Progress
This commit is contained in:
+325
-235
@@ -20,6 +20,10 @@
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#define TAG_RETRIEVE_METADATA_FOR_READ 1
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#define TAG_RETRIEVE_METADATA_FOR_WRITE 2
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#define TAG_COMMIT_WRITE 3
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#define TAG_UPLOAD_CHUNK_MIN 1000
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#define TAG_UPLOAD_CHUNK_MAX 2000
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typedef struct {
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SHA256 hash;
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@@ -127,9 +131,21 @@ typedef struct {
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} MetadataServer;
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typedef struct {
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bool used;
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Address addr;
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bool used;
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// List of addresses associated to this chunk server
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int num_addrs;
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Address addrs[MAX_CHUNK_SERVER_ADDR];
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// Index of the address currently in use
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int current_addr_idx;
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// If the connection was established
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bool connected;
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RequestQueue reqs;
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} ChunkServer;
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struct TinyDFS {
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@@ -248,39 +264,71 @@ request_queue_pop(RequestQueue *reqs, Request *req)
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return 0;
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}
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static bool
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have_insertection(Address *a, int a_num, Address *b, int b_num)
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{
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for (int i = 0; i < a_num; i++)
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for (int j = 0; j < b_num; j++)
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if (addr_eql(a[i], b[j]))
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return true;
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return false;
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}
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// Get or create connection to a chunk server
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static int get_chunk_server_connection(TinyDFS *tdfs, Address addr)
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static ByteQueue *get_chunk_server_output_buffer(TinyDFS *tdfs, Address *addrs, int num_addrs)
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{
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// Check if already connected
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for (int i = 0; i < tdfs->num_chunk_servers; i++) {
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if (tdfs->chunk_servers[i].used && addr_eql(tdfs->chunk_servers[i].addr, addr)) {
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int conn_idx = tcp_index_from_tag(&tdfs->tcp, i);
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if (conn_idx >= 0)
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return i;
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}
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}
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// Find free slot
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int idx = -1;
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for (int i = 0; i < MAX_CHUNK_SERVERS; i++) {
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if (!tdfs->chunk_servers[i].used) {
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idx = i;
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int found = -1;
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for (int i = 0; i < tdfs->num_chunk_servers; i++) {
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if (!tdfs->chunk_servers[i].used)
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continue;
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if (have_insertection(addrs, num_addrs, tdfs->chunk_servers[i].addrs, tdfs->chunk_servers[i].num_addrs)) {
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found = i;
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break;
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}
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}
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if (idx < 0) return -1;
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// Connect
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if (tcp_connect(&tdfs->tcp, addr, idx, NULL) < 0)
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return -1;
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ByteQueue *output;
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if (found == -1) {
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// Initialize
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tdfs->chunk_servers[idx].used = true;
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tdfs->chunk_servers[idx].addr = addr;
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request_queue_init(&tdfs->chunk_servers[idx].reqs);
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tdfs->num_chunk_servers++;
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if (tdfs->num_chunk_servers == MAX_CHUNK_SERVERS)
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return NULL;
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return idx;
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// Find free slot
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found = 0;
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while (tdfs->chunk_servers[found].used)
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found++;
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if (num_addrs > MAX_CHUNK_SERVER_ADDR)
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num_addrs = MAX_CHUNK_SERVER_ADDR;
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tdfs->chunk_servers[found].num_addrs = num_addrs;
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memcpy(tdfs->chunk_servers[found].addrs, addrs, num_addrs * sizeof(Address));
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tdfs->chunk_servers[found].used = true;
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tdfs->chunk_servers[found].current_addr_idx = 0;
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tdfs->chunk_servers[found].connected = false;
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request_queue_init(&tdfs->chunk_servers[found].reqs);
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if (tcp_connect(&tdfs->tcp, addr, found, &output) < 0)
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return NULL;
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// Initialize
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tdfs->chunk_servers[idx].used = true;
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tdfs->chunk_servers[idx].addr = addr;
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request_queue_init(&tdfs->chunk_servers[idx].reqs);
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tdfs->num_chunk_servers++;
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} else {
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int conn_idx = tcp_index_from_tag(&tdfs->tcp, found);
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assert(conn_idx > -1);
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output = tcp_output_buffer(&tdfs->tcp, conn_idx);
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}
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return output;
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}
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// Send download request for a chunk
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@@ -973,14 +1021,10 @@ static int start_upload(Operation *o)
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if (found < 0)
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return -1; // No upload can be started at this time
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int ret = get_chunk_server_connection(tdfs, o->uploads[found].address);
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int tag = xxx;
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ByteQueue *output;
