[WIP] [FIX] #1499 Persistent Dtvcc struct for CEA-708 decoding in Rust

.gitignore

@@ -44,6 +44,7 @@ windows/.vs/**
 *.opendb
 *.db
 *.vscode
+.cache
 
 ####
 # Ignore the header file that is updated upon build
@@ -153,4 +154,4 @@ src/rust/target/
 windows/ccx_rust.lib
 windows/*/debug/*
 windows/*/CACHEDIR.TAG
-windows/.rustc_info.json
+windows/.rustc_info.json

src/lib_ccx/ccx_decoders_common.c

@@ -18,6 +18,8 @@ made to reuse, not duplicate, as many functions as possible */
 #ifndef DISABLE_RUST
 extern int ccxr_process_cc_data(struct lib_cc_decode *dec_ctx, unsigned char *cc_data, int cc_count);
 extern void ccxr_flush_decoder(struct dtvcc_ctx *dtvcc, struct dtvcc_service_decoder *decoder);
+extern void *ccxr_dtvcc_init(struct ccx_decoder_dtvcc_settings *settings_dtvcc);
+extern void ccxr_dtvcc_free(void *dtvcc_rust);
 #endif
 
 uint64_t utc_refvalue = UINT64_MAX; /* _UI64_MAX/UINT64_MAX means don't use UNIX, 0 = use current system time as reference, +1 use a specific reference */
@@ -232,6 +234,9 @@ int do_cb(struct lib_cc_decode *ctx, unsigned char *cc_block, struct cc_subtitle
 void dinit_cc_decode(struct lib_cc_decode **ctx)
 {
 	struct lib_cc_decode *lctx = *ctx;
+#ifndef DISABLE_RUST
+	ccxr_dtvcc_free(lctx->dtvcc_rust);
+#endif
 	dtvcc_free(&lctx->dtvcc);
 	dinit_avc(&lctx->avc_ctx);
 	ccx_decoder_608_dinit_library(&lctx->context_cc608_field_1);
@@ -261,6 +266,9 @@ struct lib_cc_decode *init_cc_decode(struct ccx_decoders_common_settings_t *sett
 	ctx->no_rollup = setting->no_rollup;
 	ctx->noscte20 = setting->noscte20;
 
+#ifndef DISABLE_RUST
+	ctx->dtvcc_rust = ccxr_dtvcc_init(setting->settings_dtvcc);
+#endif
 	ctx->dtvcc = dtvcc_init(setting->settings_dtvcc);
 	ctx->dtvcc->is_active = setting->settings_dtvcc->enabled;
 

src/lib_ccx/ccx_decoders_structs.h

@@ -208,6 +208,7 @@ struct lib_cc_decode
     int stat_divicom;
     int false_pict_header;
 
+    	void *dtvcc_rust;
 	dtvcc_ctx *dtvcc;
 	int current_field;
 	// Analyse/use the picture information

src/lib_ccx/general_loop.c

@@ -18,6 +18,10 @@
 #include "dvd_subtitle_decoder.h"
 #include "ccx_demuxer_mxf.h"
 
+#ifndef DISABLE_RUST
+extern void ccxr_dtvcc_set_encoder(void *dtvcc_rust, void *encoder);
+#endif
+
 int end_of_file = 0; // End of file?
 
 // Program stream specific data grabber
@@ -896,7 +900,11 @@ int process_non_multiprogram_general_loop(struct lib_ccx_ctx *ctx,
 	cinfo = get_cinfo(ctx->demux_ctx, pid);
 	*enc_ctx = update_encoder_list_cinfo(ctx, cinfo);
 	*dec_ctx = update_decoder_list_cinfo(ctx, cinfo);
+#ifdef DISABLE_RUST
 	(*dec_ctx)->dtvcc->encoder = (void *)(*enc_ctx);
+#else
+	ccxr_dtvcc_set_encoder((*dec_ctx)->dtvcc_rust, *enc_ctx);
+#endif
 
 	if ((*dec_ctx)->timing->min_pts == 0x01FFFFFFFFLL) // if we didn't set the min_pts of the program
 	{
@@ -1093,7 +1101,11 @@ int general_loop(struct lib_ccx_ctx *ctx)
 
