Test TiDB `SEND_LONG_LONG` protocol implementation

main.c

#include <mysql/mysql.h>
#include <stdio.h>
#include <string.h>

int insert_with_config(char* encoding, bool send_with_long) {
    MYSQL *con = mysql_init(NULL);
    if (con == NULL) {
        fprintf(stderr, "%s\n", mysql_error(con));
        return 1;
    }
    if (encoding != NULL) {
        if(mysql_set_character_set(con, encoding)) {
            return 1;
        }
    }
    

    if (mysql_real_connect(con, "127.0.0.1", "root", "", 
          "test", 4000, NULL, 0) == NULL) {
        fprintf(stderr, "%s\n", mysql_error(con));
        mysql_close(con);
        return 1;
    }  

    MYSQL_STMT *stmt = mysql_stmt_init(con);
    if (stmt == NULL) {
        fprintf(stderr, "mysql_stmt_init(), out of memory\n");
        return 1;
    }

    char* query = "INSERT INTO t VALUES (?, ?, cast(? as JSON), ?)";
    if (mysql_stmt_prepare(stmt, query, strlen(query))) {
        fprintf(stderr, "mysql_stmt_prepare(), SELECT failed\n");
        fprintf(stderr, "%s\n", mysql_stmt_error(stmt));
        return 1;
    }

    MYSQL_BIND bind[4];
    memset(bind, 0, sizeof(bind));

    int encoding_length = strlen(encoding);
    bind[0].buffer_type = MYSQL_TYPE_STRING;
    bind[0].buffer = (char *)encoding;
    bind[0].is_null = 0;
    bind[0].buffer_length = strlen(encoding);

    char *param1 = "\"你好\"";
    unsigned long str_length1 = strlen(param1);

    for (int i = 1;i<=2;i++) {
        bind[i].buffer_type = MYSQL_TYPE_STRING;
        bind[i].buffer = (char *)param1;
        bind[i].is_null = 0;
        bind[i].buffer_length = str_length1;
        bind[i].length = &str_length1;
    }

    bind[3].buffer_type = MYSQL_TYPE_BLOB;
    bind[3].buffer = (char *)param1;
    bind[3].is_null = 0;
    bind[3].buffer_length = str_length1;
    bind[3].length = &str_length1;

    if (mysql_stmt_bind_param(stmt, bind)) {
        fprintf(stderr, "mysql_stmt_bind_param() failed\n");
        fprintf(stderr, "%s\n", mysql_stmt_error(stmt));
        return 1;
    }

    if (send_with_long) {
        mysql_stmt_send_long_data(stmt, 0, encoding, encoding_length);
        mysql_stmt_send_long_data(stmt, 1, param1, str_length1);
        mysql_stmt_send_long_data(stmt, 2, param1, str_length1);
        mysql_stmt_send_long_data(stmt, 3, param1, str_length1);
    }

    if (mysql_stmt_execute(stmt)) {
        fprintf(stderr, "mysql_stmt_execute, 1 failed\n");
        fprintf(stderr, "%s\n", mysql_stmt_error(stmt));
        return 1;
    }

    mysql_stmt_close(stmt);
    mysql_close(con);

    return 0;
}

// create table t (encoding VARCHAR(16), t TEXT, j JSON, b BLOB);
// Compile with `gcc -o main main.c -lmysqlclient`
int main() {
    int ret = insert_with_config("utf8", false);
    if (ret != 0) {
        return ret;
    }
    ret = insert_with_config("utf8", true);
    if (ret != 0) {
        return ret;
    }
    ret = insert_with_config("gbk", false);
    if (ret != 0) {
        return ret;
    }
    ret = insert_with_config("gbk", true);
    if (ret != 0) {
        return ret;
    }
}

Running this script needs an existing table:

create table t (encoding VARCHAR(16), t TEXT, j JSON, b BLOB);

You can compile this program with:

gcc -o main main.c -lmysqlclient