server.c 5.1 KB

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  1. #include <stdio.h>
  2. #include <stdlib.h>
  3. #include <string.h>
  4. #include <unistd.h>
  5. #include <sys/ioctl.h>
  6. #include <sys/types.h>
  7. #include <sys/socket.h>
  8. #include <netinet/in.h>
  9. #include <netinet/tcp.h>
  10. #include <arpa/inet.h>
  11. #define PORT 5000
  12. #define BACKLOG 10
  13. int sockfd;
  14. fd_set read_fds, write_fds;
  15. int fdmax;
  16. struct buffers {
  17. int buf_cnt;
  18. int buf_size;
  19. char *buf;
  20. } buffers[16];
  21. int buf_size = 64;
  22. int int_socket() {
  23. struct sockaddr_in my_addr;
  24. int yes=1;
  25. FD_ZERO(&read_fds);
  26. memset(&my_addr, 0, sizeof(my_addr));
  27. if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
  28. perror("socket");
  29. exit(1);
  30. }
  31. if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)) == -1) {
  32. perror("setsockopt");
  33. exit(1);
  34. }
  35. if(setsockopt(sockfd, IPPROTO_TCP, TCP_NODELAY, &yes, sizeof(int)) < 0) {
  36. perror("setsockopt");
  37. exit(1);
  38. }
  39. //unsigned long one = 1;
  40. if(ioctl(sockfd, FIONBIO, &yes) < 0) {
  41. perror("ioctl");
  42. exit(1);
  43. }
  44. my_addr.sin_family = AF_INET;
  45. my_addr.sin_port = htons(PORT);
  46. my_addr.sin_addr.s_addr = INADDR_ANY;
  47. if (bind(sockfd, (struct sockaddr *)&my_addr, sizeof(struct sockaddr)) == -1) {
  48. perror("bind");
  49. exit(1);
  50. }
  51. if (listen(sockfd, BACKLOG) == -1) {
  52. perror("listen");
  53. exit(1);
  54. }
  55. FD_SET(sockfd, &read_fds);
  56. fdmax = sockfd;
  57. printf("xo: Server socket: %d\n",sockfd);
  58. return 0;
  59. }
  60. int connect_client() {
  61. int sin_size;
  62. int new_fd;
  63. struct sockaddr_in their_addr;
  64. sin_size = sizeof(struct sockaddr_in);
  65. if ((new_fd = accept(sockfd, (struct sockaddr *)&their_addr,&sin_size)) == -1) {
  66. perror("accept");
  67. } else {
  68. FD_SET(new_fd, &read_fds);
  69. if (new_fd > fdmax) {
  70. fdmax = new_fd;
  71. }
  72. buffers[new_fd].buf_size = buf_size;
  73. buffers[new_fd].buf = malloc(buf_size);
  74. printf("xo: new connection from %s on socket %d\n", inet_ntoa(their_addr.sin_addr), new_fd);
  75. }
  76. return 0;
  77. }
  78. int console_input() {
  79. int n;
  80. int arg1;
  81. char *arg2;
  82. printf("console in\n");
  83. arg2 = malloc(16);
  84. buffers[0].buf_cnt = read(0, buffers[0].buf, buffers[0].buf_size);
  85. sscanf(buffers[0].buf, "%d:%s", &arg1 , arg2 );
  86. if ( FD_ISSET( arg1, &read_fds)) {
  87. if ( (send(arg1, buffers[0].buf, buffers[0].buf_cnt, 0)) < 0 )
  88. perror("send");
  89. else
  90. buffers[0].buf_cnt = 0;
  91. }
  92. return 0;
  93. }
  94. int recieve(int rfd) {
  95. char buf[32];
  96. int num_bytes;
  97. if ( rfd == sockfd ) {
  98. connect_client();
  99. return 0;
  100. } else if ( rfd == 0 ) {
  101. console_input();
  102. return 0;
  103. }
  104. if((num_bytes = recv(rfd, buf, sizeof(buf), 0)) <= 0) {
  105. if(num_bytes == 0) {
  106. printf("xo: socket %d exited\n", rfd);
  107. } else {
  108. perror("recv");
  109. }
  110. close(rfd);
  111. FD_CLR(rfd, &read_fds);
  112. } else {
  113. if (( buffers[rfd].buf_cnt + num_bytes ) >= buffers[rfd].buf_size){
  114. buffers[rfd].buf_size = buffers[rfd].buf_size + num_bytes + 2048;
  115. buffers[rfd].buf = (char *) realloc(buffers[rfd].buf, buffers[rfd].buf_size);
  116. }
  117. memcpy(buffers[rfd].buf + buffers[rfd].buf_cnt, buf, num_bytes);
  118. buffers[rfd].buf_cnt += num_bytes ;
  119. }
  120. return 0;
  121. }
  122. int snd(int wfd) {
  123. int n;
  124. if ( FD_ISSET(wfd, &read_fds)) {
  125. if ( wfd != sockfd ) {
  126. if ( (n = send(wfd, buffers[wfd].buf, buffers[wfd].buf_cnt, 0)) < 0 )
  127. perror("send");
  128. else if ( buffers[wfd].buf_cnt == n ) {
  129. FD_CLR(wfd, &write_fds);
  130. buffers[wfd].buf_cnt = 0;
  131. }
  132. else {
  133. memcpy(buffers[wfd].buf, buffers[wfd].buf + n, buffers[wfd].buf_cnt - n);
  134. buffers[wfd].buf_cnt -= n;
  135. }
  136. }
  137. }
  138. return 0;
  139. }
  140. int do_sendrecv() {
  141. int i, j;
  142. struct sockaddr_in their_addr;
  143. fd_set rfds;
  144. FD_ZERO(&rfds);
  145. memcpy(&rfds , &read_fds , sizeof(read_fds));
  146. if ((i = select(fdmax+1, &rfds, &write_fds, NULL, NULL)) == -1) {
  147. perror("select");
  148. exit(1);
  149. }
  150. for(j = 0; j <= fdmax && i > 0; j++) {
  151. if (FD_ISSET(j, &write_fds)) {
  152. snd(j);
  153. i--;
  154. }
  155. if (FD_ISSET(j, &rfds)) {
  156. recieve(j);
  157. i--;
  158. }
  159. }
  160. return 0;
  161. }
  162. int do_parse() {
  163. int i;
  164. for ( i = 1; i <= fdmax; i++) {
  165. if (buffers[i].buf_cnt > 0)
  166. FD_SET(i, &write_fds);
  167. }
  168. return 0;
  169. }
  170. int main(void) {
  171. int_socket();
  172. buffers[0].buf_size = buf_size;
  173. buffers[0].buf = malloc(buf_size);
  174. FD_SET(0,&read_fds);
  175. while(1) {
  176. do_sendrecv();
  177. do_parse();
  178. }
  179. return 0;
  180. }