Files
codeql/swift/codegen/lib/render.py
Paolo Tranquilli 773ef62406 Swift: added trapgen
This checks in the trapgen script generating trap entries in C++.

The codegen suite has been slightly reorganized, moving the templates
directory up one level and chopping everything into smaller bazel
packages. Running tests is now done via
```
bazel run //swift/codegen/test
```

With respect to the PoC, the nested `codeql::trap` namespace has been
dropped in favour of a `Trap` prefix (or suffix in case of entries)
within the `codeql` namespace. Also, generated C++ code is not checked
in in git any more, and generated during build. Finally, labels get
printed in hex in the trap file.

`TrapLabel` is for the moment only default-constructible, so only one
single label is possible. `TrapArena`, that is responsible for creating
disjoint labels will come in a later commit.
2022-04-28 12:01:59 +02:00

51 lines
1.8 KiB
Python

""" template renderer module, wrapping around `pystache.Renderer`
`pystache` is a python mustache engine, and mustache is a template language. More information on
https://mustache.github.io/
"""
import logging
import pathlib
import pystache
from . import paths
log = logging.getLogger(__name__)
class Renderer:
""" Template renderer using mustache templates in the `templates` directory """
def __init__(self):
self._r = pystache.Renderer(search_dirs=str(paths.templates_dir), escape=lambda u: u)
self.written = set()
def render(self, data, output: pathlib.Path, guard_base: pathlib.Path = None):
""" Render `data` to `output`.
`data` must have a `template` attribute denoting which template to use from the template directory.
If the file is unchanged, then no write is performed (and `done_something` remains unchanged)
If `guard_base` is provided, it must be a path at the root of `output` and a header guard will be injected in
the template based off of the relative path of `output` in `guard_base`
"""
mnemonic = type(data).__name__
output.parent.mkdir(parents=True, exist_ok=True)
guard = None
if guard_base is not None:
guard = str(output.relative_to(guard_base)).replace("/", "_").replace(".", "_").upper()
data = self._r.render_name(data.template, data, generator=paths.exe_file, guard=guard)
with open(output, "w") as out:
out.write(data)
log.debug(f"generated {mnemonic} {output.name}")
self.written.add(output)
def cleanup(self, existing):
""" Remove files in `existing` for which no `render` has been called """
for f in existing - self.written:
f.unlink(missing_ok=True)
log.info(f"removed {f.name}")