yay capturing works

.gdb_history

@@ -1,3 +0,0 @@
-run
-run -o shiet.png fullscreen
-bt

Cargo.lock

@@ -1,3 +1,8 @@
+[[package]]
+name = "adler32"
+version = "1.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "ansi_term"
 version = "0.11.0"
@@ -42,6 +47,11 @@ name = "bitflags"
 version = "1.0.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "byteorder"
+version = "1.2.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "cc"
 version = "1.0.15"
@@ -66,6 +76,15 @@ dependencies = [
  "vec_map 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "deflate"
+version = "0.7.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "adler32 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "byteorder 1.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "failure"
 version = "0.1.1"
@@ -85,16 +104,57 @@ dependencies = [
  "synstructure 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "inflate"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "adler32 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "libc"
 version = "0.2.40"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "num-integer"
+version = "0.1.39"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "num-traits 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "num-iter"
+version = "0.1.37"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "num-integer 0.1.39 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num-traits 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "num-traits"
+version = "0.2.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "pkg-config"
 version = "0.3.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "png"
+version = "0.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "bitflags 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "deflate 0.7.18 (registry+https://github.com/rust-lang/crates.io-index)",
+ "inflate 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num-iter 0.1.37 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "proc-macro2"
 version = "0.4.19"
@@ -139,6 +199,8 @@ name = "screenshot"
 version = "0.3.0"
 dependencies = [
  "failure 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.40 (registry+https://github.com/rust-lang/crates.io-index)",
+ "png 0.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "structopt 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "time 0.1.40 (registry+https://github.com/rust-lang/crates.io-index)",
  "x11 2.18.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -282,18 +344,26 @@ dependencies = [
 ]
 
 [metadata]
+"checksum adler32 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "7e522997b529f05601e05166c07ed17789691f562762c7f3b987263d2dedee5c"
 "checksum ansi_term 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ee49baf6cb617b853aa8d93bf420db2383fab46d314482ca2803b40d5fde979b"
 "checksum atty 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)" = "2fc4a1aa4c24c0718a250f0681885c1af91419d242f29eb8f2ab28502d80dbd1"
 "checksum backtrace 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)" = "8ea58cd16fd6c9d120b5bcb01d63883ae4cc7ba2aed35c1841b862a3c7ef6639"
 "checksum backtrace-sys 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)" = "44585761d6161b0f57afc49482ab6bd067e4edef48c12a152c237eb0203f7661"
 "checksum bitflags 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "d0c54bb8f454c567f21197eefcdbf5679d0bd99f2ddbe52e84c77061952e6789"
+"checksum byteorder 1.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "90492c5858dd7d2e78691cfb89f90d273a2800fc11d98f60786e5d87e2f83781"
 "checksum cc 1.0.15 (registry+https://github.com/rust-lang/crates.io-index)" = "0ebb87d1116151416c0cf66a0e3fb6430cccd120fd6300794b4dfaa050ac40ba"
 "checksum cfg-if 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "405216fd8fe65f718daa7102ea808a946b6ce40c742998fbfd3463645552de18"
 "checksum clap 2.31.2 (registry+https://github.com/rust-lang/crates.io-index)" = "f0f16b89cbb9ee36d87483dc939fe9f1e13c05898d56d7b230a0d4dff033a536"
+"checksum deflate 0.7.18 (registry+https://github.com/rust-lang/crates.io-index)" = "32c8120d981901a9970a3a1c97cf8b630e0fa8c3ca31e75b6fd6fd5f9f427b31"
 "checksum failure 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "934799b6c1de475a012a02dab0ace1ace43789ee4b99bcfbf1a2e3e8ced5de82"
 "checksum failure_derive 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "c7cdda555bb90c9bb67a3b670a0f42de8e73f5981524123ad8578aafec8ddb8b"
+"checksum inflate 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)" = "6f53b811ee8e2057ccf9643ca6b4277de90efaf5e61e55fd5254576926bb4245"
 "checksum libc 0.2.40 (registry+https://github.com/rust-lang/crates.io-index)" = "6fd41f331ac7c5b8ac259b8bf82c75c0fb2e469bbf37d2becbba9a6a2221965b"
+"checksum num-integer 0.1.39 (registry+https://github.com/rust-lang/crates.io-index)" = "e83d528d2677f0518c570baf2b7abdcf0cd2d248860b68507bdcb3e91d4c0cea"
+"checksum num-iter 0.1.37 (registry+https://github.com/rust-lang/crates.io-index)" = "af3fdbbc3291a5464dc57b03860ec37ca6bf915ed6ee385e7c6c052c422b2124"
+"checksum num-traits 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)" = "630de1ef5cc79d0cdd78b7e33b81f083cbfe90de0f4b2b2f07f905867c70e9fe"
 "checksum pkg-config 0.3.11 (registry+https://github.com/rust-lang/crates.io-index)" = "110d5ee3593dbb73f56294327fe5668bcc997897097cbc76b51e7aed3f52452f"
+"checksum png 0.12.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f54b9600d584d3b8a739e1662a595fab051329eff43f20e7d8cc22872962145b"
 "checksum proc-macro2 0.4.19 (registry+https://github.com/rust-lang/crates.io-index)" = "ffe022fb8c8bd254524b0b3305906c1921fa37a84a644e29079a9e62200c3901"
 "checksum quote 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6e920b65c65f10b2ae65c831a81a073a89edd28c7cce89475bff467ab4167a"
 "checksum quote 0.6.8 (registry+https://github.com/rust-lang/crates.io-index)" = "dd636425967c33af890042c483632d33fa7a18f19ad1d7ea72e8998c6ef8dea5"