 				enc_ctx = update_encoder_list_cinfo(ctx, cinfo);
 				dec_ctx = update_decoder_list_cinfo(ctx, cinfo);
+#ifdef DISABLE_RUST
 				dec_ctx->dtvcc->encoder = (void *)enc_ctx; // WARN: otherwise cea-708 will not work
+#else
+				ccxr_dtvcc_set_encoder(dec_ctx->dtvcc_rust, (void *)enc_ctx);
+#endif
 
 				if (dec_ctx->timing->min_pts == 0x01FFFFFFFFLL) // if we didn't set the min_pts of the program
 				{
@@ -1268,7 +1280,11 @@ int rcwt_loop(struct lib_ccx_ctx *ctx)
 	}
 
 	dec_ctx = update_decoder_list(ctx);
+#ifdef DISABLE_RUST
 	dec_ctx->dtvcc->encoder = (void *)enc_ctx; // WARN: otherwise cea-708 will not work
+#else
+	ccxr_dtvcc_set_encoder(dec_ctx->dtvcc_rust, (void *)enc_ctx);
+#endif
 	if (parsebuf[6] == 0 && parsebuf[7] == 2)
 	{
 		dec_ctx->codec = CCX_CODEC_TELETEXT;

src/lib_ccx/mp4.c

@@ -16,6 +16,11 @@
 
 #define GF_ISOM_SUBTYPE_C708 GF_4CC('c', '7', '0', '8')
 
+#ifndef DISABLE_RUST
+extern void ccxr_process_data(void *dtvcc_rust, unsigned char cc_valid, unsigned char cc_char, unsigned char data1, unsigned char data2);
+extern void ccxr_dtvcc_set_encoder(void *dtvcc_rust, void *encoder);
+#endif
+
 static short bswap16(short v)
 {
 	return ((v >> 8) & 0x00FF) | ((v << 8) & 0xFF00);
@@ -394,8 +399,13 @@ static int process_clcp(struct lib_ccx_ctx *ctx, struct encoder_ctx *enc_ctx,
 					continue;
 				}
 				// WARN: otherwise cea-708 will not work
+#ifdef DISABLE_RUST
 				dec_ctx->dtvcc->encoder = (void *)enc_ctx;
 				dtvcc_process_data(dec_ctx->dtvcc, (unsigned char *)temp);
+#else
+				ccxr_dtvcc_set_encoder(dec_ctx->dtvcc_rust, (void *)enc_ctx);
+				ccxr_process_data(dec_ctx->dtvcc_rust, cc_valid, cc_type, cc_data[1], cc_data[2]);
+#endif
 				cb_708++;
 			}
 			if (ctx->write_format == CCX_OF_MCC)

src/rust/build.rs

@@ -59,6 +59,7 @@ fn main() {
     }
 
     let bindings = builder
+        .derive_default(true)
         // Finish the builder and generate the bindings.
         .generate()
         // Unwrap the Result and panic on failure.

src/rust/src/decoder/mod.rs

@@ -9,7 +9,10 @@ mod timing;
 mod tv_screen;
 mod window;
 
-use crate::{bindings::*, utils::is_true};
+use crate::{
+    bindings::*,
+    utils::{is_false, is_true},
+};
 
 use log::{debug, warn};
 
@@ -19,47 +22,107 @@ const CCX_DTVCC_SCREENGRID_ROWS: u8 = 75;
 const CCX_DTVCC_SCREENGRID_COLUMNS: u8 = 210;
 const CCX_DTVCC_MAX_ROWS: u8 = 15;
 const CCX_DTVCC_MAX_COLUMNS: u8 = 32 * 2;
+const CCX_DTVCC_MAX_SERVICES: usize = 63;
+// const CCX_DTVCC_MAX_WINDOWS: usize = 8;
 
