85 lines
2.3 KiB
C
85 lines
2.3 KiB
C
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#include <arpa/inet.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <sys/socket.h>
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struct TokenizedQuerry {
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int left;
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char operand;
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int right;
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};
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void handle_arguments(int argc, char *argv[]) {
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if (argc != 2) {
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fprintf(stderr, "Usage: %s PORT\n", argv[0]);
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exit(EXIT_FAILURE);
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}
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}
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struct TokenizedQuerry tokenize(const char *querry) {
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struct TokenizedQuerry tokenized_querry;
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printf("QUERRY: %s\n", querry);
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char left[50], *operand_ptr, right[50];
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char valid_operands[4] = {'+', '-', '/', '*'};
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for (int i = 0; i < sizeof(valid_operands); ++i) {
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operand_ptr = strchr(querry, valid_operands[i]);
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if (operand_ptr != NULL) break;
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}
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if (operand_ptr == NULL) {
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fprintf(stderr, "Wrong operand!\n");
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exit(EXIT_FAILURE);
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}
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int left_length = operand_ptr - querry;
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strncpy(left, querry, left_length);
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strcpy(right, querry + left_length + 1);
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printf("Tokenized: %s %c %s\n", left, *operand_ptr, right);
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tokenized_querry.left = strtol(left, NULL, 10);
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tokenized_querry.operand = *operand_ptr;
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return tokenized_querry;
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}
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void run_server(int port) {
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int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
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if (sockfd < 0) {
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fprintf(stderr, "socket: ");
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exit(EXIT_FAILURE);
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}
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struct sockaddr_in serv_addr, client_addr;
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memset(&serv_addr, 0, sizeof(serv_addr));
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memset(&client_addr, 0, sizeof(client_addr));
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serv_addr.sin_family = AF_INET;
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serv_addr.sin_port = htons(port);
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serv_addr.sin_addr.s_addr = INADDR_ANY;
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int rv = bind(sockfd, (const struct sockaddr *)&serv_addr, sizeof(serv_addr));
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if (rv < 0) {
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fprintf(stderr, "bind: ");
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exit(EXIT_FAILURE);
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}
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char buffer[100];
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memset(&buffer, 0, sizeof(buffer));
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socklen_t client_addr_len;
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struct TokenizedQuerry tokenized_querry;
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while (1) {
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rv = recvfrom(sockfd, buffer, sizeof(buffer), 0, (struct sockaddr *)&client_addr, &client_addr_len);
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tokenized_querry = tokenize(buffer);
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//rv = sendto(sockfd, response, sizeof(response), 0, (const struct sockaddr *)&client_addr, sizeof(client_addr));
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memset(&buffer, 0, sizeof(buffer));
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}
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}
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int main(int argc, char *argv[]) {
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handle_arguments(argc, argv);
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run_server(strtol(argv[1], NULL, 10));
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return 0;
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}
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