Rework get_clipboard implementation

3 files changed, 413 insertions, 86 deletions

diff --git a/sway/CMakeLists.txt b/sway/CMakeLists.txt
index bf0b2e7f..11bec4df 100644
--- a/sway/CMakeLists.txt
+++ b/sway/CMakeLists.txt
@@ -19,6 +19,7 @@ file(GLOB cmds
 add_executable(sway
 	commands.c
 	${cmds}
+	base64.c
 	config.c
 	container.c
 	criteria.c
@@ -35,7 +36,7 @@ add_executable(sway
 	output.c
 	workspace.c
 	border.c
-    security.c
+	security.c
 )
 
 add_definitions(
diff --git a/sway/base64.c b/sway/base64.c
new file mode 100644
index 00000000..0d51b5c7
--- /dev/null
+++ b/sway/base64.c
@@ -0,0 +1,221 @@
+/*
+ * Adapted from https://github.com/littlstar/b64.c
+ * License under the MIT License:
+ * Copyright (c) 2014 Little Star Media, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <ctype.h>
+#include <stdlib.h>
+#include "util.h"
+
+static const char b64_table[] = {
+	'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
+	'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
+	'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
+	'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
+	'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
+	'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
+	'w', 'x', 'y', 'z', '0', '1', '2', '3',
+	'4', '5', '6', '7', '8', '9', '+', '/'
+};
+
+char *b64_encode(const char *src, size_t len, size_t *flen) {
+	int i = 0;
+	int j = 0;
+	char *enc = NULL;
+	size_t size = len * 4 / 3;
+	size_t idx = 0;
+	unsigned char buf[4];
+	char tmp[3];
+
+	// alloc
+	enc = (char *) malloc(size + 1);
+	if (NULL == enc) { return NULL; }
+
+	// parse until end of source
+	while (len--) {
+		// read up to 3 bytes at a time into `tmp'
+		tmp[i++] = *(src++);
+
+		// if 3 bytes read then encode into `buf'
+		if (3 == i) {
+			buf[0] = (tmp[0] & 0xfc) >> 2;
+			buf[1] = ((tmp[0] & 0x03) << 4) + ((tmp[1] & 0xf0) >> 4);
+			buf[2] = ((tmp[1] & 0x0f) << 2) + ((tmp[2] & 0xc0) >> 6);
+			buf[3] = tmp[2] & 0x3f;
+
+			// shouldn't really happen
+			if (idx + 4 > size) {
+				size += 16;
+				enc = (char *) realloc(enc, size + 1);
+			}
+			for (i = 0; i < 4; ++i) {
+				enc[idx++] = b64_table[buf[i]];
+			}
+
+			// reset index
+			i = 0;
+		}
+	}
+
+	// remainder
+	if (i > 0) {
+		// fill `tmp' with `\0' at most 3 times
+		for (j = i; j < 3; ++j) {
+			tmp[j] = '\0';
+		}
+
+		// perform same codec as above
+		buf[0] = (tmp[0] & 0xfc) >> 2;
+		buf[1] = ((tmp[0] & 0x03) << 4) + ((tmp[1] & 0xf0) >> 4);
+		buf[2] = ((tmp[1] & 0x0f) << 2) + ((tmp[2] & 0xc0) >> 6);
+		buf[3] = tmp[2] & 0x3f;
+
+		// perform same write to `enc` with new allocation
+		size_t delta = (i > 3 ? 0 : 3 - i) + (j > i + 1 ? 0 : i + 1 - j);
+		if (idx + delta > size) {
+			size += delta;
+			enc = (char *) realloc(enc, size + 1);
+		}
+		for (j = 0; (j < i + 1); ++j) {
+			enc[idx++] = b64_table[buf[j]];
+		}
+
+		// while there is still a remainder
+		// append `=' to `enc'
+		while ((i++ < 3)) {
+			enc[idx++] = '=';
+		}
+	}
+
+	enc[idx] = '\0';
+
+	if (flen)
+		*flen = size;
+	return enc;
+}
+
+unsigned char *b64_decode(const char *src, size_t len, size_t *decsize) {
+	int i = 0;
+	int j = 0;
+	int l = 0;
+	// max size estimate
+	size_t size = len * 3 / 4;
+	size_t idx = 0;
+	unsigned char *dec = NULL;
+	unsigned char buf[3];
+	unsigned char tmp[4];
+
+	// alloc
+	dec = (unsigned char *) malloc(size + 1);
+	if (NULL == dec) { return NULL; }
+
+	// parse until end of source
+	while (len--) {
+		if (isspace(src[j])) { j++; continue; }
+		// break if char is `=' or not base64 char
+		if ('=' == src[j]) { break; }
+		if (!(isalnum(src[j]) || '+' == src[j] || '/' == src[j])) { break; }
+
+		// read up to 4 bytes at a time into `tmp'
+		tmp[i++] = src[j++];
+
+		// if 4 bytes read then decode into `buf'
+		if (4 == i) {
+			// translate values in `tmp' from table
+			for (i = 0; i < 4; ++i) {
+				// find translation char in `b64_table'
+				for (l = 0; l < 64; ++l) {
+					if (tmp[i] == b64_table[l]) {
+						tmp[i] = l;
+						break;
+					}
+				}
+			}
+
+			// decode
+			buf[0] = (tmp[0] << 2) + ((tmp[1] & 0x30) >> 4);
+			buf[1] = ((tmp[1] & 0xf) << 4) + ((tmp[2] & 0x3c) >> 2);
+			buf[2] = ((tmp[2] & 0x3) << 6) + tmp[3];
+
+			// unlikely
+			if (idx + 3 > size) {
+				size += 16;
+				dec = (unsigned char *) realloc(dec, size + 1);
+			}
+			if (dec != NULL){
+				for (i = 0; i < 3; ++i) {
+					dec[idx++] = buf[i];
+				}
+			} else {
+				return NULL;
+			}
+
+			// reset
+			i = 0;
+		}
+	}
+
+	// remainder
+	if (i > 0) {
+		// fill `tmp' with `\0' at most 4 times
+		for (j = i; j < 4; ++j) {
+			tmp[j] = '\0';
+		}
+
+		// translate remainder
+		for (j = 0; j < 4; ++j) {
+			// find translation char in `b64_table'
+			for (l = 0; l < 64; ++l) {
+				if (tmp[j] == b64_table[l]) {
+					tmp[j] = l;
+					break;
+				}
+			}
+		}
+
+		// decode remainder
+		buf[0] = (tmp[0] << 2) + ((tmp[1] & 0x30) >> 4);
+		buf[1] = ((tmp[1] & 0xf) << 4) + ((tmp[2] & 0x3c) >> 2);
+		buf[2] = ((tmp[2] & 0x3) << 6) + tmp[3];
+
+		// write remainer decoded buffer to `dec'
+		if (idx + (i - 1) > size) {
+			size += 16;
+			dec = (unsigned char *) realloc(dec, size + 1);
+		}
+		if (dec != NULL){
+			for (j = 0; (j < i - 1); ++j) {
+				dec[idx++] = buf[j];
+			}
+		} else {
+			return NULL;
+		}
+	}
+
+	dec[idx] = '\0';
+	// Return back the size of decoded string if demanded.
+	if (decsize != NULL) {
+		*decsize = size;
+	}
+
+	return dec;
+}
diff --git a/sway/ipc-server.c b/sway/ipc-server.c
index b6268404..70692f64 100644
--- a/sway/ipc-server.c
+++ b/sway/ipc-server.c
@@ -1,5 +1,6 @@
 // See https://i3wm.org/docs/ipc.html for protocol information
 
