diff options
Diffstat (limited to 'patch/ipc/ipc.c')
| -rw-r--r-- | patch/ipc/ipc.c | 1202 |
1 files changed, 1202 insertions, 0 deletions
diff --git a/patch/ipc/ipc.c b/patch/ipc/ipc.c new file mode 100644 index 0000000..eae9667 --- /dev/null +++ b/patch/ipc/ipc.c @@ -0,0 +1,1202 @@ +#include "ipc.h" + +#include <errno.h> +#include <fcntl.h> +#include <inttypes.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <sys/epoll.h> +#include <sys/socket.h> +#include <sys/un.h> +#include <unistd.h> +#include <yajl/yajl_gen.h> +#include <yajl/yajl_tree.h> + +#include "util.h" +#include "yajl_dumps.h" + +static struct sockaddr_un sockaddr; +static struct epoll_event sock_epoll_event; +static IPCClientList ipc_clients = NULL; +static int epoll_fd = -1; +static int sock_fd = -1; +static IPCCommand *ipc_commands; +static unsigned int ipc_commands_len; +// Max size is 1 MB +static const uint32_t MAX_MESSAGE_SIZE = 1000000; +static const int IPC_SOCKET_BACKLOG = 5; + +/** + * Create IPC socket at specified path and return file descriptor to socket. + * This initializes the static variable sockaddr. + */ +static int +ipc_create_socket(const char *filename) +{ + char *normal_filename; + char *parent; + const size_t addr_size = sizeof(struct sockaddr_un); + const int sock_type = SOCK_STREAM | SOCK_NONBLOCK | SOCK_CLOEXEC; + + normalizepath(filename, &normal_filename); + + // In case socket file exists + unlink(normal_filename); + + // For portability clear the addr structure, since some implementations have + // nonstandard fields in the structure + memset(&sockaddr, 0, addr_size); + + parentdir(normal_filename, &parent); + // Create parent directories + mkdirp(parent); + free(parent); + + sockaddr.sun_family = AF_LOCAL; + strcpy(sockaddr.sun_path, normal_filename); + free(normal_filename); + + sock_fd = socket(AF_LOCAL, sock_type, 0); + if (sock_fd == -1) { + fputs("Failed to create socket\n", stderr); + return -1; + } + + DEBUG("Created socket at %s\n", sockaddr.sun_path); + + if (bind(sock_fd, (const struct sockaddr *)&sockaddr, addr_size) == -1) { + fputs("Failed to bind socket\n", stderr); + return -1; + } + + DEBUG("Socket binded\n"); + + if (listen(sock_fd, IPC_SOCKET_BACKLOG) < 0) { + fputs("Failed to listen for connections on socket\n", stderr); + return -1; + } + + DEBUG("Now listening for connections on socket\n"); + + return sock_fd; +} + +/** + * Internal function used to receive IPC messages from a given file descriptor. + * + * Returns -1 on error reading (could be EAGAIN or EINTR) + * Returns -2 if EOF before header could be read + * Returns -3 if invalid IPC header + * Returns -4 if message length exceeds MAX_MESSAGE_SIZE + */ +static int +ipc_recv_message(int fd, uint8_t *msg_type, uint32_t *reply_size, + uint8_t **reply) +{ + uint32_t read_bytes = 0; + const int32_t to_read = sizeof(dwm_ipc_header_t); + char header[to_read]; + char *walk = header; + + // Try to read header + while (read_bytes < to_read) { + const ssize_t n = read(fd, header + read_bytes, to_read - read_bytes); + + if (n == 0) { + if (read_bytes == 0) { + fprintf(stderr, "Unexpectedly reached EOF while reading header."); + fprintf(stderr, + "Read %" PRIu32 " bytes, expected %" PRIu32 " total bytes.\n", + read_bytes, to_read); + return -2; + } else { + fprintf(stderr, "Unexpectedly reached EOF while reading header."); + fprintf(stderr, + "Read %" PRIu32 " bytes, expected %" PRIu32 " total bytes.\n", + read_bytes, to_read); + return -3; + } + } else if (n == -1) { + // errno will still be set + return -1; + } + + read_bytes += n; + } + + // Check if magic string in header matches + if (memcmp(walk, IPC_MAGIC, IPC_MAGIC_LEN) != 0) { + fprintf(stderr, "Invalid magic string. Got '%.