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/**
* \mainpage Wasmtime C API
*
* This documentation is an overview and API reference for the C API of
* Wasmtime. The C API is spread between three different header files:
*
* * \ref wasmtime.h
* * \ref wasi.h
* * \ref wasm.h
*
* The \ref wasmtime.h header file includes all the other header files and is
* the main header file you'll likely be using. The \ref wasm.h header file
* comes directly from the
* [WebAssembly/wasm-c-api](https://github.com/WebAssembly/wasm-c-api)
* repository, and at this time the upstream header file does not have
* documentation so Wasmtime provides documentation here. It should be noted
* some semantics may be Wasmtime-specific and may not be portable to other
* engines.
*
* ## Installing the C API
*
* To install the C API from precompiled binaries you can download the
* appropriate binary from the [releases page of
* Wasmtime](https://github.com/bytecodealliance/wasmtime/releases). Artifacts
* for the C API all end in "-c-api" for the filename.
*
* Each archive contains an `include` directory with necessary headers, as well
* as a `lib` directory with both a static archive and a dynamic library of
* Wasmtime. You can link to either of them as you see fit.
*
* ## Installing the C API through CMake
*
* CMake can be used to make the process of linking and compiling easier. An
* example of this if you have wasmtime as a git submodule at
* `third_party/wasmtime`:
* ```
* add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/third_party/wasmtime/crates/c-api
* ${CMAKE_CURRENT_BINARY_DIR}/wasmtime)
* ...
* target_include_directories(YourProject PUBLIC wasmtime)
* target_link_libraries(YourProject PUBLIC wasmtime)
* ```
* `BUILD_SHARED_LIBS` is provided as a define if you would like to build a
* shared library instead. You must distribute the appropriate shared library
* for your platform if you do this.
*
* ## Linking against the C API
*
* You'll want to arrange the `include` directory of the C API to be in your
* compiler's header path (e.g. the `-I` flag). If you're compiling for Windows
* and you're using the static library then you'll also need to pass
* `-DWASM_API_EXTERN=` and `-DWASI_API_EXTERN=` to disable dllimport.
*
* Your final artifact can then be linked with `-lwasmtime`. If you're linking
* against the static library you may need to pass other system libraries
* depending on your platform:
*
* * Linux - `-lpthread -ldl -lm`
* * macOS - no extra flags needed
* * Windows - `ws2_32.lib advapi32.lib userenv.lib ntdll.lib shell32.lib
* ole32.lib bcrypt.lib`
*
* ## Building from Source
*
* The C API is located in the
* [`crates/c-api`](https://github.com/bytecodealliance/wasmtime/tree/main/crates/c-api)
* directory of the [Wasmtime
* repository](https://github.com/bytecodealliance/wasmtime). To build from
* source you'll need a Rust compiler and a checkout of the `wasmtime` project.
* Afterwards you can execute:
*
* ```
* $ cargo build --release -p wasmtime-c-api
* ```
*
* This will place the final artifacts in `target/release`, with names depending
* on what platform you're compiling for.
*
* ## Other resources
*
* Some other handy resources you might find useful when exploring the C API
* documentation are:
*
* * [Rust `wasmtime` crate
* documentation](https://bytecodealliance.github.io/wasmtime/api/wasmtime/) -
* although this documentation is for Rust and not C, you'll find that many
* functions mirror one another and there may be extra documentation in Rust
* you find helpful. If you find yourself having to frequently do this,
* though, please feel free to [file an
* issue](https://github.com/bytecodealliance/wasmtime/issues/new).
*
* * [C embedding
* examples](https://bytecodealliance.github.io/wasmtime/lang-c.html)
* are available online and are tested from the Wasmtime repository itself.
*
* * [Contribution documentation for
* Wasmtime](https://bytecodealliance.github.io/wasmtime/contributing.html) in
* case you're interested in helping out!
*/
/**
* \file wasmtime.h
*
* \brief Wasmtime's C API
*
* This file is the central inclusion point for Wasmtime's C API. There are a
* number of sub-header files but this file includes them all. The C API is
* based on \ref wasm.h but there are many Wasmtime-specific APIs which are
* tailored to Wasmtime's implementation.
*
* The #wasm_config_t and #wasm_engine_t types are used from \ref wasm.h.
* Additionally all type-level information (like #wasm_functype_t) is also
* used from \ref wasm.h. Otherwise, though, all wasm objects (like
* #wasmtime_store_t or #wasmtime_func_t) are used from this header file.
*
* ### Thread Safety
*
* The multithreading story of the C API very closely follows the
* multithreading story of the Rust API for Wasmtime. All objects are safe to
* send to other threads so long as user-specific data is also safe to send to
* other threads. Functions are safe to call from any thread but some functions
* cannot be called concurrently. For example, functions which correspond to
* `&T` in Rust can be called concurrently with any other methods that take
* `&T`. Functions that take `&mut T` in Rust, however, cannot be called
* concurrently with any other function (but can still be invoked on any
* thread).
