Running consumption tracker charged by a decoder against its policy. More...

Collaboration diagram for ra8_decomp_budget_t:

Data Fields
ra8_decomp_limits_t	limits
	Policy in force for this budget.
uint64_t	out_bytes
	Decompressed bytes produced so far.
uint64_t	in_bytes
	Compressed bytes consumed so far.
uint32_t	entries
	Archive entries enumerated so far.
uint32_t	iters
	Decode-loop turns charged so far.
uint8_t	depth
	Current stacked decode-layer depth.

Detailed Description

Running consumption tracker charged by a decoder against its policy.

One budget tracks one decode unit (streaming decoders) or one archive enumeration (walkers). Decoders charge it as they go: ra8_decomp_budget_charge_output after emitting bytes, ra8_decomp_budget_charge_entry per enumerated member, ra8_decomp_budget_charge_iter per decode-loop turn, and ra8_decomp_budget_enter / ra8_decomp_budget_leave around a stacked layer. Each charge fails closed with the axis-specific error the moment its bound is crossed.

Invariant: depth <= limits.max_depth between charges.; Counters only grow (except depth, which is balanced by enter/leave).

Example:: ra8_decomp_budget_t b = {};

(void)ra8_decomp_budget_init(&b, nullptr); // default policy

while (more_input) {

RA8_RETURN_ON_ERROR(ra8_decomp_budget_charge_iter(&b), tag, "loop cap");

// ... decode one chunk producing n bytes from in_total consumed ...

RA8_RETURN_ON_ERROR(ra8_decomp_budget_charge_output(&b, in_total, n), tag, "bomb");

}

RA8_RETURN_ON_ERROR
#define RA8_RETURN_ON_ERROR(err, tag, message)
Early return on error, propagating the code upward.
Definition ra8_check.h:184

ra8_decomp_budget_charge_output
ra8_err_t ra8_decomp_budget_charge_output(ra8_decomp_budget_t *b, uint64_t in_total, uint64_t out_delta)
Charge decompressed output against the cap and ratio bounds.
Definition ra8_decomp_limits.c:158

ra8_decomp_budget_charge_iter
ra8_err_t ra8_decomp_budget_charge_iter(ra8_decomp_budget_t *b)
Charge one decode-loop turn against the iteration budget.
Definition ra8_decomp_limits.c:186

ra8_decomp_budget_init
ra8_err_t ra8_decomp_budget_init(ra8_decomp_budget_t *b, const ra8_decomp_limits_t *limits)
Bind a budget to a policy (or the default policy) and zero it.
Definition ra8_decomp_limits.c:142

ra8_decomp_budget_t
Running consumption tracker charged by a decoder against its policy.
Definition ra8_decomp_limits.h:169

Definition at line 169 of file ra8_decomp_limits.h.

Field Documentation

uint8_t ra8_decomp_budget_t::depth

Current stacked decode-layer depth.

Definition at line 175 of file ra8_decomp_limits.h.

uint32_t ra8_decomp_budget_t::entries

Archive entries enumerated so far.

Definition at line 173 of file ra8_decomp_limits.h.

uint64_t ra8_decomp_budget_t::in_bytes

Compressed bytes consumed so far.

Definition at line 172 of file ra8_decomp_limits.h.

uint32_t ra8_decomp_budget_t::iters

Decode-loop turns charged so far.

Definition at line 174 of file ra8_decomp_limits.h.

ra8_decomp_limits_t ra8_decomp_budget_t::limits

Policy in force for this budget.

Definition at line 170 of file ra8_decomp_limits.h.

uint64_t ra8_decomp_budget_t::out_bytes

Decompressed bytes produced so far.

Definition at line 171 of file ra8_decomp_limits.h.

The documentation for this struct was generated from the following file: