[Qemu-devel] [PATCH 1/3] qemu-io: Let -c abort raise any signal

[Max Reitz <mreitz@redhat.com>]

abort() has the sometimes undesirable side-effect of generating a core
dump. If that is not needed, SIGKILL has the same effect of abruptly
crash qemu; without a core dump.

Therefore, this patch allows to use the qemu-io abort command to raise
any signal.

Signed-off-by: Max Reitz <mreitz@redhat.com>
---
 qemu-io-cmds.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 56 insertions(+), 3 deletions(-)

diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c
index d94fb1e..5d39cf4 100644
--- a/qemu-io-cmds.c
+++ b/qemu-io-cmds.c
@@ -2036,18 +2036,71 @@ static const cmdinfo_t wait_break_cmd = {
        .oneline        = "waits for the suspension of a request",
 };
 
-static int abort_f(BlockDriverState *bs, int argc, char **argv)
+
+static void abort_help(void)
 {
-    abort();
+    printf(
+"\n"
+" simulates a program crash\n"
+"\n"
+" Invokes abort(), or raise(signal) if a signal number is specified.\n"
+" -S, -- number of the signal to raise()\n"
+"\n");
 }
 
+static int abort_f(BlockDriverState *bs, int argc, char **argv);
+
 static const cmdinfo_t abort_cmd = {
        .name           = "abort",
        .cfunc          = abort_f,
+       .argmin         = 0,
+       .argmax         = 2,
        .flags          = CMD_NOFILE_OK,
-       .oneline        = "simulate a program crash using abort(3)",
+       .args           = "[-S signal]",
+       .oneline        = "simulate a program crash",
+       .help           = abort_help,
 };
 
+static int abort_f(BlockDriverState *bs, int argc, char **argv)
+{
+    int c;
+    int sig = -1;
+
+    while ((c = getopt(argc, argv, "S:")) != EOF) {
+        switch (c) {
+            case 'S':
+                sig = cvtnum(optarg);
+                if (sig < 0) {
+                    printf("non-numeric signal number argument -- %s\n", optarg);
+                    return 0;
+                }
+                break;
+
+            default:
+                return qemuio_command_usage(&abort_cmd);
+        }
+    }
+
+    if (optind != argc) {
+        return qemuio_command_usage(&abort_cmd);
+    }
+
+    if (sig < 0) {
+        abort();
+    } else {
+        /* While abort() does flush all open streams, using raise() to kill this
+         * process does not necessarily. At least stdout and stderr (although
+         * the latter should be non-buffered anyway) should be flushed, though.
+         */
+        fflush(stdout);
+        fflush(stderr);
+
+        raise(sig);
+        /* raise() may return */
+        return 0;
+    }
+}
+
 static void sleep_cb(void *opaque)
 {
     bool *expired = opaque;
-- 
1.9.3