*s', expected '%s'\n", + IPC_MAGIC_LEN, walk, IPC_MAGIC); + return -3; + } + + walk += IPC_MAGIC_LEN; + + // Extract reply size + memcpy(reply_size, walk, sizeof(uint32_t)); + walk += sizeof(uint32_t); + + if (*reply_size > MAX_MESSAGE_SIZE) { + fprintf(stderr, "Message too long: %" PRIu32 " bytes. ", *reply_size); + fprintf(stderr, "Maximum message size is: %d\n", MAX_MESSAGE_SIZE); + return -4; + } + + // Extract message type + memcpy(msg_type, walk, sizeof(uint8_t)); + walk += sizeof(uint8_t); + + if (*reply_size > 0) + (*reply) = malloc(*reply_size); + else + return 0; + + read_bytes = 0; + while (read_bytes < *reply_size) { + const ssize_t n = read(fd, *reply + read_bytes, *reply_size - read_bytes); + + if (n == 0) { + fprintf(stderr, "Unexpectedly reached EOF while reading payload."); + fprintf(stderr, "Read %" PRIu32 " bytes, expected %" PRIu32 " bytes.\n", + read_bytes, *reply_size); + free(*reply); + return -2; + } else if (n == -1) { + // TODO: Should we return and wait for another epoll event? + // This would require saving the partial read in some way. + if (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK) continue; + + free(*reply); + return -1; + } + + read_bytes += n; + } + + return 0; +} + +/** + * Internal function used to write a buffer to a file descriptor + * + * Returns number of bytes written if successful write + * Returns 0 if no bytes were written due to EAGAIN or EWOULDBLOCK + * Returns -1 on unknown error trying to write, errno will carry over from + * write() call + */ +static ssize_t +ipc_write_message(int fd, const void *buf, size_t count) +{ + size_t written = 0; + + while (written < count) { + const ssize_t n = write(fd, (uint8_t *)buf + written, count - written); + + if (n == -1) { + if (errno == EAGAIN || errno == EWOULDBLOCK) + return written; + else if (errno == EINTR) + continue; + else + return n; + } + + written += n; + DEBUG("Wrote %zu/%zu to client at fd %d\n", written, count, fd); + } + + return written; +} + +/** + * Initialization for generic event message. This is used to allocate the yajl + * handle, set yajl options, and in the future any other initialization that + * should occur for event messages. + */ +static void +ipc_event_init_message(yajl_gen *gen) +{ + *gen = yajl_gen_alloc(NULL); + yajl_gen_config(*gen, yajl_gen_beautify, 1); +} + +/** + * Prepares buffers of IPC subscribers of specified event using buffer from yajl + * handle. + */ +static void +ipc_event_prepare_send_message(yajl_gen gen, IPCEvent event) +{ + const unsigned char *buffer; + size_t len = 0; + + yajl_gen_get_buf(gen, &buffer, &len); + len++; // For null char + + for (IPCClient *c = ipc_clients; c; c = c->next) { + if (c->subscriptions & event) { + DEBUG("Sending selected client change event to fd %d\n", c->fd); + ipc_prepare_send_message(c, IPC_TYPE_EVENT, len, (char *)buffer); + } + } + + // Not documented, but this frees temp_buffer + yajl_gen_free(gen); +} + +/** + * Initialization for generic reply message. This is used to allocate the yajl + * handle, set yajl options, and in the future any other initialization that + * should occur for reply messages. + */ +static void +ipc_reply_init_message(yajl_gen *gen) +{ + *gen = yajl_gen_alloc(NULL); + yajl_gen_config(*gen, yajl_gen_beautify, 1); +} + +/** + * Prepares the IPC client's buffer with a message using the buffer of the yajl + * handle. + */ +static void +ipc_reply_prepare_send_message(yajl_gen gen, IPCClient *c, + IPCMessageType msg_type) +{ + const unsigned char *buffer; + size_t len = 0; + + yajl_gen_get_buf(gen, &buffer, &len); + len++; // For null char + + ipc_prepare_send_message(c, msg_type, len, (const char *)buffer); + + // Not documented, but this frees temp_buffer + yajl_gen_free(gen); +} + +/** + * Find the IPCCommand with the specified name + * + * Returns 0 if a command with the specified name was found + * Returns -1 if a command with the specified name could not be found + */ +static int +ipc_get_ipc_command(const char *name, IPCCommand *ipc_command) +{ + for (int i = 0; i < ipc_commands_len; i++) { + if (strcmp(ipc_commands[i].name, name) == 0) { + *ipc_command = ipc_commands[i]; + return 0; + } + } + + return -1; +} + +/** + * Parse a IPC_TYPE_RUN_COMMAND message from a client. This function extracts + * the arguments, argument count, argument types, and command name and returns + * the parsed information as an IPCParsedCommand. If this function returns + * successfully, the parsed_command must be freed using + * ipc_free_parsed_command_members. + * + * Returns 