+#define _XOPEN_SOURCE 700
 #include <errno.h>
 #include <string.h>
 #include <sys/socket.h>
@@ -56,8 +57,11 @@ struct get_pixels_request {
 };
 
 struct get_clipboard_request {
-   struct ipc_client *client;
-   struct wlc_event_source *event_source;
+	struct ipc_client *client;
+	json_object *json;
+	struct wlc_event_source *event_source;
+	char *type;
+	unsigned int *pending;
 };
 
 struct sockaddr_un *ipc_user_sockaddr(void);
@@ -327,44 +331,201 @@ void ipc_get_pixels(wlc_handle output) {
 	ipc_get_pixel_requests = unhandled;
 }
 
-static int ipc_selection_data_cb(int fd, uint32_t mask, void *data)
-{
+static int ipc_selection_data_cb(int fd, uint32_t mask, void *data) {
 	assert(data);
-	struct get_clipboard_request *req = (struct get_clipboard_request*) data;
+	struct get_clipboard_request *req = (struct get_clipboard_request *)data;
 
 	if (mask & WLC_EVENT_ERROR) {
 		sway_log(L_ERROR, "Selection data fd error");
-		const char *error = "{ \"success\": false, \"error\": "
-			"\"Could not receive text data from clipboard\" }";
-		ipc_send_reply(req->client, error, (uint32_t)strlen(error));
 		goto cleanup;
 	}
 
