code wiki / _hdl_build / nx_mobi_cover.nx
nx_mobi_cover.nx
buildroot/runtime/_hdl_build/nx_mobi_cover.nx
about
nx_mobi_cover.nx -- SHARED embedded-cover extraction for the Kindle decoders (DRY: nx_mobi_book + nx_kf8_book both
call it). The cover is read out of the file ITSELF, offline -- never generated, never downloaded (how Calibre does
it). Grounded on the registered MOBI spec (mobileread-mobi-spec.ref): the MOBI header's "First Image index" lives
at rec0off+108 (record-0-relative); EXTH 201 coveroffset / 202 thumboffset are ADDED to it to find the cover PDB
record. Image records are absolute in the PDB, so the SAME record-0 First Image index serves MOBI6 and KF8 (a dual
file shares its image records). Detects JPEG/PNG/GIF magic and writes <dir>/cover.<ext>; sets covername (or "").
Returns 1 if a cover was written, else 0. license_tier: ORIGINAL
dependencies 2 imports · 2 importers
imports: nx_syscalls.nxnx_itoa_lib.nx
imported by: nx_kf8_book.nxnx_mobi_book.nx
structs
| none |
consts
| 10 | const K_MAGIC_1024: i64 = 1024 |
functions
| 12 | func mc_slen(s: *u8) -> i64 { var n: i64=0; while s[n]!=(0 as u8){n=n+1} return n } called by 1: mc_p |
| 13 | func mc_cat(dst: *u8, off: i64, s: *u8) -> i64 { var i: i64=0; while s[i]!=(0 as u8){dst[off+i]=s[i];i=i+1} return off+i } called by 1: mobi_extract_cover |
| 14 | func mc_be32(b: *u8, o: i64) -> i64 { return ((b[o] as i64)<<24)|((b[o+1] as i64)<<16)|((b[o+2] as i64)<<8)|(b[o+3] as i64) } called by 1: mobi_extract_cover |
| 15 | func mc_p(s: *u8) -> i64 { sys_write(1, s, mc_slen(s)); return 0 } |
| 20 | func mc_pn(v: i64) -> i64 { nxi_out(v); return 0 } |
| 22 | func mobi_extract_cover(z: *u8, zl: i64, numRec: i64, rec0off: i64, coveroff: i64, coverfound: i64, thumboff: i64, thumbfound: i64, dir: *u8, covername: *u8) -> i64 |