0 if the message was successfully parsed + * Returns -1 otherwise + */ +static int +ipc_parse_run_command(char *msg, IPCParsedCommand *parsed_command) +{ + char error_buffer[1000]; + yajl_val parent = yajl_tree_parse(msg, error_buffer, 1000); + + if (parent == NULL) { + fputs("Failed to parse command from client\n", stderr); + fprintf(stderr, "%s\n", error_buffer); + fprintf(stderr, "Tried to parse: %s\n", msg); + return -1; + } + + // Format: + // { + // "command": "<command name>" + // "args": [ "arg1", "arg2", ... ] + // } + const char *command_path[] = {"command", 0}; + yajl_val command_val = yajl_tree_get(parent, command_path, yajl_t_string); + + if (command_val == NULL) { + fputs("No command key found in client message\n", stderr); + yajl_tree_free(parent); + return -1; + } + + const char *command_name = YAJL_GET_STRING(command_val); + size_t command_name_len = strlen(command_name); + parsed_command->name = (char *)malloc((command_name_len + 1) * sizeof(char)); + strcpy(parsed_command->name, command_name); + + DEBUG("Received command: %s\n", parsed_command->name); + + const char *args_path[] = {"args", 0}; + yajl_val args_val = yajl_tree_get(parent, args_path, yajl_t_array); + + if (args_val == NULL) { + fputs("No args key found in client message\n", stderr); + yajl_tree_free(parent); + return -1; + } + + unsigned int *argc = &parsed_command->argc; + Arg **args = &parsed_command->args; + ArgType **arg_types = &parsed_command->arg_types; + + *argc = args_val->u.array.len; + + // If no arguments are specified, make a dummy argument to pass to the + // function. This is just the way dwm's void(Arg*) functions are setup. + if (*argc == 0) { + *args = (Arg *)malloc(sizeof(Arg)); + *arg_types = (ArgType *)malloc(sizeof(ArgType)); + (*arg_types)[0] = ARG_TYPE_NONE; + (*args)[0].f = 0; + (*argc)++; + } else if (*argc > 0) { + *args = (Arg *)calloc(*argc, sizeof(Arg)); + *arg_types = (ArgType *)malloc(*argc * sizeof(ArgType)); + + for (int i = 0; i < *argc; i++) { + yajl_val arg_val = args_val->u.array.values[i]; + + if (YAJL_IS_NUMBER(arg_val)) { + if (YAJL_IS_INTEGER(arg_val)) { + // Any values below 0 must be a signed int + if (YAJL_GET_INTEGER(arg_val) < 0) { + (*args)[i].i = YAJL_GET_INTEGER(arg_val); + (*arg_types)[i] = ARG_TYPE_SINT; + DEBUG("i=%ld\n", (*args)[i].i); + // Any values above 0 should be an unsigned int + } else if (YAJL_GET_INTEGER(arg_val) >= 0) { + (*args)[i].ui = YAJL_GET_INTEGER(arg_val); + (*arg_types)[i] = ARG_TYPE_UINT; + DEBUG("ui=%ld\n", (*args)[i].i); + } + // If the number is not an integer, it must be a float + } else { + (*args)[i].f = (float)YAJL_GET_DOUBLE(arg_val); + (*arg_types)[i] = ARG_TYPE_FLOAT; + DEBUG("f=%f\n", (*args)[i].f); + // If argument is not a number, it must be a string + } + } else if (YAJL_IS_STRING(arg_val)) { + char *arg_s = YAJL_GET_STRING(arg_val); + size_t arg_s_size = (strlen(arg_s) + 1) * sizeof(char); + (*args)[i].v = (char *)malloc(arg_s_size); + (*arg_types)[i] = ARG_TYPE_STR; + strcpy((char *)(*args)[i].v, arg_s); + } + } + } + + yajl_tree_free(parent); + + return 0; +} + +/** + * Free the members of a IPCParsedCommand struct + */ +static void +ipc_free_parsed_command_members(IPCParsedCommand *command) +{ + for (int i = 0; i < command->argc; i++) { + if (command->arg_types[i] == ARG_TYPE_STR) free((void *)command->args[i].v); + } + free(command->args); + free(command->arg_types); + free(command->name); +} + +/** + * Check if the given arguments are the correct length and type. Also do any + * casting to correct the types. + * + * Returns 0 if the arguments were the correct length and types + * Returns -1 if the argument count doesn't match + * Returns -2 if the argument types don't match + */ +static int +ipc_validate_run_command(IPCParsedCommand *parsed, const IPCCommand actual) +{ + if (actual.argc != parsed->argc) return -1; + + for (int i = 0; i < parsed->argc; i++) { + ArgType ptype = parsed->arg_types[i]; + ArgType atype = actual.arg_types[i]; + + if (ptype != atype) { + if (ptype == ARG_TYPE_UINT && atype == ARG_TYPE_PTR) + // If this argument is supposed to be a void