Refactored ui-core-control and core-ui-control protocols

Also cleaned the code up from obsolete ui-core-protocol.* and
core-ui-protocol.*

Change-Id: I194bec669d25b68a10c32b2be50bc9da50c52ebb
diff --git a/android/protocol/ui-commands-impl.c b/android/protocol/ui-commands-impl.c
new file mode 100644
index 0000000..456c61e
--- /dev/null
+++ b/android/protocol/ui-commands-impl.c
@@ -0,0 +1,257 @@
+/* Copyright (C) 2010 The Android Open Source Project
+**
+** This software is licensed under the terms of the GNU General Public
+** License version 2, as published by the Free Software Foundation, and
+** may be copied, distributed, and modified under those terms.
+**
+** This program is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+** GNU General Public License for more details.
+*/
+
+/*
+ * Contains the UI-side implementation of the "core-ui-control" service that is
+ * part of the UI control protocol. Here we handle UI control commands received
+ * from the Core.
+ */
+
+#include "console.h"
+//#include "android/hw-control.h"
+#include "android/looper.h"
+#include "android/core-connection.h"
+#include "android/async-utils.h"
+#include "android/sync-utils.h"
+#include "android/utils/system.h"
+#include "android/utils/debug.h"
+#include "android/utils/panic.h"
+#include "android/protocol/ui-commands-impl.h"
+#include "android/protocol/ui-commands-api.h"
+
+/* Enumerates states for the command reader in UICmdImpl instance. */
+typedef enum UICmdImplState {
+    /* The reader is waiting on command header. */
+    EXPECTS_HEADER,
+
+    /* The reader is waiting on command parameters. */
+    EXPECTS_PARAMETERS,
+} UICmdImplState;
+
+/* Descriptor for the UI-side of the "core-ui-control" service. */
+typedef struct UICmdImpl {
+    /* Core connection established for this service. */
+    CoreConnection* core_connection;
+
+    /* Socket descriptor for the UI service. */
+    int             sock;
+
+    /* Command reader state. */
+    UICmdImplState  reader_state;
+
+    /* Incoming command header. */
+    UICmdHeader     cmd_header;
+
+    /* Reader's buffer. This field can point to the cmd_header field of this
+     * structure (when we expect a command header), or to a buffer allocated for
+     * the (when we expect command parameters). */
+    uint8_t*        reader_buffer;
+
+    /* Offset in the reader's buffer where to read next chunk of data. */
+    size_t          reader_offset;
+
+    /* Total number of bytes the reader expects to read. */
+    size_t          reader_bytes;
+} UICmdImpl;
+
+/* Implemented in android/qemulator.c */
+extern void android_emulator_set_window_scale(double scale, int is_dpi);
+
+/* One and only one UICmdImpl instance. */
+static UICmdImpl  _uiCmdImpl;
+
+/* Display brightness change callback. */
+static AndroidHwLightBrightnessCallback _brightness_change_callback = NULL;
+static void* _brightness_change_callback_param = NULL;
+
+/* Destroys UICmdImpl instance. */
+static void
+_uiCmdImpl_destroy()
+{
+    if (_uiCmdImpl.core_connection != NULL) {
+        // Disable I/O callbacks.
+        qemu_set_fd_handler(_uiCmdImpl.sock, NULL, NULL, NULL);
+        core_connection_close(_uiCmdImpl.core_connection);
+        core_connection_free(_uiCmdImpl.core_connection);
+        _uiCmdImpl.core_connection = NULL;
+    }
+    // Properly deallocate the reader buffer.
+    if (_uiCmdImpl.reader_buffer != NULL &&
+        _uiCmdImpl.reader_buffer != (uint8_t*)&_uiCmdImpl.cmd_header) {
+        free(_uiCmdImpl.reader_buffer);
+        _uiCmdImpl.reader_buffer = (uint8_t*)&_uiCmdImpl.cmd_header;
+    }
+}
+
+/* Handles UI control command received from the core.
+ * Param:
+ *  uicmd - UICmdImpl instance that received the command.
+ *  header - UI control command header.
+ *  data - Command parameters formatted accordingly to the command type.
+ */
+static void
+_uiCmdImpl_handle_command(UICmdImpl* uicmd,
+                          const UICmdHeader* header,
+                          const uint8_t* data)
+{
+    switch (header->cmd_type) {
+        case AUICMD_SET_WINDOWS_SCALE:
+        {
+            UICmdSetWindowsScale* cmd = (UICmdSetWindowsScale*)data;
+            android_emulator_set_window_scale(cmd->scale, cmd->is_dpi);
+            break;
+        }
+
+        case AUICMD_CHANGE_DISP_BRIGHTNESS:
+        {
+            UICmdChangeDispBrightness* cmd = (UICmdChangeDispBrightness*)data;
+            if (_brightness_change_callback != NULL) {
+                _brightness_change_callback(_brightness_change_callback_param,
+                                            cmd->light, cmd->brightness);
+            }
+            break;
+        }
+
+        default:
+            derror("Unknown command %d is received from the Core\n",
+                   header->cmd_type);
+            break;
+    }
+}
+
+/* Asynchronous I/O callback reading UI control commands.
