Added utility module with common functions

fs_uae_wrapper/utils.py

@@ -1,11 +1,16 @@
 """
 Misc utilities
 """
+from distutils import spawn
 import os
 import subprocess
 import sys
+try:
+    import configparser
+except ImportError:
+    import ConfigParser as configparser
 
-from fs_uae_wrapper.wrapper import WRAPPER_KEY
+from fs_uae_wrapper import WRAPPER_KEY
 
 
 ARCHIVERS = {'.tar': ['tar', 'xf'],
@@ -20,6 +25,19 @@ ARCHIVERS = {'.tar': ['tar', 'xf'],
              '.lzx':  ['unlzx']}
 
 
+def get_config_options(conf):
+    """Read config file and return options as a dict"""
+    parser = configparser.SafeConfigParser()
+    try:
+        parser.read(conf)
+    except configparser.ParsingError:
+        # Configuration syntax is wrong
+        return None
+
+    return {key: val for section in parser.sections()
+            for key, val in parser.items(section)}
+
+
 def extract_archive(arch_name):
     """
     Extract provided archive to current directory
@@ -46,7 +64,7 @@ def extract_archive(arch_name):
     return True
 
 
-def merge_options(configuration, wrapper_options):
+def merge_wrapper_options(configuration, wrapper_options):
     """
     Merge dictionaries with wrapper options into one. Commandline options
     have precedence.
@@ -59,3 +77,114 @@ def merge_options(configuration, wrapper_options):
     options.update(wrapper_options)
 
     return options
+
+
+def options_to_dict(commandline):
+    """
+    "Parse" commandline switches and return them as dictionary
+    """
+    options = {}
+    for option in commandline:
+        if option.startswith('--'):
+            if '=' in option:
+                key, val = option[2:].split('=')
+                options[key.strip()] = val.strip()
+            else:
+                options[option[2:].strip()] = '1'
+
+    return options
+
+
+def merge_all_options(configuration, commandline):
+    """
+    Merge dictionaries with wrapper options into one. Commandline options
+    have precedence.
+    """
+    options = {}
+    for key, val in configuration:
+        options[key] = val
+
+    options.update(options_to_dict(commandline))
+
+    return options
+
+
+def interpolate_variables(string, config_path, base=None):
+    """
+    Interpolate variables used in fs-uae configuration files, like:
+        - $CONFIG
+        - $HOME
+        - $EXE
+        - $APP
+        - $DOCUMENTS
+        - $BASE
+    """
+
+    if '$CONFIG' in string:
+        string = string.replace('$CONFIG',
+                                os.path.dirname(os.path.abspath(config_path)))
+    if '$HOME' in string:
+        string = string.replace('$HOME', os.path.expandvars('$HOME'))
+
+    if '$EXE' in string:
+        string = string.replace('$EXE', spawn.find_executable('fs-uae'))
+
+    if '$APP' in string:
+        string = string.replace('$APP', spawn.find_executable('fs-uae'))
+
+    if '$DOCUMENTS' in string:
+        xdg_docs = os.getenv('XDG_DOCUMENTS_DIR',
+                             os.path.expanduser('~/Documents'))
+        string = string.replace('$DOCUMENTS', xdg_docs)
+
+    if base:
+        if '$BASE' in string:
+            string = string.replace('$BASE', base)
+
+    return string
+
+
+def get_config(conf_file):
+    """
+    Try to find configuration files and collect data from it.
+    Will search for paths described in https://fs-uae.net/paths
+    - ~/Documents/FS-UAE/Configurations/Default.fs-uae
+    - ~/Documents/FS-UAE/Configurations/Host.fs-uae
+    - ~/FS-UAE/Configurations/Default.fs-uae
+    - ~/FS-UAE/Configurations/Host.fs-uae
+    - ~/.config/fs-uae/fs-uae.conf
+    - ./fs-uae.conf
+    - ./Config.fs-uae
+    """
+
+    xdg_conf = os.getenv('XDG_CONFIG_HOME', os.path.expanduser('~/.config'))
+    user = os.path.expanduser('~/')
+    paths = ((os.path.join(xdg_conf, 'fs-uae/fs-uae.conf'),
+              os.path.join(xdg_conf, 'fs-uae/')),
+             (os.path.join(user,
+                           'Documents/FS-UAE/Configurations/Default.fs-uae'),
+              os.path.join(user, 'Documents/FS-UAE')),
+             (os.path.join(user, 'FS-UAE/Configurations/Default.fs-uae'),
+              os.path.join(user, 'FS-UAE')))
+
+    for path, conf_dir in paths:
+        if os.path.exists(path):
+            config = get_config_options(path)
+            config.update(get_config_options(conf_file))
+            break
+    else:
+        conf_dir = None
+        config = get_config_options(conf_file)
+
+    if 'base_dir' in config:
+        base_dir = interpolate_variables(config['base_dir'], conf_file)
+        host = os.path.join(base_dir, 'Configurations/Host.fs-uae')
+
+        if os.path.exists(host):
+            config.update(get_config_options(host))
+            # overwrite host options again via provided custom/relative conf
+            config.update(get_config_options(conf_file))
+    elif conf_dir:
+        config['_base_dir'] = conf_dir
+
+    return config