Move dbus code to a separate process to allow gpu-screen-recorder to use cap_sys_nice for better recording performance on amd

dbus/client/dbus_client.c

@@ -0,0 +1,265 @@
+#include "dbus_client.h"
+#include "../protocol.h"
+
+#include <sys/socket.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <poll.h>
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+
+// TODO: Error checking for write/read
+
+static bool gsr_dbus_client_wait_for_startup(gsr_dbus_client *self) {
+    struct pollfd poll_fd = {
+        .fd = self->socket_pair[0],
+        .events = POLLIN,
+        .revents = 0
+    };
+    for(;;) {
+        int poll_res = poll(&poll_fd, 1, 100);
+        if(poll_res > 0 && (poll_fd.revents & POLLIN)) {
+            char msg;
+            read(self->socket_pair[0], &msg, 1);
+            return true;
+        } else {
+            int status = 0;
+            int wait_result = waitpid(self->pid, &status, WNOHANG);
+            if(wait_result != 0) {
+                int exit_code = -1;
+                if(WIFEXITED(status))
+                    exit_code = WEXITSTATUS(status);
+                fprintf(stderr, "gsr error: gsr_dbus_client_init: server side or never started, exit code: %d\n", exit_code);
+                self->pid = 0;
+                return false;
+            }
+        }
+    }
+}
+
+bool gsr_dbus_client_init(gsr_dbus_client *self, const char *screencast_restore_token) {
+    memset(self, 0, sizeof(*self));
+
+    if(socketpair(AF_UNIX, SOCK_STREAM, 0, self->socket_pair) == -1) {
+        fprintf(stderr, "gsr error: gsr_dbus_client_init: socketpair failed, error: %s\n", strerror(errno));
+        return false;
+    }
+
+    if(screencast_restore_token) {
+        self->screencast_restore_token = strdup(screencast_restore_token);
+        if(!self->screencast_restore_token) {
+            fprintf(stderr, "gsr error: gsr_dbus_client_init: failed to clone restore token\n");
+            gsr_dbus_client_deinit(self);
+            return false;
+        }
+    }
+
+    self->pid = fork();
+    if(self->pid == -1) {
+        fprintf(stderr, "gsr error: gsr_dbus_client_init: failed to fork process\n");
+        gsr_dbus_client_deinit(self);
+        return false;
+    } else if(self->pid == 0) { /* child */
+        char socket_pair_server_str[32];
+        snprintf(socket_pair_server_str, sizeof(socket_pair_server_str), "%d", self->socket_pair[1]);
+
+        const char *args[] = { "gsr-dbus-server", socket_pair_server_str, self->screencast_restore_token ? self->screencast_restore_token : "", NULL };
+        execvp(args[0], (char *const*)args);
+
+        fprintf(stderr, "gsr error: gsr_dbus_client_init: execvp failed, error: %s\n", strerror(errno));
+        _exit(127);
+    } else { /* parent */
+        if(!gsr_dbus_client_wait_for_startup(self)) {
+            gsr_dbus_client_deinit(self);
+            return false;
+        }
+    }
+
+    return true;
+}
+
+void gsr_dbus_client_deinit(gsr_dbus_client *self) {
+    for(int i = 0; i < 2; ++i) {
+        if(self->socket_pair[i] > 0) {
+            close(self->socket_pair[i]);
+            self->socket_pair[i] = -1;
+        }
+    }
+
+    if(self->screencast_restore_token) {
+        free(self->screencast_restore_token);
+        self->screencast_restore_token = NULL;
+    }
+
+    if(self->pid > 0) {
+        kill(self->pid, SIGKILL);
+        int status = 0;
+        waitpid(self->pid, &status, 0);
+        self->pid = 0;
+    }
+}
+
+int gsr_dbus_client_screencast_create_session(gsr_dbus_client *self, char *session_handle, size_t session_handle_size) {
+    const gsr_dbus_request_message request = {
+        .protocol_version = GSR_DBUS_PROTOCOL_VERSION,
+        .type = GSR_DBUS_MESSAGE_REQ_CREATE_SESSION,
+        .create_session = (gsr_dbus_message_req_create_session) {}
+    };
+    write(self->socket_pair[0], &request, sizeof(request));
+
+    gsr_dbus_response_message response = {0};
+    read(self->socket_pair[0], &response, sizeof(response));
+
+    if(response.protocol_version != GSR_DBUS_PROTOCOL_VERSION) {
+        fprintf(stderr, "gsr error: gsr_dbus_client_screencast_create_session: server uses protocol version %d while the client is using protocol version %d", response.protocol_version, GSR_DBUS_PROTOCOL_VERSION);
+        return -1;
+    }
+
+    if(response.type == GSR_DBUS_MESSAGE_RESP_ERROR) {
+        fprintf(stderr, "gsr error: gsr_dbus_client_screencast_create_session: server return error: %s (%d)\n", response.error.message, (int)response.error.error_code);
+        return response.error.error_code;
+    }
+
+    if(response.type != GSR_DBUS_MESSAGE_RESP_CREATE_SESSION) {
+        fprintf(stderr, "gsr error: gsr_dbus_client_screencast_create_session: received incorrect response type. Expected %d got %d\n", GSR_DBUS_MESSAGE_RESP_CREATE_SESSION, response.type);
+        return -1;
+    }
+
+    snprintf(session_handle, session_handle_size, "%s", response.create_session.session_handle);
+    return 0;
+}
+
+int gsr_dbus_client_screencast_select_sources(gsr_dbus_client *self, const char *session_handle, uint32_t capture_type, uint32_t cursor_mode) {
+    gsr_dbus_request_message request = {
+        .protocol_version = GSR_DBUS_PROTOCOL_VERSION,
+        .type = GSR_DBUS_MESSAGE_REQ_SELECT_SOURCES,
+        .select_sources = (gsr_dbus_message_req_select_sources) {
+            .capture_type = capture_type,
+            .cursor_mode = cursor_mode
+        }
+    };
