Extract lscolors into its own python project.

lscolors/lscolors.py

@@ -0,0 +1,135 @@
+
+
+
+"""Give coloring for file types as in the ls command."""
+
+
+import os
+import os.path
+import stat
+import syslog
+
+
+FILE_KEY = "fi"
+DIRECTORY_KEY = "di"
+OTHER_WRITABLE_KEY = "ow"
+EXECUTABLE_KEY = "ex"
+SETUID_KEY = "su"
+SETGUID_KEY = "sg"
+SYMLINK_KEY = "ln"
+ORPHAN_KEY = "or"
+PIPE_KEY = "pi"
+CHARACTER_DEVICE_KEY = "cd"
+BLOCK_DEVICE_KEY = "bd"
+STICKY_KEY = "st"
+STICKY_OTHER_WRITABLE_KEY = "tw"
+SOCKET_KEY = "so"
+MISSING_KEY = "mi"
+MULTI_HARDLINK_KEY = "mh"
+
+
+def _parse_ls_colors(ls_codes):
+    color_codes = {}
+    for entry in ls_codes.split(":"):
+        if "=" not in entry:
+            continue
+        entry_key, entry_value = entry.split("=")
+        if entry_key.startswith("*."):
+            entry_key = entry_key[1:]
+        color_codes[entry_key] = entry_value
+    assert color_codes != {}, color_codes
+    return color_codes
+
+
+_DEFAULT_COLOR_CODES = \
+    {BLOCK_DEVICE_KEY: '01;33', SYMLINK_KEY: '01;36',
+     STICKY_OTHER_WRITABLE_KEY: '30;42', DIRECTORY_KEY: '01;34',
+     SETUID_KEY: '37;41', CHARACTER_DEVICE_KEY: '01;33', SOCKET_KEY: '01;35',
+     EXECUTABLE_KEY: '01;32', STICKY_KEY: '37;44',
+     OTHER_WRITABLE_KEY: '34;42', PIPE_KEY: '33', SETGUID_KEY: '30;43',
+     ORPHAN_KEY: '40;31;01'}
+
+
+def get_color_codes(environment):
+    """Get a dictionary of the color of every file type."""
+    if "LS_COLORS" in environment:
+        try:
+            return _parse_ls_colors(environment["LS_COLORS"])
+        except Exception:
+            syslog.syslog("Syntax error in LS_COLORS environment variable. "
+                          "Using default colors.")
+    return _DEFAULT_COLOR_CODES
+
+
+def color_key_for_path(path, color_codes, is_link_target=True):
+    """Get the high level type (key) of a file."""
+    # see print_color_indicator in the file 'ls.c' in the coreutils codebase
+    if not os.path.lexists(path):
+        return MISSING_KEY
+    elif os.path.islink(path):
+        if is_link_target:
+            try:
+                link_path = os.path.join(os.path.dirname(path),
+                                         os.readlink(path))
+                file_stat = os.stat(link_path)
+            except OSError:
+                return ORPHAN_KEY
+        else:
+            return SYMLINK_KEY
+    else:
+        file_stat = os.stat(path)
+    mode = file_stat.st_mode
+    if stat.S_ISREG(mode):
+        if mode & stat.S_ISUID and SETUID_KEY in color_codes:
+            return SETUID_KEY
+        elif mode & stat.S_ISGID and SETGUID_KEY in color_codes:
+            return SETGUID_KEY
+        elif ((mode & stat.S_IXUSR or mode & stat.S_IXGRP or
+               mode & stat.S_IXOTH) and EXECUTABLE_KEY in color_codes):
+            return EXECUTABLE_KEY
+        elif file_stat.st_nlink > 1 and MULTI_HARDLINK_KEY in color_codes:
+            return MULTI_HARDLINK_KEY
+        else:
+            return FILE_KEY
+    elif stat.S_ISDIR(mode):
+        if (mode & stat.S_ISVTX and mode & stat.S_IWOTH and
+                STICKY_OTHER_WRITABLE_KEY in color_codes):
+            return STICKY_OTHER_WRITABLE_KEY
+        elif (mode & stat.S_IWOTH) != 0 and OTHER_WRITABLE_KEY in color_codes:
+            return OTHER_WRITABLE_KEY
+        elif (mode & stat.S_ISVTX) != 0 and STICKY_KEY in color_codes:
+            return STICKY_KEY
+        else:
+            return DIRECTORY_KEY
+    for test_function, color_key in [(stat.S_ISFIFO, PIPE_KEY),
+                                     (stat.S_ISSOCK, SOCKET_KEY),
+                                     (stat.S_ISBLK, BLOCK_DEVICE_KEY),
+                                     (stat.S_ISCHR, CHARACTER_DEVICE_KEY)]:
+        if test_function(mode):
+            return color_key
+    return ORPHAN_KEY
+
+
+def color_code_for_path(path, color_codes):
+    """Get the color of a file."""
+    def get_extension(basename, color_codes):
+        parts = basename.split(".")
+        if len(parts) == 2:
+            extension = "." + parts[1]
+            if extension in color_codes:
+                return extension
+        elif len(parts) > 2:
+            for extension in color_codes:
+                if extension.startswith(".") and \
+                   basename.endswith(extension):
+                    return extension
+    target_link = color_codes.get(SYMLINK_KEY, None)
+    color_key = color_key_for_path(path, color_codes,
+                                   target_link == "target")
+    if color_key == FILE_KEY:
+        filename = os.path.basename(path)
+        if "." in filename:
+            extension = get_extension(filename, color_codes)
+            if extension is not None:
+                color_key = extension
+    return color_codes.get(color_key, None)