#include "algo_skel.h" struct naive_ctx { int ref_count; struct buffer_packet bps[10]; GQueue* free_buffer; // Available buffers GHashTable* used_buffer; // Buffers used for reading or writing GQueue* read_waiting; // Who wait to be notified for a read GHashTable* write_waiting; // Structure to track packets waiting to be written }; void on_tcp_read(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo); void on_tcp_write(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo); void on_udp_read(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo); void on_udp_write (struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo); void free_nothing(void* app_ctx) {} void free_naive(void* app_ctx) { struct naive_ctx* ctx = (struct naive_ctx*) app_ctx; ctx->ref_count--; if (ctx->ref_count > 0) return; g_queue_free(ctx->free_buffer); g_queue_free(ctx->read_waiting); g_hash_table_destroy (ctx->used_buffer); free(ctx); } void on_tcp_co(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) { int conn_sock1, conn_sock2; struct sockaddr_in addr; socklen_t in_len; char url[1024], port[6]; struct evt_core_cat local_cat = {0}; struct evt_core_fdinfo to_fdinfo = {0}; to_fdinfo.cat = &local_cat; to_fdinfo.url = url; in_len = sizeof(addr); conn_sock1 = accept(fdinfo->fd, (struct sockaddr*)&addr, &in_len); if (conn_sock1 == -1) goto co_error; conn_sock2 = dup(conn_sock1); if (conn_sock2 == -1) goto co_error; //printf("fd=%d accepts, creating fds=%d,%d\n", fd, conn_sock1, conn_sock2); url_get_port(port, fdinfo->url); to_fdinfo.fd = conn_sock1; to_fdinfo.cat->name = "tcp-read"; sprintf(to_fdinfo.url, "tcp:read:127.0.0.1:%s", port); evt_core_add_fd (ctx, &to_fdinfo); to_fdinfo.fd = conn_sock2; to_fdinfo.cat->name = "tcp-write"; sprintf(to_fdinfo.url, "tcp:write:127.0.0.1:%s", port); evt_core_add_fd (ctx, &to_fdinfo); return; co_error: perror("Failed to handle new connection"); exit(EXIT_FAILURE); } /** * Returns a buffer if available, NULL otherwise */ struct buffer_packet* get_read_buffer(struct naive_ctx *app_ctx, struct evt_core_fdinfo *fdinfo) { struct buffer_packet* bp; // 1. Check if we don't have a buffer bp = g_hash_table_lookup (app_ctx->used_buffer, &fdinfo->fd); if (bp != NULL) return bp; // 2. Get a new buffer otherwise bp = g_queue_pop_head(app_ctx->free_buffer); if (bp == NULL) { // 2.1 If no buffer is available, we subscribe to be notified later g_queue_push_tail (app_ctx->read_waiting, &(fdinfo->fd)); return NULL; } // 3. Update state g_hash_table_insert(app_ctx->used_buffer, &(fdinfo->fd), bp); return bp; } /** * Returns a buffer if available, NULL otherwise */ struct buffer_packet* get_write_buffer(struct naive_ctx *app_ctx, struct evt_core_fdinfo *fdinfo) { struct buffer_packet* bp; GQueue* q; // 1. Check if we don't have a buffer bp = g_hash_table_lookup (app_ctx->used_buffer, &fdinfo->fd); if (bp != NULL) return bp; // 2. Check our waiting queue otherwise if ((q = g_hash_table_lookup(app_ctx->write_waiting, &(fdinfo->fd))) == NULL) return NULL; bp = g_queue_pop_head(q); if (bp == NULL) return NULL; // No packet to process // 3. Update state g_hash_table_insert(app_ctx->used_buffer, &(fdinfo->fd), bp); return bp; } void mv_buffer_rtow(struct naive_ctx* app_ctx, struct evt_core_fdinfo* from, struct evt_core_fdinfo* to, struct buffer_packet* bp) { // 1. We get the target writing queue GQueue* q; q = g_hash_table_lookup(app_ctx->write_waiting, &(to->fd)); if (q == NULL) { q = g_queue_new (); g_hash_table_insert(app_ctx->write_waiting, &(to->fd), q); } // 2. We move the buffer to the target queue g_hash_table_remove(app_ctx->used_buffer, &from->fd); g_queue_push_tail(q, bp); } void