+    snprintf(request.select_sources.session_handle, sizeof(request.select_sources.session_handle), "%s", session_handle);
+    write(self->socket_pair[0], &request, sizeof(request));
+
+    gsr_dbus_response_message response = {0};
+    read(self->socket_pair[0], &response, sizeof(response));
+
+    if(response.protocol_version != GSR_DBUS_PROTOCOL_VERSION) {
+        fprintf(stderr, "gsr error: gsr_dbus_client_screencast_select_sources: server uses protocol version %d while the client is using protocol version %d", response.protocol_version, GSR_DBUS_PROTOCOL_VERSION);
+        return -1;
+    }
+
+    if(response.type == GSR_DBUS_MESSAGE_RESP_ERROR) {
+        fprintf(stderr, "gsr error: gsr_dbus_client_screencast_select_sources: server return error: %s (%d)\n", response.error.message, (int)response.error.error_code);
+        return response.error.error_code;
+    }
+
+    if(response.type != GSR_DBUS_MESSAGE_RESP_SELECT_SOURCES) {
+        fprintf(stderr, "gsr error: gsr_dbus_client_screencast_select_sources: received incorrect response type. Expected %d got %d\n", GSR_DBUS_MESSAGE_RESP_SELECT_SOURCES, response.type);
+        return -1;
+    }
+
+    return 0;
+}
+
+int gsr_dbus_client_screencast_start(gsr_dbus_client *self, const char *session_handle, uint32_t *pipewire_node) {
+    *pipewire_node = 0;
+
+    gsr_dbus_request_message request = {
+        .protocol_version = GSR_DBUS_PROTOCOL_VERSION,
+        .type = GSR_DBUS_MESSAGE_REQ_START,
+        .start = (gsr_dbus_message_req_start) {}
+    };
+    snprintf(request.start.session_handle, sizeof(request.start.session_handle), "%s", session_handle);
+    write(self->socket_pair[0], &request, sizeof(request));
+
+    gsr_dbus_response_message response = {0};
+    read(self->socket_pair[0], &response, sizeof(response));
+
+    if(response.protocol_version != GSR_DBUS_PROTOCOL_VERSION) {
+        fprintf(stderr, "gsr error: gsr_dbus_client_screencast_start: server uses protocol version %d while the client is using protocol version %d", response.protocol_version, GSR_DBUS_PROTOCOL_VERSION);
+        return -1;
+    }
+
+    if(response.type == GSR_DBUS_MESSAGE_RESP_ERROR) {
+        fprintf(stderr, "gsr error: gsr_dbus_client_screencast_start: server return error: %s (%d)\n", response.error.message, (int)response.error.error_code);
+        return response.error.error_code;
+    }
+
+    if(response.type != GSR_DBUS_MESSAGE_RESP_START) {
+        fprintf(stderr, "gsr error: gsr_dbus_client_screencast_start: received incorrect response type. Expected %d got %d\n", GSR_DBUS_MESSAGE_RESP_START, response.type);
+        return -1;
+    }
+
+    if(self->screencast_restore_token) {
+        free(self->screencast_restore_token);
+        if(response.start.restore_token[0] == '\0')
+            self->screencast_restore_token = NULL;
+        else
+            self->screencast_restore_token = strdup(response.start.restore_token);
+    }
+
+    *pipewire_node = response.start.pipewire_node;
+    return 0;
+}
+
+bool gsr_dbus_client_screencast_open_pipewire_remote(gsr_dbus_client *self, const char *session_handle, int *pipewire_fd) {
+    *pipewire_fd = 0;
+
+    gsr_dbus_request_message request = {
+        .protocol_version = GSR_DBUS_PROTOCOL_VERSION,
+        .type = GSR_DBUS_MESSAGE_REQ_OPEN_PIPEWIRE_REMOTE,
+        .open_pipewire_remote = (gsr_dbus_message_req_open_pipewire_remote) {}
+    };
+    snprintf(request.open_pipewire_remote.session_handle, sizeof(request.open_pipewire_remote.session_handle), "%s", session_handle);
+    write(self->socket_pair[0], &request, sizeof(request));
+
+    gsr_dbus_response_message response = {0};
+    struct iovec iov = {
+        .iov_base = &response,
+        .iov_len = sizeof(response)
+    };
+
+    char msg_control[CMSG_SPACE(sizeof(int))];
+
+    struct msghdr message = {
+        .msg_iov = &iov,
+        .msg_iovlen = 1,
+        .msg_control = msg_control,
+        .msg_controllen = sizeof(msg_control)
+    };
+
+    const int bla = recvmsg(self->socket_pair[0], &message, MSG_WAITALL);
+    (void)bla;
+
+    if(response.protocol_version != GSR_DBUS_PROTOCOL_VERSION) {
+        fprintf(stderr, "gsr error: gsr_dbus_client_screencast_open_pipewire_remote: server uses protocol version %d while the client is using protocol version %d", response.protocol_version, GSR_DBUS_PROTOCOL_VERSION);
+        return false;
+    }
+
+    if(response.type == GSR_DBUS_MESSAGE_RESP_ERROR) {
+        fprintf(stderr, "gsr error: gsr_dbus_client_screencast_open_pipewire_remote: server return error: %s (%d)\n", response.error.message, (int)response.error.error_code);
+        return false;
+    }
+
+    if(response.type != GSR_DBUS_MESSAGE_RESP_OPEN_PIPEWIRE_REMOTE) {
+        fprintf(stderr, "gsr error: gsr_dbus_client_screencast_open_pipewire_remote: received incorrect response type. Expected %d got %d\n", GSR_DBUS_MESSAGE_RESP_OPEN_PIPEWIRE_REMOTE, response.type);
+        return false;
+    }
+
+    struct cmsghdr *cmsg = CMSG_FIRSTHDR(&message);
+    if(!cmsg || cmsg->cmsg_type != SCM_RIGHTS) {
+        fprintf(stderr, "gsr error: gsr_dbus_client_screencast_open_pipewire_remote: returned message data is missing file descriptor\n");
+        return false;
+    }
+
+    memcpy(pipewire_fd, CMSG_DATA(cmsg), sizeof(*pipewire_fd));
+    return true;
+}
+
+const char* gsr_dbus_client_screencast_get_restore_token(gsr_dbus_client *self) {
+    return self->screencast_restore_token;
+}