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int ret = tcp_connect(tcp, o->uploads[found].address, tag, &output);
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if (ret < 0)
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return -1;
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ByteQueue *output = get_chunk_server_output_buffer(tdfs, &o->uploads[found].address, 1);
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if (output == NULL) {
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// TODO
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}
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if (o->uploads[found].no_hash) {
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@@ -1019,6 +1063,8 @@ static int start_upload(Operation *o)
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}
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}
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// TODO: push request tag to chunk server request queue
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o->uploads[found].status = UPLOAD_PENDING;
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return 0;
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}
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@@ -1031,160 +1077,78 @@ static void process_event_for_write(TinyDFS *tdfs,
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return;
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}
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switch (request_tag) {
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if (request_tag == TAG_RETRIEVE_METADATA_FOR_WRITE) {
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case TAG_RETRIEVE_METADATA_FOR_WRITE:
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{
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// We are expecting one of:
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// MESSAGE_TYPE_READ_ERROR
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// MESSAGE_TYPE_READ_SUCCESS
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// We are expecting one of:
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// MESSAGE_TYPE_READ_ERROR
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// MESSAGE_TYPE_READ_SUCCESS
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BinaryReader reader = { msg.ptr, msg.len, 0 };
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BinaryReader reader = { msg.ptr, msg.len, 0 };
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if (!binary_read(&reader, NULL, sizeof(uint16_t))) {
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if (!binary_read(&reader, NULL, sizeof(uint16_t))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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uint16_t type;
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if (!binary_read(&reader, &type, sizeof(type))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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if (type != MESSAGE_TYPE_READ_SUCCESS) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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if (!binary_read(&reader, NULL, sizeof(uint32_t))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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uint32_t chunk_size;
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if (!binary_read(&reader, &chunk_size, sizeof(chunk_size))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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uint32_t num_hashes;
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if (!binary_read(&reader, &num_hashes, sizeof(num_hashes))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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// TODO: !!! IMPORTANT !!! This should also account for new chunks, not patched. It does not do so at the moment
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// TODO: This may overestimate by a lot the actual memory required by the array
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client->operations[opidx].uploads = sys_malloc(num_hashes * MAX_CHUNK_HOLDERS * MAX_CHUNK_SERVER_ADDR * sizeof(UploadSchedule));
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if (client->operations[opidx].uploads == NULL) {
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// TODO
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}
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int next_server_lid = 0;
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client->operations[opidx].num_uploads = 0;
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for (uint32_t i = 0; i < num_hashes; i++) {
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void *src = xxx;
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int off = xxx;
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int len = xxx;
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SHA256 hash;
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if (!binary_read(&reader, &hash, sizeof(hash))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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uint16_t type;
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if (!binary_read(&reader, &type, sizeof(type))) {
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uint32_t num_holders;
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if (!binary_read(&reader, &num_holders, sizeof(num_holders))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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if (type != MESSAGE_TYPE_READ_SUCCESS) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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for (uint32_t j = 0; j < num_holders; j++) {
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if (!binary_read(&reader, NULL, sizeof(uint32_t))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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uint32_t chunk_size;
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if (!binary_read(&reader, &chunk_size, sizeof(chunk_size))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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uint32_t num_hashes;
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if (!binary_read(&reader, &num_hashes, sizeof(num_hashes))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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// TODO: !!! IMPORTANT !!! This should also account for new chunks, not patched. It does not do so at the moment
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// TODO: This may overestimate by a lot the actual memory required by the array
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client->operations[opidx].uploads = sys_malloc(num_hashes * MAX_CHUNK_HOLDERS * MAX_CHUNK_SERVER_ADDR * sizeof(UploadSchedule));
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if (client->operations[opidx].uploads == NULL) {
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// TODO
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}
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int next_server_lid = 0;
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client->operations[opidx].num_uploads = 0;
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for (uint32_t i = 0; i < num_hashes; i++) {
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void *src = xxx;
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int off = xxx;
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int len = xxx;
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SHA256 hash;
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if (!binary_read(&reader, &hash, sizeof(hash))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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uint32_t num_holders;
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if (!binary_read(&reader, &num_holders, sizeof(num_holders))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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for (uint32_t j = 0; j < num_holders; j++) {
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int server_lid = next_server_lid;
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next_server_lid++;
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uint32_t num_ipv4;
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if (!binary_read(&reader, &num_ipv4, sizeof(num_ipv4))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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for (uint32_t k = 0; k < num_ipv4; k++) {
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IPv4 ipv4;
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if (!binary_read(&reader, &ipv4, sizeof(ipv4))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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uint16_t port;
