This commit is the first in a series of similar commits to clean up
obsolete `extern crate` statements
Since Rust 1.30, normal macros can be imported via `use`, and with Rust
1.31 and edition 2018 this has become the preferred approach.
`extern crate` is only needed for `alloc` in `no_std` crates, which does
not apply here.
By dropping these (often redundant or odd) `extern crate` lines, we
expose the actual dependencies more clearly and reduce technical debt.
## Auto-generation of the series
Most of this series was produced automatically:
1. Removed all "extern crate" references
2. Run the script [0] to add missing `use` statements
3. Run `cargo +nightly fmt --all`
4. Fix the remaining problems manually
The treewide changes were then split into per-folder commits.
[0]
```python
import os
import re
# Mapping of macro/function usage to imports
MACRO_IMPORTS = {
"info!": "use log::info;\n",
"debug!": "use log::debug;\n",
"error!": "use log::error;\n",
"trace!": "use log::trace;\n",
"warn!": "use log::warn;\n",
"event!": "use event_monitor::event;\n",
"anyhow!(": "use anyhow::anyhow;\n",
"bitflags!(": "use bitflags::bitflags;\n",
"ioctl_ior_nr!": "use vmm_sys_util::{ioctl_ior_nr};\n",
"ioctl_iow_nr!": "use vmm_sys_util::{ioctl_iow_nr};\n",
}
# Regex for finding the first use statement
USE_REGEX = re.compile(r"^\s*(use|pub use) .+?;")
def process_file(path):
with open(path, "r", encoding="utf-8") as f:
lines = f.readlines()
content = "".join(lines)
existing_imports = set(lines)
needed_imports = set()
# Check macros/functions against mapping, only add if not already present
for key, import_stmt in MACRO_IMPORTS.items():
if key in content and import_stmt not in existing_imports:
needed_imports.add(import_stmt)
if not needed_imports:
print(f"Unmodified {path} (no new imports needed)")
return # Nothing to do
# Find first use or pub use statement
for i, line in enumerate(lines):
if USE_REGEX.match(line):
insertion_index = i + 1
break
else:
print(f"Unmodified {path} (no use or pub use statement found)")
return # No use statement found, skip file
# Insert imports
lines[insertion_index:insertion_index] = list(needed_imports)
# Write back file
with open(path, "w", encoding="utf-8") as f:
f.writelines(lines)
print(f"Modified {path}, added imports: {''.join(needed_imports).strip()}")
for root, _, files in os.walk("."):
for file in files:
if file.endswith(".rs"):
process_file(os.path.join(root, file))
```
Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com