gpu-screen-recorder/kms/server/kms_server.c

245 lines
8.9 KiB
C

#include "../kms_shared.h"
#include <asm-generic/socket.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <xf86drm.h>
#include <xf86drmMode.h>
#define DRM_CLIENT_CAP_UNIVERSAL_PLANES 2
static int max_int(int a, int b) {
return a > b ? a : b;
}
static int send_msg_to_client(int client_fd, gsr_kms_response *response, int *fds, int num_fds) {
struct iovec iov;
iov.iov_base = response;
iov.iov_len = sizeof(*response);
struct msghdr response_message = {0};
response_message.msg_iov = &iov;
response_message.msg_iovlen = 1;
char cmsgbuf[CMSG_SPACE(sizeof(int)) * max_int(1, num_fds)];
memset(cmsgbuf, 0, sizeof(cmsgbuf));
if(num_fds > 0) {
response_message.msg_control = cmsgbuf;
response_message.msg_controllen = sizeof(cmsgbuf);
int total_msg_len = 0;
struct cmsghdr *cmsg = NULL;
for(int i = 0; i < num_fds; ++i) {
if(i == 0)
cmsg = CMSG_FIRSTHDR(&response_message);
else
cmsg = CMSG_NXTHDR(&response_message, cmsg);
cmsg->cmsg_level = SOL_SOCKET;
cmsg->cmsg_type = SCM_RIGHTS;
cmsg->cmsg_len = CMSG_LEN(sizeof(int));
memcpy(CMSG_DATA(cmsg), &fds[i], sizeof(int));
total_msg_len += cmsg->cmsg_len;
}
response_message.msg_controllen = total_msg_len;
}
return sendmsg(client_fd, &response_message, 0);
}
static int get_kms(const char *card_path, gsr_kms_response *response) {
response->result = KMS_RESULT_OK;
response->data.fd.fd = 0;
response->data.fd.width = 0;
response->data.fd.height = 0;
const int drmfd = open(card_path, O_RDONLY);
if (drmfd < 0) {
response->result = KMS_RESULT_FAILED_TO_OPEN_CARD;
snprintf(response->data.err_msg, sizeof(response->data.err_msg), "failed to open %s, error: %s", card_path, strerror(errno));
return -1;
}
if (0 != drmSetClientCap(drmfd, DRM_CLIENT_CAP_UNIVERSAL_PLANES, 1)) {
response->result = KMS_RESULT_INSUFFICIENT_PERMISSIONS;
snprintf(response->data.err_msg, sizeof(response->data.err_msg), "drmSetClientCap failed, error: %s", strerror(errno));
close(drmfd);
return -1;
}
drmModePlaneResPtr planes = drmModeGetPlaneResources(drmfd);
if (!planes) {
response->result = KMS_RESULT_FAILED_TO_GET_KMS;
snprintf(response->data.err_msg, sizeof(response->data.err_msg), "failed to access planes, error: %s", strerror(errno));
close(drmfd);
return -1;
}
fprintf(stderr, "DRM planes %d:\n", planes->count_planes);
for (uint32_t i = 0; i < planes->count_planes; ++i) {
drmModePlanePtr plane = drmModeGetPlane(drmfd, planes->planes[i]);
if (!plane) {
fprintf(stderr, "Cannot get drmModePlanePtr for plane %#x: %s (%d)\n", planes->planes[i], strerror(errno), errno);
continue;
}
fprintf(stderr, "\t%d: fb_id=%#x\n", i, plane->fb_id);
if (!plane->fb_id)
goto plane_continue;
drmModeFB2Ptr drmfb = drmModeGetFB2(drmfd, plane->fb_id);
if (!drmfb) {
fprintf(stderr, "Cannot get drmModeFBPtr for fb %#x: %s (%d)\n", plane->fb_id, strerror(errno), errno);
} else {
if (!drmfb->handles[0]) {
fprintf(stderr, "\t\tFB handle for fb %#x is NULL\n", plane->fb_id);
fprintf(stderr, "\t\tPossible reason: not permitted to get FB handles. Do `sudo setcap cap_sys_admin+ep`\n");
} else {
int fb_fd = -1;
const int ret = drmPrimeHandleToFD(drmfd, drmfb->handles[0], 0, &fb_fd);
if (ret != 0 || fb_fd == -1) {
fprintf(stderr, "Cannot get fd for fb %#x handle %#x: %s (%d)\n", plane->fb_id, drmfb->handles[0], strerror(errno), errno);
} else if(drmfb->width * drmfb->height > response->data.fd.width * response->data.fd.height) {
if(response->data.fd.fd != 0) {
close(response->data.fd.fd);
response->data.fd.fd = 0;
}
response->data.fd.fd = fb_fd;
