diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 00:47:55 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 00:47:55 +0000 |
commit | 26a029d407be480d791972afb5975cf62c9360a6 (patch) | |
tree | f435a8308119effd964b339f76abb83a57c29483 /third_party/rust/diplomat-runtime | |
parent | Initial commit. (diff) | |
download | firefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz firefox-26a029d407be480d791972afb5975cf62c9360a6.zip |
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/diplomat-runtime')
-rw-r--r-- | third_party/rust/diplomat-runtime/.cargo-checksum.json | 1 | ||||
-rw-r--r-- | third_party/rust/diplomat-runtime/Cargo.toml | 36 | ||||
-rw-r--r-- | third_party/rust/diplomat-runtime/LICENSE-APACHE | 201 | ||||
-rw-r--r-- | third_party/rust/diplomat-runtime/LICENSE-MIT | 27 | ||||
-rw-r--r-- | third_party/rust/diplomat-runtime/src/lib.rs | 32 | ||||
-rw-r--r-- | third_party/rust/diplomat-runtime/src/result.rs | 60 | ||||
-rw-r--r-- | third_party/rust/diplomat-runtime/src/wasm_glue.rs | 94 | ||||
-rw-r--r-- | third_party/rust/diplomat-runtime/src/writeable.rs | 189 |
8 files changed, 640 insertions, 0 deletions
diff --git a/third_party/rust/diplomat-runtime/.cargo-checksum.json b/third_party/rust/diplomat-runtime/.cargo-checksum.json new file mode 100644 index 0000000000..fa0aae0776 --- /dev/null +++ b/third_party/rust/diplomat-runtime/.cargo-checksum.json @@ -0,0 +1 @@ +{"files":{"Cargo.toml":"ea77755aae387e62c45564000302e3c7a5ceda3be2f9ef8664e26ee871627b88","LICENSE-APACHE":"639c20c7f14fb122750d5ad1a6cfb116d9bf8d103e709ee40949e5a12a731666","LICENSE-MIT":"3337fe6e4a3830ad87c23cb9d6d750f9a1e5c45efc08de9c76c1a207fc6966c4","src/lib.rs":"1f42457d57ec23fd89f05af631eb73728f37a9790cd604ce1ce94ef153869fb0","src/result.rs":"2b07ce3cbb02a141abc35742f307cc4ef2b097ce610e04d92a50c469f354401d","src/wasm_glue.rs":"3712ccddfeacb98a37be9354a315cc013d9b6ba0bf2f351e0a806112d1f87c15","src/writeable.rs":"80d8a93feba545fcb3150b8daf546f3e060b0c8c11f13917409dd455abe0c3bd"},"package":"f7b0f23d549a46540e26e5490cd44c64ced0d762959f1ffdec6ab0399634cf3c"}
\ No newline at end of file diff --git a/third_party/rust/diplomat-runtime/Cargo.toml b/third_party/rust/diplomat-runtime/Cargo.toml new file mode 100644 index 0000000000..99c0e4c6ed --- /dev/null +++ b/third_party/rust/diplomat-runtime/Cargo.toml @@ -0,0 +1,36 @@ +# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO +# +# When uploading crates to the registry Cargo will automatically +# "normalize" Cargo.toml files for maximal compatibility +# with all versions of Cargo and also rewrite `path` dependencies +# to registry (e.g., crates.io) dependencies. +# +# If you are reading this file be aware that the original Cargo.toml +# will likely look very different (and much more reasonable). +# See Cargo.toml.orig for the original contents. + +[package] +edition = "2018" +name = "diplomat-runtime" +version = "0.7.0" +authors = [ + "Shadaj Laddad <shadaj@users.noreply.github.com>", + "Manish Goregaokar <manishsmail@gmail.com>", + "Quinn Okabayashi <QnnOkabayashi@users.noreply.github.com>", +] +description = "Common runtime utilities used by diplomat codegen" +documentation = "https://docs.rs/diplomat_core/" +keywords = [ + "ffi", + "codegen", +] +categories = ["development-tools"] +license = "MIT OR Apache-2.0" +repository = "https://github.com/rust-diplomat/diplomat" + +[lib] +path = "src/lib.rs" + +[dependencies.log] +version = "0.4" +optional = true diff --git a/third_party/rust/diplomat-runtime/LICENSE-APACHE b/third_party/rust/diplomat-runtime/LICENSE-APACHE new file mode 100644 index 0000000000..05fcffa855 --- /dev/null +++ b/third_party/rust/diplomat-runtime/LICENSE-APACHE @@ -0,0 +1,201 @@ + Apache License + Version 2.0, January 2004 + http://www.apache.org/licenses/ + +TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + +1. Definitions. + + "License" shall mean the terms and conditions for