// SPDX-License-Identifier: GPL-3.0-or-later
//
// This file is part of CProof.
// See LICENSE for the full GPLv3 text and the special OpenSSL linking exception.

#ifndef BENCH_COMMON_H
#define BENCH_COMMON_H

#include <stdint.h>
#include <stddef.h>
#include <sys/resource.h>

#include <glib.h>

// Wall-clock monotonic milliseconds since some epoch. Use for elapsed-time
// arithmetic only (subtract two values).
double bench_now_ms(void);

// Format a byte count as "1.23 GB" / "500 MB" / "42 KB" / "9 B".
// Returns a freshly allocated string; caller must g_free.
char* bench_fmt_bytes(uint64_t bytes);

// Format a duration in milliseconds as a human-friendly string.
char* bench_fmt_ms(double ms);

// Resolve BENCH_VOLUME env: "small" / "medium" / "max" / unset.
typedef enum {
    BENCH_VOLUME_SMALL,  // 10k lines / 1 contact / 1 year
    BENCH_VOLUME_MEDIUM, // 500k lines / 1 contact / 5 years
    BENCH_VOLUME_MAX,    // 5M lines  / 1 contact / 10 years
} bench_volume_t;

bench_volume_t bench_volume_from_env(void);
const char* bench_volume_name(bench_volume_t v);

// Drop OS page cache for a path (so a subsequent read measures cold I/O).
// On Linux this is best-effort: we open the file, posix_fadvise(DONTNEED).
// Returns TRUE on success.
gboolean bench_drop_page_cache(const char* path);

// Available bytes in the filesystem hosting `path`. Returns -1 on failure.
int64_t bench_fs_free_bytes(const char* path);

// Best-of-N timing: run `fn(arg)` `runs` times, return the minimum elapsed-ms.
// Optionally records peak RSS over runs into *peak_rss_kb.
typedef void (*bench_fn_t)(void* arg);
double bench_run_best_of(int runs, bench_fn_t fn, void* arg, long* peak_rss_kb);

// Get current peak RSS in KB via getrusage().
long bench_peak_rss_kb(void);

#endif