 /// Context required for processing 708 data
-pub struct Dtvcc<'a> {
+pub struct Dtvcc {
     pub is_active: bool,
     pub active_services_count: u8,
-    pub services_active: Vec<i32>,
+    pub services_active: [i32; CCX_DTVCC_MAX_SERVICES],
     pub report_enabled: bool,
-    pub report: &'a mut ccx_decoder_dtvcc_report,
-    pub decoders: Vec<&'a mut dtvcc_service_decoder>,
-    pub packet: Vec<u8>,
+    pub report: *mut ccx_decoder_dtvcc_report,
+    pub decoders: [Option<Box<dtvcc_service_decoder>>; CCX_DTVCC_MAX_SERVICES],
+    pub packet: [u8; CCX_DTVCC_MAX_SERVICES],
     pub packet_length: u8,
     pub is_header_parsed: bool,
     pub last_sequence: i32,
-    pub encoder: &'a mut encoder_ctx,
+    pub encoder: *mut encoder_ctx,
     pub no_rollup: bool,
-    pub timing: &'a mut ccx_common_timing_ctx,
+    pub timing: *mut ccx_common_timing_ctx,
 }
 
-impl<'a> Dtvcc<'a> {
+impl Dtvcc {
     /// Create a new dtvcc context
-    pub fn new(ctx: &'a mut dtvcc_ctx) -> Self {
-        let report = unsafe { &mut *ctx.report };
-        let encoder = unsafe { &mut *(ctx.encoder as *mut encoder_ctx) };
-        let timing = unsafe { &mut *ctx.timing };
+    pub fn new(opts: &ccx_decoder_dtvcc_settings) -> Self {
+        // closely follows `dtvcc_init` at `src/lib_ccx/ccx_dtvcc.c:76`
+
+        let report = opts.report;
+        unsafe {
+            (*report).reset_count = 0;
+        }
+
+        let is_active = false;
+        let no_rollup = is_true(opts.no_rollup);
+        let active_services_count = opts.active_services_count as u8;
+        let services_active = opts.services_enabled;
+
+        // `dtvcc_clear_packet` does the following
+        let packet_length = 0;
+        let is_header_parsed = false;
+        let packet = [0; CCX_DTVCC_MAX_SERVICES]; // unlike C, packet is allocated on the stack
+
+        let last_sequence = CCX_DTVCC_NO_LAST_SEQUENCE;
+
+        let report_enabled = is_true(opts.print_file_reports);
+        let timing = opts.timing;
+
+        // unlike C, here the decoders are allocated on the stack as an array.
+        let decoders = {
+            const INIT: Option<Box<dtvcc_service_decoder>> = None;
+            let mut decoders = [INIT; CCX_DTVCC_MAX_SERVICES];
+
+            decoders
+                .iter_mut()
+                .zip(opts.services_enabled)
+                .enumerate()
+                .for_each(|(i, (d, se))| {
+                    if is_false(se) {
+                        return;
+                    }
+
+                    let mut decoder = Box::new(dtvcc_service_decoder {
+                        // we cannot allocate this on the stack as `dtvcc_service_decoder` is a C
+                        // struct cannot be changed trivially
+                        tv: Box::into_raw(Box::new(dtvcc_tv_screen {
+                            cc_count: 0,
+                            service_number: i as i32 + 1,
+                            ..dtvcc_tv_screen::default()
+                        })),
+                        ..dtvcc_service_decoder::default()
+                    });
+
+                    decoder.windows.iter_mut().for_each(|w| {
+                        w.memory_reserved = 0;
+                    });
+
+                    unsafe { dtvcc_windows_reset(decoder.as_mut()) };
+
+                    *d = Some(decoder);
+                });
+
+            decoders
+        };
+
+        let encoder = std::ptr::null_mut(); // Unlike C, does not mention `encoder` and is initialised to `null` by default
 
