CentOS7下编译安装libmodbus库
下载libdmodbus源代码
libmodbus官网下载页面如下图所示：
可以从如下链接下载libmodbus源代码
- libmodbus-3.1.6.tar.gz
-
libmodbus-3.0.8.tar.gz
当然也可以直接从github上面克隆源代码到本地
git clone https://github.com/stephane/libmodbus.git 复制
下载后的源代码目录如下图所示：
编译安装lidmodbus
关于如何安装libmodbus在上面已经说得很清楚了：
在
libmodbus
根目录下直接运行下面的命令编译、安装
libmodbus
库
./autogen.sh
./configure
make
make install 复制
相关编译安装过程如下图所示：
可以看到默认情况下libmodbus的头文件被放到/usr/local/include目录下，动态库文件放到/usr/local/lib目录下。
至此，CentOS7下的libmodbus编译和安装就完成了。
测试
关于libmodbus的一些测试，Github上面也描述得比较清楚了：
libmodbus
官网提供的一些测试示例如下图所示：
- libmodbus/tests/unit-test-server.c
/*
* Copyright © 2008-2014 Stéphane Raimbault <[email protected]>
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <modbus.h>
#ifdef _WIN32
# include <winsock2.h>
#else
# include <sys/socket.h>
#endif
/* For MinGW */
#ifndef MSG_NOSIGNAL
# define MSG_NOSIGNAL 0
#endif
#include "unit-test.h"
enum {
TCP,
TCP_PI,
RTU
};
int main(int argc, char*argv[])
{
int s = -1;
modbus_t *ctx;
modbus_mapping_t *mb_mapping;
int rc;
int i;
int use_backend;
uint8_t *query;
int header_length;
if (argc > 1) {
if (strcmp(argv[1], "tcp") == 0) {
use_backend = TCP;
} else if (strcmp(argv[1], "tcppi") == 0) {
use_backend = TCP_PI;
} else if (strcmp(argv[1], "rtu") == 0) {
use_backend = RTU;
} else {
printf("Usage:\n %s [tcp|tcppi|rtu] - Modbus server for unit testing\n\n", argv[0]);
return -1;
}
} else {
/* By default */
use_backend = TCP;
}
if (use_backend == TCP) {
ctx = modbus_new_tcp("127.0.0.1", 1502);
query = malloc(MODBUS_TCP_MAX_ADU_LENGTH);
} else if (use_backend == TCP_PI) {
ctx = modbus_new_tcp_pi("::0", "1502");
query = malloc(MODBUS_TCP_MAX_ADU_LENGTH);
} else {
ctx = modbus_new_rtu("/dev/ttyUSB0", 115200, 'N', 8, 1);
modbus_set_slave(ctx, SERVER_ID);
query = malloc(MODBUS_RTU_MAX_ADU_LENGTH);
}
header_length = modbus_get_header_length(ctx);
modbus_set_debug(ctx, TRUE);
mb_mapping = modbus_mapping_new_start_address(
UT_BITS_ADDRESS, UT_BITS_NB,
UT_INPUT_BITS_ADDRESS, UT_INPUT_BITS_NB,
UT_REGISTERS_ADDRESS, UT_REGISTERS_NB_MAX,
UT_INPUT_REGISTERS_ADDRESS, UT_INPUT_REGISTERS_NB);
if (mb_mapping == NULL) {
fprintf(stderr, "Failed to allocate the mapping: %s\n",
modbus_strerror(errno));
modbus_free(ctx);
return -1;
}
/* Examples from PI_MODBUS_300.pdf.
Only the read-only input values are assigned. */
/* Initialize input values that's can be only done server side. */
modbus_set_bits_from_bytes(mb_mapping->tab_input_bits, 0, UT_INPUT_BITS_NB,
UT_INPUT_BITS_TAB);
/* Initialize values of INPUT REGISTERS */
for (i=0; i < UT_INPUT_REGISTERS_NB; i++) {
mb_mapping->tab_input_registers[i] = UT_INPUT_REGISTERS_TAB[i];;
}
if (use_backend == TCP) {
s = modbus_tcp_listen(ctx, 1);
modbus_tcp_accept(ctx, &s);
} else if (use_backend == TCP_PI) {
s = modbus_tcp_pi_listen(ctx, 1);
modbus_tcp_pi_accept(ctx, &s);
} else {
rc = modbus_connect(ctx);
if (rc == -1) {
fprintf(stderr, "Unable to connect %s\n", modbus_strerror(errno));
modbus_free(ctx);
return -1;
}
}
for (;;) {
do {
rc = modbus_receive(ctx, query);
/* Filtered queries return 0 */
} while (rc == 0);
/* The connection is not closed on errors which require on reply such as
bad CRC in RTU. */
if (rc == -1 && errno != EMBBADCRC) {
/* Quit */
break;
}
/* Special server behavior to test client */
if (query[header_length] == 0x03) {
/* Read holding registers */
if (MODBUS_GET_INT16_FROM_INT8(query, header_length + 3)
== UT_REGISTERS_NB_SPECIAL) {
printf("Set an incorrect number of values\n");
MODBUS_SET_INT16_TO_INT8(query, header_length + 3,
UT_REGISTERS_NB_SPECIAL - 1);
} else if (MODBUS_GET_INT16_FROM_INT8(query, header_length + 1)
== UT_REGISTERS_ADDRESS_SPECIAL) {
printf("Reply to this special register address by an exception\n");
modbus_reply_exception(ctx, query,
MODBUS_EXCEPTION_SLAVE_OR_SERVER_BUSY);
continue;
} else if (MODBUS_GET_INT16_FROM_INT8(query, header_length + 1)
== UT_REGISTERS_ADDRESS_INVALID_TID_OR_SLAVE) {
const int RAW_REQ_LENGTH = 5;
uint8_t raw_req[] = {
(use_backend == RTU) ? INVALID_SERVER_ID : 0xFF,
0x03,
0x02, 0x00, 0x00
};
printf("Reply with an invalid TID or slave\n");
modbus_send_raw_request(ctx, raw_req, RAW_REQ_LENGTH * sizeof(uint8_t));
continue;
} else if (MODBUS_GET_INT16_FROM_INT8(query, header_length + 1)
== UT_REGISTERS_ADDRESS_SLEEP_500_MS) {
printf("Sleep 0.5 s before replying\n");
usleep(500000);
} else if (MODBUS_GET_INT16_FROM_INT8(query, header_length + 1)
== UT_REGISTERS_ADDRESS_BYTE_SLEEP_5_MS) {
/* Test low level only available in TCP mode */
/* Catch the reply and send reply byte a byte */
uint8_t req[] = "\x00\x1C\x00\x00\x00\x05\xFF\x03\x02\x00\x00";
int req_length = 11;
int w_s = modbus_get_socket(ctx);
if (w_s == -1) {
fprintf(stderr, "Unable to get a valid socket in special test\n");
continue;
}
/* Copy TID */
req[1] = query[1];
for (i=0; i < req_length; i++) {
printf("(%.2X)", req[i]);
usleep(5000);
rc = send(w_s, (const char*)(req + i), 1, MSG_NOSIGNAL);
if (rc == -1) {
break;
}
}
continue;
}
}
rc = modbus_reply(ctx, query, rc, mb_mapping);
if (rc == -1) {
break;
}
}
printf("Quit the loop: %s\n", modbus_strerror(errno));
if (use_backend == TCP) {
if (s != -1) {
close(s);
}
}
modbus_mapping_free(mb_mapping);
free(query);
/* For RTU */
modbus_close(ctx);
modbus_free(ctx);
return 0;
} 复制
- libmodbus/tests/unit-test-client.c
/*
* Copyright © 2008-2014 Stéphane Raimbault <[email protected]>
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <modbus.h>
#include "unit-test.h"
const int EXCEPTION_RC = 2;
enum {
TCP,
TCP_PI,
RTU
};
int test_server(modbus_t *ctx, int use_backend);
int send_crafted_request(modbus_t *ctx, int function,
uint8_t *req, int req_size,
uint16_t max_value, uint16_t bytes,
int backend_length, int backend_offset);
int equal_dword(uint16_t *tab_reg, const uint32_t value);
#define BUG_REPORT(_cond, _format, _args ...) \
printf("\nLine %d: assertion error for '%s': " _format "\n", __LINE__, # _cond, ## _args)
#define ASSERT_TRUE(_cond, _format, __args...) { \
if (_cond) { \
printf("OK\n"); \
} else { \
BUG_REPORT(_cond, _format, ## __args); \
goto close; \
} \
};
int equal_dword(uint16_t *tab_reg, const uint32_t value) {
return ((tab_reg[0] == (value >> 16)) && (tab_reg[1] == (value & 0xFFFF)));
}
int main(int argc, char *argv[])
{
const int NB_REPORT_SLAVE_ID = 10;
uint8_t *tab_rp_bits = NULL;
uint16_t *tab_rp_registers = NULL;
uint16_t *tab_rp_registers_bad = NULL;
modbus_t *ctx = NULL;
int i;
uint8_t value;
int nb_points;
int rc;
float real;
uint32_t old_response_to_sec;
uint32_t old_response_to_usec;
uint32_t new_response_to_sec;
uint32_t new_response_to_usec;
uint32_t old_byte_to_sec;
uint32_t old_byte_to_usec;
int use_backend;
int success = FALSE;
int old_slave;
if (argc > 1) {
if (strcmp(argv[1], "tcp") == 0) {
use_backend = TCP;
} else if (strcmp(argv[1], "tcppi") == 0) {
use_backend = TCP_PI;
} else if (strcmp(argv[1], "rtu") == 0) {
use_backend = RTU;
} else {
printf("Usage:\n %s [tcp|tcppi|rtu] - Modbus client for unit testing\n\n", argv[0]);
exit(1);
}
} else {
/* By default */
use_backend = TCP;
}
if (use_backend == TCP) {
ctx = modbus_new_tcp("127.0.0.1", 1502);
} else if (use_backend == TCP_PI) {
ctx = modbus_new_tcp_pi("::1", "1502");
} else {
ctx = modbus_new_rtu("/dev/ttyUSB1", 115200, 'N', 8, 1);
}
if (ctx == NULL) {
fprintf(stderr, "Unable to allocate libmodbus context\n");
return -1;
}
modbus_set_debug(ctx, TRUE);
modbus_set_error_recovery(ctx,
MODBUS_ERROR_RECOVERY_LINK |
MODBUS_ERROR_RECOVERY_PROTOCOL);
if (use_backend == RTU) {
modbus_set_slave(ctx, SERVER_ID);
}
modbus_get_response_timeout(ctx, &old_response_to_sec, &old_response_to_usec);
if (modbus_connect(ctx) == -1) {
fprintf(stderr, "Connection failed: %s\n", modbus_strerror(errno));
modbus_free(ctx);
return -1;
}
modbus_get_response_timeout(ctx, &new_response_to_sec, &new_response_to_usec);
printf("** UNIT TESTING **\n");
printf("1/1 No response timeout modification on connect: ");
ASSERT_TRUE(old_response_to_sec == new_response_to_sec &&
old_response_to_usec == new_response_to_usec, "");
/* Allocate and initialize the memory to store the bits */
nb_points = (UT_BITS_NB > UT_INPUT_BITS_NB) ? UT_BITS_NB : UT_INPUT_BITS_NB;
tab_rp_bits = (uint8_t *) malloc(nb_points * sizeof(uint8_t));
memset(tab_rp_bits, 0, nb_points * sizeof(uint8_t));
/* Allocate and initialize the memory to store the registers */
nb_points = (UT_REGISTERS_NB > UT_INPUT_REGISTERS_NB) ?