use, reproduction, + and distribution as defined by Sections 1 through 9 of this document. + + "Licensor" shall mean the copyright owner or entity authorized by + the copyright owner that is granting the License. + + "Legal Entity" shall mean the union of the acting entity and all + other entities that control, are controlled by, or are under common + control with that entity. For the purposes of this definition, + "control" means (i) the power, direct or indirect, to cause the + direction or management of such entity, whether by contract or + otherwise, or (ii) ownership of fifty percent (50%) or more of the + outstanding shares, or (iii) beneficial ownership of such entity. + + "You" (or "Your") shall mean an individual or Legal Entity + exercising permissions granted by this License. + + "Source" form shall mean the preferred form for making modifications, + including but not limited to software source code, documentation + source, and configuration files. + + "Object" form shall mean any form resulting from mechanical + transformation or translation of a Source form, including but + not limited to compiled object code, generated documentation, + and conversions to other media types. + + "Work" shall mean the work of authorship, whether in Source or + Object form, made available under the License, as indicated by a + copyright notice that is included in or attached to the work + (an example is provided in the Appendix below). + + "Derivative Works" shall mean any work, whether in Source or Object + form, that is based on (or derived from) the Work and for which the + editorial revisions, annotations, elaborations, or other modifications + represent, as a whole, an original work of authorship. For the purposes + of this License, Derivative Works shall not include works that remain + separable from, or merely link (or bind by name) to the interfaces of, + the Work and Derivative Works thereof. + + "Contribution" shall mean any work of authorship, including + the original version of the Work and any modifications or additions + to that Work or Derivative Works thereof, that is intentionally + submitted to Licensor for inclusion in the Work by the copyright owner + or by an individual or Legal Entity authorized to submit on behalf of + the copyright owner. For the purposes of this definition, "submitted" + means any form of electronic, verbal, or written communication sent + to the Licensor or its representatives, including but not limited to + communication on electronic mailing lists, source code control systems, + and issue tracking systems that are managed by, or on behalf of, the + Licensor for the purpose of discussing and improving the Work, but + excluding communication that is conspicuously marked or otherwise + designated in writing by the copyright owner as "Not a Contribution." + + "Contributor" shall mean Licensor and any individual or Legal Entity + on behalf of whom a Contribution has been received by Licensor and + subsequently incorporated within the Work. + +2. Grant of Copyright License. Subject to the terms and conditions of + this License, each Contributor hereby grants to You a perpetual, + worldwide, non-exclusive, no-charge, royalty-free, irrevocable + copyright license to reproduce, prepare Derivative Works of, + publicly display, publicly perform, sublicense, and distribute the + Work and such Derivative Works in Source or Object form. + +3. Grant of Patent License. Subject to the terms and conditions of + this License, each Contributor hereby grants to You a perpetual, + worldwide, non-exclusive, no-charge, royalty-free, irrevocable + (except as stated in this section) patent license to make, have made, + use, offer to sell, sell, import, and otherwise transfer the Work, + where such license applies only to those patent claims licensable + by such Contributor that are necessarily infringed by their + Contribution(s) alone or by combination of