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if (!binary_read(&reader, &port, sizeof(port))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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UploadSchedule upload;
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upload.status = UPLOAD_WAITING;
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upload.server_lid = server_lid;
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upload.no_hash = false;
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upload.address.is_ipv4 = true;
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upload.address.ipv4 = ipv4;
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upload.address.port = port;
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upload.hash = hash;
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upload.src = src;
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upload.off = off;
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upload.len = len;
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int n = client->operations[opidx].num_uploads++;
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client->operations[opidx].uploads[n] = upload;
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}
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uint32_t num_ipv6;
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if (!binary_read(&reader, &num_ipv6, sizeof(num_ipv6))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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for (uint32_t k = 0; k < num_ipv6; k++) {
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IPv6 ipv6;
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if (!binary_read(&reader, &ipv6, sizeof(ipv6))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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uint16_t port;
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if (!binary_read(&reader, &port, sizeof(port))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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UploadSchedule upload;
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upload.status = UPLOAD_WAITING;
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upload.server_lid = server_lid;
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upload.no_hash = false;
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upload.address.is_ipv4 = false;
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upload.address.ipv6 = ipv6;
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upload.address.port = port;
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upload.hash = hash;
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upload.src = src;
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upload.off = off;
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upload.len = len;
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int n = client->operations[opidx].num_uploads++;
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client->operations[opidx].uploads[n] = upload;
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}
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}
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}
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uint32_t num_locations;
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if (!binary_read(&reader, &num_locations, sizeof(num_locations))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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for (uint32_t i = 0; i < num_locations; i++) {
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int server_lid = next_server_lid;
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next_server_lid++;
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uint32_t num_ipv4;
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if (!binary_read(&reader, &num_ipv4, sizeof(num_ipv4))) {
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@@ -1206,7 +1170,19 @@ static void process_event_for_write(TinyDFS *tdfs,
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return;
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}
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// TODO
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UploadSchedule upload;
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upload.status = UPLOAD_WAITING;
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upload.server_lid = server_lid;
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upload.no_hash = false;
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upload.address.is_ipv4 = true;
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upload.address.ipv4 = ipv4;
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upload.address.port = port;
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upload.hash = hash;
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upload.src = src;
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upload.off = off;
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upload.len = len;
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int n = client->operations[opidx].num_uploads++;
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client->operations[opidx].uploads[n] = upload;
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}
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uint32_t num_ipv6;
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@@ -1229,74 +1205,144 @@ static void process_event_for_write(TinyDFS *tdfs,
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return;
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}
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// TODO
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UploadSchedule upload;
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upload.status = UPLOAD_WAITING;
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upload.server_lid = server_lid;
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upload.no_hash = false;
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upload.address.is_ipv4 = false;
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upload.address.ipv6 = ipv6;
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upload.address.port = port;
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upload.hash = hash;
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upload.src = src;
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upload.off = off;
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upload.len = len;
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int n = client->operations[opidx].num_uploads++;
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client->operations[opidx].uploads[n] = upload;
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}
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}
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}
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// Now start the first batch of uploads
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int started = 0;
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for (int i = 0; i < xxx; i++) {
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if (start_upload(&tdfs->operations[opidx]) == 0)
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started++;
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}
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uint32_t num_locations;
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if (!binary_read(&reader, &num_locations, sizeof(num_locations))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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if (started == 0) {
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// We already failed
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for (uint32_t i = 0; i < num_locations; i++) {
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uint32_t num_ipv4;
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if (!binary_read(&reader, &num_ipv4, sizeof(num_ipv4))) {
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tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
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return;
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}
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// TODO: Now we need to upload the patches to N of the
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// chunk servers that are holding each old chunk
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// All new chunks need to be written to the specified
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// locations at least N times. If any upload fails,
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// the write fails. If all writes succede, the client
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// sends the metadata server a WRITE operation
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// swapping the old hashes with the new ones.
