160 lines
3.6 KiB
C
Executable File
160 lines
3.6 KiB
C
Executable File
/*
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* Copyright (c) 2011-2023, Shanghai Real-Thread Electronic Technology Co.,Ltd
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*
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* Change Logs:
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* Date Author Notes
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* 2020-12-18 quanzhao the first version
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*/
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#include <time.h>
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#include <string.h>
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#include <rtthread.h>
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static struct rt_device random_dev;
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static unsigned long seed;
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static rt_uint16_t calc_random(void)
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{
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seed = 214013L * seed + 2531011L;
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return (seed >> 16) & 0x7FFF; /* return bits 16~30 */
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}
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static rt_ssize_t random_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
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{
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rt_uint16_t rand = calc_random();
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ssize_t ret = sizeof(rand);
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rt_memcpy(buffer, &rand, ret);
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return ret;
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}
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static rt_ssize_t random_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
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{
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ssize_t ret = sizeof(seed);
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rt_memcpy(&seed, buffer, ret);
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return ret;
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}
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static rt_err_t random_control(rt_device_t dev, int cmd, void *args)
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{
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return RT_EOK;
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}
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#ifdef RT_USING_DEVICE_OPS
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const static struct rt_device_ops random_ops =
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{
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RT_NULL,
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RT_NULL,
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RT_NULL,
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random_read,
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random_write,
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random_control
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};
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#endif
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int random_device_init(void)
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{
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static rt_bool_t init_ok = RT_FALSE;
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if (init_ok)
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{
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return 0;
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}
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RT_ASSERT(!rt_device_find("random"));
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random_dev.type = RT_Device_Class_Miscellaneous;
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#ifdef RT_USING_DEVICE_OPS
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random_dev.ops = &random_ops;
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#else
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random_dev.init = RT_NULL;
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random_dev.open = RT_NULL;
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random_dev.close = RT_NULL;
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random_dev.read = random_read;
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random_dev.write = random_write;
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random_dev.control = random_control;
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#endif
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/* no private */
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random_dev.user_data = RT_NULL;
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rt_device_register(&random_dev, "random", RT_DEVICE_FLAG_RDWR);
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init_ok = RT_TRUE;
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return 0;
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}
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INIT_DEVICE_EXPORT(random_device_init);
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static struct rt_device urandom_dev;
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static unsigned long useed;
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static rt_uint16_t calc_urandom(void)
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{
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useed = 214013L * useed + 2531011L;
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return (useed >> 16) & 0x7FFF; /* return bits 16~30 */
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}
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static rt_ssize_t random_uread(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
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{
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rt_uint16_t rand = calc_urandom();
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ssize_t ret = sizeof(rand);
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rt_memcpy(buffer, &rand, ret);
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return ret;
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}
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static rt_ssize_t random_uwrite(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
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{
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ssize_t ret = sizeof(useed);
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rt_memcpy(&useed, buffer, ret);
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return ret;
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}
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static rt_err_t random_ucontrol(rt_device_t dev, int cmd, void *args)
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{
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return RT_EOK;
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}
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#ifdef RT_USING_DEVICE_OPS
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const static struct rt_device_ops urandom_ops =
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{
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RT_NULL,
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RT_NULL,
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RT_NULL,
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random_uread,
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random_uwrite,
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random_ucontrol
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};
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#endif
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int urandom_device_init(void)
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{
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static rt_bool_t init_ok = RT_FALSE;
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if (init_ok)
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{
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return 0;
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}
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RT_ASSERT(!rt_device_find("urandom"));
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urandom_dev.type = RT_Device_Class_Miscellaneous;
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#ifdef RT_USING_DEVICE_OPS
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urandom_dev.ops = &urandom_ops;
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#else
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urandom_dev.init = RT_NULL;
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urandom_dev.open = RT_NULL;
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urandom_dev.close = RT_NULL;
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urandom_dev.read = random_uread;
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urandom_dev.write = random_uwrite;
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urandom_dev.control = random_ucontrol;
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#endif
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/* no private */
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urandom_dev.user_data = RT_NULL;
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rt_device_register(&urandom_dev, "urandom", RT_DEVICE_FLAG_RDWR);
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init_ok = RT_TRUE;
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return 0;
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}
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INIT_DEVICE_EXPORT(urandom_device_init);
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