         Self {
-            is_active: is_true(ctx.is_active),
-            active_services_count: ctx.active_services_count as u8,
-            services_active: ctx.services_active.to_vec(),
-            report_enabled: is_true(ctx.report_enabled),
             report,
-            decoders: ctx.decoders.iter_mut().collect(),
-            packet: ctx.current_packet.to_vec(),
-            packet_length: ctx.current_packet_length as u8,
-            is_header_parsed: is_true(ctx.is_current_packet_header_parsed),
-            last_sequence: ctx.last_sequence,
-            encoder,
-            no_rollup: is_true(ctx.no_rollup),
+            is_active,
+            no_rollup,
+            active_services_count,
+            services_active,
+            packet_length,
+            is_header_parsed,
+            packet,
+            last_sequence,
+            report_enabled,
             timing,
+            decoders,
+            encoder,
         }
     }
+
     /// Process cc data and add it to the dtvcc packet
     pub fn process_cc_data(&mut self, cc_valid: u8, cc_type: u8, data1: u8, data2: u8) {
         if !self.is_active && !self.report_enabled {
@@ -166,15 +229,15 @@ impl<'a> Dtvcc<'a> {
             }
 
             if block_length != 0 {
-                self.report.services[service_number as usize] = 1;
+                unsafe { (*self.report).services[service_number as usize] = 1 };
             }
 
             if service_number > 0 && is_true(self.services_active[(service_number - 1) as usize]) {
                 let decoder = &mut self.decoders[(service_number - 1) as usize];
-                decoder.process_service_block(
+                decoder.as_mut().unwrap().process_service_block(
                     &self.packet[pos as usize..(pos + block_length) as usize],
-                    self.encoder,
-                    self.timing,
+                    unsafe { self.encoder.as_mut().unwrap() },
+                    unsafe { self.timing.as_mut().unwrap() },
                     self.no_rollup,
                 );
             }
@@ -197,6 +260,33 @@ impl<'a> Dtvcc<'a> {
     }
 }
 
+impl Drop for Dtvcc {
+    fn drop(&mut self) {
+        // closely follows `dtvcc_free` at `src/lib_ccx/ccx_dtvcc.c:126`
+        for i in 0..CCX_DTVCC_MAX_SERVICES {
+            if let Some(decoder) = self.decoders[i].as_mut() {
+                if !is_true(self.services_active[i]) {
+                    continue;
+                }
+
+                decoder.windows.iter_mut().for_each(|window| {
+                    if is_false(window.memory_reserved) {
+                        return;
+                    }
+
+                    window.rows.iter().for_each(|symbol_ptr| unsafe {
+                        symbol_ptr.drop_in_place();
+                    });
+
+                    window.memory_reserved = 0;
+                });
+
+                unsafe { decoder.tv.drop_in_place() };
+            }
+        }
+    }
+}
+
 /// A single character symbol
 ///
 /// sym stores the symbol
@@ -216,10 +306,3 @@ impl dtvcc_symbol {
         is_true(self.init)
     }
 }
-
-impl Default for dtvcc_symbol {
-    /// Create a blank uninitialized symbol
-    fn default() -> Self {
-        Self { sym: 0, init: 0 }
-    }
-}

src/rust/src/decoder/tv_screen.rs

@@ -148,8 +148,8 @@ impl dtvcc_tv_screen {
         use_colors: bool,
     ) -> Result<(), String> {
         let mut buf = Vec::new();
-        let mut pen_color = dtvcc_pen_color::default();
-        let mut pen_attribs = dtvcc_pen_attribs::default();
+        let mut pen_color = dtvcc_pen_color::new();
+        let mut pen_attribs = dtvcc_pen_attribs::new();
         let (first, last) = self.get_write_interval(row_index);
         debug!("First: {}, Last: {}", first, last);
 
@@ -418,7 +418,7 @@ impl dtvcc_tv_screen {
             return;
         }
         let new_pen_attribs = if col_index >= CCX_DTVCC_SCREENGRID_COLUMNS as usize {
-            dtvcc_pen_attribs::default()
+            dtvcc_pen_attribs::new()
         } else {
             self.pen_attribs[row_index][col_index]
         };
@@ -455,7 +455,7 @@ impl dtvcc_tv_screen {
             return;
         }
         let new_pen_color = if col_index >= CCX_DTVCC_SCREENGRID_COLUMNS as usize {
-            dtvcc_pen_color::default()
+            dtvcc_pen_color::new()
         } else {
             self.pen_colors[row_index][col_index]
         };