1 files changed, 107 insertions, 0 deletions
diff --git a/tools/guest-diag/xgrab.c b/tools/guest-diag/xgrab.c
new file mode 100644
index 0000000..3f4ec76
--- /dev/null
+++ b/tools/guest-diag/xgrab.c
@@ -0,0 +1,107 @@
+// SPDX-License-Identifier: BSD-3-Clause
+// xgrab.c - capture the X screen (root window) into an append-only frame file.
+// Pure client-side XGetImage on a software X server (Xvfb): no GL, no driver,
+// no present-path hooks. Same record format as sdl_cap.c:
+//   [0]   8B "GZCAPV01" + zero pad to 4096
+//   [4096..] records: 4B "GZF2" | u32 w | u32 h | u32 stride | u32 bpp |
+//                     u64 ts_ns | u64 seq | stride*h bytes (top-down BGRA)
+// Trailing record seq=0xFFFFFFFFFFFFFFFF on clean stop.
+// Usage: xgrab <display> <out> <maxframes|0> <pace_us|0>
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+
+int main(int argc, char **argv)
+{
+    const char *dpy = argc > 1 ? argv[1] : ":1";
+    const char *out = argc > 2 ? argv[2] : "/dev/shm/gzframes.bin";
+    long maxf = argc > 3 ? atol(argv[3]) : 0;
+    long pace = argc > 4 ? atol(argv[4]) : 0;
+    Display *d;
+    Window root;
+    XWindowAttributes wa;
+    FILE *f;
+    char hdr[4096];
+    uint64_t seq = 0;
+
+    d = XOpenDisplay(dpy);
+    if (!d) {
+        fprintf(stderr, "xgrab: cannot open display %s\n", dpy);
+        return 1;
+    }
+    root = DefaultRootWindow(d);
+    if (!XGetWindowAttributes(d, root, &wa)) {
+        fprintf(stderr, "xgrab: no root attrs\n");
+        return 1;
+    }
+    fprintf(stderr, "xgrab: root %dx%d depth=%d\n", wa.width, wa.height,
+            wa.depth);
+    f = fopen(out, "wb");
+    if (!f) {
+        perror("xgrab: open out");
+        return 1;
+    }
+    memset(hdr, 0, sizeof(hdr));
+    memcpy(hdr, "GZCAPV01", 8);
+    fwrite(hdr, 1, sizeof(hdr), f);
+    fflush(f);
+
+    while (!maxf || (long)seq < maxf) {
+        XImage *im = XGetImage(d, root, 0, 0, wa.width, wa.height,
+                               AllPlanes, ZPixmap);
+        struct timespec ts;
+        uint64_t tns;
+        uint32_t rh[4];
+        char m[4] = { 'G', 'Z', 'F', '2' };
+        int y;
+
+        if (!im) {
+            usleep(10000);
+            continue;
+        }
+        if (im->bits_per_pixel != 32) {
+            fprintf(stderr, "xgrab: unexpected bpp %d\n",
+                    im->bits_per_pixel);
+            XDestroyImage(im);
+            break;
+        }
+        clock_gettime(CLOCK_MONOTONIC, &ts);
+        tns = (uint64_t)ts.tv_sec * 1000000000ull + (uint64_t)ts.tv_nsec;
+        rh[0] = (uint32_t)wa.width;
+        rh[1] = (uint32_t)wa.height;
+        rh[2] = (uint32_t)wa.width * 4;
+        rh[3] = 32;
+        fwrite(m, 1, 4, f);
+        fwrite(rh, 4, 4, f);
+        fwrite(&tns, 8, 1, f);
+        fwrite(&seq, 8, 1, f);
+        for (y = 0; y < wa.height; y++)
+            fwrite(im->data + (size_t)y * im->bytes_per_line, 1,
+                   (size_t)wa.width * 4, f);
+        fflush(f);
+        seq++;
+        XDestroyImage(im);
+        if (pace)
+            usleep(pace);
+        if ((seq & 63) == 0)
+            fprintf(stderr, "xgrab: frames=%llu\n",
+                    (unsigned long long)seq);
+    }
+    {
+        char m[4] = { 'G', 'Z', 'F', '2' };
+        uint64_t end = 0xFFFFFFFFFFFFFFFFull;
+
+        fwrite(m, 1, 4, f);
+        fwrite(&end, 8, 1, f);
+        fflush(f);
+    }
+    fclose(f);
+    XCloseDisplay(d);
+    fprintf(stderr, "xgrab: done frames=%llu\n", (unsigned long long)seq);
+    return 0;
+}