test: Add a test for a crash in bigreqs.

The failing struct comes from the python test written by Michal Srb
<msrb@suse.com>.  However, that test the crash by setting the server
to big-endian mode so we tried to swap a bunch of polylines data.  Any
clever ideas for something better?

Signed-off-by: Eric Anholt <eric@anholt.net>

test/bigreq/meson.build

@@ -0,0 +1,9 @@
+xcb_dep = dependency('xcb', required: false)
+xcb_sync_dep = dependency('xcb-sync', required: false)
+
+if get_option('xvfb')
+    if xcb_dep.found()
+        requestlength = executable('request-length', 'request-length.c', dependencies: xcb_dep)
+        test('request-length', simple_xinit, args: [requestlength, '--', xvfb_server])
+    endif
+endif

test/bigreq/request-length.c

@@ -0,0 +1,64 @@
+/*
+ * Copyright © 2017 Broadcom
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <poll.h>
+#include <xcb/xcb.h>
+#include <xcb/bigreq.h>
+
+int main(int argc, char **argv)
+{
+    int screen;
+    xcb_connection_t *c = xcb_connect(NULL, &screen);
+    int fd = xcb_get_file_descriptor(c);
+    struct {
+        uint8_t reqtype;
+        uint8_t coordmode;
+        uint16_t length;
+        uint32_t length_bigreq;
+        uint32_t drawable;
+        uint32_t gc;
+    } polyline_req = {
+        .reqtype = XCB_POLY_LINE,
+
+        /* This is the value that triggers the bug. */
+        .length_bigreq = 0,
+    };
+
+    free(xcb_big_requests_enable_reply(c, xcb_big_requests_enable(c), NULL));
+
+    /* Manually write out the bad request.  XCB can't help us here.*/
+    write(fd, &polyline_req, sizeof(polyline_req));
+
+    /* Block until the server has processed our mess.  If the server
+     * crashes, the simple-xinit will return failure.
+     */
+    struct pollfd pfd = {
+        .fd = fd,
+        .events = POLLIN,
+    };
+    poll(&pfd, 1, -1);
+
+    return 0;
+}

test/meson.build

@@ -23,4 +23,5 @@ if get_option('xvfb')
     endif
 endif
 
+subdir('bigreq')
 subdir('sync')