Cargo.toml

@@ -9,6 +9,8 @@ crate-type = ["dylib", "rlib"]
 
 [dependencies]
 failure = "0.1"
+png = "0.12"
+libc = "0.2"
 structopt = "0.2"
 time = "0.1"
 x11 = { version = "2.18", features = ["xlib"] }

src/capture.rs

@@ -5,16 +5,16 @@ use image::Image;
 use options::{Options, Region};
 
 pub fn capture(opt: &Options) -> Result<Image, ScreenshotError> {
-    let gui = GUI::new();
+    let gui = GUI::new()?;
 
     let window_to_capture = match opt.region {
         Region::Fullscreen | Region::Selection => gui.get_root_window(),
         Region::ActiveWindow => gui.get_active_window(),
     };
-    println!("Got window_to_capture: {:?}", window_to_capture);
+    println!("capturing window: {}", window_to_capture);
 
     let mut capture = gui.window_capture(window_to_capture)?;
-    println!("Captured the window.");
+    println!("captured the window");
 
     // let final_capture = match opt.region {
     //     Region::Fullscreen | Region::ActiveWindow => window_capture,
@@ -24,7 +24,6 @@ pub fn capture(opt: &Options) -> Result<Image, ScreenshotError> {
     if let Region::Selection = opt.region {
         let region = gui.interactive_select(&capture)?;
         capture.apply_region(&region);
-        println!("Subimaged.");
     };
 
     Ok(capture)

src/errors.rs

@@ -1,5 +1,26 @@
 #[derive(Debug, Fail)]
 pub enum ScreenshotError {
+    #[fail(display = "x11 error: {}", message)]
+    XError { message: String },
+
+    #[fail(display = "io error")]
+    IOError(#[cause] ::std::io::Error),
+
+    #[fail(display = "png encoding error")]
+    PngEncodingError(#[cause] ::png::EncodingError),
+
     #[fail(display = "error")]
     Error,
 }
+
+impl From<::std::io::Error> for ScreenshotError {
+    fn from(err: ::std::io::Error) -> Self {
+        ScreenshotError::IOError(err)
+    }
+}
+
+impl From<::png::EncodingError> for ScreenshotError {
+    fn from(err: ::png::EncodingError) -> Self {
+        ScreenshotError::PngEncodingError(err)
+    }
+}

src/gui.rs

@@ -1,5 +1,6 @@
 use std::ffi::CString;
 
+use libc;
 use x11::xlib::{self, *};
 
 use errors::ScreenshotError;
@@ -11,50 +12,62 @@ pub struct GUI {
 }
 
 impl GUI {
-    pub fn new() -> Self {
+    pub fn new() -> Result<Self, ScreenshotError> {
         let display_str = CString::new(":0").unwrap();
         let display = unsafe { xlib::XOpenDisplay(display_str.as_ptr()) };
+        if display.is_null() {
+            return Err(ScreenshotError::XError {
+                message: format!("failed to open display"),
+            });
+        }
         unsafe { XGrabServer(display) };
-        GUI { display }
+        Ok(GUI { display })
     }
 
-    fn get_window_attributes(&self, window: *mut Window) -> *mut XWindowAttributes {
+    fn get_window_attributes(
-        let attr: *mut XWindowAttributes = unsafe { ::std::mem::uninitialized() };
+        &self,
-        unsafe { XGetWindowAttributes(self.display, *window, attr) };
+        window: Window,
-        attr
+    ) -> Result<*mut XWindowAttributes, ScreenshotError> {
+        let attr_size = ::std::mem::size_of::<XWindowAttributes>();
+        let attr = unsafe { libc::malloc(attr_size) as *mut XWindowAttributes };
+        let result = unsafe { XGetWindowAttributes(self.display, window, attr) };
+        if result == 0 {
+            return Err(ScreenshotError::XError {
+                message: format!("failed to get window attributes"),
+            });
+        }
+        Ok(attr)
     }
 
     /// Captures the window and produces a DynamicImage.
-    pub fn window_capture(&self, window: *mut Window) -> Result<Image, ScreenshotError> {
+    pub fn window_capture(&self, window: Window) -> Result<Image, ScreenshotError> {
-        println!("Getting window attributes.");
+        let attr = self.get_window_attributes(window)?;
-        let attr = unsafe { *self.get_window_attributes(window) };
+        println!("got window attributes");
-        println!("Got window attributes.");
         let image = unsafe {
             xlib::XGetImage(
                 self.display,
-                *window,
+                window,
-                attr.x,
+                (*attr).x,
-                attr.y,
+                (*attr).y,
-                attr.width as u32,
+                (*attr).width as u32,
-                attr.height as u32,
+                (*attr).height as u32,
                 0xffffffff,
                 ZPixmap,
             )
         };
-        Ok(Image::from(image))
+        Ok(Image::from(self.display, image))
     }
 
