From ce11e97f013485bdedd834b960c88a1452701648 Mon Sep 17 00:00:00 2001
From: Xi Ruoyao <xry111@xry111.site>
Date: Tue, 6 Feb 2024 00:15:33 +0800
Subject: [PATCH 1/3] kernfs: Use a separate devpts filesystem for chroot
 environment

IIRC we switched from separate devpts to bind mount, and matched the UID
of tester with the host UID owning the TTY, to satisify the Bash test
suite.  But now we are always using UID 101 for tester and expect to
spawn a PTY for Bash test suite (so when building LFS in a TTY owned by
the root user of the host tester won't be UID 0).  Thus we can switch
back to a separate devpts mount which is cleaner and safer.

And we are already using a separate devpts mount in Chapter 11.
---
 chapter07/kernfs.xml | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/chapter07/kernfs.xml b/chapter07/kernfs.xml
index 575044106..067a614f4 100644
--- a/chapter07/kernfs.xml
+++ b/chapter07/kernfs.xml
@@ -63,11 +63,14 @@
 
       <para>Now mount the remaining virtual kernel file systems:</para>
 
-<screen><userinput>mount -v --bind /dev/pts $LFS/dev/pts
+      <!-- Do not put any option after $LFS/${mountpoint} or jhalfs cannot
+           handle it! -->
+
+<screen><userinput>mount -vt devpts devpts -o gid=5,mode=0620 $LFS/dev/pts
 mount -vt proc proc $LFS/proc
 mount -vt sysfs sysfs $LFS/sys
 mount -vt tmpfs tmpfs $LFS/run</userinput></screen>
-<!--
+
     <variablelist>
       <title>The meaning of the mount options for devpts:</title>
 
@@ -95,7 +98,7 @@ mount -vt tmpfs tmpfs $LFS/run</userinput></screen>
       </varlistentry>
 
     </variablelist>
--->
+
       <para>In some host systems, <filename>/dev/shm</filename> is a
       symbolic link to a directory, typically
       <filename class="directory">/run/shm</filename>.

From 1fde756b121ffcba522f252475418714240358c7 Mon Sep 17 00:00:00 2001
From: Xi Ruoyao <xry111@xry111.site>
Date: Tue, 6 Feb 2024 01:00:53 +0800
Subject: [PATCH 2/3] expect: Add (back) a simple test for PTY

We used to run "expect -c 'spawn ls'" for this in Binutils, but then we
thought expect test suite was enough as such a simple PTY test.  However
expect test can fail due to some different reason, so add back a simple
test using Python pty module before building expect.  Now we no longer
need to consider expect test critical (IIRC there was a report saying
one expect test failed for unknown reason but all other things OK).
---
 chapter08/expect.xml | 36 +++++++++++++++++++-----------------
 1 file changed, 19 insertions(+), 17 deletions(-)

diff --git a/chapter08/expect.xml b/chapter08/expect.xml
index 810bc55a2..5c21e390f 100644
--- a/chapter08/expect.xml
+++ b/chapter08/expect.xml
@@ -48,6 +48,25 @@
   <sect2 role="installation">
     <title>Installation of Expect</title>
 
+    <para>Expect needs PTYs to work.  Verify that the PTYs are working
+    properly inside the chroot environment by performing a simple
+    test:</para>
+
+<screen><userinput remap="test">python3 -c 'from pty import spawn; spawn(["echo", "ok"])'</userinput></screen>
+
+    <para>This command should output <computeroutput>ok</computeroutput>.
+    If, instead, the output includes <computeroutput>OSError: out of pty
+    devices</computeroutput>, then the environment is not set up for proper
+    PTY operation.  You need to exit from the chroot environment, read
+    <xref linkend='ch-tools-kernfs'/> again, and ensure the
+    <systemitem class="filesystem">devpts</systemitem> file system (and
+    other virtual kernel file systems) mounted correctly.  Then reenter
+    the chroot environment following <xref linkend='ch-tools-chroot'/>.
+    This issue needs to be resolved before continuing, or the test suites
+    requring Expect (for example the test suites of Bash, Binutils, GCC,
+    GDBM, and of course Expect itself) will fail catastrophically, and other
+    subtle breakages may also happen.</para>
+
     <para>Prepare Expect for compilation:</para>
 
 <screen><userinput remap="configure">./configure --prefix=/usr           \
@@ -82,27 +101,10 @@
 
 <screen><userinput remap="make">make</userinput></screen>
 
-    <important>
-      <para>The test suite for Expect is considered critical.
-      Do not skip it under any circumstances.</para>
-    </important>
-
     <para>To test the results, issue:</para>
 
 <screen><userinput remap="test">make test</userinput></screen>
 
-    <para>If any test fails with the message
-    <computeroutput>The system has no more ptys. Ask your system
-    administrator to create more</computeroutput>, it indicates
-    you've not mounted the
-    <systemitem class="filesystem">devpts</systemitem> file system
-    correctly.  You need to exit from the chroot environment, read
-    <xref linkend='ch-tools-kernfs'/> again, and ensure the
-    <systemitem class="filesystem">devpts</systemitem> file system (and
-    other virtual kernel file systems) mounted correctly.  Then reenter
-    the chroot environment following <xref linkend='ch-tools-chroot'/>.
-    This issue needs to be resolved before continuing.</para>
-
     <para>Install the package:</para>
 
 <screen><userinput remap="install">make install

From 4816dc69f596e962ecb050fdfea3704e65514a47 Mon Sep 17 00:00:00 2001
From: Xi Ruoyao <xry111@xry111.site>
Date: Tue, 6 Feb 2024 03:44:38 +0800
Subject: [PATCH 3/3] bash: Really pass through the return code

We want expect to return the return code of "make test" (stored in
$value), but $value is expanded too early to nothing by Bash.  Quote EOF
so Bash won't expand $xxx.
---
 chapter08/bash.xml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/chapter08/bash.xml b/chapter08/bash.xml
index 4b5b47e62..1490e7791 100644
--- a/chapter08/bash.xml
+++ b/chapter08/bash.xml
@@ -83,7 +83,7 @@
     <application>Expect</application> and run the tests as the <systemitem
     class="username">tester</systemitem> user:</para>
 
-<screen><userinput remap="test">su -s /usr/bin/expect tester &lt;&lt; EOF
+<screen><userinput remap="test">su -s /usr/bin/expect tester &lt;&lt; "EOF"
 set timeout -1
 spawn make tests
 expect eof