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//
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// The algorithm should go like this:
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// - Iterate over each chunk
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// - Pick the first N holders of the chunk. If less than N
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// are available, pick M.
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// - For each pick, take the first address and start the
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// chunk upload
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//
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// If an upload fails,
|
||||
//
|
||||
//
|
||||
//
|
||||
// example upload schedule:
|
||||
// chunk_A server_A addr_0
|
||||
// chunk_A server_A addr_1
|
||||
// chunk_A server_B addr_0
|
||||
// chunk_A server_B addr_1
|
||||
// chunk_A server_B addr_2
|
||||
// chunk_A server_C addr_0
|
||||
// chunk_B server_D addr_0
|
||||
// chunk_B server_E addr_0
|
||||
// chunk_B server_E addr_1
|
||||
// chunk_B server_F addr_0
|
||||
//
|
||||
// If an upload succedes, all uploads of the chunk to the same server
|
||||
// are removed and if this was the N-th successful upload of a chunk,
|
||||
// all uploads of the same chunk are removed.
|
||||
//
|
||||
// Uploads to the same chunk server with different addresses can't
|
||||
// be parallelized, so
|
||||
for (uint32_t k = 0; k < num_ipv4; k++) {
|
||||
|
||||
// The client should not try any random N chunk servers
|
||||
// for upload. It must try all chunk servers until N respond
|
||||
IPv4 ipv4;
|
||||
if (!binary_read(&reader, &ipv4, sizeof(ipv4))) {
|
||||
tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
|
||||
return;
|
||||
}
|
||||
|
||||
tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
|
||||
uint16_t port;
|
||||
if (!binary_read(&reader, &port, sizeof(port))) {
|
||||
tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
|
||||
return;
|
||||
}
|
||||
|
||||
// TODO
|
||||
}
|
||||
|
||||
uint32_t num_ipv6;
|
||||
if (!binary_read(&reader, &num_ipv6, sizeof(num_ipv6))) {
|
||||
tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
|
||||
return;
|
||||
}
|
||||
|
||||
for (uint32_t k = 0; k < num_ipv6; k++) {
|
||||
|
||||
IPv6 ipv6;
|
||||
if (!binary_read(&reader, &ipv6, sizeof(ipv6))) {
|
||||
tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
|
||||
return;
|
||||
}
|
||||
|
||||
uint16_t port;
|
||||
if (!binary_read(&reader, &port, sizeof(port))) {
|
||||
tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
|
||||
return;
|
||||
}
|
||||
|
||||
// TODO
|
||||
}
|
||||
}
|
||||
return;
|
||||
|
||||
default:
|
||||
break;
|
||||
// Now start the first batch of uploads
|
||||
int started = 0;
|
||||
for (int i = 0; i < xxx; i++) {
|
||||
if (start_upload(&tdfs->operations[opidx]) == 0)
|
||||
started++;
|
||||
}
|
||||
|
||||
if (started == 0) {
|
||||
// We already failed
|
||||
tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
|
||||
return;
|
||||
}
|
||||
|
||||
// TODO: Now we need to upload the patches to N of the
|
||||
// chunk servers that are holding each old chunk
|
||||
// All new chunks need to be written to the specified
|
||||
// locations at least N times. If any upload fails,
|
||||
// the write fails. If all writes succede, the client
|
||||
// sends the metadata server a WRITE operation
|
||||
// swapping the old hashes with the new ones.
|
||||
//
|
||||
// The algorithm should go like this:
|
||||
// - Iterate over each chunk
|
||||
// - Pick the first N holders of the chunk. If less than N
|
||||
// are available, pick M.
|
||||
// - For each pick, take the first address and start the
|
||||
// chunk upload
|
||||
//
|
||||
// If an upload fails,
|
||||
//
|
||||
//
|
||||
//
|
||||
// example upload schedule:
|
||||
// chunk_A server_A addr_0
|
||||
// chunk_A server_A addr_1
|
||||
// chunk_A server_B addr_0
|
||||
// chunk_A server_B addr_1
|
||||
// chunk_A server_B addr_2
|
||||
// chunk_A server_C addr_0
|
||||
// chunk_B server_D addr_0
|
||||
// chunk_B server_E addr_0
|
||||
// chunk_B server_E addr_1
|
||||
// chunk_B server_F addr_0
|
||||
//
|
||||
// If an upload succedes, all uploads of the chunk to the same server
|
||||
// are removed and if this was the N-th successful upload of a chunk,
|
||||
// all uploads of the same chunk are removed.