mv_buffer_wtor(struct naive_ctx* app_ctx, struct evt_core_fdinfo* fdinfo, struct buffer_packet* bp) { g_queue_push_tail (app_ctx->free_buffer, bp); g_hash_table_remove(app_ctx->used_buffer, &(fdinfo->fd)); } void notify_read(struct evt_core_ctx* ctx, struct naive_ctx* app_ctx) { struct evt_core_fdinfo* next_fdinfo = NULL; while (next_fdinfo == NULL) { int fd = GPOINTER_TO_INT(g_queue_pop_head(app_ctx->read_waiting)); if (fd == 0) break; next_fdinfo = evt_core_get_from_fd (ctx, fd); if (strcmp(next_fdinfo->cat->name, "tcp-read") == 0) on_tcp_read(ctx, next_fdinfo); else if (strcmp(next_fdinfo->cat->name, "udp-read") == 0) on_udp_read(ctx, next_fdinfo); else { fprintf(stderr, "A fd from category %s can't be stored in read_waiting\n", next_fdinfo->cat->name); exit(EXIT_FAILURE); } } } void on_tcp_read(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) { struct buffer_packet* bp; struct evt_core_fdinfo *to_fdinfo = NULL; struct naive_ctx* app_ctx = fdinfo->cat->app_ctx; int read_res = FDS_READY; char url[255]; // 1. Get current read buffer OR a new read buffer OR subscribe to be notified later if ((bp = get_read_buffer(app_ctx, fdinfo)) == NULL) return; // 2. Try to read a whole packet in the buffer while (read_res != FDS_AGAIN && bp->mode == BP_READING) { read_res = read_packet_from_tcp (fdinfo->fd, bp); if (read_res == FDS_ERR) goto co_error; } if (bp->mode != BP_WRITING) return; // 3. A whole packet has been read, we will find someone to write it sprintf(url, "udp:write:127.0.0.1:%d", bp->ip.ap.str.port); to_fdinfo = evt_core_get_from_url (ctx, url); if (to_fdinfo == NULL) { fprintf(stderr, "No fd for URL %s in tcp-read. Dropping packet :( \n", url); mv_buffer_wtor (app_ctx, fdinfo, bp); return; } printf("Pass packet from %s to %s\n", fdinfo->url, url); // 4. We move the buffer and notify the target mv_buffer_rtow (app_ctx, fdinfo, to_fdinfo, bp); on_udp_write(ctx, to_fdinfo); return; co_error: perror("Failed to TCP read"); exit(EXIT_FAILURE); } void on_tcp_write(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) { struct buffer_packet* bp; struct naive_ctx* app_ctx = fdinfo->cat->app_ctx; int write_res = FDS_READY; // 1. Get current write buffer OR a buffer from the waiting queue OR leave if ((bp = get_write_buffer(app_ctx, fdinfo)) == NULL) return; // 2. Write data from the buffer to the socket while (write_res != FDS_AGAIN && bp->mode == BP_WRITING) { write_res = write_packet_to_tcp(fdinfo->fd, bp); if (write_res == FDS_ERR) goto co_error; } if (bp->mode != BP_READING) return; // 3. A whole packet has been written // Release the buffer and notify mv_buffer_wtor(app_ctx, fdinfo, bp); notify_read(ctx, app_ctx); return; co_error: perror("Failed to TCP write"); exit(EXIT_FAILURE); } void on_udp_read(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) { struct buffer_packet* bp; struct evt_core_fdinfo *to_fdinfo; struct naive_ctx* app_ctx = fdinfo->cat->app_ctx; int read_res = FDS_READY; char url[255]; // 1. Get current read buffer OR a new read buffer OR subscribe to be notified later if ((bp = get_read_buffer(app_ctx, fdinfo)) == NULL) return; // 2. Read packet from socket bp->ip.ap.str.port = url_get_port_int (fdinfo->url); read_res = read_packet_from_udp (fdinfo->fd, bp, fdinfo->other); if (read_res == FDS_ERR) goto co_error; if (bp->mode != BP_WRITING) return; // 3. A whole packet has been read, we will find someone to write it sprintf(url, "tcp:write:127.0.0.1:7500"); to_fdinfo = evt_core_get_from_url (ctx, url); if (to_fdinfo == NULL) { fprintf(stderr, "No fd for URL %s in udp-read. Dropping packet :( \n", url); mv_buffer_wtor (app_ctx, fdinfo, bp); return; } printf("Pass packet from %s to %s\n", fdinfo->url, url); // 4. We move the buffer and notify the target mv_buffer_rtow (app_ctx, fdinfo, to_fdinfo, bp); on_tcp_write(ctx, to_fdinfo); return; co_error: perror("Failed to UDP read"); exit(EXIT_FAILURE); } void on_udp_write (struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) { struct buffer_packet* bp; struct naive_ctx* app_ctx = fdinfo->cat->app_ctx; int write_res = FDS_READY; // 1. Get current write buffer OR a buffer from the waiting queue OR leave if ((bp = get_write_buffer(app_ctx, fdinfo)) == NULL) return; // 2. Write buffer write_res = write_packet_to_udp(fdinfo->fd, bp, fdinfo->other); if (write_res == FDS_ERR) goto co_error; if (bp->mode != BP_READING) return; // 3. A whole packet has been written // Release the buffer and notify mv_buffer_wtor(app_ctx, fdinfo, bp); notify_read(ctx, app_ctx); return; co_error: perror("Failed to UDP write"); exit(EXIT_FAILURE); } void naive_free_simple(void* v) { free(v); } void on_err(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) { struct naive_ctx* app_ctx = fdinfo->cat->app_ctx; struct buffer_packet* bp; // 1. If has a "used" buffer, remove it bp = g_hash_table_lookup (app_ctx->used_buffer, &(fdinfo->fd)); if (bp != NULL) { g_hash_table_remove (app_ctx->used_buffer, &(fdinfo->fd)); memset(bp, 0, sizeof(struct buffer_packet)); g_queue_push_tail(app_ctx->free_buffer, bp); } // 2. If appears in the write waiting queue, remove it GQueue* writew = g_hash_table_lookup (app_ctx->write_waiting, &(fdinfo->fd)); while (writew != NULL && (bp = g_queue_pop_head (writew)) != NULL) { memset(bp, 0, sizeof(struct buffer_packet)); g_queue_push_tail(app_ctx->free_buffer, bp); } g_hash_table_remove (app_ctx->write_waiting, &(fdinfo->fd)); // 3. If appears in the read waiting queue, remove it g_queue_remove_all (app_ctx->read_waiting, &(fdinfo->fd)); } void algo_naive(struct algo_skel* as) { struct naive_ctx* ctx = malloc(sizeof(struct naive_ctx)); if (ctx == NULL) goto init_err; memset(ctx, 0, sizeof(struct naive_ctx)); ctx->free_buffer = g_queue_new (); ctx->read_waiting = g_queue_new (); ctx->used_buffer = g_hash_table_new(g_int_hash, g_int_equal); ctx->write_waiting = g_hash_table_new_full (g_int_hash, g_int_equal, NULL, naive_free_simple); for (int i = 0; i < sizeof(ctx->bps) / sizeof(ctx->bps[0]); i++) { g_queue_push_tail(ctx->free_buffer, &(ctx->bps[i])); } as->on_tcp_co.name = "tcp-listen"; as->on_tcp_co.flags = EPOLLIN; as->on_tcp_co.free_app_ctx = free_nothing; as->on_tcp_co.cb = on_tcp_co; as->on_tcp_read.name = "tcp-read"; as->on_tcp_read.flags = EPOLLIN | EPOLLET | EPOLLRDHUP; as->on_tcp_read.app_ctx = ctx; as->on_tcp_read.free_app_ctx = free_naive; as->on_tcp_read.cb = on_tcp_read; as->on_tcp_read.err_cb = on_err; ctx->ref_count++; as->on_udp_read.name = "udp-read"; as->on_udp_read.flags = EPOLLIN | EPOLLET; as->on_udp_read.app_ctx = ctx; as->on_udp_read.free_app_ctx = free_naive; as->on_udp_read.cb = on_udp_read; as->on_udp_read.err_cb = on_err; ctx->ref_count++; as->on_tcp_write.name = "tcp-write"; as->on_tcp_write.flags = EPOLLOUT | EPOLLET | EPOLLRDHUP; as->on_tcp_write.app_ctx = ctx; as->on_tcp_write.free_app_ctx = free_naive; as->on_tcp_write.cb = on_tcp_write; as->on_tcp_write.err_cb = on_err; ctx->ref_count++; as->on_udp_write.name = "udp-write"; as->on_udp_write.flags = EPOLLOUT | EPOLLET; as->on_udp_write.app_ctx = ctx; as->on_udp_write.free_app_ctx = free_naive; as->on_udp_write.cb = on_udp_write; as->on_udp_write.err_cb = on_err; ctx->ref_count++; return; init_err: fprintf(stderr, "Failed to init algo naive\n"); exit(EXIT_FAILURE); }