Struct Source

pub struct Source { /* private fields */ }

Provides access to prebindgen data generated by the #[prebindgen] macro

The Source struct reads prebindgen data files from a directory that was initialized by init_prebindgen_out_dir in the source project’s build.rs. This allows destination projects to access and process the collected FFI interface definitions.

Workflow

1. Source project: Calls init_prebindgen_out_dir() in build.rs and uses #[prebindgen] macro
2. Destination project: Uses Source::new() to read the collected data

Groups

Items are organized into groups based on the first parameter of the #[prebindgen] macro. For example, #[prebindgen("structs")] creates items in the “structs” group. Items without an explicit group are placed in the “default” group.

Example

The PREBINDGEN_OUT_DIR constant is defined in the source FFI crate using the prebindgen_out_dir!() macro:

// In source_ffi/src/lib.rs
use prebindgen_proc_macro::{prebindgen, prebindgen_out_dir};
 
pub const PREBINDGEN_OUT_DIR: &str = prebindgen_out_dir!();
 
#[prebindgen]
pub fn my_function() -> i32 { 42 }

Then in the destination project’s build.rs:

let source = prebindgen::Source::new(source_ffi::PREBINDGEN_OUT_DIR);
 
// Process all items
for (item, location) in source.items_all() {
    // Process each syn::Item...
}

Implementations

impl Source

pub fn new<P: AsRef<Path>>(input_dir: P) -> Self

Parameters:

• input_dir: Path to the directory containing prebindgen data files

pub fn crate_name(&self) -> &str

Returns the name of the source crate that generated the prebindgen data

This is typically used by FfiConverter to generate proper function calls to the original crate.

Example

let source = prebindgen::Source::new(source_ffi::PREBINDGEN_OUT_DIR);
let crate_name = source.crate_name();

pub fn items_in_groups( &self, groups: &[&str], ) -> impl Iterator<Item = (Item, SourceLocation)>

Returns an iterator over items from specific groups

Parameters

• groups - Array of group names to include

Example

let source = prebindgen::Source::new(source_ffi::PREBINDGEN_OUT_DIR);
// Process only items from "structs" and "functions" groups
let items = source.items_in_groups(&["structs"]).collect::<Vec<_>>();
assert_eq!(items.len(), 1); // only TestStruct should be present

pub fn items_except_groups( &self, groups: &[&str], ) -> impl Iterator<Item = (Item, SourceLocation)>

Returns an iterator over items excluding specific groups

Parameters

• groups - Array of group names to exclude

Example

let source = prebindgen::Source::new(source_ffi::PREBINDGEN_OUT_DIR);
let items = source.items_except_groups(&["structs"]).collect::<Vec<_>>();
assert_eq!(items.len(), 1); // only test_function should be present

pub fn items_all(&self) -> impl Iterator<Item = (Item, SourceLocation)>

Returns an iterator over all items from all groups

This is the most commonly used method for processing all prebindgen items.

Example

let source = prebindgen::Source::new(source_ffi::PREBINDGEN_OUT_DIR);
let items: Vec<_> = source.items_all().collect();
assert_eq!(items.len(), 2); // should contain TestStruct and test_function