their Contribution(s) + with the Work to which such Contribution(s) was submitted. If You + institute patent litigation against any entity (including a + cross-claim or counterclaim in a lawsuit) alleging that the Work + or a Contribution incorporated within the Work constitutes direct + or contributory patent infringement, then any patent licenses + granted to You under this License for that Work shall terminate + as of the date such litigation is filed. + +4. Redistribution. You may reproduce and distribute copies of the + Work or Derivative Works thereof in any medium, with or without + modifications, and in Source or Object form, provided that You + meet the following conditions: + + (a) You must give any other recipients of the Work or + Derivative Works a copy of this License; and + + (b) You must cause any modified files to carry prominent notices + stating that You changed the files; and + + (c) You must retain, in the Source form of any Derivative Works + that You distribute, all copyright, patent, trademark, and + attribution notices from the Source form of the Work, + excluding those notices that do not pertain to any part of + the Derivative Works; and + + (d) If the Work includes a "NOTICE" text file as part of its + distribution, then any Derivative Works that You distribute must + include a readable copy of the attribution notices contained + within such NOTICE file, excluding those notices that do not + pertain to any part of the Derivative Works, in at least one + of the following places: within a NOTICE text file distributed + as part of the Derivative Works; within the Source form or + documentation, if provided along with the Derivative Works; or, + within a display generated by the Derivative Works, if and + wherever such third-party notices normally appear. The contents + of the NOTICE file are for informational purposes only and + do not modify the License. You may add Your own attribution + notices within Derivative Works that You distribute, alongside + or as an addendum to the NOTICE text from the Work, provided + that such additional attribution notices cannot be construed + as modifying the License. + + You may add Your own copyright statement to Your modifications and + may provide additional or different license terms and conditions + for use, reproduction, or distribution of Your modifications, or + for any such Derivative Works as a whole, provided Your use, + reproduction, and distribution of the Work otherwise complies with + the conditions stated in this License. + +5. Submission of Contributions. Unless You explicitly state otherwise, + any Contribution intentionally submitted for inclusion in the Work + by You to the Licensor shall be under the terms and conditions of + this License, without any additional terms or conditions. + Notwithstanding the above, nothing herein shall supersede or modify + the terms of any separate license agreement you may have executed + with Licensor regarding such Contributions. + +6. Trademarks. This License does not grant permission to use the trade + names, trademarks, service marks, or product names of the Licensor, + except as required for reasonable and customary use in describing the + origin of the Work and reproducing the content of the NOTICE file. + +7. Disclaimer of Warranty. Unless required by applicable law or + agreed to in writing, Licensor provides the Work (and each + Contributor provides its Contributions) on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or + implied, including, without limitation, any warranties or conditions + of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A + PARTICULAR PURPOSE. You are solely responsible for determining the + appropriateness of using or redistributing the Work and assume any + risks associated with Your exercise of permissions under this License. + +8. Limitation of Liability. In no event and under no legal theory, + whether