add gx_dvb extractor

README.md

@@ -71,6 +71,10 @@ Options:
 **Used in:** Funai & Funai-made Philips TVs (USA market)  
 **Notes:** **Depends on keys** - see keys.rs (most common keys should be included).    
 
+## GX DVB
+**Used in:** Cheap NationalChip GX-based DVB tuners    
+**Notes:** None, all files should be supported
+
 ## INVINCIBLE_IMAGE   
 **Used in:** LG Broadcom-based Blu-Ray players  
 **Notes:** Only version 3 is supported (2011+)    

src/formats.rs

@@ -29,6 +29,7 @@ pub mod amlogic;
 pub mod sdboot;
 pub mod sdimage;
 pub mod cd5;
+pub mod gx_dvb;
 
 pub mod pup;
 
@@ -220,6 +221,11 @@ pub fn get_registry() -> Vec<Format> {
             detector_func: crate::formats::cd5::is_cd5_file,
             extractor_func: crate::formats::cd5::extract_cd5,
         },
+        Format {
+            name: "gx_dvb",
+            detector_func: crate::formats::gx_dvb::is_gx_dvb_file,
+            extractor_func: crate::formats::gx_dvb::extract_gx_dvb,
+        },
 
     ]
 }

src/formats/gx_dvb/include.rs

@@ -0,0 +1,25 @@
+use crate::utils::common;
+use binrw::BinRead;
+
+pub static TABLE_OFFSET: u64 = 0x20000;
+
+#[derive(BinRead)]
+pub struct PartTable {
+    _magic_bytes: [u8;4],
+    pub part_count: u8,
+    #[br(count=part_count)] pub part_entries: Vec<PartEntry>,
+}
+
+#[derive(BinRead)]
+pub struct PartEntry {
+    name_bytes: [u8; 8],
+    pub total_size: u32,
+    pub used_size: u32,
+    pub start: u32,         //offset
+    _flags: u32,
+}
+impl PartEntry {
+    pub fn name(&self) -> String {
+        common::string_from_bytes(&self.name_bytes)
+    }
+}

src/formats/gx_dvb/mod.rs

@@ -0,0 +1,46 @@
+mod include;
+use std::any::Any;
+use std::fs::{self, OpenOptions};
+use std::io::{Seek, SeekFrom, Write};
+use std::path::Path;
+use crate::AppContext;
+
+use crate::utils::common;
+use binrw::BinReaderExt;
+use include::*;
+
+pub fn is_gx_dvb_file(app_ctx: &AppContext) -> Result<Option<Box<dyn Any>>, Box<dyn std::error::Error>> {
+    let file = match app_ctx.file() {Some(f) => f, None => return Ok(None)};
+
+    let table_magic = common::read_file(&file, TABLE_OFFSET, 4)?;
+    if table_magic == b"\xAA\xBC\xDE\xFA" {
+        Ok(Some(Box::new(())))
+    } else {
+        Ok(None)
+    }
+}
+
+pub fn extract_gx_dvb(app_ctx: &AppContext, _ctx: Box<dyn Any>) -> Result<(), Box<dyn std::error::Error>> {
+    let mut file = app_ctx.file().ok_or("Extractor expected file")?;    
+
+    file.seek(SeekFrom::Start(TABLE_OFFSET))?;
+    let table: PartTable = file.read_be()?;
+
+    println!("Part count: {}", table.part_count);
+
+    for (i, part) in table.part_entries.iter().enumerate() {
+        println!("\n({}/{}) - {}, Offset: {}, Total size: {}, Used size: {}",
+                i+1, table.part_count, part.name(), part.start, part.total_size, part.used_size);
+
+        let data = common::read_file(&file, part.start as u64, part.total_size as usize)?;
+
+        let output_path = Path::new(&app_ctx.output_dir).join(format!("{}.bin", part.name()));
+        fs::create_dir_all(&app_ctx.output_dir)?;
+        let mut out_file = OpenOptions::new().write(true).create(true).open(output_path)?;        
+        out_file.write_all(&data)?;
+
+        println!("- Saved file!");
+    }
+
+    Ok(())
+}