test.c

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <stdbool.h>

// 直接包含 bbr.c 实现文件，省略头文件
#include "bbrlite/bbrlite.c"

#define HISTORY_SIZE 100
#define NUM_BBRS 10
#define MSS 1500

/**
 * The following are simulated attribute values
 */

// 产生约10%概率的bool
static bool rand_bool_10pct() {
    return (rand() % 10) == 0;
}
// 产生约20%概率的bool
static bool rand_bool_20pct() {
    return (rand() % 5) == 0;
}
// 模拟带宽（单位：scaled 带宽，1<<24是单位），范围 1~10Mbps
static uint32_t rand_bw() {
    return ((uint32_t)(1000 + rand() % 9000)) << BW_SCALE;
}
// 模拟RTT，单位微秒，10~100ms
static uint32_t rand_rtt() {
    return 10000 + rand() % 90000;
}
// 模拟acked样本，单位任意，1~20000
static uint32_t rand_acked() {
    return 1 + rand() % 20000;
}

int main(void) {
    srand((unsigned int)time(NULL));

    // 预分配每个BBR实例的缓冲区
	// Pre allocate buffer for each BBR instance
    uint32_t bw_bufs[NUM_BBRS][HISTORY_SIZE];
    uint32_t rtt_bufs[NUM_BBRS][HISTORY_SIZE];
    uint32_t acked_bufs[NUM_BBRS][HISTORY_SIZE];
    bool loss_bufs[NUM_BBRS][HISTORY_SIZE];
    bool app_limited_bufs[NUM_BBRS][HISTORY_SIZE];

    bbr_t bbrs[NUM_BBRS];

    // 初始化每个BBR实例
	// Init
    for (int i = 0; i < NUM_BBRS; i++) {
        bbr_init(&bbrs[i], bw_bufs[i], rtt_bufs[i], acked_bufs[i], loss_bufs[i], app_limited_bufs[i], HISTORY_SIZE);
    }

    // 模拟10秒，每秒生成随机样本，调用bbr_update并打印状态
	// Simulate for 10 seconds, generate random samples per second, call `bbr_update` and print status
    for (int sec = 0; sec < 10; sec++) {
        printf("== Time %d s ==\n", sec);

        for (int i = 0; i < NUM_BBRS; i++) {
            // 追加随机样本
			// Add random samples
            bbr_append_bw(&bbrs[i], rand_bw());
            bbr_append_rtt(&bbrs[i], rand_rtt());
            bbr_append_acked(&bbrs[i], rand_acked());
            bbr_append_loss(&bbrs[i], rand_bool_10pct());
            bbr_append_app_limited(&bbrs[i], rand_bool_20pct());

            // 更新内部状态
			// Update internal status
            bbr_update(&bbrs[i]);

            // 获取建议速率和窗口
			// Get suggested speed and window
            uint64_t pacing_rate = bbr_pacing_rate(&bbrs[i], MSS);
            uint32_t cwnd = bbr_cwnd(&bbrs[i]);

            // 输出
			// Output
            printf("BBR %d: mode=%d, bw_hi=%u, min_rtt=%u, pacing_rate=%llu, cwnd=%u\n",
                i,
                (int)bbrs[i].mode,
                bbrs[i].bw_hi >> BW_SCALE,     // 以Mbps简单表示
                bbrs[i].min_rtt_us,
                pacing_rate,
                cwnd);
        }
        printf("\n");

        sleep(1);
    }

    return 0;
}