diff --git a/scripts/update-source-file-header.py b/scripts/update-source-file-header.py
index 80b896a8..eb226f90 100644
--- a/scripts/update-source-file-header.py
+++ b/scripts/update-source-file-header.py
@@ -1,96 +1,150 @@
 #!/usr/bin/env python3
+# MobileGL - scripts/update-source-file-header.py
+# Copyright (c) 2025-2026 MobileGL-Dev
+# Licensed under the GNU Lesser General Public License v3.0:
+#   https://www.gnu.org/licenses/gpl-3.0.txt
+#   https://www.gnu.org/licenses/lgpl-3.0.txt
+# SPDX-License-Identifier: LGPL-3.0-only
+# End of Source File Header
+"""Add the license header to source files that lack it.
+
+    python3 scripts/update-source-file-header.py             # every tracked source file it covers
+    python3 scripts/update-source-file-header.py FILE ...     # only these files
+    python3 scripts/update-source-file-header.py --check      # list what needs attention, exit 1 if anything does
+
+Covered under MobileGL/, scripts/ and tools/: C, C++ and .inc files with // comments and Python
+scripts with # comments.
+An existing header is kept as written, since its copyright years belong to the file; only a first
+line that names a different path is corrected. Generated files and files under another license are
+left alone. Files with mixed line endings are reported, never rewritten.
+"""
+
 import os
+import re
+import subprocess
 import sys
-import pathlib
-from glob import glob
 
-try:
-    import colorama
-    colorama.init()
-    CYAN = colorama.Fore.CYAN + colorama.Style.BRIGHT
-    GREEN = colorama.Fore.GREEN
-    YELLOW = colorama.Fore.YELLOW
-    RED = colorama.Fore.RED
-    RESET = colorama.Style.RESET_ALL
-except ImportError:
-    CYAN = GREEN = YELLOW = RED = RESET = ''
-
-OK = "✔"
-FAIL = "✖"
-ARROW = "╰─>"
-SIMPLE_ARROW = "─>"
-
-HEADER_TEMPLATE = """// MobileGL - {file_path}
-// Copyright (c) 2025-2026 MobileGL-Dev
-// Licensed under the GNU Lesser General Public License v3.0:
-//   https://www.gnu.org/licenses/gpl-3.0.txt
-//   https://www.gnu.org/licenses/lgpl-3.0.txt
-// SPDX-License-Identifier: LGPL-3.0-only
-// End of Source File Header
+ROOT = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+MARKER = "End of Source File Header"
+HEADER = """{c} MobileGL - {path}
+{c} Copyright (c) 2025-2026 MobileGL-Dev
+{c} Licensed under the GNU Lesser General Public License v3.0:
+{c}   https://www.gnu.org/licenses/gpl-3.0.txt
+{c}   https://www.gnu.org/licenses/lgpl-3.0.txt
+{c} SPDX-License-Identifier: LGPL-3.0-only
+{c} End of Source File Header
 """
+OWN_SPDX = "SPDX-License-Identifier: LGPL-3.0-only"
+DIRS = ("MobileGL/", "scripts/", "tools/")
+SLASH_EXT = (".h", ".hpp", ".cpp", ".cc", ".c", ".inc")
+HASH_EXT = (".py",)
+FOREIGN_LICENSE = re.compile(r"Apache License|Permission is hereby granted|MIT License|BSD License|"
+                             r"Mozilla Public License|zlib License")
+SPDX_RE = re.compile(r"SPDX-License-Identifier:\s*(\S+)")
+COPYRIGHT_RE = re.compile(r"Copyright\b.*")
+# Built against apitrace's glws/glproc interfaces; whether they are adapted from apitrace's own
+# sources is not settled, so they carry no MobileGL header until it is.
+EXEMPT = ("tools/trace_replay/apitrace_",)
 
-HEADER_MARKER = """End of Source File Header
-"""
+# plan() statuses: the first three need no action, the last four do.
+QUIET = ("ok", "foreign", "empty")
+FIXABLE = ("add", "fix-path")
+MANUAL = ("mixed-eol", "bad-header")
 
-SCRIPT_DIR = pathlib.Path(__file__).parent.resolve()
-TARGET_DIR = SCRIPT_DIR / "../MobileGL"
-FILE_PATTERNS = ["*.h", "*.hpp", "*.cpp", "*.cc", "*.c"]
 
-if not TARGET_DIR.exists():
-    print(f"{YELLOW}Target directory '{TARGET_DIR}' does not exist.{RESET}")
-    sys.exit(1)
+def is_generated(path):
+    return "/generated/" in path or "/gen/" in path or os.path.basename(path).startswith("generated_")
 
-def find_source_files():
-    candidates = []
-    for root, dirs, files in os.walk(TARGET_DIR):
-        dirs[:] = [d for d in dirs if d not in ("build", "out")]
-        for pattern in FILE_PATTERNS:
-            for f in glob(os.path.join(root, pattern)):
-                candidates.append(f)
-    return candidates
 
-candidates = find_source_files()
-total = len(candidates)
-print(f"{YELLOW}Found {total} candidate(s).{RESET}")
+def comment_prefix(path):
+    if path.endswith(HASH_EXT):
+        return "#"
+    if path.endswith(SLASH_EXT):
+        return "//"
+    return None
 
-if total == 0:
-    sys.exit(0)
 
