vl.c: Add '-L help' which lists data dirs.

QEMU compiles a list of data directories from various sources.  When
consuming a QEMU binary it's useful to be able to get this list of
data directories: a primary reason is so you can list what BIOSes or
keymaps ship with this version of QEMU.  However without reproducing
the method that QEMU uses internally, it's not possible to get the
list of data directories.

This commit adds a simple '-L help' option that just lists out the
data directories as qemu calculates them:

$ ./x86_64-softmmu/qemu-system-x86_64 -L help
/home/rjones/d/qemu/pc-bios
/usr/local/share/qemu

$ ./x86_64-softmmu/qemu-system-x86_64 -L /tmp -L help
/tmp
/home/rjones/d/qemu/pc-bios
/usr/local/share/qemu

Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1463416475-11728-2-git-send-email-rjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/qemu-options.hx b/qemu-options.hx
index 0e42ba55bea8442c3fbb0e26e3d7aed74761f745..17f15ad1fe4a221ab19db82e65e54e060323a33e 100644 (file)
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -3214,6 +3214,8 @@ STEXI
 @item -L  @var{path}
 @findex -L
 Set the directory for the BIOS, VGA BIOS and keymaps.
+
+To list all the data directories, use @code{-L help}.
 ETEXI
 
 DEF("bios", HAS_ARG, QEMU_OPTION_bios, \

diff --git a/vl.c b/vl.c
index 45eff5661b207af1ae8d165540cb0b06fafe8e79..fb18821fb913f07bf331a8335a8c89726ca47153 100644 (file)
--- a/vl.c
+++ b/vl.c
@@ -2968,6 +2968,7 @@ int main(int argc, char **argv, char **envp)
     FILE *vmstate_dump_file = NULL;
     Error *main_loop_err = NULL;
     Error *err = NULL;
+    bool list_data_dirs = false;
 
     qemu_init_cpu_loop();
     qemu_mutex_lock_iothread();
@@ -3354,7 +3355,9 @@ int main(int argc, char **argv, char **envp)
                 add_device_config(DEV_GDB, optarg);
                 break;
             case QEMU_OPTION_L:
-                if (data_dir_idx < ARRAY_SIZE(data_dir)) {
+                if (is_help_option(optarg)) {
+                    list_data_dirs = true;
+                } else if (data_dir_idx < ARRAY_SIZE(data_dir)) {
                     data_dir[data_dir_idx++] = optarg;
                 }
                 break;
@@ -4086,6 +4089,14 @@ int main(int argc, char **argv, char **envp)
         data_dir[data_dir_idx++] = CONFIG_QEMU_DATADIR;
     }
 
+    /* -L help lists the data directories and exits. */
+    if (list_data_dirs) {
+        for (i = 0; i < data_dir_idx; i++) {
+            printf("%s\n", data_dir[i]);
+        }
+        exit(0);
+    }
+
     smp_parse(qemu_opts_find(qemu_find_opts("smp-opts"), NULL));
 
     machine_class->max_cpus = machine_class->max_cpus ?: 1; /* Default to UP */