pmbootstrap init: ask for work folder before asking for device (#1068)

This fixes #1066, where pmbootstrap crashes with a permission error
when you run it for the first time (no work folder exists) and you
run the boot.img analyzer because you want to start a new device
port.

It also prints a more helpful message if pmbootstrap crashes before
the log file was generated (suggests to use --details-to-stdout).

pmb/__init__.py

@@ -65,7 +65,12 @@ def main():
 
     except Exception as e:
         logging.info("ERROR: " + str(e))
-        logging.info("Run 'pmbootstrap log' for details.")
+        if os.path.exists(args.log):
+            logging.info("Run 'pmbootstrap log' for details.")
+        else:
+            logging.info("Crashed before the log file was created.")
+            logging.info("Running init again like the following gives more details:")
+            logging.info("    pmbootstrap --details-to-stdout init")
         logging.info("See also: <https://postmarketos.org/troubleshooting>")
         logging.debug(traceback.format_exc())
         return 1

pmb/config/init.py

@@ -201,6 +201,9 @@ def ask_for_build_options(args, cfg):
 def frontend(args):
     cfg = pmb.config.load(args)
 
+    # Work folder (needs to be first, so boot.img analyze works: #1066)
+    cfg["pmbootstrap"]["work"] = args.work = ask_for_work_path(args)
+
     # Device
     cfg["pmbootstrap"]["device"], device_exists = ask_for_device(args)
 
@@ -217,11 +220,8 @@ def frontend(args):
     cfg["pmbootstrap"]["user"] = pmb.helpers.cli.ask(args, "Username", None,
                                                      args.user, False,
                                                      "[a-z_][a-z0-9_-]*")
-    # UI and work folder
+    # UI and various build options
     cfg["pmbootstrap"]["ui"] = ask_for_ui(args)
-    cfg["pmbootstrap"]["work"] = ask_for_work_path(args)
-
-    # Various build options
     ask_for_build_options(args, cfg)
 
     # Extra packages to be installed to rootfs