1 files changed, 321 insertions, 0 deletions

diff --git a/sway/ipc.c b/sway/ipc.c
new file mode 100644
index 00000000..39e580cd
--- /dev/null
+++ b/sway/ipc.c
@@ -0,0 +1,321 @@
+// See https://i3wm.org/docs/ipc.html for protocol information
+
+#include <errno.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <stdbool.h>
+#include <wlc/wlc.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stropts.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#include <ctype.h>
+#include "ipc.h"
+#include "log.h"
+#include "config.h"
+#include "commands.h"
+#include "list.h"
+#include "stringop.h"
+
+static int ipc_socket = -1;
+static struct wlc_event_source *ipc_event_source =  NULL;
+static struct sockaddr_un ipc_sockaddr = {
+        .sun_family = AF_UNIX,
+        .sun_path = "/tmp/sway-ipc.sock"
+};
+
+static const char ipc_magic[] = {'i', '3', '-', 'i', 'p', 'c'};
+
+struct ipc_client {
+        struct wlc_event_source *event_source;
+        int fd;
+        uint32_t payload_length;
+        enum ipc_command_type current_command;
+};
+
+int ipc_handle_connection(int fd, uint32_t mask, void *data);
+int ipc_client_handle_readable(int client_fd, uint32_t mask, void *data);
+void ipc_client_disconnect(struct ipc_client *client);
+void ipc_client_handle_command(struct ipc_client *client);
+bool ipc_send_reply(struct ipc_client *client, const char *payload, uint32_t payload_length);
+void ipc_get_workspaces_callback(swayc_t *container, void *data);
+void ipc_get_outputs_callback(swayc_t *container, void *data);
+
+char *json_list(list_t *items);
+
+void ipc_init(void) {
+        ipc_socket = socket(AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK | SOCK_CLOEXEC, 0);
+        if (ipc_socket == -1) {
+                sway_abort("Unable to create IPC socket");
+        }
+
+        if (getenv("SWAYSOCK") != NULL) {
+                strncpy(ipc_sockaddr.sun_path, getenv("SWAYSOCK"), sizeof(ipc_sockaddr.sun_path));
+        }
+
+        unlink(ipc_sockaddr.sun_path);
+        if (bind(ipc_socket, (struct sockaddr *)&ipc_sockaddr, sizeof(ipc_sockaddr)) == -1) {
+                sway_abort("Unable to bind IPC socket");
+        }
+
+        if (listen(ipc_socket, 3) == -1) {
+                sway_abort("Unable to listen on IPC socket");
+        }
+
+        // Set i3 IPC socket path so that i3-msg works out of the box
+        setenv("I3SOCK", ipc_sockaddr.sun_path, 1);
+
+        ipc_event_source = wlc_event_loop_add_fd(ipc_socket, WLC_EVENT_READABLE, ipc_handle_connection, NULL);
+}
+
+void ipc_terminate(void) {
+        if (ipc_event_source) {
+                wlc_event_source_remove(ipc_event_source);
+        }
+        close(ipc_socket);
+        unlink(ipc_sockaddr.sun_path);
+}
+
+int ipc_handle_connection(int fd, uint32_t mask, void *data) {
+        (void) fd; (void) data;
+        sway_log(L_DEBUG, "Event on IPC listening socket");
+        assert(mask == WLC_EVENT_READABLE);
+
+        int client_fd = accept(ipc_socket, NULL, NULL);
+        if (client_fd == -1) {
+                sway_log_errno(L_INFO, "Unable to accept IPC client connection");
+                return 0;
+        }
+
+        int flags;
+        if ((flags=fcntl(client_fd, F_GETFD)) == -1 || fcntl(client_fd, F_SETFD, flags|FD_CLOEXEC) == -1) {
+                sway_log_errno(L_INFO, "Unable to set CLOEXEC on IPC client socket");
+                return 0;
+        }
+
+        struct ipc_client* client = malloc(sizeof(struct ipc_client));
+        client->payload_length = 0;
+        client->fd = client_fd;
+        client->event_source = wlc_event_loop_add_fd(client_fd, WLC_EVENT_READABLE, ipc_client_handle_readable, client);
+
+        return 0;
+}
+
+static const int ipc_header_size = sizeof(ipc_magic)+8;
+
+int ipc_client_handle_readable(int client_fd, uint32_t mask, void *data) {
+        struct ipc_client *client = data;
+        sway_log(L_DEBUG, "Event on IPC client socket %d", client_fd);
+
+        if (mask & WLC_EVENT_ERROR) {
+                sway_log(L_INFO, "IPC Client socket error, removing client");
+                ipc_client_disconnect(client);
