LibGemini: Implement basic Gemini protocol support

Libraries/LibGemini/Job.cpp

@@ -0,0 +1,160 @@
+/*
+ * Copyright (c) 2020, The SerenityOS developers.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <LibGemini/GeminiResponse.h>
+#include <LibGemini/Job.h>
+#include <stdio.h>
+#include <unistd.h>
+
+//#define JOB_DEBUG
+
+namespace Gemini {
+
+Job::Job(const GeminiRequest& request)
+    : m_request(request)
+{
+}
+
+Job::~Job()
+{
+}
+
+void Job::on_socket_connected()
+{
+    register_on_ready_to_write([this] {
+        if (m_sent_data)
+            return;
+        m_sent_data = true;
+        auto raw_request = m_request.to_raw_request();
+#ifdef JOB_DEBUG
+        dbg() << "Job: raw_request:";
+        dbg() << String::copy(raw_request).characters();
+#endif
+        bool success = write(raw_request);
+        if (!success)
+            deferred_invoke([this](auto&) { did_fail(Core::NetworkJob::Error::TransmissionFailed); });
+    });
+    register_on_ready_to_read([this] {
+        if (is_cancelled())
+            return;
+
+        if (m_state == State::InStatus) {
+            if (!can_read_line())
+                return;
+
+            auto line = read_line(PAGE_SIZE);
+            if (line.is_null()) {
+                fprintf(stderr, "Job: Expected status line\n");
+                return deferred_invoke([this](auto&) { did_fail(Core::NetworkJob::Error::TransmissionFailed); });
+            }
+
+            auto parts = String::copy(line, Chomp).split_limit(' ', 2);
+            if (parts.size() != 2) {
+                fprintf(stderr, "Job: Expected 2-part status line, got '%s'\n", line.data());
+                return deferred_invoke([this](auto&) { did_fail(Core::NetworkJob::Error::ProtocolFailed); });
+            }
+
+            bool ok;
+            m_status = parts[0].to_uint(ok);
+            if (!ok) {
+                fprintf(stderr, "Job: Expected numeric status code\n");
+                return deferred_invoke([this](auto&) { did_fail(Core::NetworkJob::Error::ProtocolFailed); });
+            }
+
+            m_meta = parts[1];
+
+            if (m_status >= 10 && m_status < 20) {
+                m_state = State::Finished;
+            } else if (m_status >= 20 && m_status < 30) {
+                m_state = State::InBody;
+            } else if (m_status >= 30 && m_status < 40) {
+                m_state = State::Finished;
+            } else if (m_status >= 40 && m_status < 50) {
+                m_state = State::Finished;
+            } else if (m_status >= 50 && m_status < 60) {
+                m_state = State::Finished;
+            } else if (m_status >= 60 && m_status < 70) {
+                m_state = State::InBody;
+            } else {
+                fprintf(stderr, "Job: Expected status between 10 and 69; instead got %d\n", m_status);
+                return deferred_invoke([this](auto&) { did_fail(Core::NetworkJob::Error::ProtocolFailed); });
+            }
+
+            return;
+        }
+
+        ASSERT(m_state == State::InBody || m_state == State::Finished);
+
+        read_while_data_available([&] {
+            auto read_size = 64 * KB;
+
+            auto payload = receive(read_size);
+            if (!payload) {
+                if (eof()) {
+                    finish_up();
+                    return IterationDecision::Break;
+                }
+
+                if (should_fail_on_empty_payload()) {
+                    deferred_invoke([this](auto&) { did_fail(Core::NetworkJob::Error::ProtocolFailed); });
+                    return IterationDecision::Break;
+                }
+            }
+
+            m_received_buffers.append(payload);
+            m_received_size += payload.size();
+
+            did_progress({}, m_received_size);
+
+            return IterationDecision::Continue;
+        });
+
+        if (!is_established()) {
+#ifdef JOB_DEBUG
+            dbg() << "Connection appears to have closed, finishing up";
+#endif
+            finish_up();
+        }
+    });
+}
+
+void Job::finish_up()
+{
+    m_state = State::Finished;
+    auto flattened_buffer = ByteBuffer::create_uninitialized(m_received_size);
+    u8* flat_ptr = flattened_buffer.data();
+    for (auto& received_buffer : m_received_buffers) {
+        memcpy(flat_ptr, received_buffer.data(), received_buffer.size());
+        flat_ptr += received_buffer.size();
+    }
+    m_received_buffers.clear();
+
+    auto response = GeminiResponse::create(m_status, m_meta, move(flattened_buffer));
+    deferred_invoke([this, response](auto&) {
+        did_finish(move(response));
+    });
+}
+}