in tort (including negligence), contract, or otherwise, + unless required by applicable law (such as deliberate and grossly + negligent acts) or agreed to in writing, shall any Contributor be + liable to You for damages, including any direct, indirect, special, + incidental, or consequential damages of any character arising as a + result of this License or out of the use or inability to use the + Work (including but not limited to damages for loss of goodwill, + work stoppage, computer failure or malfunction, or any and all + other commercial damages or losses), even if such Contributor + has been advised of the possibility of such damages. + +9. Accepting Warranty or Additional Liability. While redistributing + the Work or Derivative Works thereof, You may choose to offer, + and charge a fee for, acceptance of support, warranty, indemnity, + or other liability obligations and/or rights consistent with this + License. However, in accepting such obligations, You may act only + on Your own behalf and on Your sole responsibility, not on behalf + of any other Contributor, and only if You agree to indemnify, + defend, and hold each Contributor harmless for any liability + incurred by, or claims asserted against, such Contributor by reason + of your accepting any such warranty or additional liability. + +END OF TERMS AND CONDITIONS + +APPENDIX: How to apply the Apache License to your work. + + To apply the Apache License to your work, attach the following + boilerplate notice, with the fields enclosed by brackets "[]" + replaced with your own identifying information. (Don't include + the brackets!) The text should be enclosed in the appropriate + comment syntax for the file format. We also recommend that a + file or class name and description of purpose be included on the + same "printed page" as the copyright notice for easier + identification within third-party archives. + +Copyright 2022 The Diplomat Developers + +Licensed under the Apache License, Version 2.0 (the "License"); +you may not use this file except in compliance with the License. +You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software +distributed under the License is distributed on an "AS IS" BASIS, +WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +See the License for the specific language governing permissions and +limitations under the License. diff --git a/third_party/rust/diplomat-runtime/LICENSE-MIT b/third_party/rust/diplomat-runtime/LICENSE-MIT new file mode 100644 index 0000000000..cf62c31bc7 --- /dev/null +++ b/third_party/rust/diplomat-runtime/LICENSE-MIT @@ -0,0 +1,27 @@ +MIT License + +Copyright (c) 2022 The Diplomat Developers + +Permission is hereby granted, free of charge, to any +person obtaining a copy of this software and associated +documentation files (the "Software"), to deal in the +Software without restriction, including without +limitation the rights to use, copy, modify, merge, +publish, distribute, sublicense, and/or sell copies of +the Software, and to permit persons to whom the Software +is furnished to do so, subject to the following +conditions: + +The above copyright notice and this permission notice +shall be included in all copies or substantial portions +of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF +ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED +TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A +PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT +SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY +CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION +OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR +IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER +DEALINGS IN THE SOFTWARE. diff --git a/third_party/rust/diplomat-runtime/src/lib.rs b/third_party/rust/diplomat-runtime/src/lib.rs new file mode 100644 index 0000000000..fa1c5d7dda --- /dev/null +++ b/third_party/rust/diplomat-runtime/src/lib.rs @@ -0,0 +1,32 @@ +#![cfg_attr(not(any(target_arch = "wasm32")), no_std)] + +extern crate alloc; + +use alloc::alloc::Layout; + +#[cfg(target_arch = "wasm32")] +// defines `extern "C" diplomat_init()` +mod wasm_glue; + +mod writeable; +pub use writeable::DiplomatWriteable; + +mod result; +pub use result::DiplomatResult; + +/// Allocates a buffer of a given size in Rust's memory. +/// +/// # Safety +/// - The allocated buffer must be freed with [`diplomat_free()`]. +#[no_mangle] +pub unsafe extern "C" fn diplomat_alloc(size: usize, align: usize) -> *mut u8 { + alloc::alloc::alloc(Layout::from_size_align(size, align).unwrap()) +} + +/// Frees a buffer that was allocated in Rust's memory. +/// # Safety +/// - `ptr` must be a pointer to a valid buffer allocated by [`diplomat_alloc()`]. +#[no_mangle] +pub unsafe extern "C" fn diplomat_free(ptr: *mut u8, size: usize, align: usize) { + alloc::alloc::dealloc(ptr, Layout::from_size_align(size, align).unwrap()) +} diff --git a/third_party/rust/diplomat-runtime/src/result.rs b/third_party/rust/diplomat-runtime/src/result.rs new file mode 100644 index 0000000000..003281fd43 --- /dev/null +++ b/third_party/rust/diplomat-runtime/src/result.rs @@ -0,0 +1,60 @@ +use core::mem::ManuallyDrop; + +#[repr(C)] +union DiplomatResultValue<T, E> { + ok: ManuallyDrop<T>, + err: ManuallyDrop<E>, +} + +/// A `Result`-like type that can be passed across the FFI boundary +/// as a value. Use this type when returning a result from an FFI +/// function instead of `Result`. +#[repr(C)] +pub struct DiplomatResult<T, E> { + value: DiplomatResultValue<T, E>, + pub is_ok: bool, +} + +impl<T, E> Drop for DiplomatResult<T, E> { + fn drop(&mut self) { + unsafe { + if self.is_ok { + let _ = ManuallyDrop::take(&mut self.value.ok); + } else { + let _ = ManuallyDrop::take(&mut self.value.err); + } + } + } +} + +impl<T, E> From<Result<T, E>> for DiplomatResult<T, E> { + fn from(result: Result<T, E>) -> Self { + match result { + Result::Ok(ok) => DiplomatResult { + value: DiplomatResultValue { + ok: ManuallyDrop::new(ok), + }, + is_ok: true, + }, + + Result::Err(err) => DiplomatResult { + value: DiplomatResultValue { + err: ManuallyDrop::new(err), + }, + is_ok: false, + }, + } + } +} + +impl<T, E> From<DiplomatResult<T, E>> for Result<T, E> { + fn from(mut result: DiplomatResult<T, E>) -> Result<T, E> { + unsafe { + if result.is_ok { + Ok(ManuallyDrop::take(&mut result.value.ok)) + } else { + Err(ManuallyDrop::take(&mut result.value.err)) + } + } + } +} diff --git a/third_party/rust/diplomat-runtime/src/wasm_glue.rs b/third_party/rust/diplomat-runtime/src/wasm_glue.rs new file mode 100644 index 0000000000..98a46139a3 --- /dev/null +++ b/third_party/rust/diplomat-runtime/src/wasm_glue.rs @@ -0,0 +1,94 @@ +use alloc::format; +use core::panic::PanicInfo; + +#[no_mangle] +unsafe extern "C" fn diplomat_init() { + #[cfg(debug_assertions)] + std::panic::set_hook(Box::new(panic_handler)); + #[cfg(feature = "log")] + log::set_logger(&ConsoleLogger) + .map(|()| log::set_max_level(log::LevelFilter::Debug)) + .unwrap(); +} + +fn panic_handler(info: &PanicInfo) { + let msg = match info.payload().downcast_ref::<&'static str>() { + Some(&s) => s, + None => match info.payload().downcast_ref::<String>() { + Some(s) => s.as_str(), + None => "Box<Any>", + }, + }; + + let msg = match info.location() { + Some(l) => format!( + "wasm panicked at {}:{}:{}:\n{msg}", + l.file(), + l.line(), + l.column(), + ), + None => format!