Revert "terminal.bbclass: use var-SHELL as the shebang of wrapper script"

The $SHELL environment variable is used for the user's preferred interactive shell. This shall not be used when executing shell scripts that expect POSIX shell syntax as there is no guarantee that it is a POSIX compatible shell.

This reverts commit 27e2ede65f1193e49f9483b08a55495d88740a65.

---

In my case, $SHELL is set to /bin/zsh, with the result that devshell fails to start. If there is some problem with devshell related to /bin/sh being linked to dash rather than bash (which the original commit indicates), then that should be adressed instead.

Hongxu: Do you have any additional information related to why you made the change in the first place?

 meta/classes/terminal.bbclass | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

index 73e765d57a..a27e10c6ec 100644
@@ -25,8 +25,7 @@ def emit_terminal_func(command, envdata, d):
     bb.utils.mkdirhier(os.path.dirname(runfile))
 
     with open(runfile, 'w') as script:
-        script.write('#!/usr/bin/env %s\n' % d.getVar('SHELL'))
-        script.write('set -e\n')
+        script.write('#!/bin/sh -e\n')
         bb.data.emit_func(cmd_func, script, envdata)
         script.write(cmd_func)
         script.write("\n")

2.12.0

There is a sanity check to `/bin/sh' to dash or bash

`eaa0dc2 sanity.bbclass: Only verify /bin/sh link if it's a link'

`ecdfdd7 sanity.bbclass: check /bin/sh is dash or bash'

If revert this patch, we will have the issue which this patch have fixed.

There is another patch in mailing list that fix the issue you report

[OE-core] [PATCH] devshell.bbclass/terminal.bbclass: add a shell check at devshell

While var-SHELL is neither bash' or dash', such as csh', loading the wrapper script will fail at devshell, because csh does not support syntax export'.

Add a shell check at devshell, and use /bin/sh' to replace if shell is neither bash' or dash'. /bin/sh' is safe to use since `ecdfdd7 sanity.bbclass: check /bin/sh is dash or bash'

---
 meta/classes/devshell.bbclass | 4 ++++
 meta/classes/terminal.bbclass | 4 +++-

 2 files changed, 7 insertions(+), 1 deletion(-)

index fdf7dc1..c4765db 100644
@@ -3,6 +3,10 @@ inherit terminal

 DEVSHELL = "${SHELL}"

 python do_devshell () {
+    devshell = d.getVar('DEVSHELL')
+    devshell = devshell if devshell.endswith("bash") or devshell.endswith("dash") else '/bin/sh' +    d.setVar('DEVSHELL', devshell)
+
     if d.getVarFlag("do_devshell", "manualfakeroot"):
        d.prependVar("DEVSHELL", "pseudo ")
        fakeenv = d.getVar("FAKEROOTENV").split()

index 73e765d..f427538 100644
@@ -25,7 +25,9 @@ def emit_terminal_func(command, envdata, d):

     bb.utils.mkdirhier(os.path.dirname(runfile))

     with open(runfile, 'w') as script:
-        script.write('#!/usr/bin/env %s\n' % d.getVar('SHELL'))
+        shell = d.getVar('SHELL')
+        shell = shell if shell.endswith("bash") or shell.endswith("dash") else '/bin/sh' +        script.write('#!/usr/bin/env %s\n' % shell)
         script.write('set -e\n')
         bb.data.emit_func(cmd_func, script, envdata) script.write(cmd_func)

//Hongxu