Initial get_results_iter implementation

wooster0 · May 17, 2021 · 9036798 · 9036798
1 parent a980e60
commit 9036798
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Showing 3 changed files with 88 additions and 33 deletions.
diff --git a/src/backend/gtk3/file_dialog/dialog_ffi.rs b/src/backend/gtk3/file_dialog/dialog_ffi.rs
@@ -100,6 +100,10 @@ impl GtkFileDialog {
     }
 
     pub fn get_results(&self) -> Vec<PathBuf> {
+        self.get_results_iter().collect()
+    }
+
+    pub fn get_results_iter(&self) -> impl Iterator<Item = PathBuf> {
         #[derive(Debug)]
         struct FileList(*mut glib_sys::GSList);
 
@@ -123,17 +127,15 @@ impl GtkFileDialog {
         let chosen_filenames =
             unsafe { gtk_sys::gtk_file_chooser_get_filenames(self.ptr as *mut _) };
 
-        let paths: Vec<PathBuf> = FileList(chosen_filenames)
-            .filter_map(|item| {
-                let cstr = unsafe { CStr::from_ptr(item.data as _).to_str() };
+        let paths = FileList(chosen_filenames).filter_map(|item| {
+            let cstr = unsafe { CStr::from_ptr(item.data as _).to_str() };
 
-                if let Ok(cstr) = cstr {
-                    Some(PathBuf::from(cstr.to_owned()))
-                } else {
-                    None
-                }
-            })
-            .collect();
+            if let Ok(cstr) = cstr {
+                Some(PathBuf::from(cstr.to_owned()))
+            } else {
+                None
+            }
+        });
 
         paths
     }

diff --git a/src/backend/macos/file_dialog/panel_ffi.rs b/src/backend/macos/file_dialog/panel_ffi.rs
@@ -118,16 +118,47 @@ impl Panel {
     }
 
     pub fn get_results(&self) -> Vec<PathBuf> {
+        get_results_iter().collect()
+    }
+
+    pub fn get_results_iter(&self) -> impl Iterator<Item = PathBuf> {
+        struct FileList {
+            count: usize,
+            urls: Id<NSArray<NSURL>>,
+        }
+
+        impl FileList {
+            fn new(urls: Vec<Id<NSArray<NSURL>>>) {
+                FileList {
+                    count: urls.len(),
+                    urls,
+                }
+            }
+        }
+
+        impl Iterator for FileList {
+            type Item = Id<NSArray<NSURL>>;
+
+            fn next(&mut self) -> Option<PathBuf> {
+                let curr_ptr = self.0;
+
+                if !curr_ptr.is_null() {
+                    let curr = unsafe { *curr_ptr };
+
+                    self.0 = curr.next;
+
+                    Some(curr)
+                } else {
+                    None
+                }
+            }
+        }
+
         unsafe {
             let urls = msg_send![self.panel, URLs];
             let urls: Id<NSArray<NSURL>> = Id::from_ptr(urls);
 
-            let mut res = Vec::new();
-            for url in urls.to_vec() {
-                res.push(url.to_path_buf());
-            }
-
-            res
+            FileList::new(urls.to_vec())
         }
     }
 }

diff --git a/src/backend/win_cid/file_dialog/dialog_ffi.rs b/src/backend/win_cid/file_dialog/dialog_ffi.rs
@@ -154,33 +154,55 @@ impl IDialog {
         Ok(())
     }
 
-    pub fn get_results(&self) -> Result<Vec<PathBuf>, HRESULT> {
-        unsafe {
-            let mut res_items: *mut IShellItemArray = ptr::null_mut();
-            (*(self.0 as *mut IFileOpenDialog))
-                .GetResults(&mut res_items)
-                .check()?;
+    pub fn get_results_iter(&self) -> Result<impl Iterator<Item = PathBuf>, HRESULT> {
+        struct FileList {
+            items: *mut IShellItemArray,
+            count: usize,
+        }
+
+        impl FileList {
+            fn new(item_array: *mut IFileDialog) -> Result<Self, HRESULT> {
+                let mut res_items: *mut IShellItemArray = ptr::null_mut();
+                (*(item_array.0 as *mut IFileOpenDialog))
+                    .GetResults(&mut res_items)
+                    .check()?;
+
+                let items = &*res_items;
+                let mut count = 0;
+                items.GetCount(&mut count);
+
+                Self { items, count }
+            }
+        }
+
+        impl Iterator for FileList {
+            type Item = *mut IShellItem;
 
-            let items = &*res_items;
-            let mut count = 0;
-            items.GetCount(&mut count);
-            let mut paths = Vec::new();
-            for id in 0..count {
+            fn next(&mut self) -> Option<PathBuf> {
                 let mut res_item: *mut IShellItem = ptr::null_mut();
-                items.GetItemAt(id, &mut res_item).check()?;
+                items.GetItemAt(id, &mut res_item).check().ok()?;
                 let mut display_name: LPWSTR = ptr::null_mut();
                 (*res_item)
                     .GetDisplayName(SIGDN_FILESYSPATH, &mut display_name)
-                    .check()?;
+                    .check()
+                    .ok()?;
                 let filename = to_os_string(&display_name);
                 CoTaskMemFree(display_name as LPVOID);
-                let path = PathBuf::from(filename);
-                paths.push(path);
+                Some(PathBuf::from(filename))
             }
-            items.Release();
+        }
 
-            Ok(paths)
+        impl Drop for FileList {
+            fn drop(&mut self) {
+                self.items.Release();
+            }
         }
+
+        FileList::new(self.0)?
+    }
+
+    pub fn get_results(&self) -> Result<Vec<PathBuf>, HRESULT> {
+        get_results_iter()?.collect()
     }
 
     pub fn get_result(&self) -> Result<PathBuf, HRESULT> {