snagrecover: config: Allow a 'paths-relative-to' key in the firmware

configs

paths-relative-to can be CWD, THIS_FILE, or a literal path. It defaults
to CWD.

The firmware configs will be patched accordingly: binary paths will be
prefixed by either the current working directory (this is the old
behaviour), the directory containing the firmware config file, or the
literal path.

Author: Salamandar

src/snagrecover/config.py

@@ -17,6 +17,7 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 
+import os
 import yaml
 from snagrecover.utils import (
 	cli_error,
@@ -76,6 +77,20 @@ def check_soc_model(soc_model: str):
 	return None
 
 
+def patch_firmware_image_paths(fw_config: dict, this_file_path: str) -> dict:
+    paths_relative_to_conf = fw_config.pop("paths-relative-to", "CWD")
+    if paths_relative_to_conf == "CWD":
+        path_relative_to = os.getcwd()
+    elif paths_relative_to_conf == "THIS_FILE":
+        path_relative_to = os.path.dirname(this_file_path)
+    else:
+        path_relative_to = path_relative_to_conf
+
+    for binary in fw_config.keys():
+        if "path" in fw_config[binary]:
+            fw_config[binary]["path"] = os.path.join(path_relative_to, fw_config[binary]["path"])
+
+
 def init_config(args: list):
 	# this is the only time that config.recovery_config should be modified!
 	# get soc model
@@ -127,6 +142,7 @@ def init_config(args: list):
 				cli_error(
 					f"firmware config passed to CLI did not evaluate to dict: {fw_configs}"
 				)
+			fw_config_file = patch_firmware_image_paths(fw_config_file, path)
 			fw_configs = {**fw_configs, **fw_config_file}
 		recovery_config["firmware"] = fw_configs