gdal 0.1.1

GDAL bindings for Rust
Documentation 
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use std::ffi::CString;
use std::path::Path;
use std::ptr::null;
use libc::c_int;
use vector::{ogr, Layer};
use vector::driver::_register_drivers;

/// Vector dataset
///
/// ```
/// use std::path::Path;
/// use gdal::vector::Dataset;
///
/// let mut dataset = Dataset::open(Path::new("fixtures/roads.geojson")).unwrap();
/// println!("Dataset has {} layers", dataset.count());
/// ```
pub struct Dataset {
    c_dataset: *const (),
    layers: Vec<Layer>,
}


impl Dataset {
    pub unsafe fn _with_c_dataset(c_dataset: *const ()) -> Dataset {
        Dataset{c_dataset: c_dataset, layers: vec!()}
    }

    /// Open the dataset at `path`.
    pub fn open(path: &Path) -> Option<Dataset> {
        _register_drivers();
        let filename = path.to_str().unwrap();
        let c_filename = CString::new(filename.as_bytes()).unwrap();
        let c_dataset = unsafe { ogr::OGROpen(c_filename.as_ptr(), 0, null()) };
        return match c_dataset.is_null() {
            true  => None,
            false => Some(Dataset{c_dataset: c_dataset, layers: vec!()}),
        };
    }

    /// Get number of layers.
    pub fn count(&self) -> isize {
        return unsafe { ogr::OGR_DS_GetLayerCount(self.c_dataset) } as isize;
    }

    fn _child_layer(&mut self, c_layer: *const ()) -> &Layer {
        let layer = unsafe { Layer::_with_c_layer(c_layer) };
        self.layers.push(layer);
        return self.layers.last().unwrap();
    }

    /// Get layer number `idx`.
    pub fn layer(&mut self, idx: isize) -> Option<&Layer> {
        let c_layer = unsafe { ogr::OGR_DS_GetLayer(self.c_dataset, idx as c_int) };
        return match c_layer.is_null() {
            true  => None,
            false => Some(self._child_layer(c_layer)),
        };
    }

    /// Create a new layer with a blank definition.
    pub fn create_layer(&mut self) -> &mut Layer {
        let c_name = CString::new("".as_bytes()).unwrap();
        let c_layer = unsafe { ogr::OGR_DS_CreateLayer(
            self.c_dataset,
            c_name.as_ptr(),
            null(),
            ogr::WKB_UNKNOWN,
            null(),
        ) };
        match c_layer.is_null() {
            true  => panic!("Layer creation failed"),
            false => {
                self._child_layer(c_layer);
                return self.layers.last_mut().unwrap();
            }
        };
    }
}


impl Drop for Dataset {
    fn drop(&mut self) {
        unsafe { ogr::OGR_DS_Destroy(self.c_dataset); }
    }
}