UT_REGISTERS_NB : UT_INPUT_REGISTERS_NB;
tab_rp_registers = (uint16_t *) malloc(nb_points * sizeof(uint16_t));
memset(tab_rp_registers, 0, nb_points * sizeof(uint16_t));
printf("\nTEST WRITE/READ:\n");
/** COIL BITS **/
/* Single */
rc = modbus_write_bit(ctx, UT_BITS_ADDRESS, ON);
printf("1/2 modbus_write_bit: ");
ASSERT_TRUE(rc == 1, "");
rc = modbus_read_bits(ctx, UT_BITS_ADDRESS, 1, tab_rp_bits);
printf("2/2 modbus_read_bits: ");
ASSERT_TRUE(rc == 1, "FAILED (nb points %d)\n", rc);
ASSERT_TRUE(tab_rp_bits[0] == ON, "FAILED (%0X != %0X)\n",
tab_rp_bits[0], ON);
/* End single */
/* Multiple bits */
{
uint8_t tab_value[UT_BITS_NB];
modbus_set_bits_from_bytes(tab_value, 0, UT_BITS_NB, UT_BITS_TAB);
rc = modbus_write_bits(ctx, UT_BITS_ADDRESS, UT_BITS_NB, tab_value);
printf("1/2 modbus_write_bits: ");
ASSERT_TRUE(rc == UT_BITS_NB, "");
}
rc = modbus_read_bits(ctx, UT_BITS_ADDRESS, UT_BITS_NB, tab_rp_bits);
printf("2/2 modbus_read_bits: ");
ASSERT_TRUE(rc == UT_BITS_NB, "FAILED (nb points %d)\n", rc);
i = 0;
nb_points = UT_BITS_NB;
while (nb_points > 0) {
int nb_bits = (nb_points > 8) ? 8 : nb_points;
value = modbus_get_byte_from_bits(tab_rp_bits, i*8, nb_bits);
ASSERT_TRUE(value == UT_BITS_TAB[i], "FAILED (%0X != %0X)\n",
value, UT_BITS_TAB[i]);
nb_points -= nb_bits;
i++;
}
printf("OK\n");
/* End of multiple bits */
/** DISCRETE INPUTS **/
rc = modbus_read_input_bits(ctx, UT_INPUT_BITS_ADDRESS,
UT_INPUT_BITS_NB, tab_rp_bits);
printf("1/1 modbus_read_input_bits: ");
ASSERT_TRUE(rc == UT_INPUT_BITS_NB, "FAILED (nb points %d)\n", rc);
i = 0;
nb_points = UT_INPUT_BITS_NB;
while (nb_points > 0) {
int nb_bits = (nb_points > 8) ? 8 : nb_points;
value = modbus_get_byte_from_bits(tab_rp_bits, i*8, nb_bits);
ASSERT_TRUE(value == UT_INPUT_BITS_TAB[i], "FAILED (%0X != %0X)\n",
value, UT_INPUT_BITS_TAB[i]);
nb_points -= nb_bits;
i++;
}
printf("OK\n");
/** HOLDING REGISTERS **/
/* Single register */
rc = modbus_write_register(ctx, UT_REGISTERS_ADDRESS, 0x1234);
printf("1/2 modbus_write_register: ");
ASSERT_TRUE(rc == 1, "");
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS,
1, tab_rp_registers);
printf("2/2 modbus_read_registers: ");
ASSERT_TRUE(rc == 1, "FAILED (nb points %d)\n", rc);
ASSERT_TRUE(tab_rp_registers[0] == 0x1234, "FAILED (%0X != %0X)\n",
tab_rp_registers[0], 0x1234);
/* End of single register */
/* Many registers */
rc = modbus_write_registers(ctx, UT_REGISTERS_ADDRESS,
UT_REGISTERS_NB, UT_REGISTERS_TAB);
printf("1/5 modbus_write_registers: ");
ASSERT_TRUE(rc == UT_REGISTERS_NB, "");
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS,
UT_REGISTERS_NB, tab_rp_registers);
printf("2/5 modbus_read_registers: ");
ASSERT_TRUE(rc == UT_REGISTERS_NB, "FAILED (nb points %d)\n", rc);
for (i=0; i < UT_REGISTERS_NB; i++) {
ASSERT_TRUE(tab_rp_registers[i] == UT_REGISTERS_TAB[i],
"FAILED (%0X != %0X)\n",
tab_rp_registers[i], UT_REGISTERS_TAB[i]);
}
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS,
0, tab_rp_registers);
printf("3/5 modbus_read_registers (0): ");
ASSERT_TRUE(rc == -1, "FAILED (nb_points %d)\n", rc);
nb_points = (UT_REGISTERS_NB >
UT_INPUT_REGISTERS_NB) ?