pointer, cast it + parsed->args[i].v = (void *)parsed->args[i].ui; + else if (ptype == ARG_TYPE_UINT && atype == ARG_TYPE_SINT) + // If this argument is supposed to be a signed int, cast it + parsed->args[i].i = parsed->args[i].ui; + else + return -2; + } + } + + return 0; +} + +/** + * Convert event name to their IPCEvent equivalent enum value + * + * Returns 0 if a valid event name was given + * Returns -1 otherwise + */ +static int +ipc_event_stoi(const char *subscription, IPCEvent *event) +{ + if (strcmp(subscription, "tag_change_event") == 0) + *event = IPC_EVENT_TAG_CHANGE; + else if (strcmp(subscription, "client_focus_change_event") == 0) + *event = IPC_EVENT_CLIENT_FOCUS_CHANGE; + else if (strcmp(subscription, "layout_change_event") == 0) + *event = IPC_EVENT_LAYOUT_CHANGE; + else if (strcmp(subscription, "monitor_focus_change_event") == 0) + *event = IPC_EVENT_MONITOR_FOCUS_CHANGE; + else if (strcmp(subscription, "focused_title_change_event") == 0) + *event = IPC_EVENT_FOCUSED_TITLE_CHANGE; + else if (strcmp(subscription, "focused_state_change_event") == 0) + *event = IPC_EVENT_FOCUSED_STATE_CHANGE; + else + return -1; + return 0; +} + +/** + * Parse a IPC_TYPE_SUBSCRIBE message from a client. This function extracts the + * event name and the subscription action from the message. + * + * Returns 0 if message was successfully parsed + * Returns -1 otherwise + */ +static int +ipc_parse_subscribe(const char *msg, IPCSubscriptionAction *subscribe, + IPCEvent *event) +{ + char error_buffer[100]; + yajl_val parent = yajl_tree_parse((char *)msg, error_buffer, 100); + + if (parent == NULL) { + fputs("Failed to parse command from client\n", stderr); + fprintf(stderr, "%s\n", error_buffer); + return -1; + } + + // Format: + // { + // "event": "<event name>" + // "action": "<subscribe|unsubscribe>" + // } + const char *event_path[] = {"event", 0}; + yajl_val event_val = yajl_tree_get(parent, event_path, yajl_t_string); + + if (event_val == NULL) { + fputs("No 'event' key found in client message\n", stderr); + return -1; + } + + const char *event_str = YAJL_GET_STRING(event_val); + DEBUG("Received event: %s\n", event_str); + + if (ipc_event_stoi(event_str, event) < 0) return -1; + + const char *action_path[] = {"action", 0}; + yajl_val action_val = yajl_tree_get(parent, action_path, yajl_t_string); + + if (action_val == NULL) { + fputs("No 'action' key found in client message\n", stderr); + return -1; + } + + const char *action = YAJL_GET_STRING(action_val); + + if (strcmp(action, "subscribe") == 0) + *subscribe = IPC_ACTION_SUBSCRIBE; + else if (strcmp(action, "unsubscribe") == 0) + *subscribe = IPC_ACTION_UNSUBSCRIBE; + else { + fputs("Invalid action specified for subscription\n", stderr); + return -1; + } + + yajl_tree_free(parent); + + return 0; +} + +/** + * Parse an IPC_TYPE_GET_DWM_CLIENT message from a client. This function + * extracts the window id from the message. + * + * Returns 0 if message was successfully parsed + * Returns -1 otherwise + */ +static int +ipc_parse_get_dwm_client(const char *msg, Window *win) +{ + char error_buffer[100]; + + yajl_val parent = yajl_tree_parse(msg, error_buffer, 100); + + if (parent == NULL) { + fputs("Failed to parse message from client\n", stderr); + fprintf(stderr, "%s\n", error_buffer); + return -1; + } + + // Format: + // { + // "client_window_id": <client window id> + // } + const char *win_path[] = {"client_window_id", 0}; + yajl_val win_val = yajl_tree_get(parent, win_path, yajl_t_number); + + if (win_val == NULL) { + fputs("No client window id found in client message\n", stderr); + return -1; + } + + *win = YAJL_GET_INTEGER(win_val); + + yajl_tree_free(parent); + + return 0; +} + +/** + * Called when an IPC_TYPE_RUN_COMMAND message is received from a client. This + * function parses, executes the given command, and prepares a reply message to + * the client indicating success/failure. + * + * NOTE: There is currently no check for argument validity beyond the number of + * arguments given and types of arguments. There is also no way to check if the + * function succeeded based on dwm's void(const