libuv: win/spawn: optionally run executable paths with no file extension

Backport libuv commit `3f7191e5` (win/spawn: optionally run executable
paths with no file extension, 2024-02-05, v1.48.0~8) to add the
`UV_PROCESS_WINDOWS_FILE_PATH_EXACT_NAME` option we now use.

Issue: #25450

Source/cmUVProcessChain.cxx

@@ -311,7 +311,9 @@ void cmUVProcessChain::InternalData::SpawnProcess(
   arguments.push_back(nullptr);
   options.args = const_cast<char**>(arguments.data());
   options.flags = UV_PROCESS_WINDOWS_HIDE;
-#if UV_VERSION_MAJOR > 1 || (UV_VERSION_MAJOR == 1 && UV_VERSION_MINOR >= 48)
+#if UV_VERSION_MAJOR > 1 ||                                                   \
+  (UV_VERSION_MAJOR == 1 && UV_VERSION_MINOR >= 48) ||                        \
+  !defined(CMAKE_USE_SYSTEM_LIBUV)
   options.flags |= UV_PROCESS_WINDOWS_FILE_PATH_EXACT_NAME;
 #endif
   if (!this->Builder->WorkingDirectory.empty()) {

Utilities/cmlibuv/include/uv.h

@@ -1080,7 +1080,14 @@ enum uv_process_flags {
    * option is only meaningful on Windows systems. On Unix it is silently
    * ignored.
    */
-  UV_PROCESS_WINDOWS_HIDE_GUI = (1 << 6)
+  UV_PROCESS_WINDOWS_HIDE_GUI = (1 << 6),
+  /*
+   * On Windows, if the path to the program to execute, specified in
+   * uv_process_options_t's file field, has a directory component,
+   * search for the exact file name before trying variants with
+   * extensions like '.exe' or '.cmd'.
+   */
+  UV_PROCESS_WINDOWS_FILE_PATH_EXACT_NAME = (1 << 7)
 };
 
 /*

Utilities/cmlibuv/src/unix/process.c

@@ -1008,6 +1008,7 @@ int uv_spawn(uv_loop_t* loop,
   assert(!(options->flags & ~(UV_PROCESS_DETACHED |
                               UV_PROCESS_SETGID |
                               UV_PROCESS_SETUID |
+                              UV_PROCESS_WINDOWS_FILE_PATH_EXACT_NAME |
                               UV_PROCESS_WINDOWS_HIDE |
                               UV_PROCESS_WINDOWS_HIDE_CONSOLE |
                               UV_PROCESS_WINDOWS_HIDE_GUI |

Utilities/cmlibuv/src/win/process.c

@@ -329,8 +329,9 @@ static WCHAR* path_search_walk_ext(const WCHAR *dir,
  * - If there's really only a filename, check the current directory for file,
  *   then search all path directories.
  *
- * - If filename specified has *any* extension, search for the file with the
- *   specified extension first.
+ * - If filename specified has *any* extension, or already contains a path
+ *   and the UV_PROCESS_WINDOWS_FILE_PATH_EXACT_NAME flag is specified,
+ *   search for the file with the exact specified filename first.
  *
  * - If the literal filename is not found in a directory, try *appending*
  *   (not replacing) .com first and then .exe.
@@ -356,7 +357,8 @@ static WCHAR* path_search_walk_ext(const WCHAR *dir,
  */
 static WCHAR* search_path(const WCHAR *file,
                             WCHAR *cwd,
-                            const WCHAR *path) {
+                            const WCHAR *path,
+                            unsigned int flags) {
   int file_has_dir;
   WCHAR* result = NULL;
   WCHAR *file_name_start;
@@ -397,7 +399,7 @@ static WCHAR* search_path(const WCHAR *file,
         file, file_name_start - file,
         file_name_start, file_len - (file_name_start - file),
         cwd, cwd_len,
-        name_has_ext);
+        name_has_ext || (flags & UV_PROCESS_WINDOWS_FILE_PATH_EXACT_NAME));
 
   } else {
     dir_end = path;
@@ -987,6 +989,7 @@ int uv_spawn(uv_loop_t* loop,
   assert(!(options->flags & ~(UV_PROCESS_DETACHED |
                               UV_PROCESS_SETGID |
                               UV_PROCESS_SETUID |
+                              UV_PROCESS_WINDOWS_FILE_PATH_EXACT_NAME |
                               UV_PROCESS_WINDOWS_HIDE |
                               UV_PROCESS_WINDOWS_HIDE_CONSOLE |
                               UV_PROCESS_WINDOWS_HIDE_GUI |
@@ -1066,7 +1069,8 @@ int uv_spawn(uv_loop_t* loop,
 
   application_path = search_path(application,
                                  cwd,
-                                 path);
+                                 path,
+                                 options->flags);
   if (application_path == NULL) {
     /* Not found. */
     err = ERROR_FILE_NOT_FOUND;