UT_REGISTERS_NB : UT_INPUT_REGISTERS_NB;
memset(tab_rp_registers, 0, nb_points * sizeof(uint16_t));
/* Write registers to zero from tab_rp_registers and store read registers
into tab_rp_registers. So the read registers must set to 0, except the
first one because there is an offset of 1 register on write. */
rc = modbus_write_and_read_registers(ctx,
UT_REGISTERS_ADDRESS + 1,
UT_REGISTERS_NB - 1,
tab_rp_registers,
UT_REGISTERS_ADDRESS,
UT_REGISTERS_NB,
tab_rp_registers);
printf("4/5 modbus_write_and_read_registers: ");
ASSERT_TRUE(rc == UT_REGISTERS_NB, "FAILED (nb points %d != %d)\n",
rc, UT_REGISTERS_NB);
ASSERT_TRUE(tab_rp_registers[0] == UT_REGISTERS_TAB[0],
"FAILED (%0X != %0X)\n",
tab_rp_registers[0], UT_REGISTERS_TAB[0]);
for (i=1; i < UT_REGISTERS_NB; i++) {
ASSERT_TRUE(tab_rp_registers[i] == 0, "FAILED (%0X != %0X)\n",
tab_rp_registers[i], 0);
}
/* End of many registers */
/** INPUT REGISTERS **/
rc = modbus_read_input_registers(ctx, UT_INPUT_REGISTERS_ADDRESS,
UT_INPUT_REGISTERS_NB,
tab_rp_registers);
printf("1/1 modbus_read_input_registers: ");
ASSERT_TRUE(rc == UT_INPUT_REGISTERS_NB, "FAILED (nb points %d)\n", rc);
for (i=0; i < UT_INPUT_REGISTERS_NB; i++) {
ASSERT_TRUE(tab_rp_registers[i] == UT_INPUT_REGISTERS_TAB[i],
"FAILED (%0X != %0X)\n",
tab_rp_registers[i], UT_INPUT_REGISTERS_TAB[i]);
}
/* MASKS */
printf("1/1 Write mask: ");
rc = modbus_write_register(ctx, UT_REGISTERS_ADDRESS, 0x12);
rc = modbus_mask_write_register(ctx, UT_REGISTERS_ADDRESS, 0xF2, 0x25);
ASSERT_TRUE(rc != -1, "FAILED (%x == -1)\n", rc);
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS, 1, tab_rp_registers);
ASSERT_TRUE(tab_rp_registers[0] == 0x17,
"FAILED (%0X != %0X)\n",
tab_rp_registers[0], 0x17);
printf("\nTEST FLOATS\n");
/** FLOAT **/
printf("1/4 Set/get float ABCD: ");
modbus_set_float_abcd(UT_REAL, tab_rp_registers);
ASSERT_TRUE(equal_dword(tab_rp_registers, UT_IREAL_ABCD), "FAILED Set float ABCD");
real = modbus_get_float_abcd(tab_rp_registers);
ASSERT_TRUE(real == UT_REAL, "FAILED (%f != %f)\n", real, UT_REAL);
printf("2/4 Set/get float DCBA: ");
modbus_set_float_dcba(UT_REAL, tab_rp_registers);
ASSERT_TRUE(equal_dword(tab_rp_registers, UT_IREAL_DCBA), "FAILED Set float DCBA");
real = modbus_get_float_dcba(tab_rp_registers);
ASSERT_TRUE(real == UT_REAL, "FAILED (%f != %f)\n", real, UT_REAL);
printf("3/4 Set/get float BADC: ");
modbus_set_float_badc(UT_REAL, tab_rp_registers);
ASSERT_TRUE(equal_dword(tab_rp_registers, UT_IREAL_BADC), "FAILED Set float BADC");
real = modbus_get_float_badc(tab_rp_registers);
ASSERT_TRUE(real == UT_REAL, "FAILED (%f != %f)\n", real, UT_REAL);
printf("4/4 Set/get float CDAB: ");
modbus_set_float_cdab(UT_REAL, tab_rp_registers);
ASSERT_TRUE(equal_dword(tab_rp_registers, UT_IREAL_CDAB), "FAILED Set float CDAB");
real = modbus_get_float_cdab(tab_rp_registers);
ASSERT_TRUE(real == UT_REAL, "FAILED (%f != %f)\n", real, UT_REAL);
printf("\nAt this point, error messages doesn't mean the test has failed\n");
/** ILLEGAL DATA ADDRESS **/
printf("\nTEST ILLEGAL DATA ADDRESS:\n");
/* The mapping begins at the defined addresses and ends at address +
* nb_points so these addresses are not valid. */
rc = modbus_read_bits(ctx, 0, 1, tab_rp_bits);
printf("* modbus_read_bits (0): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_read_bits(ctx, UT_BITS_ADDRESS, UT_BITS_NB + 1, tab_rp_bits);
printf("* modbus_read_bits (max): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_read_input_bits(ctx, 0, 1, tab_rp_bits);
printf("* modbus_read_input_bits (0): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_read_input_bits(ctx, UT_INPUT_BITS_ADDRESS,
UT_INPUT_BITS_NB + 1, tab_rp_bits);
printf("* modbus_read_input_bits (max): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_read_registers(ctx, 0, 1, tab_rp_registers);
printf("* modbus_read_registers (0): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS,
UT_REGISTERS_NB_MAX + 1, tab_rp_registers);
printf("* modbus_read_registers (max): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_read_input_registers(ctx, 0, 1, tab_rp_registers);
printf("* modbus_read_input_registers (0): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_read_input_registers(ctx, UT_INPUT_REGISTERS_ADDRESS,
UT_INPUT_REGISTERS_NB + 1,
tab_rp_registers);
printf("* modbus_read_input_registers (max): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_write_bit(ctx, 0, ON);