dbus/client/dbus_client.h

@@ -0,0 +1,36 @@
+#ifndef GSR_DBUS_CLIENT_H
+#define GSR_DBUS_CLIENT_H
+
+/*
+    Using a client-server architecture is needed for dbus because cap_sys_nice doesn't work with desktop portal.
+    The main binary has cap_sys_nice and we launch a new child-process without it which uses uses desktop portal.
+*/
+
+#include "../portal.h"
+#include <stdbool.h>
+#include <stdint.h>
+#include <signal.h>
+
+typedef struct {
+    int socket_pair[2];
+    char *screencast_restore_token;
+    pid_t pid;
+} gsr_dbus_client;
+
+/* Blocking. TODO: Make non-blocking */
+bool gsr_dbus_client_init(gsr_dbus_client *self, const char *screencast_restore_token);
+void gsr_dbus_client_deinit(gsr_dbus_client *self);
+
+/* The follow functions should be called in order to setup ScreenCast properly */
+/* These functions that return an int return the response status code */
+int gsr_dbus_client_screencast_create_session(gsr_dbus_client *self, char *session_handle, size_t session_handle_size);
+/*
+    |capture_type| is a bitmask of gsr_portal_capture_type values. gsr_portal_capture_type values that are not supported by the desktop portal will be ignored.
+    |gsr_portal_cursor_mode| is a bitmask of gsr_portal_cursor_mode values. gsr_portal_cursor_mode values that are not supported will be ignored.
+*/
+int gsr_dbus_client_screencast_select_sources(gsr_dbus_client *self, const char *session_handle, uint32_t capture_type, uint32_t cursor_mode);
+int gsr_dbus_client_screencast_start(gsr_dbus_client *self, const char *session_handle, uint32_t *pipewire_node);
+bool gsr_dbus_client_screencast_open_pipewire_remote(gsr_dbus_client *self, const char *session_handle, int *pipewire_fd);
+const char* gsr_dbus_client_screencast_get_restore_token(gsr_dbus_client *self);
+
+#endif /* GSR_DBUS_CLIENT_H */

dbus/dbus_impl.c

@@ -1,5 +1,6 @@
-#include "../include/dbus.h"
-#include "../include/utils.h"
+#include "dbus_impl.h"
+
+#include <sys/random.h>
 
 #include <stdio.h>
 #include <string.h>
@@ -28,6 +29,25 @@ typedef struct {
     };
 } dict_entry;
 