|
||||
//
|
||||
// Uploads to the same chunk server with different addresses can't
|
||||
// be parallelized, so
|
||||
|
||||
// The client should not try any random N chunk servers
|
||||
// for upload. It must try all chunk servers until N respond
|
||||
|
||||
} else if (request_tag >= TAG_UPLOAD_CHUNK_MIN && request_tag <= TAG_UPLOAD_CHUNK_MAX) {
|
||||
|
||||
// TODO
|
||||
|
||||
} else {
|
||||
|
||||
assert(request_tag == TAG_COMMIT_WRITE);
|
||||
|
||||
// TODO
|
||||
|
||||
tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
|
||||
}
|
||||
|
||||
// Write operation processing not fully implemented
|
||||
tdfs->operations[opidx].result = (TinyDFS_Result) { .type=TINYDFS_RESULT_WRITE_ERROR };
|
||||
}
|
||||
|
||||
static void process_event(TinyDFS *tdfs,
|
||||
@@ -1354,22 +1400,66 @@ int tinydfs_process_events(TinyDFS *tdfs, void **contexts, struct pollfd *polled
|
||||
switch (events[i].type) {
|
||||
|
||||
case EVENT_CONNECT:
|
||||
{
|
||||
int tag = tcp_get_tag(&tdfs->tcp, conn_idx);
|
||||
if (tag != TAG_METADATA_SERVER)
|
||||
tdfs->chunk_servers[tag].connected = true;
|
||||
}
|
||||
break;
|
||||
|
||||
case EVENT_DISCONNECT:
|
||||
{
|
||||
RequestQueue *reqs;
|
||||
// A TCP connection was just dropped.
|
||||
// For clients, connections can be:
|
||||
// 1. To the metadata server
|
||||
// 2. or to a chunk server
|
||||
// If requests were buffered for the metadata
|
||||
// or chunk server, they are considered as failed
|
||||
// and their failure event is processed.
|
||||
//
|
||||
// If a chunk server was never connected,
|
||||
// then it's possible that using a different
|
||||
// address will allow connecting succesfully
|
||||
// and send the buffered messages. Therefore,
|
||||
// if a chunk server wasn't connected and
|
||||
// there are addresses to try, the messages
|
||||
// are not dropped and a new connect process
|
||||
// is started.
|
||||
|
||||
RequestQueue *reqs = NULL;
|
||||
|
||||
int tag = tcp_get_tag(&tdfs->tcp, conn_idx);
|
||||
if (tag == TAG_METADATA_SERVER)
|
||||
reqs = &tdfs->metadata_server.reqs;
|
||||
else {
|
||||
assert(tag > -1);
|
||||
reqs = &tdfs->chunk_servers[tag].reqs;
|
||||
|
||||
if (tdfs->chunk_servers[tag].connected)
|
||||
reqs = &tdfs->chunk_servers[tag].reqs;
|
||||
else {
|
||||
|
||||
tdfs->chunk_servers[tag].current_addr_idx++;
|
||||
|
||||
bool started = false;
|
||||
while (tdfs->chunk_servers[tag].current_addr_idx < tdfs->chunk_servers[tag].num_addrs) {
|
||||
|
||||
if (tcp_connect(&tdfs->tcp, tdfs->chunk_servers[tag].addrs[addr_idx], tag, NULL) == 0) {
|
||||
started = true;
|
||||
break;
|
||||
}
|
||||
|
||||
tdfs->chunk_servers[tag].current_addr_idx++;
|
||||
}
|
||||
|
||||
if (started)
|
||||
reqs = &tdfs->chunk_servers[tag].reqs;
|
||||
}
|
||||
}
|
||||
|
||||
for (Request req; request_queue_pop(reqs, &req) == 0; )
|
||||
process_event(tdfs, req.opidx, req.tag, (ByteView) { NULL, 0 });
|
||||
if (reqs) {
|
||||
for (Request req; request_queue_pop(reqs, &req) == 0; )
|
||||
process_event(tdfs, req.opidx, req.tag, (ByteView) { NULL, 0 });
|
||||
}
|
||||
}
|
||||
break;
|
||||
|
||||
|
||||
Reference in New Issue
Block a user