printf("* modbus_write_bit (0): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_write_bit(ctx, UT_BITS_ADDRESS + UT_BITS_NB, ON);
printf("* modbus_write_bit (max): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_write_bits(ctx, 0, 1, tab_rp_bits);
printf("* modbus_write_coils (0): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_write_bits(ctx, UT_BITS_ADDRESS + UT_BITS_NB,
UT_BITS_NB, tab_rp_bits);
printf("* modbus_write_coils (max): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_write_register(ctx, 0, tab_rp_registers[0]);
printf("* modbus_write_register (0): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_write_register(ctx, UT_REGISTERS_ADDRESS + UT_REGISTERS_NB_MAX,
tab_rp_registers[0]);
printf("* modbus_write_register (max): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_write_registers(ctx, 0, 1, tab_rp_registers);
printf("* modbus_write_registers (0): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_write_registers(ctx, UT_REGISTERS_ADDRESS + UT_REGISTERS_NB_MAX,
UT_REGISTERS_NB, tab_rp_registers);
printf("* modbus_write_registers (max): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_mask_write_register(ctx, 0, 0xF2, 0x25);
printf("* modbus_mask_write_registers (0): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_mask_write_register(ctx, UT_REGISTERS_ADDRESS + UT_REGISTERS_NB_MAX,
0xF2, 0x25);
printf("* modbus_mask_write_registers (max): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_write_and_read_registers(ctx, 0, 1, tab_rp_registers, 0, 1, tab_rp_registers);
printf("* modbus_write_and_read_registers (0): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
rc = modbus_write_and_read_registers(ctx,
UT_REGISTERS_ADDRESS + UT_REGISTERS_NB_MAX,
UT_REGISTERS_NB, tab_rp_registers,
UT_REGISTERS_ADDRESS + UT_REGISTERS_NB_MAX,
UT_REGISTERS_NB, tab_rp_registers);
printf("* modbus_write_and_read_registers (max): ");
ASSERT_TRUE(rc == -1 && errno == EMBXILADD, "");
/** TOO MANY DATA **/
printf("\nTEST TOO MANY DATA ERROR:\n");
rc = modbus_read_bits(ctx, UT_BITS_ADDRESS,
MODBUS_MAX_READ_BITS + 1, tab_rp_bits);
printf("* modbus_read_bits: ");
ASSERT_TRUE(rc == -1 && errno == EMBMDATA, "");
rc = modbus_read_input_bits(ctx, UT_INPUT_BITS_ADDRESS,
MODBUS_MAX_READ_BITS + 1, tab_rp_bits);
printf("* modbus_read_input_bits: ");
ASSERT_TRUE(rc == -1 && errno == EMBMDATA, "");
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS,
MODBUS_MAX_READ_REGISTERS + 1,
tab_rp_registers);
printf("* modbus_read_registers: ");
ASSERT_TRUE(rc == -1 && errno == EMBMDATA, "");
rc = modbus_read_input_registers(ctx, UT_INPUT_REGISTERS_ADDRESS,
MODBUS_MAX_READ_REGISTERS + 1,
tab_rp_registers);
printf("* modbus_read_input_registers: ");
ASSERT_TRUE(rc == -1 && errno == EMBMDATA, "");
rc = modbus_write_bits(ctx, UT_BITS_ADDRESS,
MODBUS_MAX_WRITE_BITS + 1, tab_rp_bits);
printf("* modbus_write_bits: ");
ASSERT_TRUE(rc == -1 && errno == EMBMDATA, "");
rc = modbus_write_registers(ctx, UT_REGISTERS_ADDRESS,
MODBUS_MAX_WRITE_REGISTERS + 1,
tab_rp_registers);
printf("* modbus_write_registers: ");
ASSERT_TRUE(rc == -1 && errno == EMBMDATA, "");
/** SLAVE REPLY **/
old_slave = modbus_get_slave(ctx);
printf("\nTEST SLAVE REPLY:\n");
modbus_set_slave(ctx, INVALID_SERVER_ID);
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS,
UT_REGISTERS_NB, tab_rp_registers);
if (use_backend == RTU) {
const int RAW_REQ_LENGTH = 6;
uint8_t raw_req[] = { INVALID_SERVER_ID, 0x03, 0x00, 0x01, 0x01, 0x01 };
/* Too many points */
uint8_t raw_invalid_req[] = { INVALID_SERVER_ID, 0x03, 0x00, 0x01, 0xFF, 0xFF };
const int RAW_RSP_LENGTH = 7;
uint8_t raw_rsp[] = { INVALID_SERVER_ID, 0x03, 0x04, 0, 0, 0, 0 };
uint8_t rsp[MODBUS_RTU_MAX_ADU_LENGTH];
/* No response in RTU mode */
printf("1-A/3 No response from slave %d: ", INVALID_SERVER_ID);
ASSERT_TRUE(rc == -1 && errno == ETIMEDOUT, "");
/* The slave raises a timeout on a confirmation to ignore because if an
* indication for another slave is received, a confirmation must follow */
/* Send a pair of indication/confirmation to the slave with a different
* slave ID to simulate a communication on a RS485 bus. At first, the
* slave will see the indication message then the confirmation, and it must
* ignore both. */
modbus_send_raw_request(ctx, raw_req, RAW_REQ_LENGTH * sizeof(uint8_t));
