libcreg(3)

👑 libcreg — the library that reads the Windows 9x/Me Registry File (CREG) format 👑

okay bestie, gather round, because this one is a whole vibe: libcreg is the library that opens up .creg files — the registry format from Windows 9x/Me era. vintage, iconic, a little chaotic. let's go. 💅

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🌸 NAME 🌸

libcreg.h — Library to access the Windows 9x/Me Registry File (CREG) format

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✨ SYNOPSIS ✨

first things first, you gotta include the header, obviously:

#include <libcreg.h>

💫 Support functions 💫

these are the lil helpers that tell you stuff about the library itself, no file needed:

const char *
libcreg_get_version(void);

int
libcreg_get_access_flags_read(void);

int
libcreg_get_codepage(int *codepage, libcreg_error_t **error);

int
libcreg_set_codepage(int codepage, libcreg_error_t **error);

int
libcreg_check_file_signature(const char *filename,
    libcreg_error_t **error);

Available when compiled with wide character string support:

int
libcreg_check_file_signature_wide(const wchar_t *filename,
    libcreg_error_t **error);

Available when compiled with libbfio support:

int
libcreg_check_file_signature_file_io_handle(libbfio_handle_t *bfio_handle,
    libcreg_error_t **error);

🫶 Notify functions 🫶

so when you want libcreg to actually talk to you (or to a stream):

void
libcreg_notify_set_verbose(int verbose);

int
libcreg_notify_set_stream(FILE *stream, libcreg_error_t **error);

int
libcreg_notify_stream_open(const char *filename,
    libcreg_error_t **error);

int
libcreg_notify_stream_close(libcreg_error_t **error);

😭 Error functions 😭

for when things go sideways (and they will, it's fine):

void
libcreg_error_free(libcreg_error_t **error);

int
libcreg_error_fprint(libcreg_error_t *error, FILE *stream);

int
libcreg_error_sprint(libcreg_error_t *error, char *string, size_t size);

int
libcreg_error_backtrace_fprint(libcreg_error_t *error, FILE *stream);

int
libcreg_error_backtrace_sprint(libcreg_error_t *error, char *string,
    size_t size);

🎀 File functions 🎀

this is where the actual .creg file gets opened and poked at:

int
libcreg_file_initialize(libcreg_file_t **file, libcreg_error_t **error);

int
libcreg_file_free(libcreg_file_t **file, libcreg_error_t **error);

int
libcreg_file_signal_abort(libcreg_file_t *file,
    libcreg_error_t **error);

int
libcreg_file_open(libcreg_file_t *file, const char *filename,
    int access_flags, libcreg_error_t **error);

int
libcreg_file_close(libcreg_file_t *file, libcreg_error_t **error);

int
libcreg_file_is_corrupted(libcreg_file_t *file,
    libcreg_error_t **error);

int
libcreg_file_get_ascii_codepage(libcreg_file_t *file,
    int *ascii_codepage, libcreg_error_t **error);

int
libcreg_file_set_ascii_codepage(libcreg_file_t *file,
    int ascii_codepage, libcreg_error_t **error);

int
libcreg_file_get_format_version(libcreg_file_t *file,
    uint16_t *major_version, uint16_t *minor_version,
    libcreg_error_t **error);

int
libcreg_file_get_type(libcreg_file_t *file, uint32_t *file_type,
    libcreg_error_t **error);

int
libcreg_file_get_root_key(libcreg_file_t *file,
    libcreg_key_t **root_key, libcreg_error_t **error);

int
libcreg_file_get_key_by_utf8_path(libcreg_file_t *file,
    const uint8_t *utf8_string, size_t utf8_string_length,
    libcreg_key_t **key, libcreg_error_t **error);

int
libcreg_file_get_key_by_utf16_path(libcreg_file_t *file,
    const uint16_t *utf16_string, size_t utf16_string_length,
    libcreg_key_t **key, libcreg_error_t **error);

Available when compiled with wide character string support:

int
libcreg_file_open_wide(libcreg_file_t *file, const wchar_t *filename,
    int access_flags, libcreg_error_t **error);

