diff options
| author | Max Reitz <mreitz@redhat.com> | 2016-09-28 22:46:42 +0200 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2016-10-24 17:54:03 +0200 |
| commit | ffb31e1da7d3e044649717c4ebcb1768b5b44299 (patch) | |
| tree | e925b31c89fc80a027cd36dd276480e8a85b2b75 | |
| parent | a26ddb43963e77aeebc2a4f011d27b2d9c017f21 (diff) | |
qemu-nbd: Add --fork option
Using the --fork option, one can make qemu-nbd fork the worker process.
The original process will exit on error of the worker or once the worker
enters the main loop.
Suggested-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| -rw-r--r-- | qemu-nbd.c | 17 | ||||
| -rw-r--r-- | qemu-nbd.texi | 2 |
2 files changed, 18 insertions, 1 deletions
diff --git a/qemu-nbd.c b/qemu-nbd.c index cca4a983b7..b757dc7621 100644 --- a/qemu-nbd.c +++ b/qemu-nbd.c @@ -48,6 +48,7 @@ #define QEMU_NBD_OPT_OBJECT 260 #define QEMU_NBD_OPT_TLSCREDS 261 #define QEMU_NBD_OPT_IMAGE_OPTS 262 +#define QEMU_NBD_OPT_FORK 263 #define MBR_SIZE 512 @@ -92,6 +93,8 @@ static void usage(const char *name) " passwords and/or encryption keys\n" " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" " specify tracing options\n" +" --fork fork off the server process and exit the parent\n" +" once the server is running\n" #ifdef __linux__ "Kernel NBD client support:\n" " -c, --connect=DEV connect FILE to the local NBD device DEV\n" @@ -503,6 +506,7 @@ int main(int argc, char **argv) { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, { "trace", required_argument, NULL, 'T' }, + { "fork", no_argument, NULL, QEMU_NBD_OPT_FORK }, { NULL, 0, NULL, 0 } }; int ch; @@ -524,6 +528,8 @@ int main(int argc, char **argv) bool imageOpts = false; bool writethrough = true; char *trace_file = NULL; + bool fork_process = false; + int old_stderr = -1; /* The client thread uses SIGTERM to interrupt the server. A signal * handler ensures that "qemu-nbd -v -c" exits with a nice status code. @@ -715,6 +721,9 @@ int main(int argc, char **argv) g_free(trace_file); trace_file = trace_opt_parse(optarg); break; + case QEMU_NBD_OPT_FORK: + fork_process = true; + break; } } @@ -774,7 +783,7 @@ int main(int argc, char **argv) return 0; } - if (device && !verbose) { + if ((device && !verbose) || fork_process) { int stderr_fd[2]; pid_t pid; int ret; @@ -797,6 +806,7 @@ int main(int argc, char **argv) ret = qemu_daemon(1, 0); /* Temporarily redirect stderr to the parent's pipe... */ + old_stderr = dup(STDERR_FILENO); dup2(stderr_fd[1], STDERR_FILENO); if (ret < 0) { error_report("Failed to daemonize: %s", strerror(errno)); @@ -960,6 +970,11 @@ int main(int argc, char **argv) exit(EXIT_FAILURE); } + if (fork_process) { + dup2(old_stderr, STDERR_FILENO); + close(old_stderr); + } + state = RUNNING; do { main_loop_wait(false); diff --git a/qemu-nbd.texi b/qemu-nbd.texi index 91ebf04b5b..b7a9c6d02f 100644 --- a/qemu-nbd.texi +++ b/qemu-nbd.texi @@ -86,6 +86,8 @@ the new style NBD protocol negotiation Enable mandatory TLS encryption for the server by setting the ID of the TLS credentials object previously created with the --object option. +@item --fork +Fork off the server process and exit the parent once the server is running. @item -v, --verbose Display extra debugging information @item -h, --help |