modbus_send_raw_request(ctx, raw_rsp, RAW_RSP_LENGTH * sizeof(uint8_t));
rc = modbus_receive_confirmation(ctx, rsp);
printf("1-B/3 No response from slave %d on indication/confirmation messages: ",
INVALID_SERVER_ID);
ASSERT_TRUE(rc == -1 && errno == ETIMEDOUT, "");
/* Send an INVALID request for another slave */
modbus_send_raw_request(ctx, raw_invalid_req, RAW_REQ_LENGTH * sizeof(uint8_t));
rc = modbus_receive_confirmation(ctx, rsp);
printf("1-C/3 No response from slave %d with invalid request: ",
INVALID_SERVER_ID);
ASSERT_TRUE(rc == -1 && errno == ETIMEDOUT, "");
rc = modbus_set_slave(ctx, MODBUS_BROADCAST_ADDRESS);
ASSERT_TRUE(rc != -1, "Invalid broadcast address");
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS,
UT_REGISTERS_NB, tab_rp_registers);
printf("2/3 No reply after a broadcast query: ");
ASSERT_TRUE(rc == -1 && errno == ETIMEDOUT, "");
} else {
/* Response in TCP mode */
printf("1/3 Response from slave %d: ", INVALID_SERVER_ID);
ASSERT_TRUE(rc == UT_REGISTERS_NB, "");
rc = modbus_set_slave(ctx, MODBUS_BROADCAST_ADDRESS);
ASSERT_TRUE(rc != -1, "Invalid broacast address");
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS,
UT_REGISTERS_NB, tab_rp_registers);
printf("2/3 Reply after a query with unit id == 0: ");
ASSERT_TRUE(rc == UT_REGISTERS_NB, "");
}
/* Restore slave */
modbus_set_slave(ctx, old_slave);
printf("3/3 Response with an invalid TID or slave: ");
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS_INVALID_TID_OR_SLAVE,
1, tab_rp_registers);
ASSERT_TRUE(rc == -1, "");
printf("1/2 Report slave ID truncated: \n");
/* Set a marker to ensure limit is respected */
tab_rp_bits[NB_REPORT_SLAVE_ID - 1] = 42;
rc = modbus_report_slave_id(ctx, NB_REPORT_SLAVE_ID - 1, tab_rp_bits);
/* Return the size required (response size) but respects the defined limit */
ASSERT_TRUE(rc == NB_REPORT_SLAVE_ID &&
tab_rp_bits[NB_REPORT_SLAVE_ID - 1] == 42,
"Return is rc %d (%d) and marker is %d (42)",
rc, NB_REPORT_SLAVE_ID, tab_rp_bits[NB_REPORT_SLAVE_ID - 1]);
printf("2/2 Report slave ID: \n");
/* tab_rp_bits is used to store bytes */
rc = modbus_report_slave_id(ctx, NB_REPORT_SLAVE_ID, tab_rp_bits);
ASSERT_TRUE(rc == NB_REPORT_SLAVE_ID, "");
/* Slave ID is an arbitraty number for libmodbus */
ASSERT_TRUE(rc > 0, "");
/* Run status indicator is ON */
ASSERT_TRUE(rc > 1 && tab_rp_bits[1] == 0xFF, "");
/* Print additional data as string */
if (rc > 2) {
printf("Additional data: ");
for (i=2; i < rc; i++) {
printf("%c", tab_rp_bits[i]);
}
printf("\n");
}
/* Save original timeout */
modbus_get_response_timeout(ctx, &old_response_to_sec, &old_response_to_usec);
modbus_get_byte_timeout(ctx, &old_byte_to_sec, &old_byte_to_usec);
rc = modbus_set_response_timeout(ctx, 0, 0);
printf("1/6 Invalid response timeout (zero): ");
ASSERT_TRUE(rc == -1 && errno == EINVAL, "");
rc = modbus_set_response_timeout(ctx, 0, 1000000);
printf("2/6 Invalid response timeout (too large us): ");
ASSERT_TRUE(rc == -1 && errno == EINVAL, "");
rc = modbus_set_byte_timeout(ctx, 0, 1000000);
printf("3/6 Invalid byte timeout (too large us): ");
ASSERT_TRUE(rc == -1 && errno == EINVAL, "");
modbus_set_response_timeout(ctx, 0, 1);
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS,
UT_REGISTERS_NB, tab_rp_registers);
printf("4/6 1us response timeout: ");
if (rc == -1 && errno == ETIMEDOUT) {
printf("OK\n");
} else {
printf("FAILED (can fail on some platforms)\n");
}
/* A wait and flush operation is done by the error recovery code of
* libmodbus but after a sleep of current response timeout
* so 0 can be too short!
*/
usleep(old_response_to_sec * 1000000 + old_response_to_usec);
modbus_flush(ctx);
/* Trigger a special behaviour on server to wait for 0.5 second before
* replying whereas allowed timeout is 0.2 second */
modbus_set_response_timeout(ctx, 0, 200000);
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS_SLEEP_500_MS,
1, tab_rp_registers);
printf("5/6 Too short response timeout (0.2s < 0.5s): ");
ASSERT_TRUE(rc == -1 && errno == ETIMEDOUT, "");
/* Wait for reply (0.2 + 0.4 > 0.5 s) and flush before continue */
usleep(400000);
modbus_flush(ctx);
modbus_set_response_timeout(ctx, 0, 600000);
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS_SLEEP_500_MS,
1, tab_rp_registers);
printf("6/6 Adequate response timeout (0.6s > 0.5s): ");
ASSERT_TRUE(rc == 1, "");
/* Disable the byte timeout.