Available when compiled with libbfio support:

int
libcreg_file_open_file_io_handle(libcreg_file_t *file,
    libbfio_handle_t *file_io_handle, int access_flags,
    libcreg_error_t **error);

🦋 Key functions 🦋

registry keys are the moment, honestly — getting their names, their values, their sub-keys:

int
libcreg_key_free(libcreg_key_t **key, libcreg_error_t **error);

int
libcreg_key_is_corrupted(libcreg_key_t *key, libcreg_error_t **error);

int
libcreg_key_get_offset(libcreg_key_t *key, off64_t *offset,
    libcreg_error_t **error);

int
libcreg_key_get_name_size(libcreg_key_t *key, size_t *string_size,
    libcreg_error_t **error);

int
libcreg_key_get_name(libcreg_key_t *key, uint8_t *string,
    size_t string_size, libcreg_error_t **error);

int
libcreg_key_get_utf8_name_size(libcreg_key_t *key,
    size_t *utf8_string_size, libcreg_error_t **error);

int
libcreg_key_get_utf8_name(libcreg_key_t *key, uint8_t *utf8_string,
    size_t utf8_string_size, libcreg_error_t **error);

int
libcreg_key_get_utf16_name_size(libcreg_key_t *key,
    size_t *utf16_string_size, libcreg_error_t **error);

int
libcreg_key_get_utf16_name(libcreg_key_t *key, uint16_t *utf16_string,
    size_t utf16_string_size, libcreg_error_t **error);

int
libcreg_key_get_number_of_values(libcreg_key_t *key,
    int *number_of_values, libcreg_error_t **error);

int
libcreg_key_get_value_by_index(libcreg_key_t *key, int value_index,
    libcreg_value_t **value, libcreg_error_t **error);

int
libcreg_key_get_value_by_utf8_name(libcreg_key_t *key,
    const uint8_t *utf8_string, size_t utf8_string_length,
    libcreg_value_t **value, libcreg_error_t **error);

int
libcreg_key_get_value_by_utf16_name(libcreg_key_t *key,
    const uint16_t *utf16_string, size_t utf16_string_length,
    libcreg_value_t **value, libcreg_error_t **error);

int
libcreg_key_get_number_of_sub_keys(libcreg_key_t *key,
    int *number_of_sub_keys, libcreg_error_t **error);

int
libcreg_key_get_sub_key_by_index(libcreg_key_t *key, int sub_key_index,
    libcreg_key_t **sub_key, libcreg_error_t **error);

int
libcreg_key_get_sub_key_by_utf8_name(libcreg_key_t *key,
    const uint8_t *utf8_string, size_t utf8_string_length,
    libcreg_key_t **sub_key, libcreg_error_t **error);

int
libcreg_key_get_sub_key_by_utf8_path(libcreg_key_t *key,
    const uint8_t *utf8_string, size_t utf8_string_length,
    libcreg_key_t **sub_key, libcreg_error_t **error);

int
libcreg_key_get_sub_key_by_utf16_name(libcreg_key_t *key,
    const uint16_t *utf16_string, size_t utf16_string_length,
    libcreg_key_t **sub_key, libcreg_error_t **error);

int
libcreg_key_get_sub_key_by_utf16_path(libcreg_key_t *key,
    const uint16_t *utf16_string, size_t utf16_string_length,
    libcreg_key_t **sub_key, libcreg_error_t **error);

🍓 Value functions 🍓

and here's where you grab the actual data out of a value — 32-bit, 64-bit, strings, binary, whatever she's carrying:

int
libcreg_value_free(libcreg_value_t **value, libcreg_error_t **error);

int
libcreg_value_is_corrupted(libcreg_value_t *value,
    libcreg_error_t **error);

int
libcreg_value_get_offset(libcreg_value_t *value, off64_t *offset,
    libcreg_error_t **error);

int
libcreg_value_get_name_size(libcreg_value_t *value, size_t *string_size,
    libcreg_error_t **error);

