Merge pull request #176 from fintelia/zero-size

Return an error for zero-size images

src/decoder/image.rs

@@ -97,6 +97,11 @@ impl Image {
 
         let width = tag_reader.require_tag(Tag::ImageWidth)?.into_u32()?;
         let height = tag_reader.require_tag(Tag::ImageLength)?.into_u32()?;
+        if width == 0 || height == 0 {
+            return Err(TiffError::FormatError(TiffFormatError::InvalidDimensions(
+                width, height,
+            )));
+        }
 
         let photometric_interpretation = tag_reader
             .find_tag(Tag::PhotometricInterpretation)?

src/encoder/mod.rs

@@ -13,6 +13,7 @@ use std::{
 use crate::{
     error::TiffResult,
     tags::{CompressionMethod, ResolutionUnit, Tag},
+    TiffError, TiffFormatError,
 };
 
 pub mod colortype;
@@ -349,6 +350,12 @@ impl<'a, W: 'a + Write + Seek, T: ColorType, K: TiffKind, D: Compression>
         height: u32,
         compression: D,
     ) -> TiffResult<Self> {
+        if width == 0 || height == 0 {
+            return Err(TiffError::FormatError(TiffFormatError::InvalidDimensions(
+                width, height,
+            )));
+        }
+
         let row_samples = u64::from(width) * u64::try_from(<T>::BITS_PER_SAMPLE.len())?;
         let row_bytes = row_samples * u64::from(<T::Inner>::BYTE_LEN);
 

src/error.rs

@@ -56,6 +56,7 @@ pub enum TiffFormatError {
         actual_samples: usize,
         required_samples: usize,
     },
+    InvalidDimensions(u32, u32),
     InvalidTag,
     InvalidTagValueType(Tag),
     RequiredTagNotFound(Tag),
@@ -100,6 +101,7 @@ impl fmt::Display for TiffFormatError {
                     actual_samples, required_samples
                 )
             }
+            InvalidDimensions(width, height) => write!(fmt, "Invalid dimensions: {}x{}.", width, height),
             InvalidTag => write!(fmt, "Image contains invalid tag."),
             InvalidTagValueType(ref tag) => {
                 write!(fmt, "Tag `{:?}` did not have the expected value type.", tag)