Attachment 129749 Details for Bug 99866 – Little test app implementing xrandr loop

Little test app implementing xrandr loop

reconnect_vga.c (text/plain), 6.53 KB, created by jorge_monteagudo on 2017-02-20 07:20:06 UTC

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Creator: jorge_monteagudo

Created: 2017-02-20 07:20:06 UTC

Size: 6.53 KB

patch

obsolete

>/*
> * Implements the loop checking when a new display is conected/disconnected
> * which was done in bash.
> *
> * # Loop forever looking for 'disconnect' to 'connect' transitions.
> * until [ -z 1 ]
> * do
> * 	sleep 3
> * 
> * 	# Get new state.
> * 	RES=`xrandr -q | grep "$SCREEN_TOP connected"`
> * 	if [ "$RES" != "" ]
> * 	then
> * 		NEW_STATE="connected"
> * 	else
> * 		NEW_STATE="disconnected"
> * 	fi
> * 
> * 	# Activate output when state change detected.
> * 	if( [ "$OLD_STATE" == "disconnected" ] && [ "$NEW_STATE" == "connected" ])
> * 	then
> * 		xrandr --output $SCREEN_TOP --auto --rotate normal --pos 0x0 --output $SCREEN_BOTTOM --auto --rotate normal --below $SCREEN_TOP
> * 	fi
> * 
> * 	# Save new state
> * 	OLD_STATE=$NEW_STATE
> * done
> * 
> */
>
>#include <stdio.h>
>#include <string.h>
>#include <stdarg.h>
>#include <stdlib.h>
>#include <signal.h>
>#include <unistd.h>
>#include <sys/wait.h>
>#include <fcntl.h>
>#include <X11/Xlib.h>
>#include <X11/extensions/Xrandr.h>
>
>#define OCNE(X) ((XRROutputChangeNotifyEvent*)X)
>#define BUFFER_SIZE 128
>
>#define SCREEN_TOP       0
>#define SCREEN_BOTTOM    1
>#define NUM_SCREENS      2
>
>// Flag to exit.
>static int done = 0;
>
>// Connections to check.
>static char *screens[NUM_SCREENS];
>
>// Connections state.
>static Connection curr_con_state[NUM_SCREENS];
>static Connection last_con_state[NUM_SCREENS];
>
>// Command to configure screens.
>static char *xrandr_cmd[15] = {
>    "/usr/bin/xrandr",
>    "--output",
>    NULL, //$SCREEN_TOP (2)
>    "--auto",
>    "--rotate",
>    "normal",
>    "--pos",
>    "0x0",
>    "--output",
>    NULL, //$SCREEN_BOTTOM (9)
>    "--auto",
>    "--rotate",
>    "normal",
>    "--below",
>    NULL, //$SCREEN_TOP (14)
>};
>
>
>void sigint_handler(int sig)
>{
>    printf( "Ctrl+C received, exiting...\n" );
>    done = 1;
>}
>
>
>void UpdateConnectionState(XRROutputInfo *info)
>{
>    int idx = -1;
>
>    // Find affected screen.
>    printf("output: %s ", info->name);
>    for (int i = 0; i < NUM_SCREENS; i++) {
>        if( strcmp(screens[i], info->name) == 0 ) {
>            idx = i;
>            break;
>        }
>    }
>    if (idx == -1) {
>        printf("Not handled!\n");
>        return;
>    }
>
>    switch (info->connection) {
>        case RR_Connected:
>            printf("connected\n");
>            curr_con_state[idx] = RR_Connected;
>            break;
>        case RR_Disconnected:
>            printf("disconnected\n");
>            curr_con_state[idx] = RR_Disconnected;
>            break;
>        default:
>            printf("unknown\n");
>            curr_con_state[idx] = RR_UnknownConnection;
>            break;
>    }
>}
>
>
>int main(int argc, char **argv)
>{
>    Display *dpy;
>    XRRScreenResources *resources;
>    int	screen;
>
>    // Initialize vars.
>    for (int i = 0; i < NUM_SCREENS; i++) {
>        screens[i] = NULL;
>        curr_con_state[i] = RR_UnknownConnection;
>        last_con_state[i] = RR_UnknownConnection;
>    }
>
>    // Check arguments.
>    if (argc != 3) {
>        fprintf(stderr, "Usage:\n\t%s <SCREEN_TOP> <SCREEN_BOTTOM>\n\n", argv[0]);
>        exit(EXIT_FAILURE);
>    }
>    screens[SCREEN_TOP] = argv[1];
>    screens[SCREEN_BOTTOM] = argv[2];
>
>    // Compose xrandr command.
>    xrandr_cmd[2] = screens[SCREEN_TOP];
>    xrandr_cmd[9] = screens[SCREEN_BOTTOM];
