pana_dvd: show gzip file name fix readme

README.md

@@ -106,7 +106,7 @@ Options:
 
 ## Panasonic Blu-Ray (PANA_DVD.FRM, PANA_ESD.FRM, PANAEUSB.FRM)
 **Used in:** Panasonic Blu-Ray Players and Recorders  
-**Notes:** **Depends on keys** - see keys.rs (Included keys should work for 99% of players released in and before 2014, and some released in 2018), Note that there is currently an issue with MAIN in some very ancient files not extracting correctly. 
+**Notes:** **Depends on keys** - see keys.rs (Included keys should work for 99% of players released in and before 2014, and some released in 2018), Note that there is currently an issue with MAIN in some very ancient files not extracting correctly.   
 **Options:**   
 `pana_dvd:split_main` - Automatically split the MAIN module into seperate partitions.
 

src/formats/pana_dvd/mod.rs

@@ -13,7 +13,7 @@ use binrw::BinReaderExt;
 use crate::keys;
 use crate::utils::common;
 use crate::utils::aes::{decrypt_aes128_cbc_nopad};
-use crate::utils::compression::{decompress_gzip};
+use crate::utils::compression::{decompress_gzip_get_filename};
 use pana_dvd_crypto::{decrypt_data};
 use lzss::{decompress_lzss};
 use include::*;
@@ -233,8 +233,10 @@ fn decompress_data(data: &[u8]) -> Result<Vec<u8>, Box<dyn std::error::Error>> {
 
     if header.compression_type == 1 { //gzip + optionally lzss
         println!("- Decompressing GZIP...");
-        let decompressed_gzip = decompress_gzip(&compressed_data)?;
+        let (decompressed_gzip, gzip_filename) = decompress_gzip_get_filename(&compressed_data)?;
-
+        if let Some(gzip_filename) = gzip_filename {
+            println!("- GZIP filename: {}", gzip_filename);
+        }
         // the decompressed data can have another header
         if decompressed_gzip.starts_with(COMPRESSED_FILE_MAGIC) {
             decompressed_data = decompress_data(&decompressed_gzip)?;

src/utils/compression.rs

@@ -7,6 +7,8 @@ use lz4::block::decompress;
 use bzip2::read::BzDecoder;
 use liblzma::read::XzDecoder;
 
+use crate::utils::common;
+
 pub fn decompress_zlib(data: &[u8]) -> io::Result<Vec<u8>> {
     let mut decoder = ZlibDecoder::new(data);
     let mut decompressed = Vec::new();
@@ -22,6 +24,20 @@ pub fn decompress_gzip(compressed_data: &[u8]) -> Result<Vec<u8>, Box<dyn std::e
     Ok(decompressed)
 }
 
+pub fn decompress_gzip_get_filename(compressed_data: &[u8]) -> Result<(Vec<u8>, Option<String>), Box<dyn std::error::Error>> {
+    let mut decoder = GzDecoder::new(compressed_data);
+    
+    let mut filename: Option<String> = None;
+    if let Some(filename_bytes) = decoder.header().unwrap().filename() {
+        filename = Some(common::string_from_bytes(filename_bytes));
+    }
+
+    let mut decompressed = Vec::new();
+    decoder.read_to_end(&mut decompressed)?;
+
+    Ok((decompressed, filename))
+}
+
 pub fn decompress_lzma(compressed_data: &[u8]) -> Result<Vec<u8>, Box<dyn std::error::Error>> {
     let mut input = Cursor::new(compressed_data);
     let mut output = Vec::new();