response->data.fd.width = drmfb->width;
response->data.fd.height = drmfb->height;
response->data.fd.pitch = drmfb->pitches[0];
response->data.fd.offset = drmfb->offsets[0];
response->data.fd.pixel_format = drmfb->pixel_format;
response->data.fd.modifier = drmfb->modifier;
fprintf(stderr, "kms width: %u, height: %u, pixel format: %u, modifier: %lu\n", response->data.fd.width, response->data.fd.height, response->data.fd.pixel_format, response->data.fd.modifier);
} else {
close(fb_fd);
}
}
drmModeFreeFB2(drmfb);
}
plane_continue:
drmModeFreePlane(plane);
}
drmModeFreePlaneResources(planes);
close(drmfd);
if(response->data.fd.fd == 0) {
response->result = KMS_RESULT_NO_KMS_AVAILABLE;
snprintf(response->data.err_msg, sizeof(response->data.err_msg), "no kms found");
return -1;
}
return 0;
}
int main(int argc, char **argv) {
if(argc != 2) {
fprintf(stderr, "usage: kms_server <domain_socket_path>\n");
return 1;
}
const char *domain_socket_path = argv[1];
int socket_fd = socket(AF_UNIX, SOCK_STREAM, 0);
if(socket_fd == -1) {
fprintf(stderr, "kms server error: failed to create socket, error: %s\n", strerror(errno));
return 2;
}
fprintf(stderr, "kms server info: connecting to the server\n");
for(;;) {
struct sockaddr_un remote_addr = {0};
remote_addr.sun_family = AF_UNIX;
strncpy(remote_addr.sun_path, domain_socket_path, sizeof(remote_addr.sun_path));
// TODO: Check if parent disconnected
if(connect(socket_fd, (struct sockaddr*)&remote_addr, sizeof(remote_addr.sun_family) + strlen(remote_addr.sun_path)) == -1) {
if(errno == ECONNREFUSED || errno == ENOENT)
continue; // Host not ready yet? TODO: sleep
if(errno == EISCONN) // TODO?
break;
fprintf(stderr, "kms server error: connect failed, error: %s (%d)\n", strerror(errno), errno);
return 2;
}
}
fprintf(stderr, "kms server info: connected to the server\n");
int res = 0;
for(;;) {
gsr_kms_request request;
struct iovec iov;
iov.iov_base = &request;
iov.iov_len = sizeof(request);
struct msghdr request_message = {0};
request_message.msg_iov = &iov;
request_message.msg_iovlen = 1;
const int recv_res = recvmsg(socket_fd, &request_message, MSG_WAITALL);
if(recv_res == 0) {
fprintf(stderr, "kms server info: kms client shutdown, shutting down the server\n");
res = 3;
goto done;
} else if(recv_res == -1) {
const int err = errno;
fprintf(stderr, "kms server error: failed to read all data in client request (error: %s), ignoring\n", strerror(err));
if(err == EBADF) {
fprintf(stderr, "kms server error: invalid client fd, shutting down the server\n");
res = 3;
goto done;
}
continue;
}
request.data.card_path[254] = '\0';
switch(request.type) {
case KMS_REQUEST_TYPE_GET_KMS: {
gsr_kms_response response;
int kms_fd = 0;
if (get_kms(request.data.card_path, &response) == 0) {
kms_fd = response.data.fd.fd;
}
if(send_msg_to_client(socket_fd, &response, &kms_fd, kms_fd == 0 ? 0 : 1) == -1) {
fprintf(stderr, "kms server error: failed to respond to client KMS_REQUEST_TYPE_GET_KMS request\n");
if(kms_fd != 0)
close(kms_fd);
break;
}
if(kms_fd != 0)
close(kms_fd);
break;
}
default: {
gsr_kms_response response;
response.result = KMS_RESULT_INVALID_REQUEST;
snprintf(response.data.err_msg, sizeof(response.data.err_msg), "invalid request type %d, expected %d (%s)", request.type, KMS_REQUEST_TYPE_GET_KMS, "KMS_REQUEST_TYPE_GET_KMS");
fprintf(stderr, "%s\n", response.data.err_msg);
if(send_msg_to_client(socket_fd, &response, NULL, 0) == -1) {
fprintf(stderr, "kms server error: failed to respond to client request\n");
break;
}
break;
}
}
}
done:
close(socket_fd);
return res;
}