     /// Get the full screen.
-    pub fn get_root_window(&self) -> *mut Window {
+    pub fn get_root_window(&self) -> Window {
-        println!("Getting root window...");
+        unsafe { xlib::XRootWindow(self.display, 0) as Window }
-        unsafe { xlib::XRootWindow(self.display, 0) as *mut Window }
     }
 
     /// Get the active window.
-    pub fn get_active_window(&self) -> *mut Window {
+    pub fn get_active_window(&self) -> Window {
-        let window: *mut Window = unsafe { ::std::mem::uninitialized() };
+        let mut window: Window = unsafe { ::std::mem::uninitialized() };
         let mut revert_to_return: i32 = unsafe { ::std::mem::uninitialized() };
-        unsafe { xlib::XGetInputFocus(self.display, window, &mut revert_to_return) };
+        unsafe { xlib::XGetInputFocus(self.display, &mut window, &mut revert_to_return) };
         window
     }
 

src/image.rs

@@ -1,15 +1,62 @@
-use x11::xlib::XImage;
+use std::fs::File;
+use std::io::BufWriter;
+use std::path::Path;
 
+use png::{self, Encoder, HasParameters};
+use x11::xlib::*;
+
+use errors::ScreenshotError;
 use Rectangle;
 
+#[allow(dead_code)]
 pub struct Image {
-    _inner: *mut XImage,
+    display: *mut Display,
+    inner: *mut XImage,
 }
 
 impl Image {
-    pub fn from(inner: *mut XImage) -> Self {
+    pub fn from(display: *mut Display, inner: *mut XImage) -> Self {
-        Image { _inner: inner }
+        Image { inner, display }
     }
 
     pub fn apply_region(&mut self, _region: &Rectangle) {}
+
+    /// Converts the image buffer into RGB(A).
+    fn to_data_buf(&self) -> Vec<u8> {
+        let im = unsafe { *self.inner };
+        let size = 4usize * im.width as usize * im.height as usize;
+        let mut buf = vec![1; size];
+        let sbuf = unsafe { ::std::slice::from_raw_parts(im.data, size) }; // source buffer
+        let mut sx = 0usize; // source idx
+        let mut dx = 0usize; // dest idx
+        if im.byte_order == LSBFirst {
+            while dx < size {
+                buf[dx] = sbuf[sx + 2] as u8;
+                buf[dx + 1] = sbuf[sx + 1] as u8;
+                buf[dx + 2] = sbuf[sx] as u8;
+                buf[dx + 3] = if im.depth == 32 {
+                    sbuf[sx + 3] as u8
+                } else {
+                    255u8
+                };
+                sx += 4;
+                dx += 4;
+            }
+        }
+        buf
+    }
+
+    pub fn write_png(&self, out: impl AsRef<Path>) -> Result<(), ScreenshotError> {
+        let file = File::create(out.as_ref())?;
+        let ref mut out = BufWriter::new(file);
+
+        let (width, height) = unsafe { ((*self.inner).width as u32, (*self.inner).height as u32) };
+        let mut encoder = Encoder::new(out, width, height);
+        encoder.set(png::ColorType::RGBA).set(png::BitDepth::Eight);
+        let mut writer = encoder.write_header()?;
+
+        let data = self.to_data_buf();
+        writer.write_image_data(data.as_slice())?;
+        Ok(())
+    }
 }

src/lib.rs

@@ -1,5 +1,7 @@
 #[macro_use]
 extern crate failure;
+extern crate libc;
+extern crate png;
 #[macro_use]
 extern crate structopt;
 extern crate time;
@@ -11,10 +13,10 @@ mod gui;
 mod image;
 mod options;
 
-use failure::Error;
 use structopt::StructOpt;
 
-use options::Options;
+pub use capture::capture;
+pub use options::Options;
 
 pub struct Rectangle {
     pub x: u32,
@@ -22,9 +24,3 @@ pub struct Rectangle {
     pub width: u32,
     pub height: u32,
 }
-
-pub fn run() -> Result<(), Error> {
-    let opt = Options::from_args();
-    capture::capture(&opt)?;
-    Ok(())
-}

src/main.rs

@@ -1,13 +1,13 @@
+extern crate failure;
 extern crate screenshot;
+extern crate structopt;
 
-use std::process::exit;
+use failure::Error;
+use screenshot::{capture, Options};
+use structopt::StructOpt;
 
-fn main() {
+pub fn main() -> Result<(), Error> {
-    match screenshot::run() {
+    let opt = Options::from_args();
-        Ok(()) => (),
+    let image = capture(&opt)?;
-        Err(error) => {
+    image.write_png(opt.outfile).map_err(|err| err.into())
-            eprintln!("Error: {}", error);
-            exit(1);
-        }
-    }
 }