lines longer than
+                       998 characters unless a suitable transfer encoding
+                       ('auto', 'base64', or 'quoted-printable') is used;
+                       this is due to SMTP limits as described by
+                       http://www.ietf.org/rfc/rfc5322.txt.
 --
 +
 Default is the value of `sendemail.validate`; if this is not set,

diff --git a/git-send-email.perl b/git-send-email.perl
index 8ec70e58ed5c4caace7701549038b63f9a3e9aad..f4c07908d2737203031bdcab7f4f30404e64d4e5 100755 (executable)
--- a/git-send-email.perl
+++ b/git-send-email.perl
@@ -231,7 +231,7 @@ sub do_edit {
 my (@suppress_cc);
 my ($auto_8bit_encoding);
 my ($compose_encoding);
-my ($target_xfer_encoding);
+my $target_xfer_encoding = 'auto';
 
 my ($debug_net_smtp) = 0;              # Net::SMTP, see send_message()
 
@@ -645,7 +645,7 @@ sub is_format_patch_arg {
 if ($validate) {
        foreach my $f (@files) {
                unless (-p $f) {
-                       my $error = validate_patch($f);
+                       my $error = validate_patch($f, $target_xfer_encoding);
                        $error and die sprintf(__("fatal: %s: %s\nwarning: no patches were sent\n"),
                                                  $f, $error);
                }
@@ -1737,18 +1737,11 @@ sub process_file {
                        }
                }
        }
-       if (defined $target_xfer_encoding) {
-               $xfer_encoding = '8bit' if not defined $xfer_encoding;
-               $message = apply_transfer_encoding(
-                       $message, $xfer_encoding, $target_xfer_encoding);
-               $xfer_encoding = $target_xfer_encoding;
-       }
-       if (defined $xfer_encoding) {
-               push @xh, "Content-Transfer-Encoding: $xfer_encoding";
-       }
-       if (defined $xfer_encoding or $has_content_type) {
-               unshift @xh, 'MIME-Version: 1.0' unless $has_mime_version;
-       }
+       $xfer_encoding = '8bit' if not defined $xfer_encoding;
+       ($message, $xfer_encoding) = apply_transfer_encoding(
+               $message, $xfer_encoding, $target_xfer_encoding);
+       push @xh, "Content-Transfer-Encoding: $xfer_encoding";
+       unshift @xh, 'MIME-Version: 1.0' unless $has_mime_version;
 
        $needs_confirm = (
                $confirm eq "always" or
@@ -1852,13 +1845,16 @@ sub apply_transfer_encoding {
        $message = MIME::Base64::decode($message)
                if ($from eq 'base64');
 
+       $to = ($message =~ /.{999,}/) ? 'quoted-printable' : '8bit'
+               if $to eq 'auto';
+
        die __("cannot send message as 7bit")
                if ($to eq '7bit' and $message =~ /[^[:ascii:]]/);
-       return $message
+       return ($message, $to)
                if ($to eq '7bit' or $to eq '8bit');
-       return MIME::QuotedPrint::encode($message, "\n", 0)
+       return (MIME::QuotedPrint::encode($message, "\n", 0), $to)
                if ($to eq 'quoted-printable');
-       return MIME::Base64::encode($message, "\n")
+       return (MIME::Base64::encode($message, "\n"), $to)
                if ($to eq 'base64');
        die __("invalid transfer encoding");
 }
@@ -1877,7 +1873,7 @@ sub unique_email_list {
 }
 
 sub validate_patch {
-       my $fn = shift;
+       my ($fn, $xfer_encoding) = @_;
 
        if ($repo) {
                my $validate_hook = catfile(catdir($repo->repo_path(), 'hooks'),
@@ -1897,11 +1893,15 @@ sub validate_patch {
                return $hook_error if $hook_error;
        }
 
-       open(my $fh, '<', $fn)
-               or die sprintf(__("unable to open %s: %s\n"), $fn, $!);
-       while (my $line = <$fh>) {
-               if (length($line) > 998) {
-                       return sprintf(__("%s: patch contains a line longer than 998 characters"), $.);
+       # Any long lines will be automatically fixed if we use a suitable transfer
+       # encoding.
+       unless ($xfer_encoding =~ /^(?:auto|quoted-printable|base64)$/) {
+               open(my $fh, '<', $fn)
+                       or die sprintf(__("unable to open %s: %s\n"), $fn, $!);
+               while (my $line = <$fh>) {
+                       if (length($line) > 998) {
+                               return sprintf(__("%s: patch contains a line longer than 998 characters"), $.);
+                       }
                }
        }
        return;

diff --git a/t/t9001-send-email.sh b/t/t9001-send-email.sh
index e80eacbb1b81a319232c0b5f28aab3c82d795a93..1da282c415b81215ddb149f6230ff2a5a8eb4c95 100755 (executable)
--- a/t/t9001-send-email.sh
+++ b/t/t9001-send-email.sh
@@ -225,6 +225,8 @@ X-Mailer: X-MAILER-STRING
 In-Reply-To: <unique-message-id@example.com>
 References: <unique-message-id@example.com>
 Reply-To: Reply <reply@example.com>
+MIME-Version: 1.0
+Content-Transfer-Encoding: 8bit
 
