Merge branch 'getpagesize-panic' into 'master'

Panic when getpagesize() cannot succeed as specified

See merge request redox-os/relibc!455

src/header/unistd/mod.rs

@@ -443,21 +443,10 @@ pub extern "C" fn getlogin_r(name: *mut c_char, namesize: size_t) -> c_int {
 
 #[no_mangle]
 pub extern "C" fn getpagesize() -> c_int {
-    match c_int::try_from(sysconf(_SC_PAGESIZE)) {
-        Ok(page_size) => page_size,
-        Err(_) => {
-            /* Behavior not specified by POSIX for this case. The -1
-             * value mimics sysconf()'s behavior, though.
-             *
-             * As specified for the limits.h header, the minimum
-             * acceptable value for {PAGESIZE} is 1. The -1 value thus
-             * cannot be mistaken for an acceptable value.
-             *
-             * POSIX does not specify any possible errors for this
-             * function, hence no errno setting. */
-            -1
-        }
-    }
+    // Panic if we can't uphold the required behavior (no errors are specified for this function)
+    Sys::getpagesize()
+        .try_into()
+        .expect("page size not representable as type `int`")
 }
 
 // #[no_mangle]

tests/unistd/getpagesize.c

@@ -5,10 +5,7 @@
 #include "test_helpers.h"
 
 int main(void) {
-    errno = 0;
     int getpagesize_result = getpagesize();
-    int getpagesize_errno = errno;
-    
-    printf("getpagesize(): %d, errno: %d = %s\n", getpagesize_result,
-        getpagesize_errno, strerror(getpagesize_errno));
+
+    printf("Page size: %d\n", getpagesize_result);
 }