>    xrandr_cmd[14] = screens[SCREEN_TOP];
>
>    // Set CTRL+C signal handler.
>    signal(SIGINT, sigint_handler);
>
>    // Open display.
>    if ((dpy = XOpenDisplay(NULL)) == NULL) {
>        fprintf(stderr, "Cannot open display\n");
>        exit(EXIT_FAILURE);
>    }
>
>    while (done == 0) {
>
>        // Get info about available resources.
>        resources = XRRGetScreenResources(dpy, DefaultRootWindow(dpy));
>        if (resources == NULL) {
>            fprintf(stderr, "Could not get screen resources\n");
>            exit(EXIT_FAILURE);
>        }
>
>        // Get screen.
>        screen = DefaultScreen(dpy);
>        printf("Display width %d, height %d\n",
>               DisplayWidth(dpy, screen), DisplayHeight(dpy, screen));
>
>        // Update current state.
>        for (int o = 0; o < resources->noutput; o++) {
>            XRROutputInfo *info = XRRGetOutputInfo(dpy, resources, resources->outputs[o]);
>            if (info == NULL) {
>                fprintf(stderr, "could not get output 0x%lx information\n", resources->outputs[o]);
>                continue;
>            }
>
>            UpdateConnectionState(info);
>            XRRFreeOutputInfo(info);
>        }
>        printf("\n");
>
>        // Release resources.
>        XRRFreeScreenResources(resources);
>
>        // Check when TOP changes from disconnected to connected.
>        if( last_con_state[SCREEN_TOP] == RR_Disconnected && curr_con_state[SCREEN_TOP] == RR_Connected ) {
>            printf("Run xrandr command...\n");
>            if (fork() == 0) {
>                if (dpy)
>                    close(ConnectionNumber(dpy));
>                setsid();
>                execvp(xrandr_cmd[0], xrandr_cmd);
>            }
>        }
>
>        // Update state.
>        for (int i = 0; i < NUM_SCREENS; i++) {
>            last_con_state[i] = curr_con_state[i];
>        }
>
>#if 0
>    // Process XRandr events.
>    printf("1...\n");
>    XEvent ev;
>    char buf[BUFFER_SIZE];
>    XRRSelectInput(dpy, DefaultRootWindow(dpy), RROutputChangeNotifyMask);
>    printf("11...\n");
>    XSync(dpy, False);
>    printf("111...\n");
>    XSetIOErrorHandler((XIOErrorHandler) error_handler);
>    while (done == 0) {
>        printf("1111...\n");
>        if (!XNextEvent(dpy, &ev)) {
>            printf("New event received...\n");
>            XRROutputInfo *info = XRRGetOutputInfo(OCNE(&ev)->display, resources,
>                    OCNE(&ev)->output);
>            if (info == NULL) {
>                fprintf(stderr, "Could not get output info\n");
>                continue;
>            }
>
>            snprintf(buf, BUFFER_SIZE, "%s %s", info->name,
>                    con_actions[info->connection]);
>            printf("Event: %s %s\n", info->name,
>                    con_actions[info->connection]);
>            printf("Time: %lu\n", info->timestamp);
>            if (info->crtc == 0) {
>                printf("Size: %lumm x %lumm\n", info->mm_width, info->mm_height);
>            }
>            else {
>                printf("CRTC: %lu\n", info->crtc);
>                XRRCrtcInfo *crtc = XRRGetCrtcInfo(dpy, resources, info->crtc);
>                if (crtc != NULL) {
>                    printf("Size: %dx%d\n", crtc->width, crtc->height);
>                    XRRFreeCrtcInfo(crtc);
>                }
>            }
>/*
>*/
>            XRRFreeOutputInfo(info);
>        } else {
>            printf("Wait event...\n");
>        }
>    }
>#endif
>
>        sleep(3);
>    }
>
>    XCloseDisplay(dpy);
>
>    return EXIT_SUCCESS;
>}
>

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Attachments on bug 99866: 129748 | 129749 | 129750 | 129751 | 129788

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