("wasm panicked at <unknown location>:\n{msg}"), + }; + + extern "C" { + fn diplomat_throw_error_js(ptr: *const u8, len: usize); + } + + unsafe { diplomat_throw_error_js(msg.as_ptr(), msg.len()) } +} + +#[cfg(feature = "log")] +struct ConsoleLogger; + +#[cfg(feature = "log")] +impl log::Log for ConsoleLogger { + #[inline] + fn enabled(&self, metadata: &log::Metadata) -> bool { + metadata.level() <= log::max_level() + } + + fn log(&self, record: &log::Record) { + if !self.enabled(record.metadata()) { + return; + } + + let out = match record.level() { + log::Level::Error => { + extern "C" { + fn diplomat_console_error_js(ptr: *const u8, len: usize); + } + diplomat_console_error_js + } + log::Level::Warn => { + extern "C" { + fn diplomat_console_warn_js(ptr: *const u8, len: usize); + } + diplomat_console_warn_js + } + log::Level::Info => { + extern "C" { + fn diplomat_console_info_js(ptr: *const u8, len: usize); + } + diplomat_console_info_js + } + log::Level::Debug => { + extern "C" { + fn diplomat_console_log_js(ptr: *const u8, len: usize); + } + diplomat_console_log_js + } + log::Level::Trace => { + extern "C" { + fn diplomat_console_debug_js(ptr: *const u8, len: usize); + } + diplomat_console_debug_js + } + }; + + let msg = alloc::format!("{}", record.args()); + + unsafe { out(msg.as_ptr(), msg.len()) }; + } + + fn flush(&self) {} +} diff --git a/third_party/rust/diplomat-runtime/src/writeable.rs b/third_party/rust/diplomat-runtime/src/writeable.rs new file mode 100644 index 0000000000..d37f4197b5 --- /dev/null +++ b/third_party/rust/diplomat-runtime/src/writeable.rs @@ -0,0 +1,189 @@ +use alloc::boxed::Box; +use alloc::vec::Vec; +use core::ffi::c_void; +use core::{fmt, ptr}; + +/// An object that can one can write UTF-8 strings to +/// +/// This allows the C API to write to arbitrary kinds of objects, for example a +/// C++ std::string or a char buffer. +/// +/// The way to use this object is to fill out the `buf`, `len`, `cap` fields with +/// appropriate values for the buffer, its current length, and its current capacity, +/// and `flush` and `grow` with appropriate callbacks (using `context` to reference any +/// state they need). This object will be passed by mutable reference to the Rust side, +/// and Rust will write to it, calling `grow()` as necessary. Once done, it will call `flush()` +/// to update any state on `context` (e.g. adding a null terminator, updating the length). +/// The object on the foreign side will be directly usable after this, the foreign side +/// need not perform additional state updates after passing an [`DiplomatWriteable`] to +/// a function. +/// +/// [`diplomat_simple_writeable()`] can be used to write to a fixed-size char buffer. +/// +/// May be extended in the future to support further invariants +/// +/// DiplomatWriteable will not perform any cleanup on `context` or `buf`, these are logically +/// "borrows" from the FFI side. +/// +/// # Safety invariants: +/// - `flush()` and `grow()` will be passed `self` including `context` and it should always be safe to do so. +/// `context` may be null, however `flush()` and `grow()` must then be ready to receive it as such. +/// - `buf` must be `cap` bytes long +/// - `grow()` must either return false or update `buf` and `cap` for a valid buffer +/// of at least the requested buffer size +/// - `DiplomatWriteable::flush()` will be automatically called by Diplomat. `flush()` might also be called +/// (erroneously) on the Rust side (it's a public method), so it must be idempotent. +#[repr(C)] +pub struct DiplomatWriteable { + /// Context pointer for additional data needed by `grow()` and `flush()`. May be `null`. + /// + /// The pointer may reference structured data on the foreign side, + /// such as C++ std::string, used to reallocate buf. + context: *mut c_void, + /// The raw string buffer, which will be mutated on the Rust side. + buf: *mut u8, + /// The current filled size of the buffer + len: usize, + /// The current capacity of the buffer + cap: usize, + /// Called by Rust to indicate that there is no more data to write. + /// + /// May be called multiple times. + /// + /// Arguments: + /// - `self` (`*mut DiplomatWriteable`): This `DiplomatWriteable` + flush: extern "C" fn(*mut DiplomatWriteable), + /// Called by Rust to request more capacity in the buffer. The implementation should allocate a new + /// buffer and