+static bool generate_random_characters(char *buffer, int buffer_size, const char *alphabet, size_t alphabet_size) {
+    /* TODO: Use other functions on other platforms than linux */
+    if(getrandom(buffer, buffer_size, 0) < buffer_size) {
+        fprintf(stderr, "Failed to get random bytes, error: %s\n", strerror(errno));
+        return false;
+    }
+
+    for(int i = 0; i < buffer_size; ++i) {
+        unsigned char c = *(unsigned char*)&buffer[i];
+        buffer[i] = alphabet[c % alphabet_size];
+    }
+
+    return true;
+}
+
+static bool generate_random_characters_standard_alphabet(char *buffer, int buffer_size) {
+    return generate_random_characters(buffer, buffer_size, "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789", 62);
+}
+
 static const char* dict_value_type_to_string(dict_value_type type) {
     switch(type) {
         case DICT_TYPE_STRING: return "string";

dbus/dbus_impl.h

@@ -1,6 +1,7 @@
 #ifndef GSR_DBUS_H
 #define GSR_DBUS_H
 
+#include "portal.h"
 #include <stdbool.h>
 #include <stdint.h>
 #include <dbus/dbus.h>
@@ -17,19 +18,6 @@ typedef struct {
     char *screencast_restore_token;
 } gsr_dbus;
 
-typedef enum {
-    GSR_PORTAL_CAPTURE_TYPE_MONITOR = 1 << 0,
-    GSR_PORTAL_CAPTURE_TYPE_WINDOW  = 1 << 1,
-    GSR_PORTAL_CAPTURE_TYPE_VIRTUAL = 1 << 2,
-    GSR_PORTAL_CAPTURE_TYPE_ALL = GSR_PORTAL_CAPTURE_TYPE_MONITOR | GSR_PORTAL_CAPTURE_TYPE_WINDOW | GSR_PORTAL_CAPTURE_TYPE_VIRTUAL
-} gsr_portal_capture_type;
-
-typedef enum {
-    GSR_PORTAL_CURSOR_MODE_HIDDEN   = 1 << 0,
-    GSR_PORTAL_CURSOR_MODE_EMBEDDED = 1 << 1,
-    GSR_PORTAL_CURSOR_MODE_METADATA = 1 << 2
-} gsr_portal_cursor_mode;
-
 /* Blocking. TODO: Make non-blocking */
 bool gsr_dbus_init(gsr_dbus *self, const char *screencast_restore_token);
 void gsr_dbus_deinit(gsr_dbus *self);

dbus/portal.h

@@ -0,0 +1,17 @@
+#ifndef GSR_PORTAL_H
+#define GSR_PORTAL_H
+
+typedef enum {
+    GSR_PORTAL_CAPTURE_TYPE_MONITOR = 1 << 0,
+    GSR_PORTAL_CAPTURE_TYPE_WINDOW  = 1 << 1,
+    GSR_PORTAL_CAPTURE_TYPE_VIRTUAL = 1 << 2,
+    GSR_PORTAL_CAPTURE_TYPE_ALL = GSR_PORTAL_CAPTURE_TYPE_MONITOR | GSR_PORTAL_CAPTURE_TYPE_WINDOW | GSR_PORTAL_CAPTURE_TYPE_VIRTUAL
+} gsr_portal_capture_type;
+
+typedef enum {
+    GSR_PORTAL_CURSOR_MODE_HIDDEN   = 1 << 0,
+    GSR_PORTAL_CURSOR_MODE_EMBEDDED = 1 << 1,
+    GSR_PORTAL_CURSOR_MODE_METADATA = 1 << 2
+} gsr_portal_cursor_mode;
+
+#endif /* GSR_PORTAL_H */

dbus/protocol.h

@@ -0,0 +1,86 @@
+#ifndef GSR_DBUS_PROTOCOL_H
+#define GSR_DBUS_PROTOCOL_H
+
+#include <stdint.h>
+
+#define GSR_DBUS_PROTOCOL_VERSION 1
+
+typedef enum {
+    GSR_DBUS_MESSAGE_REQ_CREATE_SESSION,
+    GSR_DBUS_MESSAGE_REQ_SELECT_SOURCES,
+    GSR_DBUS_MESSAGE_REQ_START,
+    GSR_DBUS_MESSAGE_REQ_OPEN_PIPEWIRE_REMOTE
+} gsr_dbus_message_req_type;
+
+typedef struct {
+
+} gsr_dbus_message_req_create_session;
+
+typedef struct {
+    char session_handle[128];
+    uint32_t capture_type;
+    uint32_t cursor_mode;
+} gsr_dbus_message_req_select_sources;
+
+typedef struct {
+    char session_handle[128];
+} gsr_dbus_message_req_start;
+
+typedef struct {
+    char session_handle[128];
+} gsr_dbus_message_req_open_pipewire_remote;
+
+typedef struct {
+    uint8_t protocol_version;
+    gsr_dbus_message_req_type type;
+    union {
+        gsr_dbus_message_req_create_session create_session;
+        gsr_dbus_message_req_select_sources select_sources;
+        gsr_dbus_message_req_start start;
+        gsr_dbus_message_req_open_pipewire_remote open_pipewire_remote;
+    };
+} gsr_dbus_request_message;
+
+typedef enum {
+    GSR_DBUS_MESSAGE_RESP_ERROR,
+    GSR_DBUS_MESSAGE_RESP_CREATE_SESSION,
+    GSR_DBUS_MESSAGE_RESP_SELECT_SOURCES,
+    GSR_DBUS_MESSAGE_RESP_START,
+    GSR_DBUS_MESSAGE_RESP_OPEN_PIPEWIRE_REMOTE
+} gsr_dbus_message_resp_type;
+
+typedef struct {
+    uint32_t error_code;
+    char message[128];
+} gsr_dbus_message_resp_error;
+
+typedef struct {
+    char session_handle[128];
+} gsr_dbus_message_resp_create_session;
+
+typedef struct {
+    
+} gsr_dbus_message_resp_select_sources;
+
+typedef struct {
+    char restore_token[128];
+    uint32_t pipewire_node;
+} gsr_dbus_message_resp_start;
+
+typedef struct {
+    
+} gsr_dbus_message_resp_open_pipewire_remote;
+
+typedef struct {
+    uint8_t protocol_version;
+    gsr_dbus_message_resp_type type;
+    union {
+        gsr_dbus_message_resp_error error;
+        gsr_dbus_message_resp_create_session create_session;
+        gsr_dbus_message_resp_select_sources select_sources;
+        gsr_dbus_message_resp_start start;
+        gsr_dbus_message_resp_open_pipewire_remote open_pipewire_remote;
+    };
+} gsr_dbus_response_message;
+
+#endif /* GSR_DBUS_PROTOCOL_H */