*
* This generally equates to mutation of internal state. Functions which don't
* mutate anything, such as learning type information through
* #wasmtime_func_type, can be called concurrently. Functions which do require
* mutation, for example #wasmtime_func_call, cannot be called concurrently.
* This is conveyed in the C API with either `const wasmtime_context_t*`
* (concurrency is ok as it's read-only) or `wasmtime_context_t*` (concurrency
* is not ok, mutation may happen).
*
* When in doubt assume that functions cannot be called concurrently with
* aliasing objects.
*
* ### Aliasing
*
* The C API for Wasmtime is intended to be a relatively thin layer over the
* Rust API for Wasmtime. Rust has much more strict rules about aliasing than C
* does, and the Rust API for Wasmtime is designed around these rules to be
* used safely. These same rules must be upheld when using the C API of
* Wasmtime.
*
* The main consequence of this is that the #wasmtime_context_t pointer into
* the #wasmtime_store_t must be carefully used. Since the context is an
* internal pointer into the store it must be used carefully to ensure you're
* not doing something that Rust would otherwise forbid at compile time. A
* #wasmtime_context_t can only be used when you would otherwise have been
* provided access to it. For example in a host function created with
* #wasmtime_func_new you can use #wasmtime_context_t in the host function
* callback. This is because an argument, a #wasmtime_caller_t, provides access
* to #wasmtime_context_t.
*
* ### Stores
*
* A foundational construct in this API is the #wasmtime_store_t. A store is a
* collection of host-provided objects and instantiated wasm modules. Stores are
* often treated as a "single unit" and items within a store are all allowed to
* reference one another. References across stores cannot currently be created.
* For example you cannot pass a function from one store into another store.
*
* A store is not intended to be a global long-lived object. Stores provide no
* means of internal garbage collections of wasm objects (such as instances),
* meaning that no memory from a store will be deallocated until you call
* #wasmtime_store_delete. If you're working with a web server, for example,
* then it's recommended to think of a store as a "one per request" sort of
* construct. Globally you'd have one #wasm_engine_t and a cache of
* #wasmtime_module_t instances compiled into that engine. Each request would
* create a new #wasmtime_store_t and then instantiate a #wasmtime_module_t
* into the store. This process of creating a store and instantiating a module
* is expected to be quite fast. When the request is finished you'd delete the
* #wasmtime_store_t keeping memory usage reasonable for the lifetime of the
* server.
*/
#ifndef WASMTIME_API_H
#define WASMTIME_API_H
#include <wasi.h>
#include <wasmtime/conf.h>
// clang-format off
// IWYU pragma: begin_exports
#include <wasmtime/config.h>
#include <wasmtime/engine.h>
#include <wasmtime/error.h>
#include <wasmtime/extern.h>
#include <wasmtime/func.h>
#include <wasmtime/global.h>
#include <wasmtime/instance.h>
#include <wasmtime/linker.h>
#include <wasmtime/memory.h>
#include <wasmtime/module.h>
#include <wasmtime/profiling.h>
#include <wasmtime/sharedmemory.h>
#include <wasmtime/store.h>
#include <wasmtime/table.h>
#include <wasmtime/trap.h>
#include <wasmtime/val.h>
#include <wasmtime/async.h>
// IWYU pragma: end_exports
// clang-format on
/**
* \brief Wasmtime version string.
*/
#define WASMTIME_VERSION "26.0.1"
/**
* \brief Wasmtime major version number.
*/
#define WASMTIME_VERSION_MAJOR 26
/**
* \brief Wasmtime minor version number.
*/
#define WASMTIME_VERSION_MINOR 0
/**
* \brief Wasmtime patch version number.
*/
#define WASMTIME_VERSION_PATCH 1
#ifdef __cplusplus
extern "C" {
#endif
#ifdef WASMTIME_FEATURE_WAT
/**
* \brief Converts from the text format of WebAssembly to the binary format.
*
* \param wat this it the input pointer with the WebAssembly Text Format inside
* of it. This will be parsed and converted to the binary format.
* \param wat_len this it the length of `wat`, in bytes.
* \param ret if the conversion is successful, this byte vector is filled in
* with the WebAssembly binary format.
*
* \return a non-null error if parsing fails, or returns `NULL`. If parsing
* fails then `ret` isn't touched.
*
* This function does not take ownership of `wat`, and the caller is expected to
* deallocate the returned #wasmtime_error_t and #wasm_byte_vec_t.
*/
WASM_API_EXTERN wasmtime_error_t *
wasmtime_wat2wasm(const char *wat, size_t wat_len, wasm_byte_vec_t *ret);
#endif
#ifdef __cplusplus
} // extern "C"
#endif
#endif // WASMTIME_API_H
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