sh_classify.h File Reference

Book-format classification by file extension (long-name aware, #633). More...

#include <stddef.h>
#include <stdint.h>
#include <string.h>

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Enumerations
enum	sh_book_fmt_t : uint8_t {   k_sh_fmt_rabook = 0U ,   k_sh_fmt_epub = 1U ,   k_sh_fmt_cbz = 2U ,   k_sh_fmt_cbr = 3U ,   k_sh_fmt_cbt = 4U }
	Book container format behind a shelf entry / the open book. More...

Functions
static bool	sh_fmt_is_comic (sh_book_fmt_t fmt)
	True if fmt is a comic-archive container (CBZ, CBR, or CBT).
static char	sh_ascii_lower (char c)
	Fold one ASCII letter to lower case (non-letters returned unchanged).
static bool	sh_ext_match (const char *name, const char *ext)
	Case-insensitive test that name ends in the extension ext.
static bool	sh_book_classify (const char *name, sh_book_fmt_t *out_fmt)
	Classify a root file name into a book format; true if it is a book.

Detailed Description

Book-format classification by file extension (long-name aware, #633).

The shelf scans the FAT root and decides which files are books and in what container format. Since #600 gave ra8_fs VFAT long-name write, the card carries real extensions (.rabook, .epub) rather than the 8.3 truncations (.RBK, .EPB) the tools used to emit, so the classifier matches BOTH: the long forms and, so existing 8.3-named cards still resolve, the legacy short forms. Matching is case-insensitive because FAT hands back 8.3 names upper-cased while long names keep their authored case.

This header is board-free (string logic only), so sh_sd.c and the host classification test share one implementation instead of a copy.

Copyright

Copyright (c) 2026 Brighton Sikarskie SPDX-License-Identifier: MIT

Since

0.1.0

Definition in file sh_classify.h.

Enumeration Type Documentation

sh_book_fmt_t

enum sh_book_fmt_t : uint8_t

Book container format behind a shelf entry / the open book.

Both text formats render through the same screens via the sh_book.c backend: .rabook is the pre-parsed book blob, demand-paged through the chunked reader (baked or on SD); .epub is parsed on-device by epub (SD only). The three comic containers route through sh_comic.c as image-page readers.

Since

0.1.0

Enumerator
k_sh_fmt_rabook	book RBKC container (demand-paged chunks).
k_sh_fmt_epub	EPUB parsed on-device by epub.
k_sh_fmt_cbz	Comic archive: ZIP of page images (.cbz).
k_sh_fmt_cbr	Comic archive: RAR of page images (.cbr).
k_sh_fmt_cbt	Comic archive: tar of page images (.cbt).

Definition at line 37 of file sh_classify.h.

Function Documentation

sh_ascii_lower()

char sh_ascii_lower ( char c )

inlinestatic

Fold one ASCII letter to lower case (non-letters returned unchanged).

Parameters

[in]

c

Byte to fold.

Returns

The lower-case letter, or c unchanged when it is not A..Z.

Return values

char	Case-folded byte.

Precondition

c is a single byte.

Postcondition

No state is modified (pure function).

Note

Thread-safe: pure function of its argument.

Since

0.1.0

Definition at line 74 of file sh_classify.h.

Referenced by sh_ext_match().

sh_book_classify()

bool sh_book_classify ( const char * name, sh_book_fmt_t * out_fmt )

inlinestatic

Classify a root file name into a book format; true if it is a book.

Recognises the long extensions the tools now write (.rabook, .epub) and, so existing 8.3-named cards keep resolving, their legacy 8.3 truncations (.rbk, .epb). Comics already had 3-char extensions, so .cbz / .cbr / .cbt never truncated. Matching is case-insensitive (sh_ext_match).

Parameters

[in]	name	NUL-terminated root file name (non-NULL).
[out]	out_fmt	Receives the container format when name is a book.

Returns

Whether name names a book this shelf can open.

Return values

true	name matched a known book extension; *out_fmt is set.
false	name is not a book; *out_fmt is untouched.

Precondition

name and out_fmt are non-NULL.

name is a single root directory entry name.

Postcondition

On true *out_fmt holds the classified sh_book_fmt_t.

On false no output is written.

Note

Thread-safe: writes only out_fmt.

Since

0.1.0

Definition at line 129 of file sh_classify.h.

References k_sh_fmt_cbr, k_sh_fmt_cbt, k_sh_fmt_cbz, k_sh_fmt_epub, k_sh_fmt_rabook, and sh_ext_match().

Referenced by sh_sd_listdir_cb().

sh_ext_match()

bool sh_ext_match ( const char * name, const char * ext )

inlinestatic

Case-insensitive test that name ends in the extension ext.

Requires at least one character before ext, so a name that is only the extension (e.g. .epub) is not a book. Folds both sides to lower case, so .EPB matches .epb and Book.EPUB matches .epub.

Parameters

[in]	name	NUL-terminated file name (non-NULL).
[in]	ext	NUL-terminated extension including its dot, e.g. .rabook.

Returns

Whether name ends in ext with a non-empty stem.

Return values

true	name is longer than ext and its tail case-matches ext.
false	name is not longer than ext or the tail differs.

Precondition

name and ext are non-NULL and NUL-terminated.

ext is a file extension leading with ..

Postcondition

No state is modified (pure function).

Note

Thread-safe: pure function over its arguments.

Since

0.1.0

Definition at line 95 of file sh_classify.h.

References sh_ascii_lower(), and strlen().

Referenced by sh_book_classify().

sh_fmt_is_comic()

bool sh_fmt_is_comic ( sh_book_fmt_t fmt )

inlinestatic

True if fmt is a comic-archive container (CBZ, CBR, or CBT).

Both route through sh_comic.c (::comic) rather than the text-book screens, so this predicate is the single dispatch test the shelf/open path branches on.

Parameters

[in]

fmt

Container format from a shelf entry / the open book.

Returns

true for k_sh_fmt_cbz, k_sh_fmt_cbr, or k_sh_fmt_cbt.

Return values

true	fmt is a comic archive (image-page reader).
false	fmt is a text book (rabook / epub).

Precondition

fmt is a valid sh_book_fmt_t.

Postcondition

No state is modified (pure predicate).

Note

Thread-safe: pure function of its argument.

Since

0.1.0

Definition at line 59 of file sh_classify.h.

References k_sh_fmt_cbr, k_sh_fmt_cbt, and k_sh_fmt_cbz.

Referenced by sh_book_open(), sh_comic_open(), and sh_select_book().