Implement keymap writing server-side

3 files changed, 96 insertions, 5 deletions

diff --git a/rcm-server-keymap.c b/rcm-server-keymap.c
index 6e45570..04dd1a4 100644
--- a/rcm-server-keymap.c
+++ b/rcm-server-keymap.c
@@ -438,6 +438,94 @@ keymaps_load(struct device *device)
 	return 0;
 }
 
+int
+keymap_write(struct keymap *keymap)
+{
+	_cleanup_close_ int dfd = -1;
+	_cleanup_close_ int fd = -1;
+	_cleanup_fclose_ FILE *file = NULL;
+	char *separator;
+	unsigned i;
+
+	separator = strrchr(keymap->id, '/');
+	if (!separator)
+		return -EINVAL;
+
+	/* FIXME: This is just a temporary location */
+	dfd = open("./keymaps", O_PATH | O_DIRECTORY);
+	if (dfd < 0)
+		return -errno;
+
+	*separator = '\0';
+	fd = openat(dfd, keymap->id, O_TMPFILE | O_WRONLY, 0644);
+	*separator = '/';
+	if (fd < 0)
+		return -errno;
+
+	/* https://sourceware.org/bugzilla/show_bug.cgi?id=17523 */
+	if (fchmod(fd, 0644) < 0)
+		return -errno;
+
+	int fdpath_len;
+	fdpath_len = snprintf(NULL, 0, "/proc/self/fd/%i", fd);
+	if (fdpath_len < 0)
+		return -errno;
+
+	char fdpath[fdpath_len + 1];
+	sprintf(fdpath, "/proc/self/fd/%d", fd);
+
+	file = fdopen(fd, "w");
+	if (!file)
+		return -errno;
+	else
+		fd = -1;
+
+	fprintf(file, "[Description]\n");
+	fprintf(file, "Name=%s\n", keymap->name);
+	fprintf(file, "Description=%s\n", keymap->description);
+	fprintf(file, "Rows=%u\n", keymap->rows);
+	fprintf(file, "Cols=%u\n", keymap->cols);
+	fprintf(file, "\n");
+
+	fprintf(file, "[Keymap]\n");
+	for (i = 0; i < keymap->keycode_count; i++) {
+		fprintf(file, "Map=%s:0x%08" PRIx64 ":%s\n",
+			keymap->keycodes[i].protocol,
+			keymap->keycodes[i].scancode,
+			keymap->keycodes[i].keycode);
+	}
+	fprintf(file, "\n");
+
+	fprintf(file, "[Layout]\n");
+	for (i = 0; i < (keymap->rows * keymap->cols); i++) {
+		if (keymap->layout[i])
+			fprintf(file, "Button=%s\n", keymap->layout[i]->keycode);
+		else
+			fprintf(file, "Button=Blank\n");
+	}
+
+	fflush(file);
+
+	if (ferror(file))
+		return errno ? -errno : -EIO;
+
+	char tmppath[strlen(keymap->id) + strlen(".tmp") + 1];
+	sprintf(tmppath, "%s.tmp", keymap->id);
+
+	if (linkat(AT_FDCWD, fdpath, dfd, tmppath, AT_SYMLINK_FOLLOW) < 0) {
+		printf("linkat failed: %i - %s\n", errno, strerror(errno));
+		return -errno;
+	}
+
+	if (renameat(dfd, tmppath, dfd, keymap->id) < 0) {
+		int r = -errno;
+		unlinkat(dfd, tmppath, 0);
+		return r;
+	}
+
+	return 0;
+}
+
 void
 keymap_free(struct keymap *keymap)
 {
diff --git a/rcm-server-keymap.h b/rcm-server-keymap.h
index 03badb1..a68a1fd 100644
--- a/rcm-server-keymap.h
+++ b/rcm-server-keymap.h
@@ -23,6 +23,8 @@ struct keymap *find_keymap_by_id(struct device *dev, const char *id);
 
 int keymaps_load(struct device *device);
 
+int keymap_write(struct keymap *keymap);
+
 void keymap_free(struct keymap *keymap);
 
 #endif
diff --git a/rcm-server-main.c b/rcm-server-main.c
index 0623a01..cde13a0 100644
--- a/rcm-server-main.c
+++ b/rcm-server-main.c
@@ -587,29 +587,30 @@ method_setkeymap(sd_bus_message *m, void *userdata, sd_bus_error *error)
 
 	new_keymap->layout = zmalloc(sizeof(struct keycode *) * cols * rows);
 	if (!new_keymap->layout) {
-		keymap_free(new_keymap);
 		r = -ENOMEM;
 		goto out;
 	}
 
 	r = method_setkeymap_parse_dbus_msg(m, new_keymap, NULL, NULL, NULL, NULL);
-	if (r < 0) {
-		keymap_free(new_keymap);
+	if (r < 0)
 		goto out;
-	}
 
 	printf("\tUpdated keymap: name (%s), desc (%s), keycodes(%u), rows(%u), cols(%u)\n",
 	       new_keymap->name, new_keymap->description,
 	       new_keymap->keycode_count,
 	       new_keymap->rows, new_keymap->cols);
 
-	/* FIXME: Write to disk */
+	r = keymap_write(new_keymap);
+	if (r < 0)
+		goto out;
+
 	list_replace(&old_keymap->list, &new_keymap->list);
 	keymap_free(old_keymap);
 
 	return sd_bus_reply_method_return(m, NULL);
 
 out:
+	keymap_free(new_keymap);
 	return sd_bus_error_set_errno(error, r);
 }