int
libcreg_value_get_name(libcreg_value_t *value, uint8_t *string,
    size_t string_size, libcreg_error_t **error);

int
libcreg_value_get_utf8_name_size(libcreg_value_t *value,
    size_t *utf8_string_size, libcreg_error_t **error);

int
libcreg_value_get_utf8_name(libcreg_value_t *value,
    uint8_t *utf8_string, size_t utf8_string_size,
    libcreg_error_t **error);

int
libcreg_value_get_utf16_name_size(libcreg_value_t *value,
    size_t *utf16_string_size, libcreg_error_t **error);

int
libcreg_value_get_utf16_name(libcreg_value_t *value,
    uint16_t *utf16_string, size_t utf16_string_size,
    libcreg_error_t **error);

int
libcreg_value_get_value_type(libcreg_value_t *value,
    uint32_t *value_type, libcreg_error_t **error);

int
libcreg_value_get_value_data_size(libcreg_value_t *value,
    size_t *value_data_size, libcreg_error_t **error);

int
libcreg_value_get_value_data(libcreg_value_t *value,
    uint8_t *value_data, size_t value_data_size,
    libcreg_error_t **error);

int
libcreg_value_get_value_32bit(libcreg_value_t *value,
    uint32_t *value_32bit, libcreg_error_t **error);

int
libcreg_value_get_value_64bit(libcreg_value_t *value,
    uint64_t *value_64bit, libcreg_error_t **error);

int
libcreg_value_get_value_utf8_string_size(libcreg_value_t *value,
    size_t *utf8_string_size, libcreg_error_t **error);

int
libcreg_value_get_value_utf8_string(libcreg_value_t *value,
    uint8_t *utf8_string, size_t utf8_string_size,
    libcreg_error_t **error);

int
libcreg_value_get_value_utf16_string_size(libcreg_value_t *value,
    size_t *utf16_string_size, libcreg_error_t **error);

int
libcreg_value_get_value_utf16_string(libcreg_value_t *value,
    uint16_t *utf16_string, size_t utf16_string_size,
    libcreg_error_t **error);

int
libcreg_value_get_value_binary_data_size(libcreg_value_t *value,
    size_t *size, libcreg_error_t **error);

int
libcreg_value_get_value_binary_data(libcreg_value_t *value,
    uint8_t *binary_data, size_t size, libcreg_error_t **error);

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💜 DESCRIPTION 💜

okay so, the one that's documented here: the libcreg_get_version() function is used to retrieve the library version. that's the whole tea. 🫖

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🌈 RETURN VALUES 🌈

most of the functions return NULL or -1 on error — it depends on the return type, so like, don't @ her. for the actual return values, go look at libcreg.h, that's where the receipts live.

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🧚 ENVIRONMENT 🧚

None. literally nothing. no environment variables, no vibes to set, nada. 🕳️

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💀 FILES 💀

None. also nothing. she's self-contained, main character energy. 👑

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⭐ NOTES ⭐

libcreg can be compiled with wide character support (wchar_t). yes bestie, the fancy wide chars.

to compile libcreg with wide character support, use:

./configure --enable-wide-character-type=yes

or define:

_UNICODE

or:

UNICODE

during compilation.

and heads up: LIBCREG_WIDE_CHARACTER_TYPE in libcreg/features.h can be used to determine if libcreg was compiled with wide character support. so you can vibe-check your build. 🔍

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🙈 BUGS 🙈

please report bugs of any kind on the project issue tracker: https://github.com/libyal/libcreg/issues

(any kind. even the silly ones. they want to know. 🫶)

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🎀 AUTHOR 🎀

These man pages are generated from "libcreg.h".

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💖 COPYRIGHT 💖

Copyright (C) 2013-2024, Joachim Metz <joachim.metz@gmail.com>.

This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. (read it again. NO warranty. dramatic but important, periodt. 💅)

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🌟 SEE ALSO 🌟

• the libcreg.h include file

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and that's the whole page, bestie — libcreg, from the libcreg manual, dated April 10, 2019. go forth and parse those 9x/Me registries. slay. 🦋✨