AU_BSM_TO_ERRNO(3)

💅 AU_BSM_TO_ERRNO(3) — bestie edition 🎀

okay so this one lives in the Library Functions Manual, specifically the Basic Security Module Library aka libbsm, and you link it with -lbsm. that's the vibe check for today ✨

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🌸 NAME 🌸

au_bsm_to_errno, au_errno_to_bsm, au_strerror — the three little besties that convert between BSM and local error numbers 🦋

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🎀 LIBRARY 🎀

Basic Security Module Library (libbsm, -lbsm) 💖

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✨ SYNOPSIS ✨

#include <bsm/libbsm.h>

int
au_bsm_to_errno(u_char bsm_error, int *errorp);

u_char
au_errno_to_bsm(int error);

const char *
au_strerror(int bsm_error);

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💅 DESCRIPTION 💅

so these interfaces exist to convert between two whole error-number spaces: the local one (errno(2)) and the BSM one you'll find chillin' in BSM return tokens. two worlds, one bridge, iconic 🌈

• au_bsm_to_errno() — takes a BSM error value, bsm_error, and converts it into an errno(2) that gets stored in the integer pointed to by errorp if it works out. 🫶

heads up bestie: this call fails if the BSM error can't be mapped into a local error number, which can totes happen if the return token was generated on a different operating system. literally not our fault 😭

• au_errno_to_bsm() — takes a local errno(2) value and hands back the BSM error number for it. this call cannot fail 💀 instead it returns a BSM error number that tells a later decoder "yeah, this error could not be encoded." graceful, honestly 👑
• au_strerror() — converts a BSM error value into a string. usually it converts to a local error number first and then uses the local strerror(3), but it will also work for errors that aren't locally defined. flexible queen 🌟

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🔥 RETURN VALUES 🔥

• on success, au_bsm_to_errno() returns 0 plus a converted error value ✨
• on failure, it returns -1 but does not set errno(2). not me dropping the ball on the errno, i know 🙈
• on success, au_strerror() returns a pointer to an error string 🎀
• on failure, it returns NULL. that's it. that's the whole mood 💀

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👑 SEE ALSO 👑

au_to_return(3), au_to_return32(3), au_to_return64(3), libbsm(3) — go read those too, iykyk 📚

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🦋 HISTORY 🦋

au_bsm_to_errno() and au_errno_to_bsm() were introduced in OpenBSM 1.1. throwback era ngl ⭐

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💜 AUTHORS 💜

these functions were implemented by Robert Watson under contract to Apple Inc. 🍓

also: the Basic Security Module (BSM) interface to audit records and the audit event stream format were defined by Sun Microsystems. legends, fr fr ☀️

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💀 BUGS 💀

au_strerror cannot provide localized strings for errors that aren't available in the local operating system. soz 😭 that's just how it is.

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🧚 sign-off 🧚

this cutie came from Debian and the page is dated December 8, 2008 — vintage, honestly 💅 bye bestie, go audit something 🎀✨