Initial project import

tools/v/vlib/compress/gzip/gzip.v

@@ -0,0 +1,98 @@
+// [rfc1952](https://datatracker.ietf.org/doc/html/rfc1952) compliant
+// gzip compression/decompression
+
+module gzip
+
+import compress.deflate
+
+// CompressFlags
+@[deprecated: 'never used']
+@[deprecated_after: '2026-07-31']
+@[flag]
+pub enum CompressFlags {
+	// The low 12 bits will be overwritten by `compression_level`
+	compression_level_overwrite_flag01
+	compression_level_overwrite_flag02
+	compression_level_overwrite_flag03
+	compression_level_overwrite_flag04
+	compression_level_overwrite_flag05
+	compression_level_overwrite_flag06
+	compression_level_overwrite_flag07
+	compression_level_overwrite_flag08
+	compression_level_overwrite_flag09
+	compression_level_overwrite_flag10
+	compression_level_overwrite_flag11
+	compression_level_overwrite_flag12
+	write_zlib_header
+	compute_adler32
+	greedy_parsing_flag
+	nondeterministic_parsing_flag
+	rle_matches
+	filter_matches
+	force_all_static_blocks
+	force_all_raw_blocks
+}
+
+// CompressParams set compression_level for compression:
+@[deprecated: 'never used']
+@[deprecated_after: '2026-07-31']
+@[params]
+pub struct CompressParams {
+pub:
+	compression_level int
+	flags             CompressFlags
+}
+
+// compress compresses an array of bytes using gzip and returns the compressed bytes in a new array.
+pub fn compress(data []u8) ![]u8 {
+	// Delegate to deflate.compress_gzip() which implements RFC 1952
+	return deflate.compress_gzip(data)
+}
+
+// DecompressFlags
+// N.B.: only retained for API compatibility.
+@[deprecated: 'never used']
+@[deprecated_after: '2026-07-31']
+@[flag]
+pub enum DecompressFlags {
+	parse_zlib_header
+	has_more_input
+	using_non_wrapping_output_buf
+	compute_adler32
+}
+
+// DecompressParams controls gzip decompression behavior.
+// N.B.: only retained for API compatibility.
+@[deprecated: 'never used']
+@[deprecated_after: '2026-07-31']
+@[params]
+pub struct DecompressParams {
+pub:
+	verify_header_checksum bool = true
+	verify_length          bool = true
+	verify_checksum        bool = true
+	flags                  DecompressFlags
+}
+
+// validate validates the gzip header of data and returns its parsed details if valid.
+// N.B.: only retained for API compatibility, all validation is now performed by the deflate backend.
+// The returned header details are not used by the decompressor.
+// TODO: remove after the deprecation period.
+@[deprecated: 'never used']
+@[deprecated_after: '2026-07-31']
+pub fn validate(data []u8, _ DecompressParams) !deflate.GzipHeader {
+	return deflate.validate_gzip_header(data)!
+}
+
+// decompress decompresses a gzip stream and returns the decompressed bytes in a new array.
+pub fn decompress(data []u8) ![]u8 {
+	return deflate.decompress_gzip(data)
+}
+
+// decompress_with_callback decompresses a gzip stream (RFC 1952) using a callback for chunked delivery.
+// The callback receives chunks of decompressed data and should return the chunk length to continue, or 0 to abort.
+// Returns the total decompressed length.
+pub fn decompress_with_callback(data []u8, cb deflate.ChunkCallback, userdata voidptr) !int {
+	deflate.validate_gzip_header(data)!
+	return deflate.decompress_with_callback(data, cb, userdata)
+}