Arg*) function types. Pointer + * arguments can cause crashes if they are not validated in the function itself. + * + * Returns 0 if message was successfully parsed + * Returns -1 on failure parsing message + */ +static int +ipc_run_command(IPCClient *ipc_client, char *msg) +{ + IPCParsedCommand parsed_command; + IPCCommand ipc_command; + + // Initialize struct + memset(&parsed_command, 0, sizeof(IPCParsedCommand)); + + if (ipc_parse_run_command(msg, &parsed_command) < 0) { + ipc_prepare_reply_failure(ipc_client, IPC_TYPE_RUN_COMMAND, + "Failed to parse run command"); + return -1; + } + + if (ipc_get_ipc_command(parsed_command.name, &ipc_command) < 0) { + ipc_prepare_reply_failure(ipc_client, IPC_TYPE_RUN_COMMAND, + "Command %s not found", parsed_command.name); + ipc_free_parsed_command_members(&parsed_command); + return -1; + } + + int res = ipc_validate_run_command(&parsed_command, ipc_command); + if (res < 0) { + if (res == -1) + ipc_prepare_reply_failure(ipc_client, IPC_TYPE_RUN_COMMAND, + "%u arguments provided, %u expected", + parsed_command.argc, ipc_command.argc); + else if (res == -2) + ipc_prepare_reply_failure(ipc_client, IPC_TYPE_RUN_COMMAND, + "Type mismatch"); + ipc_free_parsed_command_members(&parsed_command); + return -1; + } + + if (parsed_command.argc == 1) + ipc_command.func.single_param(parsed_command.args); + else if (parsed_command.argc > 1) + ipc_command.func.array_param(parsed_command.args, parsed_command.argc); + + DEBUG("Called function for command %s\n", parsed_command.name); + + ipc_free_parsed_command_members(&parsed_command); + + ipc_prepare_reply_success(ipc_client, IPC_TYPE_RUN_COMMAND); + return 0; +} + +/** + * Called when an IPC_TYPE_GET_MONITORS message is received from a client. It + * prepares a reply with the properties of all of the monitors in JSON. + */ +static void +ipc_get_monitors(IPCClient *c, Monitor *mons, Monitor *selmon) +{ + yajl_gen gen; + ipc_reply_init_message(&gen); + dump_monitors(gen, mons, selmon); + + ipc_reply_prepare_send_message(gen, c, IPC_TYPE_GET_MONITORS); +} + +/** + * Called when an IPC_TYPE_GET_TAGS message is received from a client. It + * prepares a reply with info about all the tags in JSON. + */ +static void +ipc_get_tags(IPCClient *c, const int tags_len) +{ + yajl_gen gen; + ipc_reply_init_message(&gen); + + dump_tags(gen, tags_len); + + ipc_reply_prepare_send_message(gen, c, IPC_TYPE_GET_TAGS); +} + +/** + * Called when an IPC_TYPE_GET_LAYOUTS message is received from a client. It + * prepares a reply with a JSON array of available layouts + */ +static void +ipc_get_layouts(IPCClient *c, const Layout layouts[], const int layouts_len) +{ + yajl_gen gen; + ipc_reply_init_message(&gen); + + dump_layouts(gen, layouts, layouts_len); + + ipc_reply_prepare_send_message(gen, c, IPC_TYPE_GET_LAYOUTS); +} + +/** + * Called when an IPC_TYPE_GET_DWM_CLIENT message is received from a client. It + * prepares a JSON reply with the properties of the client with the specified + * window XID. + * + * Returns 0 if the message was successfully parsed and if the client with the + * specified window XID was found + * Returns -1 if the message could not be parsed + */ +static int +ipc_get_dwm_client(IPCClient *ipc_client, const char *msg, const Monitor *mons) +{ + Window win; + + if (ipc_parse_get_dwm_client(msg, &win) < 0) return -1; + + // Find client with specified window XID + for (const Monitor *m = mons; m; m = m->next) + for (Client *c = m->clients; c; c = c->next) + if (c->win == win) { + yajl_gen gen; + ipc_reply_init_message(&gen); + + dump_client(gen, c); + + ipc_reply_prepare_send_message(gen, ipc_client, + IPC_TYPE_GET_DWM_CLIENT); + + return 0; + } + + ipc_prepare_reply_failure(ipc_client, IPC_TYPE_GET_DWM_CLIENT, + "Client with window id %d not found", win); + return -1; +} + +/** + * Called when an IPC_TYPE_SUBSCRIBE message is received from a client. It + * subscribes/unsubscribes the client from the specified event and replies with + * the result. + * + * Returns 0 if the message was successfully parsed. + * Returns -1 if the message could not be parsed + */ +static int +ipc_subscribe(IPCClient *c, const char *msg) +{ + IPCSubscriptionAction action = IPC_ACTION_SUBSCRIBE; + IPCEvent event = 0; + + if (ipc_parse_subscribe(msg, &action, &event)) { + ipc_prepare_reply_failure(c, IPC_TYPE_SUBSCRIBE, "Event does not exist"); + return -1; + } + + if (action == IPC_ACTION_SUBSCRIBE) { + DEBUG("Subscribing client on fd %d to %d\n", c->fd, event); + c->subscriptions |= event; + } else if (action == IPC_ACTION_UNSUBSCRIBE) { + DEBUG("Unsubscribing client on fd %d to %d\n", c->fd, event); + c->subscriptions ^= event; + } else { + ipc_prepare_reply_failure(c, IPC_TYPE_SUBSCRIBE, + "Invalid subscription action"); + return -1; + } + + ipc_prepare_reply_success(c, IPC_TYPE_SUBSCRIBE); + return 0; +} + +int +ipc_init(const char *socket_path, const int p_epoll_fd, IPCCommand commands[], + const int commands_len) +{ + // Initialize struct to 0 + memset(&sock_epoll_event, 0, sizeof(sock_epoll_event)); + + int socket_fd = ipc_create_socket(socket_path); + if (socket_fd < 0) return -1; + + ipc_commands = commands; + ipc_commands_len = commands_len; + + epoll_fd = p_epoll_fd; + + // Wake up to incoming connection requests + sock_epoll_event.data.fd = socket_fd; + sock_epoll_event.events = EPOLLIN; + if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, socket_fd, &sock_epoll_event)) { + fputs("Failed to add sock file descriptor to epoll", stderr); + return -1; + } + + return socket_fd; +} + +void +ipc_cleanup() +{ + IPCClient *c = ipc_clients; + // Free clients and their buffers + while (c) { + ipc_drop_client(c); + c = ipc_clients; + } + + // Stop waking up for socket events + epoll_ctl(epoll_fd, EPOLL_CTL_DEL, sock_fd, &sock_epoll_event); + + // Uninitialize all static variables + epoll_fd = -1; + sock_fd = -1; + ipc_commands = NULL; + ipc_commands_len = 0; + memset(&sock_epoll_event, 0, sizeof(struct epoll_event)); + memset(&sockaddr, 0, sizeof(struct sockaddr_un)); + + // Delete socket + unlink(sockaddr.sun_path); + + shutdown(sock_fd, SHUT_RDWR); + close(sock_fd); +} + +int +ipc_get_sock_fd() +{ + return sock_fd; +} + +IPCClient * +ipc_get_client(int fd) +{ + return ipc_list_get_client(ipc_clients, fd); +} + +int +ipc_is_client_registered(int fd) +{ + return (ipc_get_client(fd) != NULL); +} + +int +ipc_accept_client() +{ + int fd = -1; + + struct sockaddr_un client_addr; + socklen_t len = 0; + + // For portability clear the addr structure, since some implementations + // have nonstandard fields in the structure + memset(&client_addr, 0, sizeof(struct sockaddr_un)); + + fd = accept(sock_fd, (struct sockaddr *)&client_addr, &len); + if (fd < 0 && errno != EINTR) { + fputs("Failed to accept IPC connection from client", stderr); + return -1; + } + + if (fcntl(fd, F_SETFD, FD_CLOEXEC) < 0) { + shutdown(fd, SHUT_RDWR); + close(fd); + fputs("Failed to set flags on new client fd", stderr); + } + + IPCClient *nc = ipc_client_new(fd); + if (nc == NULL) return -1; + + // Wake up to messages from this client + nc->event.data.fd = fd; + nc->event.events = EPOLLIN | EPOLLHUP; + epoll_ctl(epoll_fd, EPOLL_CTL_ADD, fd, &nc->event); + + ipc_list_add_client(&ipc_clients, nc); + + DEBUG("%s%d\n", "New client at fd: ", fd); + + return fd; +} + +int +ipc_drop_client(IPCClient *c) +{ + int fd = c->fd; + shutdown(fd, SHUT_RDWR); + int res = close(fd); + + if (res == 0) { + struct epoll_event ev; + + // Stop waking up to messages from this client + epoll_ctl(epoll_fd, EPOLL_CTL_DEL, fd, &ev); + ipc_list_remove_client(&ipc_clients, c); + + free(c->buffer); + free(c); + + DEBUG("Successfully removed client on fd %d\n", fd); + } else if (res < 0 && res != EINTR) { + fprintf(stderr, "Failed to close fd %d\n", fd); + } + + return res; +} + +int +ipc_read_client(IPCClient *c, IPCMessageType *msg_type, uint32_t *msg_size, + char **msg) +{ + int fd = c->fd; + int ret = + ipc_recv_message(fd, (uint8_t *)msg_type, msg_size, (uint8_t **)msg); + + if (ret < 0) { + // This will happen if these errors occur while reading header + if (ret == -1 && + (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK)) + return -2; + + fprintf(stderr, "Error reading message: dropping client at fd %d\n", fd); + ipc_drop_client(c); + + return -1; + } + + // Make sure receive message is null terminated to avoid parsing issues + if (*msg_size > 0) { + size_t len = *msg_size; + nullterminate(msg, &len); + *msg_size = len; + } + + DEBUG("[fd %d] ", fd); + if (*msg_size > 0) + DEBUG("Received message: '%.