feat(rust): Added Encoder Module (#1710)

* Added Encoder Module

* Encoder: Windows Compatibility

* Encoder: C formatting

* Encoder: recommended changes to the encoding module - logic reduction

* Encoder: Minor stylistic change

* Encoder: Review changes, renamed Line21 to Ascii

* Encoder: Slight modification in C version of write_cc_buffer_as_simplexml

* Encoder: Renamed 2 files

* Encoder: Minor Capitalization Change

* Encoder: Review Suggestions

Author: steel-bucket

docs/CHANGES.TXT

@@ -1,5 +1,6 @@
 1.0 (to be released)
 -----------------
+- New: Add Encoder Module to Rust
 - Fix: Elementary stream regressions
 - Fix: Segmentation faults on XDS files
 - Fix: Clippy Errors Based on Rust 1.88

src/lib_ccx/ccx_encoders_common.c

@@ -19,6 +19,10 @@ int fsync(int fd)
 }
 #endif
 
+#ifndef DISABLE_RUST
+int ccxr_get_str_basic(unsigned char *out_buffer, unsigned char *in_buffer, int trim_subs,
+		       enum ccx_encoding_type in_enc, enum ccx_encoding_type out_enc, int max_len);
+#endif
 // These are the default settings for plain transcripts. No times, no CC or caption mode, and no XDS.
 ccx_encoders_transcript_format ccx_encoders_default_transcript_settings =
     {
@@ -293,6 +297,9 @@ int change_ascii_encoding(unsigned char *dest, unsigned char *src, int len, enum
 int get_str_basic(unsigned char *out_buffer, unsigned char *in_buffer, int trim_subs,
 		  enum ccx_encoding_type in_enc, enum ccx_encoding_type out_enc, int max_len)
 {
+#ifndef DISABLE_RUST
+	return ccxr_get_str_basic(out_buffer, in_buffer, trim_subs, in_enc, out_enc, max_len);
+#else
 	int last_non_blank = -1;
 	int first_non_blank = -1;
 	int len = 0;
@@ -305,7 +312,6 @@ int get_str_basic(unsigned char *out_buffer, unsigned char *in_buffer, int trim_
 		*out_buffer = 0;
 		return 0;
 	}
-
 	// change encoding only when required
 	switch (in_enc)
 	{
@@ -331,6 +337,7 @@ int get_str_basic(unsigned char *out_buffer, unsigned char *in_buffer, int trim_
 		return (unsigned)len; // Return length
 
 	return 0; // Return length
+#endif
 }
 
 int write_subtitle_file_footer(struct encoder_ctx *ctx, struct ccx_s_write *out)
@@ -631,8 +638,8 @@ int write_cc_buffer_as_simplexml(struct eia608_screen *data, struct encoder_ctx
 		if (data->row_used[i])
 		{
 			write_cc_line_as_simplexml(data, context, i);
+			wrote_something = 1;
 		}
-		wrote_something = 1;
 	}
 	return wrote_something;
 }

src/lib_ccx/ccx_encoders_spupng.c

@@ -29,18 +29,6 @@ FT_Face face_regular = NULL;
 FT_Face face_italics = NULL;
 FT_Face face = NULL;
 
-struct spupng_t
-{
-	FILE *fpxml;
-	FILE *fppng;
-	char *dirname;
-	char *pngfile;
-	char *relative_path_png;
-	int fileIndex;
-	int xOffset;
-	int yOffset;
-};
-
 #define CCPL (ccfont2_width / CCW * ccfont2_height / CCH)
 
 static int initialized = 0;

src/lib_ccx/ccx_encoders_structs.h

@@ -29,4 +29,16 @@ struct ccx_s_write
 
 };
 
+struct spupng_t
+{
+	FILE *fpxml;
+	FILE *fppng;
+	char *dirname;
+	char *pngfile;
+	char *relative_path_png;
+	int fileIndex;
+	int xOffset;
+	int yOffset;
+};
+
 #endif

src/rust/build.rs

@@ -12,6 +12,9 @@ fn main() {
         "writercwtdata",
         "version",
         "set_binary_mode",
+        "net_send_header", // shall be removed after NET
+        "write_spumux_footer",
+        "write_spumux_header",
     ]);
 
     #[cfg(feature = "hardsubx_ocr")]
@@ -39,6 +42,7 @@ fn main() {
         "ccx_encoding_type",
         "ccx_decoder_608_settings",
         "ccx_decoder_608_report",
+        "eia608_screen",
         "uint8_t",
         "word_list",
     ]);

src/rust/lib_ccxr/src/encoder/mod.rs

@@ -0,0 +1,4 @@
+pub mod txt_helpers;
+/* Note
+This is a part of the encoder library, which is made in pure rust; hence it's kept in `lib_ccxr` instead of `src`.
+ */