Add some docs

docs/api/cc.md

@@ -0,0 +1,197 @@
+`bun:ffi` has experimental support for compiling and running C from JavaScript with low overhead.
+
+## Usage (cc in `bun:ffi`)
+
+See the [introduction blog post](https://bun.sh/blog/compile-and-run-c-in-js) for more information.
+
+JavaScript:
+
+```ts#hello.js
+import { cc } from "bun:ffi";
+import source from "./hello.c" with { type: "file" };
+
+const {
+ symbols: { hello },
+} = cc({
+ source,
+ symbols: {
+ hello: {
+ args: [],
+ returns: "int",
+ },
+ },
+});
+
+console.log("What is the answer to the universe?", hello());
+```
+
+C source:
+
+```c#hello.c
+int hello() {
+ return 42;
+}
+```
+
+When you run `hello.js`, it will print:
+
+```sh
+$ bun hello.js
+What is the answer to the universe? 42
+```
+
+Under the hood, `cc` uses [TinyCC](https://bellard.org/tcc/) to compile the C code and then link it with the JavaScript runtime, efficiently converting types in-place.
+
+### Primitive types
+
+The same `FFIType` values in [`dlopen`](/docs/api/ffi) are supported in `cc`.
+
+| `FFIType` | C Type | Aliases |
+| ---------- | -------------- | --------------------------- |
+| cstring | `char*` | |
+| function | `(void*)(*)()` | `fn`, `callback` |
+| ptr | `void*` | `pointer`, `void*`, `char*` |
+| i8 | `int8_t` | `int8_t` |
+| i16 | `int16_t` | `int16_t` |
+| i32 | `int32_t` | `int32_t`, `int` |
+| i64 | `int64_t` | `int64_t` |
+| i64_fast | `int64_t` | |
+| u8 | `uint8_t` | `uint8_t` |
+| u16 | `uint16_t` | `uint16_t` |
+| u32 | `uint32_t` | `uint32_t` |
+| u64 | `uint64_t` | `uint64_t` |
+| u64_fast | `uint64_t` | |
+| f32 | `float` | `float` |
+| f64 | `double` | `double` |
+| bool | `bool` | |
+| char | `char` | |
+| napi_env | `napi_env` | |
+| napi_value | `napi_value` | |
+
+### Strings, objects, and non-primitive types
+
+To make it easier to work with strings, objects, and other non-primitive types that don't map 1:1 to C types, `cc` supports N-API.
+
+To pass or receive a JavaScript values without any type conversions from a C function, you can use `napi_value`.
+
+You can also pass a `napi_env` to receive the N-API environment used to call the JavaScript function.
+
+#### Returning a C string to JavaScript
+
+For example, if you have a string in C, you can return it to JavaScript like this:
+
+```ts#hello.js
+import { cc } from "bun:ffi";
+import source from "./hello.c" with { type: "file" };
+
+const {
+ symbols: { hello },
+} = cc({
+ source,
+ symbols: {
+ hello: {
+ args: ["napi_env"],
+ returns: "napi_value",
+ },
+ },
+});
+
+const result = hello();
+```
+
+And in C:
+
+```c#hello.c
+#include <node/node_api.h>
+
+napi_value hello(napi_env env) {
+ napi_value result;
+ napi_create_string_utf8(env, "Hello, Napi!", NAPI_AUTO_LENGTH, &result);
+ return result;
+}
+```
+
+You can also use this to return other types like objects and arrays:
+
+```c#hello.c
+#include <node/node_api.h>
+
+napi_value hello(napi_env env) {
+ napi_value result;
+ napi_create_object(env, &result);
+ return result;
+}
+```
+
+### `cc` Reference
+
+#### `library: string[]`
+
+The `library` array is used to specify the libraries that should be linked with the C code.
+
+```ts
+type Library = string[];
+
+cc({
+ source: "hello.c",
+ library: ["sqlite3"],
+});
+```
+
+#### `symbols`
+
+The `symbols` object is used to specify the functions and variables that should be exposed to JavaScript.
+
+```ts
+type Symbols = {
+ [key: string]: {
+ args: FFIType[];
+ returns: FFIType;
+ };
+};
+```
+
+#### `source`
+
+The `source` is a file path to the C code that should be compiled and linked with the JavaScript runtime.
+
+```ts
+type Source = string | URL | BunFile;
+
+cc({
+ source: "hello.c",
+ symbols: {
+ hello: {
+ args: [],
+ returns: "int",
+ },
+ },
+});
+```
+
+#### `flags: string | string[]`
+
+The `flags` is an optional array of strings that should be passed to the TinyCC compiler.
+
+```ts
+type Flags = string | string[];
+```
+
+These are flags like `-I` for include directories and `-D` for preprocessor definitions.
+
+#### `defines: Record<string, string>`
+
+The `defines` is an optional object that should be passed to the TinyCC compiler.
+
+```ts
+type Defines = Record<string, string>;
+
+cc({
+ source: "hello.c",
+ defines: {
+ "NDEBUG": "1",
+ },
+});
+```
+
+These are preprocessor definitions passed to the TinyCC compiler.

docs/api/ffi.md

@@ -1,6 +1,6 @@
 Use the built-in `bun:ffi` module to efficiently call native libraries from JavaScript. It works with languages that support the C ABI (Zig, Rust, C/C++, C#, Nim, Kotlin, etc).
 
-## Usage (`bun:ffi`)
+## dlopen usage (`bun:ffi`)
 
 To print the version number of `sqlite3`:
 
@@ -108,25 +108,27 @@ $ zig build-lib add.cpp -dynamic -lc -lc++
 
 The following `FFIType` values are supported.
 
-| `FFIType` | C Type | Aliases |
-| --------- | -------------- | --------------------------- |
-| cstring | `char*` | |
-| function | `(void*)(*)()` | `fn`, `callback` |
-| ptr | `void*` | `pointer`, `void*`, `char*` |
-| i8 | `int8_t` | `int8_t` |
-| i16 | `int16_t` | `int16_t` |
-| i32 | `int32_t` | `int32_t`, `int` |
-| i64 | `int64_t` | `int64_t` |
-| i64_fast | `int64_t` | |
-| u8 | `uint8_t` | `uint8_t` |
-| u16 | `uint16_t` | `uint16_t` |
-| u32 | `uint32_t` | `uint32_t` |
-| u64 | `uint64_t` | `uint64_t` |
-| u64_fast | `uint64_t` | |
-| f32 | `float` | `float` |
-| f64 | `double` | `double` |
-| bool | `bool` | |
-| char | `char` | |
+| `FFIType` | C Type | Aliases |
+| ---------- | -------------- | --------------------------- |
+| cstring | `char*` | |
+| function | `(void*)(*)()` | `fn`, `callback` |
+| ptr | `void*` | `pointer`, `void*`, `char*` |
+| i8 | `int8_t` | `int8_t` |
+| i16 | `int16_t` | `int16_t` |
+| i32 | `int32_t` | `int32_t`, `int` |
+| i64 | `int64_t` | `int64_t` |
+| i64_fast | `int64_t` | |
+| u8 | `uint8_t` | `uint8_t` |
+| u16 | `uint16_t` | `uint16_t` |
+| u32 | `uint32_t` | `uint32_t` |
+| u64 | `uint64_t` | `uint64_t` |
+| u64_fast | `uint64_t` | |
+| f32 | `float` | `float` |
+| f64 | `double` | `double` |
+| bool | `bool` | |
+| char | `char` | |
+| napi_env | `napi_env` | |
+| napi_value | `napi_value` | |
 
 ## Strings