 Result: OK
 EOF
@@ -415,6 +417,7 @@ test_expect_success $PREREQ 'reject long lines' '
                --from="Example <nobody@example.com>" \
                --to=nobody@example.com \
                --smtp-server="$(pwd)/fake.sendmail" \
+               --transfer-encoding=8bit \
                $patches longline.patch \
                2>errors &&
        grep longline.patch errors
@@ -456,6 +459,42 @@ test_expect_success $PREREQ 'allow long lines with --no-validate' '
                2>errors
 '
 
+test_expect_success $PREREQ 'short lines with auto encoding are 8bit' '
+       clean_fake_sendmail &&
+       git send-email \
+               --from="A <author@example.com>" \
+               --to=nobody@example.com \
+               --smtp-server="$(pwd)/fake.sendmail" \
+               --transfer-encoding=auto \
+               $patches &&
+       grep "Content-Transfer-Encoding: 8bit" msgtxt1
+'
+
+test_expect_success $PREREQ 'long lines with auto encoding are quoted-printable' '
+       clean_fake_sendmail &&
+       git send-email \
+               --from="Example <nobody@example.com>" \
+               --to=nobody@example.com \
+               --smtp-server="$(pwd)/fake.sendmail" \
+               --transfer-encoding=auto \
+               --no-validate \
+               longline.patch &&
+       grep "Content-Transfer-Encoding: quoted-printable" msgtxt1
+'
+
+for enc in auto quoted-printable base64
+do
+       test_expect_success $PREREQ "--validate passes with encoding $enc" '
+               git send-email \
+                       --from="Example <nobody@example.com>" \
+                       --to=nobody@example.com \
+                       --smtp-server="$(pwd)/fake.sendmail" \
+                       --transfer-encoding=$enc \
+                       --validate \
+                       $patches longline.patch
+       '
+done
+
 test_expect_success $PREREQ 'Invalid In-Reply-To' '
        clean_fake_sendmail &&
        git send-email \
@@ -573,6 +612,8 @@ Subject: [PATCH 1/1] Second.
 Date: DATE-STRING
 Message-Id: MESSAGE-ID-STRING
 X-Mailer: X-MAILER-STRING
+MIME-Version: 1.0
+Content-Transfer-Encoding: 8bit
 
 Result: OK
 EOF
@@ -617,6 +658,8 @@ Subject: [PATCH 1/1] Second.
 Date: DATE-STRING
 Message-Id: MESSAGE-ID-STRING
 X-Mailer: X-MAILER-STRING
+MIME-Version: 1.0
+Content-Transfer-Encoding: 8bit
 
 Result: OK
 EOF
@@ -652,6 +695,8 @@ Subject: [PATCH 1/1] Second.
 Date: DATE-STRING
 Message-Id: MESSAGE-ID-STRING
 X-Mailer: X-MAILER-STRING
+MIME-Version: 1.0
+Content-Transfer-Encoding: 8bit
 
 Result: OK
 EOF
@@ -678,6 +723,8 @@ Subject: [PATCH 1/1] Second.
 Date: DATE-STRING
 Message-Id: MESSAGE-ID-STRING
 X-Mailer: X-MAILER-STRING
+MIME-Version: 1.0
+Content-Transfer-Encoding: 8bit
 
 Result: OK
 EOF
@@ -712,6 +759,8 @@ Subject: [PATCH 1/1] Second.
 Date: DATE-STRING
 Message-Id: MESSAGE-ID-STRING
 X-Mailer: X-MAILER-STRING
+MIME-Version: 1.0
+Content-Transfer-Encoding: 8bit
 
 Result: OK
 EOF
@@ -743,6 +792,8 @@ Subject: [PATCH 1/1] Second.
 Date: DATE-STRING
 Message-Id: MESSAGE-ID-STRING
 X-Mailer: X-MAILER-STRING
+MIME-Version: 1.0
+Content-Transfer-Encoding: 8bit
 
 Result: OK
 EOF
@@ -774,6 +825,8 @@ Subject: [PATCH 1/1] Second.
 Date: DATE-STRING
 Message-Id: MESSAGE-ID-STRING
 X-Mailer: X-MAILER-STRING
+MIME-Version: 1.0
+Content-Transfer-Encoding: 8bit
 
 Result: OK
 EOF
@@ -809,6 +862,8 @@ Subject: [PATCH 1/1] Second.
 Date: DATE-STRING
 Message-Id: MESSAGE-ID-STRING
 X-Mailer: X-MAILER-STRING
+MIME-Version: 1.0
+Content-Transfer-Encoding: 8bit
 
 Result: OK
 EOF
@@ -837,6 +892,8 @@ Subject: [PATCH 1/1] Second.
 Date: DATE-STRING
 Message-Id: MESSAGE-ID-STRING
 X-Mailer: X-MAILER-STRING
+MIME-Version: 1.0
+Content-Transfer-Encoding: 8bit
 
 Result: OK
 EOF