dbus/server/dbus_server.c

@@ -0,0 +1,175 @@
+#include "../dbus_impl.h"
+#include "../protocol.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <unistd.h>
+#include <sys/socket.h>
+
+/* TODO: Error check write/read */
+
+static int handle_create_session(gsr_dbus *dbus, int rpc_fd, const gsr_dbus_message_req_create_session *create_session) {
+    (void)create_session;
+    char *session_handle = NULL;
+    const int status = gsr_dbus_screencast_create_session(dbus, &session_handle);
+    if(status == 0) {
+        gsr_dbus_response_message response = {
+            .protocol_version = GSR_DBUS_PROTOCOL_VERSION,
+            .type = GSR_DBUS_MESSAGE_RESP_CREATE_SESSION,
+            .create_session = (gsr_dbus_message_resp_create_session) {}
+        };
+        snprintf(response.create_session.session_handle, sizeof(response.create_session.session_handle), "%s", session_handle);
+        free(session_handle);
+        write(rpc_fd, &response, sizeof(response));
+    }
+    return status;
+}
+
+static int handle_select_sources(gsr_dbus *dbus, int rpc_fd, const gsr_dbus_message_req_select_sources *select_sources) {
+    const int status = gsr_dbus_screencast_select_sources(dbus, select_sources->session_handle, select_sources->capture_type, select_sources->cursor_mode);
+    if(status == 0) {
+        gsr_dbus_response_message response = {
+            .protocol_version = GSR_DBUS_PROTOCOL_VERSION,
+            .type = GSR_DBUS_MESSAGE_RESP_SELECT_SOURCES,
+            .select_sources = (gsr_dbus_message_resp_select_sources) {}
+        };
+        write(rpc_fd, &response, sizeof(response));
+    }
+    return status;
+}
+
+static int handle_start(gsr_dbus *dbus, int rpc_fd, const gsr_dbus_message_req_start *start) {
+    uint32_t pipewire_node = 0;
+    const int status = gsr_dbus_screencast_start(dbus, start->session_handle, &pipewire_node);
+    if(status == 0) {
+        const char *screencast_restore_token = gsr_dbus_screencast_get_restore_token(dbus);
+        gsr_dbus_response_message response = {
+            .protocol_version = GSR_DBUS_PROTOCOL_VERSION,
+            .type = GSR_DBUS_MESSAGE_RESP_START,
+            .start = (gsr_dbus_message_resp_start) {
+                .pipewire_node = pipewire_node
+            }
+        };
+        snprintf(response.start.restore_token, sizeof(response.start.restore_token), "%s", screencast_restore_token ? screencast_restore_token : "");
+        write(rpc_fd, &response, sizeof(response));
+    }
+    return status;
+}
+
+static bool handle_open_pipewire_remote(gsr_dbus *dbus, int rpc_fd, const gsr_dbus_message_req_open_pipewire_remote *open_pipewire_remote) {
+    int pipewire_fd = 0;
+    const bool success = gsr_dbus_screencast_open_pipewire_remote(dbus, open_pipewire_remote->session_handle, &pipewire_fd);
+    if(success) {
+        gsr_dbus_response_message response = {
+            .protocol_version = GSR_DBUS_PROTOCOL_VERSION,
+            .type = GSR_DBUS_MESSAGE_RESP_OPEN_PIPEWIRE_REMOTE,
+            .open_pipewire_remote = (gsr_dbus_message_resp_open_pipewire_remote) {}
+        };
+
+        struct iovec iov = {
+            .iov_base = &response,
+            .iov_len = sizeof(response)
+        };
+
+        char msg_control[CMSG_SPACE(sizeof(int))];
+
+        struct msghdr message = {
+            .msg_iov = &iov,
+            .msg_iovlen = 1,
+            .msg_control = msg_control,
+            .msg_controllen = sizeof(msg_control)
+        };
+
+        struct cmsghdr *cmsg = CMSG_FIRSTHDR(&message);
+        cmsg->cmsg_level = SOL_SOCKET;
+        cmsg->cmsg_type = SCM_RIGHTS;
+        cmsg->cmsg_len = CMSG_LEN(sizeof(int));
+        int *fds = (int*)CMSG_DATA(cmsg);
+        fds[0] = pipewire_fd;
+        message.msg_controllen = cmsg->cmsg_len;
+        sendmsg(rpc_fd, &message, 0);
+    }
+    return success;
+}
+
+int main(int argc, char **argv) {
+    if(argc != 3) {
+        fprintf(stderr, "usage: gsr-dbus-server <rpc-fd> <screencast-restore-token>\n");
+        return 1;
+    }
+
+    const char *rpc_fd_str = argv[1];
+    const char *screencast_restore_token = argv[2];
+
+    int rpc_fd = -1;
