From 0b2c3fe5ea9d4d07cd5345ad00226a6809e39606 Mon Sep 17 00:00:00 2001
From: Peter Limkilde Svendsen <peter.limkilde@gmail.com>
Date: Thu, 14 Nov 2019 02:46:53 +0000
Subject: [PATCH] Implement wcsstr(), fix return type of wcslen()
---
src/header/wchar/mod.rs | 37 ++++++++++++++++++++++++------
tests/Makefile | 1 +
tests/expected/wchar/wcsstr.stderr | 0
tests/expected/wchar/wcsstr.stdout | 0
tests/wchar/wcsstr.c | 27 ++++++++++++++++++++++
5 files changed, 58 insertions(+), 7 deletions(-)
create mode 100644 tests/expected/wchar/wcsstr.stderr
create mode 100644 tests/expected/wchar/wcsstr.stdout
create mode 100644 tests/wchar/wcsstr.c
diff --git a/src/header/wchar/mod.rs b/src/header/wchar/mod.rs
index dd3d00714..8d63325f9 100644
--- a/src/header/wchar/mod.rs
+++ b/src/header/wchar/mod.rs
@@ -1,6 +1,6 @@
//! wchar implementation for Redox, following http://pubs.opengroup.org/onlinepubs/7908799/xsh/wchar.h.html
-use core::{char, ffi::VaList as va_list, mem, ptr, usize};
+use core::{char, ffi::VaList as va_list, mem, ptr, slice, usize};
use crate::{
header::{ctype::isspace, errno::ERANGE, stdio::*, stdlib::MB_CUR_MAX, string, time::*},
@@ -353,11 +353,11 @@ pub extern "C" fn wcsftime(
}
#[no_mangle]
-pub unsafe extern "C" fn wcslen(ws: *const wchar_t) -> c_ulong {
+pub unsafe extern "C" fn wcslen(ws: *const wchar_t) -> size_t {
let mut i = 0;
loop {
if *ws.add(i) == 0 {
- return i as c_ulong;
+ return i;
}
i += 1;
}
@@ -370,7 +370,7 @@ pub unsafe extern "C" fn wcsncat(
n: size_t,
) -> *mut wchar_t {
let len = wcslen(ws1);
- let dest = ws1.add(len as usize);
+ let dest = ws1.add(len);
let mut i = 0;
while i < n {
let wc = *ws2.add(i);
@@ -462,9 +462,32 @@ pub unsafe extern "C" fn wcsspn(wcs: *const wchar_t, set: *const wchar_t) -> siz
inner_wcsspn(wcs, set, false)
}
-// #[no_mangle]
-pub extern "C" fn wcsstr(ws1: *const wchar_t, ws2: *const wchar_t) -> *mut wchar_t {
- unimplemented!();
+#[no_mangle]
+pub unsafe extern "C" fn wcsstr(ws1: *const wchar_t, ws2: *const wchar_t) -> *mut wchar_t {
+ // Get length of ws2, not including null terminator
+ let ws2_len = wcslen(ws2);
+
+ // The standard says that we must return ws1 if ws2 has length 0
+ if ws2_len == 0 {
+ ws1 as *mut wchar_t
+ } else {
+ let ws1_len = wcslen(ws1);
+
+ // Construct slices without null terminator
+ let ws1_slice = slice::from_raw_parts(ws1, ws1_len);
+ let ws2_slice = slice::from_raw_parts(ws2, ws2_len);
+
+ /* Sliding ws2-sized window iterator on ws1. The iterator
+ * returns None if ws2 is longer than ws1. */
+ let mut ws1_windows = ws1_slice.windows(ws2_len);
+
+ /* Find the first offset into ws1 where the window is equal to
+ * the ws2 contents. Return null pointer if no match is found. */
+ match ws1_windows.position(|ws1_window| ws1_window == ws2_slice) {
+ Some(pos) => ws1.add(pos) as *mut wchar_t,
+ None => ptr::null_mut(),
+ }
+ }
}
macro_rules! skipws {
diff --git a/tests/Makefile b/tests/Makefile
index 106923349..ebb38d485 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -95,6 +95,7 @@ EXPECT_NAMES=\
wchar/wcrtomb \
wchar/wcscspn \
wchar/wcsrchr \
+ wchar/wcsstr \
wchar/wcstod \
wchar/wcstok \
wchar/wcstol \
diff --git a/tests/expected/wchar/wcsstr.stderr b/tests/expected/wchar/wcsstr.stderr
new file mode 100644
index 000000000..e69de29bb
diff --git a/tests/expected/wchar/wcsstr.stdout b/tests/expected/wchar/wcsstr.stdout
new file mode 100644
index 000000000..e69de29bb
diff --git a/tests/wchar/wcsstr.c b/tests/wchar/wcsstr.c
new file mode 100644
index 000000000..b49a4baac
--- /dev/null
+++ b/tests/wchar/wcsstr.c
@@ -0,0 +1,27 @@
+#include <assert.h>
+#include <wchar.h>
+
+int main(void) {
+ wchar_t *haystack = L"Hello, World!";
+ wchar_t *haystack_empty = L"";
+
+ wchar_t *needle_expected = L"World";
+ wchar_t *needle_expected_multiple = L"l";
+ wchar_t *needle_not_expected = L"Rust";
+ wchar_t *needle_too_long = L"Hello, World!!!";
+ wchar_t *needle_empty = L"";
+
+ assert(wcsstr(haystack, needle_expected) == haystack + 7);
+ assert(wcsstr(haystack, needle_expected_multiple) == haystack + 2);
+ assert(wcsstr(haystack, needle_not_expected) == NULL);
+ assert(wcsstr(haystack, needle_too_long) == NULL);
+ assert(wcsstr(haystack, needle_empty) == haystack);
+
+ assert(wcsstr(haystack_empty, needle_expected) == NULL);
+ assert(wcsstr(haystack_empty, needle_expected_multiple) == NULL);
+ assert(wcsstr(haystack_empty, needle_not_expected) == NULL);
+ assert(wcsstr(haystack_empty, needle_too_long) == NULL);
+ assert(wcsstr(haystack_empty, needle_empty) == haystack_empty);
+
+ return 0;
+}
--
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