-	if (mask & WLC_EVENT_READABLE) {
-		char buf[512];
-		int ret = read(fd, buf, 511);
-		if (ret < 0) {
-			sway_log_errno(L_ERROR, "Reading from selection data fd failed");
-			const char *error = "{ \"success\": false, \"error\": "
-				"\"Could not receive text data from clipboard\" }";
-			ipc_send_reply(req->client, error, (uint32_t)strlen(error));
-			goto cleanup;
+	if (mask & WLC_EVENT_READABLE || true) {
+		static const int step_size = 512;
+		char *data = NULL;
+		int ret = 0;
+		int current = 0;
+
+		// read data as long as there is data avilable
+		// grow the buffer step_size in every iteration
+		do {
+			if (data == NULL) {
+				data = malloc(step_size);
+			} else {
+				data = realloc(data, current + step_size);
+			}
+
+			ret = read(fd, data + current, step_size - 1);
+			if (ret < 0) {
+				sway_log_errno(L_ERROR, "Reading from selection data fd failed");
+				goto cleanup;
+			}
+
+			current += ret;
+		} while (ret == step_size - 1);
+
+		data[current] = '\0';
+
+		if (strncmp(req->type, "text/", 5) == 0) {
+			json_object_object_add(req->json, req->type,
+				json_object_new_string(data));
+		} else {
+			size_t outlen;
+			char *b64 = b64_encode(data, current, &outlen);
+			json_object_object_add(req->json, req->type,
+					json_object_new_string(b64));
+			free(b64);
 		}
 
-		buf[ret] = '\0';
-		json_object *obj = json_object_new_object();
-		json_object_object_add(obj, "success", json_object_new_boolean(true));
-		json_object_object_add(obj, "content", json_object_new_string(buf));
-		const char *str = json_object_to_json_string(obj);
+		free(data);
+	} else {
+		return 0; // TODO
+	}
+
+cleanup:
+	close(fd);
+
+	if (--(*req->pending) == 0) {
+		const char *str = json_object_to_json_string(req->json);
 		ipc_send_reply(req->client, str, (uint32_t)strlen(str));
+		json_object_put(req->json);
+	}
+
+	free(req->type);
+	wlc_event_source_remove(req->event_source);
+	free(req);
+	return 0;
+}
+
+// greedy wildcard (only "*") matching
+bool mime_type_matches(const char *mime_type, const char *pattern) {
+	const char* wildcard = NULL;
+	while (*mime_type && *pattern) {
+		if (*pattern == '*' && !wildcard) {
+			wildcard = pattern;
+			++pattern;
+		}
+
+		if (*mime_type != *pattern) {
+			if (!wildcard)
+				return false;
+
+			pattern = wildcard;
+			++mime_type;
+			continue;
+		}
+
+		++mime_type;
+		++pattern;
+	}
+
+	while (*pattern == '*') {
+		++pattern;
+	}
+
+	return (*mime_type == *pattern);
+}
+
+void ipc_get_clipboard(struct ipc_client *client, char *buf) {
+	static const char *error_json = "{ \"success\": false, \"error\": "
+		"\"Failed to retrieve clipboard data\" }";
+
+	size_t size;
+	const char **types = wlc_get_selection_types(&size);
+	if (client->payload_length == 0) {
+		json_object *obj = json_object_new_array();
+		for (size_t i = 0; i < size; ++i) {
+			json_object_array_add(obj, json_object_new_string(types[i]));
+		}
+
+		const char *str = json_object_to_json_string(obj);
+		ipc_send_reply(client, str, strlen(str));
 		json_object_put(obj);
+		return;
+	}
+
+	unescape_string(buf);
+	strip_quotes(buf);
+	list_t *requested = split_string(buf, " ");
+	json_object *json = json_object_new_object();
+	unsigned int *pending = malloc(sizeof(unsigned int));
+	*pending = 0;
+
+	for (size_t l = 0; l < (size_t) requested->length; ++l) {
+		const char *pattern = requested->items[l];
+		bool found = false;
+		for (size_t i = 0; i < size; ++i) {
+			if (mime_type_matches(types[i], pattern)) {
+				found = true;
+
+				struct get_clipboard_request *req = malloc(sizeof(*req));
+				if (!req) {
+					sway_log(L_ERROR, "Cannot allocate get_clipboard_request");
+					goto data_error;
+				}
+
+				int pipes[2];
+				if (pipe(pipes) == -1) {
+					sway_log_errno(L_ERROR, "pipe call failed");
+					free(req);
+					goto data_error;
+				}
+
+				fcntl(pipes[0], F_SETFD, FD_CLOEXEC | O_NONBLOCK);
+				fcntl(pipes[1], F_SETFD, FD_CLOEXEC | O_NONBLOCK);
+
+				if (!wlc_get_selection_data(types[i], pipes[1])) {
+					close(pipes[0]);
+					close(pipes[1]);
+					free(req);
+					sway_log(L_ERROR, "wlc_get_selection_data failed");
+					goto data_error;
+				}
+
+				(*pending)++;
+
+				req->client = client;
+				req->type = strdup(types[i]);
+				req->json = json;
+				req->pending = pending;
+				req->event_source = wlc_event_loop_add_fd(pipes[0],
+					WLC_EVENT_READABLE | WLC_EVENT_ERROR | WLC_EVENT_HANGUP,
+					&ipc_selection_data_cb, req);
+
+				// NOTE: remove this goto to enable retrieving multiple
+				// targets at once. The whole implementation is already
+				// made for it. The only reason it was disabled
+				// at the time of writing is that neither wlc's xselection
+				// implementation nor (apparently) gtk on wayland supports
+				// multiple send requests at the same time which makes
+				// every request except the last one fail (and therefore
+				// return empty data)
+				goto cleanup;
+			}
+		}
+
+		if (!found) {
+			sway_log(L_INFO, "Invalid clipboard type %s requested", pattern);
+		}
 	}
 