The full response must be available in the 600ms interval */
modbus_set_byte_timeout(ctx, 0, 0);
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS_SLEEP_500_MS,
1, tab_rp_registers);
printf("7/7 Disable byte timeout: ");
ASSERT_TRUE(rc == 1, "");
/* Restore original response timeout */
modbus_set_response_timeout(ctx, old_response_to_sec,
old_response_to_usec);
if (use_backend == TCP) {
/* The test server is only able to test byte timeouts with the TCP
* backend */
/* Timeout of 3ms between bytes */
modbus_set_byte_timeout(ctx, 0, 3000);
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS_BYTE_SLEEP_5_MS,
1, tab_rp_registers);
printf("1/2 Too small byte timeout (3ms < 5ms): ");
ASSERT_TRUE(rc == -1 && errno == ETIMEDOUT, "");
/* Wait remaing bytes before flushing */
usleep(11 * 5000);
modbus_flush(ctx);
/* Timeout of 7ms between bytes */
modbus_set_byte_timeout(ctx, 0, 7000);
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS_BYTE_SLEEP_5_MS,
1, tab_rp_registers);
printf("2/2 Adapted byte timeout (7ms > 5ms): ");
ASSERT_TRUE(rc == 1, "");
}
/* Restore original byte timeout */
modbus_set_byte_timeout(ctx, old_byte_to_sec, old_byte_to_usec);
/** BAD RESPONSE **/
printf("\nTEST BAD RESPONSE ERROR:\n");
/* Allocate only the required space */
tab_rp_registers_bad = (uint16_t *) malloc(
UT_REGISTERS_NB_SPECIAL * sizeof(uint16_t));
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS,
UT_REGISTERS_NB_SPECIAL, tab_rp_registers_bad);
printf("* modbus_read_registers: ");
ASSERT_TRUE(rc == -1 && errno == EMBBADDATA, "");
free(tab_rp_registers_bad);
/** MANUAL EXCEPTION **/
printf("\nTEST MANUAL EXCEPTION:\n");
rc = modbus_read_registers(ctx, UT_REGISTERS_ADDRESS_SPECIAL,
UT_REGISTERS_NB, tab_rp_registers);
printf("* modbus_read_registers at special address: ");
ASSERT_TRUE(rc == -1 && errno == EMBXSBUSY, "");
/** Run a few tests to challenge the server code **/
if (test_server(ctx, use_backend) == -1) {
goto close;
}
modbus_close(ctx);
modbus_free(ctx);
ctx = NULL;
/* Test init functions */
printf("\nTEST INVALID INITIALIZATION:\n");
ctx = modbus_new_rtu(NULL, 1, 'A', 0, 0);
ASSERT_TRUE(ctx == NULL && errno == EINVAL, "");
ctx = modbus_new_rtu("/dev/dummy", 0, 'A', 0, 0);
ASSERT_TRUE(ctx == NULL && errno == EINVAL, "");
ctx = modbus_new_tcp_pi(NULL, NULL);
ASSERT_TRUE(ctx == NULL && errno == EINVAL, "");
printf("\nALL TESTS PASS WITH SUCCESS.\n");
success = TRUE;
close:
/* Free the memory */
free(tab_rp_bits);
free(tab_rp_registers);
/* Close the connection */
modbus_close(ctx);
modbus_free(ctx);
return (success) ? 0 : -1;
}
/* Send crafted requests to test server resilience
and ensure proper exceptions are returned. */
int test_server(modbus_t *ctx, int use_backend)
{
int rc;
int i;
/* Read requests */
const int READ_RAW_REQ_LEN = 6;
const int slave = (use_backend == RTU) ? SERVER_ID : MODBUS_TCP_SLAVE;
uint8_t read_raw_req[] = {
slave,
/* function, address, 5 values */
MODBUS_FC_READ_HOLDING_REGISTERS,
UT_REGISTERS_ADDRESS >> 8, UT_REGISTERS_ADDRESS & 0xFF,
0x0, 0x05
};
/* Write and read registers request */
const int RW_RAW_REQ_LEN = 13;
uint8_t rw_raw_req[] = {
slave,
/* function, addr to read, nb to read */
MODBUS_FC_WRITE_AND_READ_REGISTERS,
/* Read */
UT_REGISTERS_ADDRESS >> 8, UT_REGISTERS_ADDRESS & 0xFF,
(MODBUS_MAX_WR_READ_REGISTERS + 1) >> 8,
(MODBUS_MAX_WR_READ_REGISTERS + 1) & 0xFF,
/* Write */
0, 0,
0, 1,
/* Write byte count */
1 * 2,
/* One data to write... */
0x12, 0x34
};
const int WRITE_RAW_REQ_LEN = 13;
uint8_t write_raw_req[] = {
slave,
/* function will be set in the loop */
MODBUS_FC_WRITE_MULTIPLE_REGISTERS,
/* Address */
UT_REGISTERS_ADDRESS >> 8, UT_REGISTERS_ADDRESS & 0xFF,
/* 3 values, 6 bytes */
0x00, 0x03, 0x06,
/* Dummy data to write */
0x02, 0x2B, 0x00, 0x01, 0x00, 0x64
};
const int INVALID_FC = 0x42;
const int INVALID_FC_REQ_LEN = 6;
uint8_t invalid_fc_raw_req[] = {
slave, 0x42, 0x00, 0x00, 0x00, 0x00
};
int req_length;
uint8_t rsp[MODBUS_TCP_MAX_ADU_LENGTH];
int tab_read_function[] = {
MODBUS_FC_READ_COILS,
MODBUS_FC_READ_DISCRETE_INPUTS,
MODBUS_FC_READ_HOLDING_REGISTERS,
MODBUS_FC_READ_INPUT_REGISTERS
};
int tab_read_nb_max[] = {
MODBUS_MAX_READ_BITS + 1,
MODBUS_MAX_READ_BITS + 1,
MODBUS_MAX_READ_REGISTERS + 1,
MODBUS_MAX_READ_REGISTERS + 1
};
int backend_length;
int backend_offset;
if (use_backend == RTU) {
backend_length = 3;
backend_offset = 1;
} else {
backend_length = 7;
backend_offset = 7;
}
printf("\nTEST RAW REQUESTS:\n");
uint32_t old_response_to_sec;
uint32_t old_response_to_usec;
/* This requests can generate flushes server side so we need a higher
* response timeout than the server. The server uses the defined response
* timeout to sleep before flushing.