+    if(sscanf(rpc_fd_str, "%d", &rpc_fd) != 1) {
+        fprintf(stderr, "gsr-dbus-server error: rpc-fd is not a number: %s\n", rpc_fd_str);
+        return 1;
+    }
+
+    if(screencast_restore_token[0] == '\0')
+        screencast_restore_token = NULL;
+
+    gsr_dbus dbus;
+    if(!gsr_dbus_init(&dbus, screencast_restore_token))
+        return 1;
+
+    /* Tell client we have started up */
+    write(rpc_fd, "S", 1);
+
+    gsr_dbus_request_message request;
+    for(;;) {
+        read(rpc_fd, &request, sizeof(request));
+
+        if(request.protocol_version != GSR_DBUS_PROTOCOL_VERSION) {
+            gsr_dbus_response_message response = {
+                .protocol_version = GSR_DBUS_PROTOCOL_VERSION,
+                .type = GSR_DBUS_MESSAGE_RESP_ERROR,
+                .error = (gsr_dbus_message_resp_error) {
+                    .error_code = 1
+                }
+            };
+            snprintf(response.error.message, sizeof(response.error.message), "Client uses protocol version %d while the server is using protocol version %d", request.protocol_version, GSR_DBUS_PROTOCOL_VERSION);
+            fprintf(stderr, "gsr-dbus-server error: %s\n", response.error.message);
+            write(rpc_fd, &response, sizeof(response));
+            continue;
+        }
+
+        int status = 0;
+        switch(request.type) {
+            case GSR_DBUS_MESSAGE_REQ_CREATE_SESSION: {
+                status = handle_create_session(&dbus, rpc_fd, &request.create_session);
+                break;
+            }
+            case GSR_DBUS_MESSAGE_REQ_SELECT_SOURCES: {
+                status = handle_select_sources(&dbus, rpc_fd, &request.select_sources);
+                break;
+            }
+            case GSR_DBUS_MESSAGE_REQ_START: {
+                status = handle_start(&dbus, rpc_fd, &request.start);
+                break;
+            }
+            case GSR_DBUS_MESSAGE_REQ_OPEN_PIPEWIRE_REMOTE: {
+                if(!handle_open_pipewire_remote(&dbus, rpc_fd, &request.open_pipewire_remote))
+                    status = -1;
+                break;
+            }
+        }
+
+        if(status != 0) {
+            gsr_dbus_response_message response = {
+                .protocol_version = GSR_DBUS_PROTOCOL_VERSION,
+                .type = GSR_DBUS_MESSAGE_RESP_ERROR,
+                .error = (gsr_dbus_message_resp_error) {
+                    .error_code = status
+                }
+            };
+            snprintf(response.error.message, sizeof(response.error.message), "%s", "Failed to handle request");
+            write(rpc_fd, &response, sizeof(response));
+        }
+    }
+
+    gsr_dbus_deinit(&dbus);
+    return 0;
+}

extra/meson_post_install.sh

@@ -4,14 +4,7 @@
 /usr/sbin/setcap cap_sys_admin+ep ${MESON_INSTALL_DESTDIR_PREFIX}/bin/gsr-kms-server \
     || echo "\n!!! Please re-run install as root\n"
 
-# Cant do this because it breaks desktop portal (create session)!!!.
-# For some reason the desktop portal tries to access /proc/gpu-screen-recorder-pid/root from the portal process
-# which doesn't work because for some reason CAP_SYS_NICE on a program makes /proc/self/root not readable by other processes.
-# The reason portal reads that file might be because portal seems to have a security feature where its able to identify the
-# process and if the session token is stolen by another application then it will ignore the session token as it wasn't that
-# application that created the session token.
-# ---
 # This is needed (for EGL_CONTEXT_PRIORITY_HIGH_IMG) to allow gpu screen recorder to run faster than the heaviest application on AMD.
 # For example when trying to record a game at 60 fps and the game drops to 45 fps in some place that would also make gpu screen recorder
-# drop to 45 fps unless this setcap is used.
-#/usr/sbin/setcap cap_sys_nice+ep ${MESON_INSTALL_DESTDIR_PREFIX}/bin/gpu-screen-recorder
+# drop to 45 fps unless this setcap is used. Recording would also drop to below 60 fps in some games even though they run above 60 fps.
+/usr/sbin/setcap cap_sys_nice+ep ${MESON_INSTALL_DESTDIR_PREFIX}/bin/gpu-screen-recorder

