Convert path to posix

Author: Berrysoft

src/symbolize/gimli.rs

@@ -43,6 +43,7 @@ cfg_if::cfg_if! {
         target_os = "solaris",
         target_os = "illumos",
         target_os = "aix",
+        target_os = "cygwin",
     ))] {
         #[path = "gimli/mmap_unix.rs"]
         mod mmap;

src/symbolize/gimli/libs_windows.rs

@@ -1,5 +1,7 @@
 use super::super::super::windows_sys::*;
 use super::mystd::ffi::OsString;
+#[cfg(windows)]
+use super::mystd::os::windows::prelude::*;
 use super::{coff, mmap, Library, LibrarySegment};
 use alloc::vec;
 use alloc::vec::Vec;
@@ -42,43 +44,64 @@ unsafe fn add_loaded_images(ret: &mut Vec<Library>) {
     }
 }
 
-unsafe fn load_library(me: &MODULEENTRY32W) -> Option<Library> {
-    let pos = me
-        .szExePath
-        .iter()
-        .position(|i| *i == 0)
-        .unwrap_or(me.szExePath.len());
+// Safety: long_path should be null-terminated
+#[cfg(target_os = "cygwin")]
+unsafe fn get_posix_path(long_path: &[u16]) -> Option<OsString> {
+    use std::os::unix::ffi::OsStringExt;
+
+    unsafe extern "C" {
+        fn cygwin_conv_path(
+            what: libc::c_uint,
+            from: *const libc::c_void,
+            to: *mut libc::c_void,
+            size: libc::size_t,
+        ) -> libc::ssize_t;
+    }
+    const CCP_WIN_W_TO_POSIX: libc::c_uint = 3;
+
     let name_len = unsafe {
-        WideCharToMultiByte(
-            CP_UTF8,
-            0,
-            me.szExePath.as_ptr(),
-            pos as i32,
+        cygwin_conv_path(
+            CCP_WIN_W_TO_POSIX,
+            long_path.as_ptr().cast(),
             core::ptr::null_mut(),
             0,
-            core::ptr::null_mut(),
-            core::ptr::null_mut(),
-        ) as usize
+        )
     };
+    // Expect at least 1 for null terminator.
+    if name_len < 1 {
+        return None;
+    }
+    let name_len = name_len as usize;
     let mut name_buffer = vec![0_u8; name_len];
-    let name_len = unsafe {
-        WideCharToMultiByte(
-            CP_UTF8,
-            0,
-            me.szExePath.as_ptr(),
-            pos as i32,
-            name_buffer.as_mut_ptr(),
-            name_buffer.len() as i32,
-            core::ptr::null_mut(),
-            core::ptr::null_mut(),
-        ) as usize
+    let res = unsafe {
+        cygwin_conv_path(
+            CCP_WIN_W_TO_POSIX,
+            long_path.as_ptr().cast(),
+            name_buffer.as_mut_ptr().cast(),
+            name_buffer.len(),
+        )
     };
-    if name_len == 0 || name_len > name_buffer.len() {
-        // This can't happen.
+    if res != 0 {
         return None;
     }
-    unsafe { name_buffer.set_len(name_len) };
-    let name = unsafe { OsString::from_encoded_bytes_unchecked(name_buffer) };
+    // Ignore null terminator.
+    unsafe { name_buffer.set_len(name_len - 1) };
+    let name = OsString::from_vec(name_buffer);
+    Some(name)
+}
+
+unsafe fn load_library(me: &MODULEENTRY32W) -> Option<Library> {
+    let pos = me
+        .szExePath
+        .iter()
+        .position(|i| *i == 0)
+        .unwrap_or(me.szExePath.len());
+    #[cfg(windows)]
+    let name = OsString::from_wide(&me.szExePath[..pos]);
+    #[cfg(target_os = "cygwin")]
+    // Safety: the path with max length MAX_PATH always contains a null
+    // terminator
+    let name = unsafe { get_posix_path(&me.szExePath[..pos])? };
 
     // MinGW libraries currently don't support ASLR
     // (rust-lang/rust#16514), but DLLs can still be relocated around in