run gz api tests with miri

Author: folkertdev

.github/workflows/checks.yaml

@@ -490,11 +490,18 @@ jobs:
           RUSTFLAGS: "-Ctarget-feature=+avx2,+bmi2,+bmi1"
       - name: Test allocator with miri
         run: "cargo +nightly miri nextest run -j4 -p zlib-rs --target ${{ matrix.target }} allocate::"
-      - name: Test gz logic with miri
+      - name: Test allocator with miri
+        run: "cargo +nightly miri nextest run -j4 -p zlib-rs --target ${{ matrix.target }} allocate::"
+      - name: Test gz internals with miri
         working-directory: libz-rs-sys-cdylib
         run: "cargo +nightly miri nextest run -j4 -p libz-rs-sys-cdylib --target ${{ matrix.target }} --features=gz"
         env:
           MIRIFLAGS: "-Zmiri-tree-borrows -Zmiri-disable-isolation"
+      - name: Test gz api with miri
+        if: ${{ contains(matrix.target, 'linux') }}
+        run: "cargo +nightly miri nextest run -j4 -p test-libz-rs-sys --target ${{ matrix.target }} gz::"
+        env:
+          MIRIFLAGS: "-Zmiri-disable-isolation"
 
   miri-avx512:
     name: "Miri avx512"

libz-rs-sys-cdylib/src/gz.rs

@@ -1809,29 +1809,27 @@ fn gz_init(state: &mut GzState) -> Result<(), ()> {
 }
 
 #[cfg(not(miri))]
-unsafe fn write(fd: c_int, buf: *const c_void, count: size_t) -> libc::ssize_t {
-    unsafe { libc::write(fd, buf, count) }
-}
+use libc::write;
 
 /// Deal with miri often not writing the full buffer in one go. That is valid, but zlib assumes
 /// that writes are to true files and succeed unless e.g. the disk is full.
 #[cfg(miri)]
 unsafe fn write(fd: c_int, buf: *const c_void, count: size_t) -> libc::ssize_t {
-    let mut total_written = 0isize;
+    let mut total_written: libc::ssize_t = 0;
     loop {
         let ret = unsafe {
             libc::write(
                 fd,
                 buf.add(total_written as usize),
-                count - total_written as usize,
+                (count - total_written as size_t) as _,
             )
         };
 
         match ret.cmp(&0) {
-            Ordering::Less => return ret,
+            Ordering::Less => return ret as libc::ssize_t,
             Ordering::Equal => return total_written,
             Ordering::Greater => {
-                total_written += ret;
+                total_written += ret as libc::ssize_t;
 
                 if total_written as usize == count {
                     break;

test-libz-rs-sys/src/gz.rs

@@ -36,31 +36,29 @@ fn binary_mode(mode: c_int) -> c_int {
 }
 
 #[cfg(not(miri))]
-unsafe fn write(fd: c_int, buf: *const c_void, count: size_t) -> libc::ssize_t {
-    unsafe { libc::write(fd, buf, count) }
-}
+use libc::write;
 
 /// Deal with miri often not writing the full buffer in one go. That is valid, but zlib assumes
 /// that writes are to true files and succeed unless e.g. the disk is full.
 #[cfg(miri)]
 unsafe fn write(fd: c_int, buf: *const c_void, count: size_t) -> libc::ssize_t {
     use std::cmp::Ordering;
 
-    let mut total_written = 0isize;
+    let mut total_written: libc::ssize_t = 0;
     loop {
         let ret = unsafe {
             libc::write(
                 fd,
                 buf.add(total_written as usize),
-                count - total_written as usize,
+                (count - total_written as size_t) as _,
             )
         };
 
         match ret.cmp(&0) {
-            Ordering::Less => return ret,
+            Ordering::Less => return ret as libc::ssize_t,
             Ordering::Equal => return total_written,
             Ordering::Greater => {
-                total_written += ret;
+                total_written += ret as libc::ssize_t;
 
                 if total_written as usize == count {
                     break;