kms/client/kms_client.c

@@ -387,6 +387,7 @@ void cleanup_socket(gsr_kms_client *self, bool kill_server) {
 
     if(kill_server && self->kms_server_pid > 0) {
         kill(self->kms_server_pid, SIGKILL);
+        // TODO:
         //int status;
         //waitpid(self->kms_server_pid, &status, 0);
         self->kms_server_pid = -1;

kms/server/kms_server.c

@@ -8,6 +8,7 @@
 #include <string.h>
 #include <errno.h>
 #include <stdlib.h>
+#include <locale.h>
 
 #include <unistd.h>
 #include <limits.h>
@@ -434,6 +435,8 @@ static double clock_get_monotonic_seconds(void) {
 }
 
 int main(int argc, char **argv) {
+    setlocale(LC_ALL, "C"); // Sigh... stupid C
+
     int res = 0;
     int socket_fd = 0;
     gsr_drm drm;

meson.build

@@ -76,10 +76,9 @@ uses_pipewire = false
 if get_option('portal') == true
     src += [
         'src/capture/portal.c',
-        'src/dbus.c',
+        'dbus/client/dbus_client.c',
         'src/pipewire_video.c',
     ]
-    dep += dependency('dbus-1')
     add_project_arguments('-DGSR_PORTAL', language : ['c', 'cpp'])
     uses_pipewire = true
 endif
@@ -104,6 +103,10 @@ add_project_arguments('-DGSR_VERSION="' + meson.project_version() + '"', languag
 executable('gsr-kms-server', 'kms/server/kms_server.c', dependencies : dependency('libdrm'), c_args : '-fstack-protector-all', install : true)
 executable('gpu-screen-recorder', src, dependencies : dep, install : true)
 
+if get_option('portal') == true
+    executable('gsr-dbus-server', ['dbus/server/dbus_server.c', 'dbus/dbus_impl.c'], dependencies : dependency('dbus-1'), install : true)
+endif
+
 if get_option('systemd') == true
     install_data(files('extra/gpu-screen-recorder.service'), install_dir : 'lib/systemd/user')
 endif

meson_options.txt

@@ -1,5 +1,5 @@
 option('systemd', type : 'boolean', value : true, description : 'Install systemd service file')
-option('capabilities', type : 'boolean', value : true, description : 'Set binary admin capability on gsr-kms-server binary to remove password prompt when recording monitor (without desktop portal option) on amd/intel or nvidia wayland')
+option('capabilities', type : 'boolean', value : true, description : 'Set binary admin capability on gsr-kms-server binary to remove password prompt when recording monitor (without desktop portal option) on amd/intel or nvidia wayland. Also sets nice capability on gpu-screen-recorder to allow it to run as a high priority graphics process for better performance')
 option('nvidia_suspend_fix', type : 'boolean', value : true, description : 'Install nvidia modprobe config file to tell nvidia driver to preserve video memory on suspend. This is a workaround for an nvidia driver bug that breaks cuda (and gpu screen recorder) on suspend')
 option('portal', type : 'boolean', value : true, description : 'Build with support for xdg desktop portal ScreenCast capture (wayland only) (-w portal option). Requires pipewire')
 option('app_audio', type : 'boolean', value : true, description : 'Build with support for recording a single audio source (-a app: option). Requires pipewire')

src/capture/portal.c

@@ -2,7 +2,7 @@
 #include "../../include/color_conversion.h"
 #include "../../include/egl.h"
 #include "../../include/utils.h"
-#include "../../include/dbus.h"
+#include "../../dbus/client/dbus_client.h"
 #include "../../include/pipewire_video.h"
 
 #include <stdlib.h>
@@ -16,8 +16,8 @@ typedef struct {
 
     gsr_texture_map texture_map;
 
-    gsr_dbus dbus;
-    char *session_handle;
+    gsr_dbus_client dbus_client;
+    char session_handle[128];
 
     gsr_pipewire_video pipewire;
     vec2i capture_size;
@@ -52,15 +52,8 @@ static void gsr_capture_portal_stop(gsr_capture_portal *self) {
     }
 
     gsr_capture_portal_cleanup_plane_fds(self);
-
     gsr_pipewire_video_deinit(&self->pipewire);
-
-    if(self->session_handle) {
-        free(self->session_handle);
-        self->session_handle = NULL;
-    }
-
-    gsr_dbus_deinit(&self->dbus);
+    gsr_dbus_client_deinit(&self->dbus_client);
 }
 
 static void gsr_capture_portal_create_input_textures(gsr_capture_portal *self) {
@@ -195,36 +188,36 @@ static int gsr_capture_portal_setup_dbus(gsr_capture_portal *self, int *pipewire
     if(self->params.restore_portal_session)
         gsr_capture_portal_get_restore_token_from_cache(restore_token, sizeof(restore_token), self->params.portal_session_token_filepath);
 
