Merge pull request #2 from AronParker/estimate_max_mem_usage

Add compress_estimate_max_mem_usage

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "brotlic"
-version = "0.8.0"
+version = "0.8.1"
 edition = "2021"
 authors = ["Aron Parker <[email protected]>", "The Brotli Authors"]
 description = """

brotlic-sys/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "brotlic-sys"
-version = "0.2.0"
+version = "0.2.1"
 edition = "2021"
 authors = ["Aron Parker <[email protected]>"]
 description = """

brotlic-sys/build.rs

@@ -41,6 +41,7 @@ fn main() {
         ])
         .include("brotli/c/include")
         .define("BROTLI_BUILD_ENC_EXTRA_API", None)
+        .define("BROTLI_HAVE_LOG2", "1")
         .warnings(false)
         .compile("brotli");
 

src/lib.rs

@@ -920,6 +920,22 @@ pub fn compress_bound(input_size: usize, quality: Quality) -> Option<usize> {
     }
 }
 
+/// Returns peak memory usage for a given quality and window size
+///
+/// Given an input of `input_size` bytes in size, a `quality` and a
+/// `window_size`, estimate the peak memory usage in bytes, not counting the
+/// memory needed for the input and output.
+#[doc(alias = "BrotliEncoderEstimatePeakMemoryUsage")]
+pub fn compress_estimate_max_mem_usage(
+    input_size: usize,
+    quality: Quality,
+    window_size: impl Into<LargeWindowSize>,
+) -> usize {
+    unsafe {
+        BrotliEncoderEstimatePeakMemoryUsage(quality.0 as _, window_size.into().0 as _, input_size)
+    }
+}
+
 /// Read all bytes from `input` and decompress them into `output`, returning how
 /// many bytes were written.
 ///

tests/memory.rs

@@ -1,4 +1,4 @@
-use brotlic::{CompressionMode, Quality, WindowSize};
+use brotlic::{CompressionMode, LargeWindowSize, Quality, WindowSize};
 
 mod common;
 
@@ -72,3 +72,24 @@ fn test_medium_entropy_large() {
 fn test_max_entropy_large() {
     verify(common::gen_max_entropy(8192).as_slice());
 }
+
+#[test]
+fn test_encoder_estimate_peak_memory_usage() {
+    let usage100 =
+        brotlic::compress_estimate_max_mem_usage(100, Quality::best(), WindowSize::best());
+
+    assert!(usage100 > 0);
+}
+
+#[test]
+fn test_google_brotli_issue_1001() {
+    let window_size =
+        brotlic::compress_estimate_max_mem_usage(1024 * 1024, Quality::best(), WindowSize::best());
+    let large_window_size = brotlic::compress_estimate_max_mem_usage(
+        1024 * 1024,
+        Quality::best(),
+        LargeWindowSize::best(),
+    );
+
+    assert!(large_window_size > window_size);
+}