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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
/// Alternative implementation for the `generate` command, that we plan to eventually replace the current default with.
///
/// Traditionally, users would invoke `uniffi-bindgen generate` to generate bindings for a single crate, passing it the UDL file, config file, etc.
///
/// library_mode is a new way to generate bindings for multiple crates at once.
/// Users pass the path to the build cdylib file and UniFFI figures everything out, leveraging `cargo_metadata`, the metadata UniFFI stores inside exported symbols in the dylib, etc.
///
/// This brings several advantages.:
/// - No more need to specify the dylib in the `uniffi.toml` file(s)
/// - UniFFI can figure out the dependencies based on the dylib exports and generate the sources for
/// all of them at once.
/// - UniFFI can figure out the package/module names for each crate, eliminating the external
/// package maps.
use crate::{
macro_metadata, overridden_config_value, BindgenCrateConfigSupplier, BindingGenerator,
Component, ComponentInterface, GenerationSettings, Result,
};
use anyhow::bail;
use camino::Utf8Path;
use std::{collections::HashMap, fs};
use toml::value::Table as TomlTable;
use uniffi_meta::{
create_metadata_groups, fixup_external_type, group_metadata, Metadata, MetadataGroup,
};
/// Generate foreign bindings
///
/// This replicates the current process used for generating the builtin bindings.
/// External bindings authors should consider using [find_components], which provides a simpler
/// interface and allows for more flexibility in how the external bindings are generated.
///
/// Returns the list of sources used to generate the bindings, in no particular order.
pub fn generate_bindings<T: BindingGenerator + ?Sized>(
library_path: &Utf8Path,
crate_name: Option<String>,
binding_generator: &T,
config_supplier: &dyn BindgenCrateConfigSupplier,
config_file_override: Option<&Utf8Path>,
out_dir: &Utf8Path,
try_format_code: bool,
) -> Result<Vec<Component<T::Config>>> {
let mut components = find_components(library_path, config_supplier)?
.into_iter()
.map(|Component { ci, config }| {
let toml_value = overridden_config_value(config, config_file_override)?;
let config = binding_generator.new_config(&toml_value)?;
Ok(Component { ci, config })
})
.collect::<Result<Vec<_>>>()?;
let settings = GenerationSettings {
out_dir: out_dir.to_owned(),
try_format_code,
cdylib: calc_cdylib_name(library_path).map(ToOwned::to_owned),
};
binding_generator.update_component_configs(&settings, &mut components)?;
fs::create_dir_all(out_dir)?;
if let Some(crate_name) = &crate_name {
let old_elements = components.drain(..);
let mut matches: Vec<_> = old_elements
.filter(|s| s.ci.crate_name() == crate_name)
.collect();
match matches.len() {
0 => bail!("Crate {crate_name} not found in {library_path}"),
1 => components.push(matches.pop().unwrap()),
n => bail!("{n} crates named {crate_name} found in {library_path}"),
}
}
binding_generator.write_bindings(&settings, &components)?;
Ok(components)
}
// If `library_path` is a C dynamic library, return its name
pub fn calc_cdylib_name(library_path: &Utf8Path) -> Option<&str> {
let cdylib_extensions = [".so", ".dll", ".dylib"];
let filename = library_path.file_name()?;
let filename = filename.strip_prefix("lib").unwrap_or(filename);
for ext in cdylib_extensions {
if let Some(f) = filename.strip_suffix(ext) {
return Some(f);
}
}
None
}
/// Find UniFFI components from a shared library file
///
/// This method inspects the library file and creates [ComponentInterface] instances for each
/// component used to build it. It parses the UDL files from `uniffi::include_scaffolding!` macro
/// calls.
///
/// `config_supplier` is used to find UDL files on disk and load config data.
pub fn find_components(
library_path: &Utf8Path,
config_supplier: &dyn BindgenCrateConfigSupplier,
) -> Result<Vec<Component<TomlTable>>> {
let items = macro_metadata::extract_from_library(library_path)?;
let mut metadata_groups = create_metadata_groups(&items);
group_metadata(&mut metadata_groups, items)?;
// Collect and process all UDL from all groups at the start - the fixups
// of external types makes this tricky to do as we finalize the group.
let mut udl_items: HashMap<String, MetadataGroup> = HashMap::new();
for group in metadata_groups.values() {
let crate_name = group.namespace.crate_name.clone();
if let Some(mut metadata_group) = load_udl_metadata(group, &crate_name, config_supplier)? {
// fixup the items.
metadata_group.items = metadata_group
.items
.into_iter()
.map(|item| fixup_external_type(item, &metadata_groups))
// some items are both in UDL and library metadata. For many that's fine but
// uniffi-traits aren't trivial to compare meaning we end up with dupes.
// We filter out such problematic items here.
.filter(|item| !matches!(item, Metadata::UniffiTrait { .. }))
.collect();
udl_items.insert(crate_name, metadata_group);
};
}
metadata_groups
.into_values()
.map(|group| {
let crate_name = &group.namespace.crate_name;
let mut ci = ComponentInterface::new(crate_name);
if let Some(metadata) = udl_items.remove(crate_name) {
ci.add_metadata(metadata)?;
};
ci.add_metadata(group)?;
let config = config_supplier
.get_toml(ci.crate_name())?
.unwrap_or_default();
Ok(Component { ci, config })
})
.collect()
}
fn load_udl_metadata(
group: &MetadataGroup,
crate_name: &str,
config_supplier: &dyn BindgenCrateConfigSupplier,
) -> Result<Option<MetadataGroup>> {
let udl_items = group
.items
.iter()
.filter_map(|i| match i {
uniffi_meta::Metadata::UdlFile(meta) => Some(meta),
_ => None,
})
.collect::<Vec<_>>();
// We only support 1 UDL file per crate, for no good reason!
match udl_items.len() {
0 => Ok(None),
1 => {
if udl_items[0].module_path != crate_name {
bail!(
"UDL is for crate '{}' but this crate name is '{}'",
udl_items[0].module_path,
crate_name
);
}
let udl = config_supplier.get_udl(crate_name, &udl_items[0].file_stub)?;
let udl_group = uniffi_udl::parse_udl(&udl, crate_name)?;
Ok(Some(udl_group))
}
n => bail!("{n} UDL files found for {crate_name}"),
}
}
#[cfg(test)]
mod test {
use super::*;
#[test]
fn calc_cdylib_name_is_correct() {
assert_eq!(
"uniffi",
calc_cdylib_name("/path/to/libuniffi.so".into()).unwrap()
);
assert_eq!(
"uniffi",
calc_cdylib_name("/path/to/libuniffi.dylib".into()).unwrap()
);
assert_eq!(
"uniffi",
calc_cdylib_name("/path/to/uniffi.dll".into()).unwrap()
);
}
/// Right now we unconditionally strip the `lib` prefix.
///
/// Technically Windows DLLs do not start with a `lib` prefix,
/// but a library name could start with a `lib` prefix.
/// On Linux/macOS this would result in a `liblibuniffi.{so,dylib}` file.
#[test]
#[ignore] // Currently fails.
fn calc_cdylib_name_is_correct_on_windows() {
assert_eq!(
"libuniffi",
calc_cdylib_name("/path/to/libuniffi.dll".into()).unwrap()
);
}
}