Add cygwin support

Cargo.toml

@@ -38,7 +38,7 @@ cpp_demangle = { default-features = false, version = "0.4.0", optional = true, f
   "alloc",
 ] }
 
-[target.'cfg(windows)'.dependencies]
+[target.'cfg(any(windows, target_os = "cygwin"))'.dependencies]
 windows-targets = "0.52.6"
 
 [target.'cfg(not(all(windows, target_env = "msvc", not(target_vendor = "uwp"))))'.dependencies]

src/lib.rs

@@ -247,5 +247,5 @@ mod lock {
 ))]
 mod dbghelp;
 // Auto-generated by windows-bindgen/riddle
-#[cfg(windows)]
+#[cfg(any(windows, target_os = "cygwin"))]
 mod windows_sys;

src/symbolize/gimli.rs

@@ -193,7 +193,7 @@ fn mmap(path: &Path) -> Option<Mmap> {
 }
 
 cfg_if::cfg_if! {
-    if #[cfg(windows)] {
+    if #[cfg(any(windows, target_os = "cygwin"))] {
         mod coff;
         use self::coff::{handle_split_dwarf, Object};
     } else if #[cfg(any(target_vendor = "apple"))] {
@@ -209,7 +209,7 @@ cfg_if::cfg_if! {
 }
 
 cfg_if::cfg_if! {
-    if #[cfg(windows)] {
+    if #[cfg(any(windows, target_os = "cygwin"))] {
         mod libs_windows;
         use libs_windows::native_libraries;
     } else if #[cfg(target_vendor = "apple")] {

src/symbolize/gimli/libs_windows.rs

@@ -1,6 +1,5 @@
 use super::super::super::windows_sys::*;
 use super::mystd::ffi::OsString;
-use super::mystd::os::windows::prelude::*;
 use super::{coff, mmap, Library, LibrarySegment};
 use alloc::vec;
 use alloc::vec::Vec;
@@ -49,7 +48,37 @@ unsafe fn load_library(me: &MODULEENTRY32W) -> Option<Library> {
         .iter()
         .position(|i| *i == 0)
         .unwrap_or(me.szExePath.len());
-    let name = OsString::from_wide(&me.szExePath[..pos]);
+    let name_len = unsafe {
+        WideCharToMultiByte(
+            CP_UTF8,
+            0,
+            me.szExePath.as_ptr(),
+            pos as i32,
+            core::ptr::null_mut(),
+            0,
+            core::ptr::null_mut(),
+            core::ptr::null_mut(),
+        ) 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
+    };
+    if name_len == 0 || name_len > name_buffer.len() {
+        // This can't happen.
+        return None;
+    }
+    unsafe { name_buffer.set_len(name_len) };
+    let name = unsafe { OsString::from_encoded_bytes_unchecked(name_buffer) };
 
     // MinGW libraries currently don't support ASLR
     // (rust-lang/rust#16514), but DLLs can still be relocated around in