+	if (*pending == 0) {
+		static const char *empty = "[]";
+		ipc_send_reply(client, empty, (uint32_t)strlen(empty));
+		free(json);
+		free(pending);
+	}
+
+	goto cleanup;
+
+data_error:
+	ipc_send_reply(client, error_json, (uint32_t)strlen(error_json));
+	free(json);
+	free(pending);
+
 cleanup:
-   wlc_event_source_remove(req->event_source);
-   close(fd);
-   free(req);
-   return 0;
+	list_free(requested);
+	free(types);
 }
 
 void ipc_client_handle_command(struct ipc_client *client) {
@@ -610,69 +771,13 @@ void ipc_client_handle_command(struct ipc_client *client) {
 		goto exit_cleanup;
 	}
 
-   case IPC_GET_CLIPBOARD:
-   {
+	case IPC_GET_CLIPBOARD:
+	{
 		if (!(client->security_policy & IPC_FEATURE_GET_CLIPBOARD)) {
 			goto exit_denied;
 		}
 
-		size_t size;
-		const char **types = wlc_get_selection_types(&size);
-		const char *type = NULL;
-		if (types == NULL || size == 0) {
-			const char *error = "{ \"success\": false, \"error\": "
-				"\"Empty clipboard\" }";
-			ipc_send_reply(client, error, (uint32_t)strlen(error));
-			goto exit_cleanup;
-		}
-
-		for (size_t i = 0; i < size; ++i) {
-			if (strcmp(types[i], "text/plain;charset=utf-8") == 0
-					|| strcmp(types[i], "text/plain") == 0) {
-				type = types[i];
-				break;
-			}
-		}
-
-		if (type) {
-			struct get_clipboard_request *req = malloc(sizeof(*req));
-			if (!req) {
-				sway_log(L_ERROR, "Unable to allocate get_clipboard_request");
-				goto clipboard_error;
-			}
-
-			int pipes[2];
-			if (pipe(pipes) == -1) {
-				sway_log_errno(L_ERROR, "pipe call failed");
-				free(req);
-				goto clipboard_error;
-			}
-
-			fcntl(pipes[0], F_SETFD, FD_CLOEXEC | O_NONBLOCK);
-			fcntl(pipes[1], F_SETFD, FD_CLOEXEC | O_NONBLOCK);
-			if (!wlc_get_selection_data(type, pipes[1])) {
-				close(pipes[0]);
-				close(pipes[1]);
-				free(req);
-				sway_log(L_ERROR, "wlc_get_selection_data failed");
-				goto clipboard_error;
-			}
-
-			req->client = client;
-			req->event_source = wlc_event_loop_add_fd(pipes[0],
-				WLC_EVENT_READABLE | WLC_EVENT_ERROR | WLC_EVENT_HANGUP,
-				&ipc_selection_data_cb, req);
-			free(types);
-			goto exit_cleanup;
-		}
-
-clipboard_error:
-		sway_log(L_INFO, "Clipboard has to text data");
-		const char *error = "{ \"success\": false, \"error\": "
-			"\"Could not receive text data from clipboard\" }";
-		ipc_send_reply(client, error, (uint32_t)strlen(error));
-
-		free(types);
+		ipc_get_clipboard(client, buf);
 		goto exit_cleanup;
 	}