copy the contents of the old buffer into the new buffer, updating `self.buf` and `self.cap` + /// + /// Arguments: + /// - `self` (`*mut DiplomatWriteable`): This `DiplomatWriteable` + /// - `capacity` (`usize`): The requested capacity. + /// + /// Returns: `true` if the allocation succeeded. Should not update any state if it failed. + grow: extern "C" fn(*mut DiplomatWriteable, usize) -> bool, +} + +impl DiplomatWriteable { + /// Call this function before releasing the buffer to C + pub fn flush(&mut self) { + (self.flush)(self); + } +} +impl fmt::Write for DiplomatWriteable { + fn write_str(&mut self, s: &str) -> Result<(), fmt::Error> { + let needed_len = self.len + s.len(); + if needed_len > self.cap { + let success = (self.grow)(self, needed_len); + if !success { + return Err(fmt::Error); + } + } + debug_assert!(needed_len <= self.cap); + unsafe { + ptr::copy_nonoverlapping(s.as_bytes().as_ptr(), self.buf.add(self.len), s.len()); + } + self.len = needed_len; + Ok(()) + } +} + +/// Create an `DiplomatWriteable` that can write to a fixed-length stack allocated `u8` buffer. +/// +/// Once done, this will append a null terminator to the written string. +/// +/// # Safety +/// +/// - `buf` must be a valid pointer to a region of memory that can hold at `buf_size` bytes +#[no_mangle] +pub unsafe extern "C" fn diplomat_simple_writeable( + buf: *mut u8, + buf_size: usize, +) -> DiplomatWriteable { + extern "C" fn grow(_this: *mut DiplomatWriteable, _cap: usize) -> bool { + false + } + extern "C" fn flush(this: *mut DiplomatWriteable) { + unsafe { + debug_assert!((*this).len <= (*this).cap); + let buf = (*this).buf; + ptr::write(buf.add((*this).len), 0) + } + } + DiplomatWriteable { + context: ptr::null_mut(), + buf, + len: 0, + // keep an extra byte in our pocket for the null terminator + cap: buf_size - 1, + flush, + grow, + } +} + +/// Create an [`DiplomatWriteable`] that can write to a dynamically allocated buffer managed by Rust. +/// +/// Use [`diplomat_buffer_writeable_destroy()`] to free the writable and its underlying buffer. +#[no_mangle] +pub extern "C" fn diplomat_buffer_writeable_create(cap: usize) -> *mut DiplomatWriteable { + extern "C" fn grow(this: *mut DiplomatWriteable, new_cap: usize) -> bool { + unsafe { + let this = this.as_mut().unwrap(); + let mut vec = Vec::from_raw_parts(this.buf, 0, this.cap); + vec.reserve(new_cap); + this.cap = vec.capacity(); + this.buf = vec.as_mut_ptr(); + core::mem::forget(vec); + } + true + } + + extern "C" fn flush(_: *mut DiplomatWriteable) {} + + let mut vec = Vec::<u8>::with_capacity(cap); + let ret = DiplomatWriteable { + context: ptr::null_mut(), + buf: vec.as_mut_ptr(), + len: 0, + cap, + flush, + grow, + }; + + core::mem::forget(vec); + Box::into_raw(Box::new(ret)) +} + +/// Grabs a pointer to the underlying buffer of a writable. +/// +/// # Safety +/// - The returned pointer is valid until the passed writable is destroyed. +/// - `this` must be a pointer to a valid [`DiplomatWriteable`] constructed by +/// [`diplomat_buffer_writeable_create()`]. +#[no_mangle] +pub extern "C" fn diplomat_buffer_writeable_get_bytes(this: &DiplomatWriteable) -> *mut u8 { + this.buf +} + +/// Gets the length in bytes of the content written to the writable. +/// +/// # Safety +/// - `this` must be a pointer to a valid [`DiplomatWriteable`] constructed by +/// [`diplomat_buffer_writeable_create()`]. +#[no_mangle] +pub extern "C" fn diplomat_buffer_writeable_len(this: &DiplomatWriteable) -> usize { + this.len +} + +/// Destructor for Rust-memory backed writables. +/// +/// # Safety +/// - `this` must be a pointer to a valid [`DiplomatWriteable`] constructed by +/// [`diplomat_buffer_writeable_create()`]. +#[no_mangle] +pub unsafe extern "C" fn diplomat_buffer_writeable_destroy(this: *mut DiplomatWriteable) { + let this = Box::from_raw(this); + let vec = Vec::from_raw_parts(this.buf, 0, this.cap); + drop(vec); + drop(this); +} |