* The old timeouts are restored at the end.
*/
modbus_get_response_timeout(ctx, &old_response_to_sec, &old_response_to_usec);
modbus_set_response_timeout(ctx, 0, 600000);
req_length = modbus_send_raw_request(ctx, read_raw_req, READ_RAW_REQ_LEN);
printf("* modbus_send_raw_request: ");
ASSERT_TRUE(req_length == (backend_length + 5), "FAILED (%d)\n", req_length);
printf("* modbus_receive_confirmation: ");
rc = modbus_receive_confirmation(ctx, rsp);
ASSERT_TRUE(rc == (backend_length + 12), "FAILED (%d)\n", rc);
/* Try to read more values than a response could hold for all data
types. */
for (i=0; i<4; i++) {
rc = send_crafted_request(ctx, tab_read_function[i],
read_raw_req, READ_RAW_REQ_LEN,
tab_read_nb_max[i], 0,
backend_length, backend_offset);
if (rc == -1)
goto close;
}
rc = send_crafted_request(ctx, MODBUS_FC_WRITE_AND_READ_REGISTERS,
rw_raw_req, RW_RAW_REQ_LEN,
MODBUS_MAX_WR_READ_REGISTERS + 1, 0,
backend_length, backend_offset);
if (rc == -1)
goto close;
rc = send_crafted_request(ctx, MODBUS_FC_WRITE_MULTIPLE_REGISTERS,
write_raw_req, WRITE_RAW_REQ_LEN,
MODBUS_MAX_WRITE_REGISTERS + 1, 6,
backend_length, backend_offset);
if (rc == -1)
goto close;
rc = send_crafted_request(ctx, MODBUS_FC_WRITE_MULTIPLE_COILS,
write_raw_req, WRITE_RAW_REQ_LEN,
MODBUS_MAX_WRITE_BITS + 1, 6,
backend_length, backend_offset);
if (rc == -1)
goto close;
/* Modbus write multiple registers with large number of values but a set a
small number of bytes in requests (not nb * 2 as usual). */
rc = send_crafted_request(ctx, MODBUS_FC_WRITE_MULTIPLE_REGISTERS,
write_raw_req, WRITE_RAW_REQ_LEN,
MODBUS_MAX_WRITE_REGISTERS, 6,
backend_length, backend_offset);
if (rc == -1)
goto close;
rc = send_crafted_request(ctx, MODBUS_FC_WRITE_MULTIPLE_COILS,
write_raw_req, WRITE_RAW_REQ_LEN,
MODBUS_MAX_WRITE_BITS, 6,
backend_length, backend_offset);
if (rc == -1)
goto close;
/* Test invalid function code */
modbus_send_raw_request(ctx, invalid_fc_raw_req, INVALID_FC_REQ_LEN * sizeof(uint8_t));
rc = modbus_receive_confirmation(ctx, rsp);
printf("Return an exception on unknown function code: ");
ASSERT_TRUE(rc == (backend_length + EXCEPTION_RC) &&
rsp[backend_offset] == (0x80 + INVALID_FC), "")
modbus_set_response_timeout(ctx, old_response_to_sec, old_response_to_usec);
return 0;
close:
modbus_set_response_timeout(ctx, old_response_to_sec, old_response_to_usec);
return -1;
}
int send_crafted_request(modbus_t *ctx, int function,
uint8_t *req, int req_len,
uint16_t max_value, uint16_t bytes,
int backend_length, int backend_offset)
{
uint8_t rsp[MODBUS_TCP_MAX_ADU_LENGTH];
int j;
for (j=0; j<2; j++) {
int rc;
req[1] = function;
if (j == 0) {
/* Try to read or write zero values on first iteration */
req[4] = 0x00;
req[5] = 0x00;
if (bytes) {
/* Write query */
req[6] = 0x00;
}
} else {
/* Try to read or write max values + 1 on second iteration */
req[4] = (max_value >> 8) & 0xFF;
req[5] = max_value & 0xFF;
if (bytes) {
/* Write query (nb values * 2 to convert in bytes for registers) */
req[6] = bytes;
}
}
modbus_send_raw_request(ctx, req, req_len * sizeof(uint8_t));
if (j == 0) {
printf("* try function 0x%X: %s 0 values: ", function, bytes ? "write": "read");
} else {
printf("* try function 0x%X: %s %d values: ", function, bytes ? "write": "read",
max_value);
}
rc = modbus_receive_confirmation(ctx, rsp);
ASSERT_TRUE(rc == (backend_length + EXCEPTION_RC) &&
rsp[backend_offset] == (0x80 + function) &&
rsp[backend_offset + 1] == MODBUS_EXCEPTION_ILLEGAL_DATA_VALUE, "");
}
return 0;
close:
return -1;
} 复制
在CentOS7下编译安装好libmodbus后，在项目根目录下会多出unit-test-server、unit-test-client这些可执行文件，如下图所示：
使用xshell等终端工具分别打开两个终端，分别运行./unit-test-server和./unit-test-client，如下图所示：
参考资料
- libmodbus官网
- https://libmodbus.org/download/
- https://github.com/stephane/libmodbus