Design

What obSCEne announces before it acts, how it checks from the failure side, how the sections are ordered, and what it refuses to invent.

OUTPUT.md is the report format; WORKFLOW.md is the loop this feeds.

Announce before attempting

Every check prints its identity before making the call:

OBS|try|020-memory/map|libkernel|sceKernelMapDirectMemory
OBS|res|020-memory/map|pass|0x8804000000|

Under an emulator, an unimplemented function usually crashes the process. The stream then stops, and the last line names the exact call that did it. A report that ends on a try is a stack trace with one frame. Everything else in the program is arranged to keep this property.

Checks from the failure side

Much of the suite passes deliberately invalid arguments and expects an error:

int rc = sceKernelClose(-1);   /* must fail */

This needs no struct layouts, and a guessed layout corrupts the stack far from the mistake. It still shows the function exists, is reachable, validates its arguments and returns something plausible - the things an implementation returning a constant gets wrong.

An implementation that fails everything passes every negative check. Negative checks prove argument validation; positive checks prove the function does its job.

035-libc and 037-math are positive checks over an interface ISO C defines completely, so every signature is certain and every check asks whether the function works: calloc returns zeroed memory, realloc preserves contents, qsort sorts, snprintf reports the length it would have written. The maths section uses no tolerances: every expected value is exactly representable, so floor(-1.5) must be -2.0.

018-relational compares results to each other rather than to an expected value: two live event flags do not share a handle, a counting semaphore refuses a third claim against two signals, released memory is allocatable again. These hold whatever the platform's actual numbers are, so they need no authority, which makes them usable on the vendor surface.

Reading a report

The binary emits one machine-readable format. Colour and grouping are presentation and live in the tool, so the guest stays small:

make pretty                          # colour, grouped by section
./build/obscene-host | obscene-tool pretty

OUTPUT.md is the format contract, and parsers depend on it.

Comparing runs

make host && ./build/obscene-host > baseline.txt
# ...change the emulator...
make diff BASELINE=baseline.txt

  improved   037-math/sqrt: skip -> pass
  value      900-surface/libc: 0x39 -> 0x4d
7 improved, 0 regressed, 70 unchanged
tally: pass +7, skip -7

Exit 0 means no regressions; 1 means something got worse. A regression is a check that got worse, not a check that is failing. skip ranks below fail, because a check that stopped running says less than one that ran and failed. A check that vanishes from the report counts the same way.

Section order

Sections run from the base of the platform to high level, so a failure at the top is read before the failures below that depend on it. src/probe/registry.c is the authoritative, ordered list. The landmarks:

A check whose prerequisites were not met is skipped, not failed, so one broken allocator does not turn everything below it red. A check whose symbol the loader could not resolve is also skipped: every platform declaration is weak, so an absent function is skipped rather than jumped to.

Display and user

obSCEne opens its display against a user obtained from the user service. When no initial user can be determined it does not open a display and does not guess a user id; the text report is still complete.

Presence and behaviour

The behavioural sections ask whether a function works, and each costs a confident signature. The census asks only whether it exists, which costs a name, so it scales to the whole platform.

The census never calls anything. Every censused name is declared as data rather than as a function, so the type system forbids the call. 910-bulk is the one exception: it casts an address rather than redeclaring the name, so the exception stays inside one expression and no other translation unit can call these names. It is compiled in only under OBS_BULK and is the one part of the program expected to end the process.

Presence measures the loader as much as the platform. A loader that resolves every import through a generic stub reports the whole census present, including libraries it does not implement; one that resolves only what it implements reports the rest absent. Read the census beside 007-responsive, never alone. 910-bulk exists because a resolved address and an implementation are different claims.

A wrong name in the census is a visible, harmless false negative. A wrong arity in a behavioural check corrupts the stack and crashes somewhere unrelated. That asymmetry is why the census casts a wider net.

900-surface/control runs first and validates the census, probing one symbol that must resolve and one that must not. On a platform implementing none of the surface, "everything absent" and "the presence test is broken" look identical without it.

Nothing is invented

Every declaration in include/obscene/platform.h is a signature this project is confident about. Where an arity or a struct layout is uncertain, the function is left out.

The symbol and library strings are ABI identifiers. The import hash is computed from the symbol name, so they stay exactly as the platform spells them. Prose elsewhere avoids vendor branding.