-    if(!gsr_dbus_init(&self->dbus, restore_token))
+    if(!gsr_dbus_client_init(&self->dbus_client, restore_token))
         return -1;
 
     fprintf(stderr, "gsr info: gsr_capture_portal_setup_dbus: CreateSession\n");
-    response_status = gsr_dbus_screencast_create_session(&self->dbus, &self->session_handle);
+    response_status = gsr_dbus_client_screencast_create_session(&self->dbus_client, self->session_handle, sizeof(self->session_handle));
     if(response_status != 0) {
         fprintf(stderr, "gsr error: gsr_capture_portal_setup_dbus: CreateSession failed\n");
         return response_status;
     }
 
     fprintf(stderr, "gsr info: gsr_capture_portal_setup_dbus: SelectSources\n");
-    response_status = gsr_dbus_screencast_select_sources(&self->dbus, self->session_handle, GSR_PORTAL_CAPTURE_TYPE_ALL, self->params.record_cursor ? GSR_PORTAL_CURSOR_MODE_EMBEDDED : GSR_PORTAL_CURSOR_MODE_HIDDEN);
+    response_status = gsr_dbus_client_screencast_select_sources(&self->dbus_client, self->session_handle, GSR_PORTAL_CAPTURE_TYPE_ALL, self->params.record_cursor ? GSR_PORTAL_CURSOR_MODE_EMBEDDED : GSR_PORTAL_CURSOR_MODE_HIDDEN);
     if(response_status != 0) {
         fprintf(stderr, "gsr error: gsr_capture_portal_setup_dbus: SelectSources failed\n");
         return response_status;
     }
 
     fprintf(stderr, "gsr info: gsr_capture_portal_setup_dbus: Start\n");
-    response_status = gsr_dbus_screencast_start(&self->dbus, self->session_handle, pipewire_node);
+    response_status = gsr_dbus_client_screencast_start(&self->dbus_client, self->session_handle, pipewire_node);
     if(response_status != 0) {
         fprintf(stderr, "gsr error: gsr_capture_portal_setup_dbus: Start failed\n");
         return response_status;
     }
 
-    const char *screencast_restore_token = gsr_dbus_screencast_get_restore_token(&self->dbus);
+    const char *screencast_restore_token = gsr_dbus_client_screencast_get_restore_token(&self->dbus_client);
     if(screencast_restore_token)
         gsr_capture_portal_save_restore_token(screencast_restore_token, self->params.portal_session_token_filepath);
 
     fprintf(stderr, "gsr info: gsr_capture_portal_setup_dbus: OpenPipeWireRemote\n");
-    if(!gsr_dbus_screencast_open_pipewire_remote(&self->dbus, self->session_handle, pipewire_fd)) {
+    if(!gsr_dbus_client_screencast_open_pipewire_remote(&self->dbus_client, self->session_handle, pipewire_fd)) {
         fprintf(stderr, "gsr error: gsr_capture_portal_setup_dbus: OpenPipeWireRemote failed\n");
         return -1;
     }

src/egl.c

@@ -60,7 +60,7 @@ static bool gsr_egl_create_window(gsr_egl *self) {
 
     const int32_t ctxattr[] = {
         EGL_CONTEXT_CLIENT_VERSION, 2,
-        //EGL_CONTEXT_PRIORITY_LEVEL_IMG, EGL_CONTEXT_PRIORITY_HIGH_IMG, /* requires cap_sys_nice, ignored otherwise */
+        EGL_CONTEXT_PRIORITY_LEVEL_IMG, EGL_CONTEXT_PRIORITY_HIGH_IMG, /* requires cap_sys_nice, ignored otherwise */
         EGL_NONE, EGL_NONE
     };
 

src/main.cpp

@@ -5,7 +5,7 @@ extern "C" {
 #include "../include/capture/kms.h"
 #ifdef GSR_PORTAL
 #include "../include/capture/portal.h"
-#include "../include/dbus.h"
+#include "../dbus/client/dbus_client.h"
 #endif
 #ifdef GSR_APP_AUDIO
 #include "../include/pipewire_audio.h"
@@ -1843,16 +1843,15 @@ static void list_supported_capture_options(const gsr_window *window, const char
     if(!wayland)
         return;
 
-    gsr_dbus dbus;
-    if(!gsr_dbus_init(&dbus, NULL))
+    gsr_dbus_client dbus_client;
+    if(!gsr_dbus_client_init(&dbus_client, NULL))
         return;
 
-    char *session_handle = NULL;
-    if(gsr_dbus_screencast_create_session(&dbus, &session_handle) == 0) {
-        free(session_handle);
+    char session_handle[128];
+    if(gsr_dbus_client_screencast_create_session(&dbus_client, session_handle, sizeof(session_handle)) == 0)
         puts("portal");
-    }
-    gsr_dbus_deinit(&dbus);
+
+    gsr_dbus_client_deinit(&dbus_client);
 #endif
 }