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tutorial: Update with native module syntax change

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Haitao Li 2011-11-16 23:28:15 +08:00 committed by Brian Anderson
parent 88f29aab27
commit 5665308d8c
1 changed files with 20 additions and 11 deletions
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31
doc/tutorial/ffi.md
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@ -15,7 +15,8 @@ OpenSSL libraries installed, it should 'just work'.
use std;
import std::{vec, str};
native "cdecl" mod crypto {
#[abi = "cdecl"]
native mod crypto {
fn SHA1(src: *u8, sz: uint, out: *u8) -> *u8;
}
@ -41,7 +42,8 @@ OpenSSL libraries installed, it should 'just work'.
Before we can call `SHA1`, we have to declare it. That is what this
part of the program is responsible for:
native "cdecl" mod crypto {
#[abi = "cdecl"]
native mod crypto {
fn SHA1(src: *u8, sz: uint, out: *u8) -> *u8;
}
@ -52,12 +54,17 @@ of functions are available in that library.
In this case, it'll change the name `crypto` to a shared library name
in a platform-specific way (`libcrypto.so` on Linux, for example), and
link that in. If you want the module to have a different name from the
actual library, you can say `native "cdecl" mod something = "crypto" {
... }`.
actual library, you can use the `"link_name"` attribute, like:
The `"cdecl"` word indicates the calling convention to use for
functions in this module. Most C libraries use cdecl as their calling
convention. You can also specify `"x86stdcall"` to use stdcall
#[abi = "cdecl"]
#[link_name = "crypto"]
native mod something {
fn SHA1(src: *u8, sz: uint, out: *u8) -> *u8;
}
The `#[abi = "cdecl"]` attribute indicates the calling convention to
use for functions in this module. Most C libraries use cdecl as their
calling convention. You can also specify `"x86stdcall"` to use stdcall
instead.
FIXME: Mention c-stack variants? Are they going to change?
@ -164,7 +171,9 @@ microsecond-resolution timer.
use std;
type timeval = {mutable tv_sec: u32,
mutable tv_usec: u32};
native "cdecl" mod libc = "" {
#[abi = "cdecl"]
#[link_name = ""]
native mod libc {
fn gettimeofday(tv: *timeval, tz: *()) -> i32;
}
fn unix_time_in_microseconds() -> u64 unsafe {
@ -173,9 +182,9 @@ microsecond-resolution timer.
ret (x.tv_sec as u64) * 1000_000_u64 + (x.tv_usec as u64);
}
The `libc = ""` sets the name of the native module to the empty string
to prevent the rust compiler from trying to link it. The standard C
library is already linked with Rust programs.
The `#[link_name = ""]` sets the name of the native module to the
empty string to prevent the rust compiler from trying to link it.
The standard C library is already linked with Rust programs.
A `timeval`, in C, is a struct with two 32-bit integers. Thus, we
define a record type with the same contents, and declare