*s' ", *msg_size, *msg); + else + DEBUG("Received empty message "); + DEBUG("Message type: %" PRIu8 " ", (uint8_t)*msg_type); + DEBUG("Message size: %" PRIu32 "\n", *msg_size); + + return 0; +} + +ssize_t +ipc_write_client(IPCClient *c) +{ + const ssize_t n = ipc_write_message(c->fd, c->buffer, c->buffer_size); + + if (n < 0) return n; + + // TODO: Deal with client timeouts + + if (n == c->buffer_size) { + c->buffer_size = 0; + free(c->buffer); + // No dangling pointers! + c->buffer = NULL; + // Stop waking up when client is ready to receive messages + if (c->event.events & EPOLLOUT) { + c->event.events -= EPOLLOUT; + epoll_ctl(epoll_fd, EPOLL_CTL_MOD, c->fd, &c->event); + } + return n; + } + + // Shift unwritten buffer to beginning of buffer and reallocate + c->buffer_size -= n; + memmove(c->buffer, c->buffer + n, c->buffer_size); + c->buffer = (char *)realloc(c->buffer, c->buffer_size); + + return n; +} + +void +ipc_prepare_send_message(IPCClient *c, const IPCMessageType msg_type, + const uint32_t msg_size, const char *msg) +{ + dwm_ipc_header_t header = { + .magic = IPC_MAGIC_ARR, .type = msg_type, .size = msg_size}; + + uint32_t header_size = sizeof(dwm_ipc_header_t); + uint32_t packet_size = header_size + msg_size; + + if (c->buffer == NULL) + c->buffer = (char *)malloc(c->buffer_size + packet_size); + else + c->buffer = (char *)realloc(c->buffer, c->buffer_size + packet_size); + + // Copy header to end of client buffer + memcpy(c->buffer + c->buffer_size, &header, header_size); + c->buffer_size += header_size; + + // Copy message to end of client buffer + memcpy(c->buffer + c->buffer_size, msg, msg_size); + c->buffer_size += msg_size; + + // Wake up when client is ready to receive messages + c->event.events |= EPOLLOUT; + epoll_ctl(epoll_fd, EPOLL_CTL_MOD, c->fd, &c->event); +} + +void +ipc_prepare_reply_failure(IPCClient *c, IPCMessageType msg_type, + const char *format, ...) +{ + yajl_gen gen; + va_list args; + + // Get output size + va_start(args, format); + size_t len = vsnprintf(NULL, 0, format, args); + va_end(args); + char *buffer = (char *)malloc((len + 1) * sizeof(char)); + + ipc_reply_init_message(&gen); + + va_start(args, format); + vsnprintf(buffer, len + 1, format, args); + va_end(args); + dump_error_message(gen, buffer); + + ipc_reply_prepare_send_message(gen, c, msg_type); + fprintf(stderr, "[fd %d] Error: %s\n", c->fd, buffer); + + free(buffer); +} + +void +ipc_prepare_reply_success(IPCClient *c, IPCMessageType msg_type) +{ + const char *success_msg = "{\"result\":\"success\"}"; + const size_t msg_len = strlen(success_msg) + 1; // +1 for null char + + ipc_prepare_send_message(c, msg_type, msg_len, success_msg); +} + +void +ipc_tag_change_event(int mon_num, TagState old_state, TagState new_state) +{ + yajl_gen gen; + ipc_event_init_message(&gen); + dump_tag_event(gen, mon_num, old_state, new_state); + ipc_event_prepare_send_message(gen, IPC_EVENT_TAG_CHANGE); +} + +void +ipc_client_focus_change_event(int mon_num, Client *old_client, + Client *new_client) +{ + yajl_gen gen; + ipc_event_init_message(&gen); + dump_client_focus_change_event(gen, old_client, new_client, mon_num); + ipc_event_prepare_send_message(gen, IPC_EVENT_CLIENT_FOCUS_CHANGE); +} + +void +ipc_layout_change_event(const int mon_num, const char *old_symbol, + const Layout *old_layout, const char *new_symbol, + const Layout *new_layout) +{ + yajl_gen gen; + ipc_event_init_message(&gen); + dump_layout_change_event(gen, mon_num, old_symbol, old_layout, new_symbol, + new_layout); + ipc_event_prepare_send_message(gen, IPC_EVENT_LAYOUT_CHANGE); +} + +void +ipc_monitor_focus_change_event(const int last_mon_num, const int new_mon_num) +{ + yajl_gen gen; + ipc_event_init_message(&gen); + dump_monitor_focus_change_event(gen, last_mon_num, new_mon_num); + ipc_event_prepare_send_message(gen, IPC_EVENT_MONITOR_FOCUS_CHANGE); +} + +void +ipc_focused_title_change_event(const int mon_num, const Window client_id, + const char *old_name, const char *new_name) +{ + yajl_gen gen; + ipc_event_init_message(&gen); + dump_focused_title_change_event(gen, mon_num, client_id, old_name, new_name); + ipc_event_prepare_send_message(gen, IPC_EVENT_FOCUSED_TITLE_CHANGE); +} + +void +ipc_focused_state_change_event(const int mon_num, const Window client_id, + const ClientState *old_state, + const ClientState *new_state) +{ + yajl_gen gen; + ipc_event_init_message(&gen); + dump_focused_state_change_event(gen, mon_num, client_id, old_state, + new_state); + ipc_event_prepare_send_message(gen, IPC_EVENT_FOCUSED_STATE_CHANGE); +} + +void +ipc_send_events(Monitor *mons, Monitor **lastselmon, Monitor *selmon) +{ + for (Monitor *m = mons; m; m = m->next) { + unsigned int urg = 0, occ = 0, tagset = 0; + + for (Client *c = m->clients; c; c = c->next) { + occ |= c->tags; + + if (c->isurgent) urg |= c->tags; + } + tagset = m->tagset[m->seltags]; + + TagState new_state = {.selected = tagset, .occupied = occ, .urgent = urg}; + + if (memcmp(&m->tagstate, &new_state, sizeof(TagState)) != 0) { + ipc_tag_change_event(m->num, m->tagstate, new_state); + m->tagstate = new_state; + } + + if (m->lastsel != m->sel) { + ipc_client_focus_change_event(m->num, m->lastsel, m->sel); + m->lastsel = m->sel; + } + + if (strcmp(m->ltsymbol, m->lastltsymbol) != 0 || + m->lastlt != m->lt[m->sellt]) { + ipc_layout_change_event(m->num, m->lastltsymbol, m->lastlt, m->ltsymbol, + m->lt[m->sellt]); + strcpy(m->lastltsymbol, m->ltsymbol); + m->lastlt = m->lt[m->sellt]; + } + + if (*lastselmon != selmon) { + if (*lastselmon != NULL) + ipc_monitor_focus_change_event((*lastselmon)->num, selmon->num); + *lastselmon = selmon; + } + + Client *sel = m->sel; + if (!sel) continue; + ClientState *o = &m->sel->prevstate; + ClientState n = {.oldstate = sel->oldstate, + .isfixed = sel->isfixed, + .isfloating = sel->isfloating, + .isfullscreen = sel->isfullscreen, + .isurgent = sel->isurgent, + .neverfocus = sel->neverfocus}; + if (memcmp(o, &n, sizeof(ClientState)) != 0) { + ipc_focused_state_change_event(m->num, m->sel->win, o, &n); + *o = n; + } + } +} + +int +ipc_handle_client_epoll_event(struct epoll_event *ev, Monitor *mons, + Monitor **lastselmon, Monitor *selmon, const int tags_len, + const Layout *layouts, const int layouts_len) +{ + int fd = ev->data.fd; + IPCClient *c = ipc_get_client(fd); + + if (ev->events & EPOLLHUP) { + DEBUG("EPOLLHUP received from client at fd %d\n", fd); + ipc_drop_client(c); + } else if (ev->events & EPOLLOUT) { + DEBUG("Sending message to client at fd %d...\n", fd); + if (c->buffer_size) ipc_write_client(c); + } else if (ev->events & EPOLLIN) { + IPCMessageType msg_type = 0; + uint32_t msg_size = 0; + char *msg = NULL; + + DEBUG("Received message from fd %d\n", fd); + if (ipc_read_client(c, &msg_type, &msg_size, &msg) < 0) return -1; + + if (msg_type == IPC_TYPE_GET_MONITORS) + ipc_get_monitors(c, mons, selmon); + else if (msg_type == IPC_TYPE_GET_TAGS) + ipc_get_tags(c, tags_len); + else if (msg_type == IPC_TYPE_GET_LAYOUTS) + ipc_get_layouts(c, layouts, layouts_len); + else if (msg_type == IPC_TYPE_RUN_COMMAND) { + if (ipc_run_command(c, msg) < 0) return -1; + ipc_send_events(mons, lastselmon, selmon); + } else if (msg_type == IPC_TYPE_GET_DWM_CLIENT) { + if (ipc_get_dwm_client(c, msg, mons) < 0) return -1; + } else if (msg_type == IPC_TYPE_SUBSCRIBE) { + if (ipc_subscribe(c, msg) < 0) return -1; + } else { + fprintf(stderr, "Invalid message type received from fd %d", fd); + ipc_prepare_reply_failure(c, msg_type, "Invalid message type: %d", + msg_type); + } + free(msg); + } else { + fprintf(stderr, "Epoll event returned %d from fd %d\n", ev->events, fd); + return -1; + } + + return 0; +} + +int +ipc_handle_socket_epoll_event(struct epoll_event *ev) +{ + if (!(ev->events & EPOLLIN)) return -1; + + // EPOLLIN means incoming client connection request + fputs("Received EPOLLIN event on socket\n", stderr); + int new_fd = ipc_accept_client(); + + return new_fd; +} + |