+                return 0;
+        }
+
+        if (mask & WLC_EVENT_HANGUP) {
+                ipc_client_disconnect(client);
+                return 0;
+        }
+
+        int read_available;
+        ioctl(client_fd, FIONREAD, &read_available);
+
+        // Wait for the rest of the command payload in case the header has already been read
+        if (client->payload_length > 0) {
+                if (read_available >= client->payload_length) {
+                        ipc_client_handle_command(client);
+                }
+                else {
+                        sway_log(L_DEBUG, "Too little data to read payload on IPC Client socket, waiting for more (%d < %d)", read_available, client->payload_length);
+                }
+                return 0;
+        }
+
+        if (read_available < ipc_header_size) {
+                sway_log(L_DEBUG, "Too little data to read header on IPC Client socket, waiting for more (%d < %d)", read_available, ipc_header_size);
+                return 0;
+        }
+
+        char buf[ipc_header_size];
+        ssize_t received = recv(client_fd, buf, ipc_header_size, 0);
+        if (received == -1) {
+                sway_log_errno(L_INFO, "Unable to receive header from IPC client");
+                ipc_client_disconnect(client);
+                return 0;
+        }
+
+        if (memcmp(buf, ipc_magic, sizeof(ipc_magic)) != 0) {
+                sway_log(L_DEBUG, "IPC header check failed");
+                ipc_client_disconnect(client);
+                return 0;
+        }
+
+        client->payload_length = *(uint32_t *)&buf[sizeof(ipc_magic)];
+        client->current_command = (enum ipc_command_type) *(uint32_t *)&buf[sizeof(ipc_magic)+4];
+
+        if (read_available - received >= client->payload_length) {
+                ipc_client_handle_command(client);
+        }
+
+        return 0;
+}
+
+void ipc_client_disconnect(struct ipc_client *client)
+{
+        if (!sway_assert(client != NULL, "client != NULL")) {
+                return;
+        }
+
+        sway_log(L_INFO, "IPC Client %d disconnected", client->fd);
+        wlc_event_source_remove(client->event_source);
+        close(client->fd);
+        free(client);
+}
+
+void ipc_client_handle_command(struct ipc_client *client) {
+        if (!sway_assert(client != NULL, "client != NULL")) {
+                return;
+        }
+
+        char buf[client->payload_length + 1];
+        if (client->payload_length > 0)
+        {
+                ssize_t received = recv(client->fd, buf, client->payload_length, 0);
+                if (received == -1)
+                {
+                        sway_log_errno(L_INFO, "Unable to receive payload from IPC client");
+                        ipc_client_disconnect(client);
+                        return;
+                }
+        }
+
+        switch (client->current_command) {
+        case IPC_COMMAND:
+        {
+                buf[client->payload_length] = '\0';
+                bool success = handle_command(config, buf);
+                char reply[64];
+                int length = snprintf(reply, sizeof(reply), "{\"success\":%s}", success ? "true" : "false");
+                ipc_send_reply(client, reply, (uint32_t) length);
+                break;
+        }
+        case IPC_GET_WORKSPACES:
+        {
+                list_t *workspaces = create_list();
+                container_map(&root_container, ipc_get_workspaces_callback, workspaces);
+                char *json = json_list(workspaces);
+                free_flat_list(workspaces);
+                ipc_send_reply(client, json, strlen(json));
+                free(json);
+                break;
+        }
+        case IPC_GET_OUTPUTS:
+        {
+                list_t *outputs = create_list();
+                container_map(&root_container, ipc_get_outputs_callback, outputs);
+                char *json = json_list(outputs);
+                free_flat_list(outputs);
+                ipc_send_reply(client, json, strlen(json));
+                free(json);
+                break;
+        }