-def draw_progress(current, total, width=36):
-    percent = int(current * 100 / total) if total else 0
-    filled = int(current * width / total) if total else 0
-    empty = width - filled
-    bar = "█" * filled + "░" * empty
-    print(f"\r{CYAN}Progress{RESET} [{current}/{total}] {percent:3d}% |{bar}|", end='')
+def covered(path):
+    return (path.startswith(DIRS) and comment_prefix(path) is not None
+            and not is_generated(path) and not path.startswith(EXEMPT))
 
-processed = 0
-skipped = 0
-for idx, file_path in enumerate(candidates, start=1):
-    draw_progress(idx, total)
-    try:
-        with open(file_path, "r", encoding="utf-8", errors="ignore") as f:
-            content = f.read()
 
-        rel_path = os.path.relpath(file_path, SCRIPT_DIR.parent)
-        new_header = HEADER_TEMPLATE.format(file_path=rel_path.replace("\\", "/"))
+def plan(path, text):
+    """Return (status, new_text). new_text is set only for the FIXABLE statuses."""
+    if not text.strip():
+        return "empty", None
+    bom = "" if text.startswith("") else ""
+    text = text[len(bom):]
+    if "\r\n" in text and re.search(r"(?<!\r)\n", text):
+        return "mixed-eol", None
+    c = comment_prefix(path)
+    lines = text.splitlines(keepends=True)
+    eol = "\r\n" if lines[0].endswith("\r\n") else "\n"
+    prefix = []
+    while lines and (lines[0].startswith("#!") or (c == "#" and re.match(r"#.*coding[:=]", lines[0]))):
+        prefix.append(lines.pop(0))
 
-        if HEADER_MARKER in content:
-            rest = content.split(HEADER_MARKER, 1)[1]
-            new_content = new_header + rest
+    head = "".join(lines[:15])
+    if MARKER in head:
+        first = lines[0].rstrip("\r\n")
+        expected = "%s MobileGL - %s" % (c, path)
+        if OWN_SPDX not in head or not re.match(r"(//|#|/\*) MobileGL - ", first):
+            return "bad-header", None
+        if first.startswith(c + " MobileGL - ") and first != expected:
+            lines[0] = expected + lines[0][len(first):]
+            return "fix-path", bom + "".join(prefix + lines)
+        return "ok", None
+
+    top = "".join(lines[:30])
+    spdx = [m.group(1) for m in SPDX_RE.finditer(top)]
+    copyrights = [m.group(0) for m in COPYRIGHT_RE.finditer(top)]
+    if (FOREIGN_LICENSE.search(top) or any(s != "LGPL-3.0-only" for s in spdx)
+            or any("MobileGL-Dev" not in line for line in copyrights)):
+        return "foreign", None
+
+    if lines and lines[0].strip() == "%s %s" % (c, OWN_SPDX):
+        lines.pop(0)  # the full header below says the same
+    header = [l + eol for l in HEADER.format(c=c, path=path).rstrip("\n").split("\n")]
+    if lines and lines[0].strip():
+        lines.insert(0, eol)  # one blank line between the header and the code
+    return "add", bom + "".join(prefix + header + lines)
+
+
+def tracked():
+    out = subprocess.run(["git", "-C", ROOT, "-c", "core.quotePath=false", "ls-files"],
+                         stdout=subprocess.PIPE).stdout.decode("utf-8", "replace")
+    return [p for p in out.splitlines() if covered(p)]
+
+
+def main(argv):
+    check = "--check" in argv
+    paths = [os.path.relpath(os.path.abspath(p), ROOT).replace(os.sep, "/") for p in argv if p != "--check"] or tracked()
+    needs = 0
+    for path in paths:
+        if not covered(path):
+            continue
+        try:
+            with open(os.path.join(ROOT, path), encoding="utf-8", newline="") as fh:
+                text = fh.read()
+        except UnicodeDecodeError:
+            print("%s: not UTF-8, skipped" % path)
+            needs += 1
+            continue
+        status, new_text = plan(path, text)
+        if status in QUIET:
+            continue
+        needs += 1
+        if status in MANUAL:
+            print("%s: %s, fix by hand" % (path, status))
+        elif check:
+            print("%s: needs %s" % (path, status))
         else:
-            new_content = new_header + "\n" + content
+            with open(os.path.join(ROOT, path), "w", encoding="utf-8", newline="") as fh:
+                fh.write(new_text)
+            print("%s: %s" % (path, status))
+    print("%d file(s) %s" % (needs, "need attention" if check else "changed or reported"))
+    return 1 if check and needs else 0
 
-        if new_content != content:
-            with open(file_path, "w", encoding="utf-8") as f:
-                f.write(new_content)
-            processed += 1
-            print(f"\n{CYAN}Processing{RESET} {SIMPLE_ARROW} {file_path}\n   {ARROW} {GREEN}{OK}{RESET} Updated")
-        else:
-            skipped += 1
-            print(f"\n{CYAN}Processing{RESET} {SIMPLE_ARROW} {file_path}\n   {ARROW} {GREEN}{OK}{RESET} {YELLOW}No changes{RESET}")
-
-    except Exception as e:
-        print(f"\n{CYAN}Processing{RESET} {SIMPLE_ARROW} {file_path}\n   {ARROW} {RED}{FAIL}{RESET} {e}")
-
-print(f"\n{GREEN}All done!{RESET} Processed: {processed}, Skipped: {skipped}, Total: {total}")
 
+if __name__ == "__main__":
+    sys.exit(main(sys.argv[1:]))