+ * Param:
+ *  opaque - UICmdImpl instance.
+ */
+static void
+_uiCmdImpl_io_read(void* opaque)
+{
+    UICmdImpl* uicmd = opaque;
+    int status;
+
+    // Read requests while they are immediately available.
+    for (;;) {
+        // Read next chunk of data.
+        status = read(uicmd->sock, uicmd->reader_buffer + uicmd->reader_offset,
+                      uicmd->reader_bytes - uicmd->reader_offset);
+        if (status == 0) {
+            /* Disconnection, meaning that the core process got termonated. */
+            fprintf(stderr, "core-ui-control service got disconnected\n");
+            _uiCmdImpl_destroy();
+            return;
+        }
+        if (status < 0) {
+            if (errno == EINTR) {
+                /* loop on EINTR */
+                continue;
+            } else if (errno == EWOULDBLOCK || errno == EAGAIN) {
+                // Chunk is not avalable at this point. Come back later.
+                return;
+            }
+        }
+
+        uicmd->reader_offset += status;
+        if (uicmd->reader_offset != uicmd->reader_bytes) {
+            // There are still some data left in the pipe.
+            continue;
+        }
+
+        // All expected data has been read. Time to change the state.
+        if (uicmd->reader_state == EXPECTS_HEADER) {
+            // Header has been read.
+            if (uicmd->cmd_header.cmd_param_size) {
+                // Prepare for the command parameters.
+                uicmd->reader_state = EXPECTS_PARAMETERS;
+                uicmd->reader_offset = 0;
+                uicmd->reader_bytes = uicmd->cmd_header.cmd_param_size;
+                uicmd->reader_buffer = malloc(uicmd->reader_bytes);
+                if (uicmd->reader_buffer == NULL) {
+                    APANIC("Unable to allocate memory for UI command parameters.\n");
+                }
+            } else {
+                // This command doesn't have any parameters. Handle it now.
+                _uiCmdImpl_handle_command(uicmd, &uicmd->cmd_header, NULL);
+                // Prepare for the next command header.
+                uicmd->reader_state = EXPECTS_HEADER;
+                uicmd->reader_offset = 0;
+                uicmd->reader_bytes = sizeof(uicmd->cmd_header);
+                uicmd->reader_buffer = (uint8_t*)&uicmd->cmd_header;
+            }
+        } else {
+            // All command data is in. Handle it.
+            _uiCmdImpl_handle_command(uicmd, &uicmd->cmd_header,
+                                      uicmd->reader_buffer);
+            // Prepare for the next command header.
+            free(uicmd->reader_buffer);
+            uicmd->reader_state = EXPECTS_HEADER;
+            uicmd->reader_offset = 0;
+            uicmd->reader_bytes = sizeof(uicmd->cmd_header);
+            uicmd->reader_buffer = (uint8_t*)&uicmd->cmd_header;
+        }
+    }
+}
+
+int
+uiCmdImpl_create(SockAddress* console_socket)
+{
+    char* handshake = NULL;
+
+    // Setup command reader.
+    _uiCmdImpl.reader_buffer = (uint8_t*)&_uiCmdImpl.cmd_header;
+    _uiCmdImpl.reader_state = EXPECTS_HEADER;
+    _uiCmdImpl.reader_offset = 0;
+    _uiCmdImpl.reader_bytes = sizeof(UICmdHeader);
+
+    // Connect to the core-ui-control service.
+    _uiCmdImpl.core_connection =
+        core_connection_create_and_switch(console_socket, "core-ui-control",
+                                          &handshake);
+    if (_uiCmdImpl.core_connection == NULL) {
+        derror("Unable to connect to the core-ui-control service: %s\n",
+               errno_str);
+        return -1;
+    }
+
+    // Initialze UI command reader.
+    _uiCmdImpl.sock = core_connection_get_socket(_uiCmdImpl.core_connection);
+    if (qemu_set_fd_handler(_uiCmdImpl.sock, _uiCmdImpl_io_read, NULL,
+                            &_uiCmdImpl)) {
+        derror("Unable to set up UI _uiCmdImpl_io_read callback: %s\n",
+               errno_str);
+        _uiCmdImpl_destroy();
+        if (handshake != NULL) {
+            free(handshake);
+        }
+        return -1;
+    }
+
+    fprintf(stdout, "core-ui-control is now connected to the core at %s.",
+            sock_address_to_string(console_socket));
+    if (handshake != NULL) {
+        if (handshake[0] != '\0') {
+            fprintf(stdout, " Handshake: %s", handshake);
+        }
+        free(handshake);
+    }
+    fprintf(stdout, "\n");
+
+    return 0;
+}
+
+int
+uicmd_set_brightness_change_callback(AndroidHwLightBrightnessCallback callback,
+                                     void* opaque)
+{
+    _brightness_change_callback = callback;
+    _brightness_change_callback_param = opaque;
+    return 0;
+}