+        default:
+                sway_log(L_INFO, "Unknown IPC command type %i", client->current_command);
+                ipc_client_disconnect(client);
+                break;
+        }
+
+        client->payload_length = 0;
+}
+
+bool ipc_send_reply(struct ipc_client *client, const char *payload, uint32_t payload_length) {
+        assert(payload);
+
+        char data[ipc_header_size];
+
+        memcpy(data, ipc_magic, sizeof(ipc_magic));
+        *(uint32_t *)&(data[sizeof(ipc_magic)]) = payload_length;
+        *(uint32_t *)&(data[sizeof(ipc_magic)+4]) = client->current_command;
+
+        if (write(client->fd, data, ipc_header_size) == -1) {
+                sway_log_errno(L_INFO, "Unable to send header to IPC client");
+                ipc_client_disconnect(client);
+                return false;
+        }
+
+        if (write(client->fd, payload, payload_length) == -1) {
+                sway_log_errno(L_INFO, "Unable to send payload to IPC client");
+                ipc_client_disconnect(client);
+                return false;
+        }
+
+        return true;
+}
+
+char *json_list(list_t *items) {
+        char *json_elements = join_list(items, ",");
+        size_t len = strlen(json_elements);
+        char *json = malloc(len + 3);
+        json[0] = '[';
+        memcpy(json + 1, json_elements, len);
+        json[len+1] = ']';
+        json[len+2] = '\0';
+        free(json_elements);
+        return json;
+}
+
+void ipc_get_workspaces_callback(swayc_t *container, void *data) {
+        if (container->type == C_WORKSPACE) {
+                char *json = malloc(512); // Output should usually be around 180 chars
+                int num = isdigit(container->name[0]) ? atoi(container->name) : -1;
+                // TODO: escape the name (quotation marks, unicode)
+                sprintf(json,
+                        "{"
+                                "\"num\":%d,"
+                                "\"name\":\"%s\","
+                                "\"visible\":%s,"
+                                "\"focused\":%s,"
+                                "\"rect\":{"
+                                        "\"x\":%d,"
+                                        "\"y\":%d,"
+                                        "\"width\":%d,"
+                                        "\"height\":%d"
+                                "},"
+                                "\"output\":\"%s\","
+                                "\"urgent\":%s"
+                        "}",
+                        num, container->name, container->visible ? "true" : "false", container->is_focused ? "true" : "false",
+                        container->x, container->y, container->width, container->height,
+                        container->parent->name, "false" // TODO: urgent hint
+                );
+                list_add((list_t *)data, json);
+        }
+}
+
+void ipc_get_outputs_callback(swayc_t *container, void *data) {
+        if (container->type == C_OUTPUT) {
+                char *json = malloc(512); // Output should usually be around 130 chars
+                // TODO: escape the name (quotation marks, unicode)
+                sprintf(json,
+                        "{"
+                                "\"name\":\"%s\","
+                                "\"active\":%s,"
+                                "\"primary\":%s,"
+                                "\"rect\":{"
+                                        "\"x\":%d,"
+                                        "\"y\":%d,"
+                                        "\"width\":%d,"
+                                        "\"height\":%d"
+                                "},"
+                                "\"current_workspace\":\"%s\""
+                        "}",
+                        container->name, "true", "false", // TODO: active, primary
+                        container->x, container->y, container->width, container->height,
+                        container->focused ? container->focused->name : ""
+                );
+                list_add((list_t *)data, json);
+        }
+}