Support 'help' as a synonym for '?' in command line options
For command line options which permit '?' meaning 'please list the
permitted values', add support for 'help' as a synonym, by abstracting
the check out into a helper function.
This change means that in some cases where we were being lazy in
our string parsing, "?junk" will now be rejected as an invalid option
rather than being (undocumentedly) treated the same way as "?".
Update the documentation to use 'help' rather than '?', since '?'
is a shell metacharacter and thus prone to fail confusingly if there
is a single character filename in the current working directory and
the '?' has not been escaped. It's therefore better to steer users
towards 'help', though '?' is retained for backwards compatibility.
We do not, however, update the output of the system emulator's -help
(or any documentation autogenerated from the qemu-options.hx which
is the source of the -help text) because libvirt parses our -help
output and will break. At a later date when QEMU provides a better
interface so libvirt can avoid having to do this, we can update the
-help text too.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/arch_init.c b/arch_init.c
index 26f30ef..60823ba 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -680,7 +680,7 @@
{
struct soundhw *c;
- if (*optarg == '?') {
+ if (is_help_option(optarg)) {
show_valid_cards:
printf("Valid sound card names (comma separated):\n");
@@ -688,7 +688,7 @@
printf ("%-11s %s\n", c->name, c->descr);
}
printf("\n-soundhw all will enable all of the above\n");
- exit(*optarg != '?');
+ exit(!is_help_option(optarg));
}
else {
size_t l;
diff --git a/blockdev.c b/blockdev.c
index 3d75015..8669142 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -398,11 +398,11 @@
#endif
if ((buf = qemu_opt_get(opts, "format")) != NULL) {
- if (strcmp(buf, "?") == 0) {
- error_printf("Supported formats:");
- bdrv_iterate_format(bdrv_format_print, NULL);
- error_printf("\n");
- return NULL;
+ if (is_help_option(buf)) {
+ error_printf("Supported formats:");
+ bdrv_iterate_format(bdrv_format_print, NULL);
+ error_printf("\n");
+ return NULL;
}
drv = bdrv_find_whitelisted_format(buf);
if (!drv) {
diff --git a/bsd-user/main.c b/bsd-user/main.c
index cd33d65..095ae8e 100644
--- a/bsd-user/main.c
+++ b/bsd-user/main.c
@@ -681,7 +681,7 @@
"-g port wait gdb connection to port\n"
"-L path set the elf interpreter prefix (default=%s)\n"
"-s size set the stack size in bytes (default=%ld)\n"
- "-cpu model select CPU (-cpu ? for list)\n"
+ "-cpu model select CPU (-cpu help for list)\n"
"-drop-ld-preload drop LD_PRELOAD for target process\n"
"-E var=value sets/modifies targets environment variable(s)\n"
"-U var unsets targets environment variable(s)\n"
@@ -825,7 +825,7 @@
qemu_uname_release = argv[optind++];
} else if (!strcmp(r, "cpu")) {
cpu_model = argv[optind++];
- if (strcmp(cpu_model, "?") == 0) {
+ if (is_help_option(cpu_model)) {
/* XXX: implement xxx_cpu_list for targets that still miss it */
#if defined(cpu_list)
cpu_list(stdout, &fprintf);
diff --git a/hw/mips_jazz.c b/hw/mips_jazz.c
index bf1b799..db927f1 100644
--- a/hw/mips_jazz.c
+++ b/hw/mips_jazz.c
@@ -239,7 +239,7 @@
dp83932_init(nd, 0x80001000, 2, get_system_memory(), rc4030[4],
rc4030_opaque, rc4030_dma_memory_rw);
break;
- } else if (strcmp(nd->model, "?") == 0) {
+ } else if (is_help_option(nd->model)) {
fprintf(stderr, "qemu: Supported NICs: dp83932\n");
exit(1);
} else {
diff --git a/hw/qdev-monitor.c b/hw/qdev-monitor.c
index 7915b45..b22a37a 100644
--- a/hw/qdev-monitor.c
+++ b/hw/qdev-monitor.c
@@ -138,13 +138,13 @@
ObjectClass *klass;
driver = qemu_opt_get(opts, "driver");
- if (driver && !strcmp(driver, "?")) {
+ if (driver && is_help_option(driver)) {
bool show_no_user = false;
object_class_foreach(qdev_print_devinfo, TYPE_DEVICE, false, &show_no_user);
return 1;
}
- if (!driver || !qemu_opt_get(opts, "?")) {
+ if (!driver || !qemu_opt_has_help_opt(opts)) {
return 0;
}
diff --git a/hw/watchdog.c b/hw/watchdog.c
index a42124d..b52aced 100644
--- a/hw/watchdog.c
+++ b/hw/watchdog.c
@@ -55,7 +55,7 @@
QemuOpts *opts;
/* -watchdog ? lists available devices and exits cleanly. */
- if (strcmp(p, "?") == 0) {
+ if (is_help_option(p)) {
QLIST_FOREACH(model, &watchdog_list, entry) {
fprintf(stderr, "\t%s\t%s\n",
model->wdt_name, model->wdt_description);
diff --git a/linux-user/main.c b/linux-user/main.c
index a0ab8e8..25eaa11 100644
--- a/linux-user/main.c
+++ b/linux-user/main.c
@@ -3140,7 +3140,7 @@
static void handle_arg_cpu(const char *arg)
{
cpu_model = strdup(arg);
- if (cpu_model == NULL || strcmp(cpu_model, "?") == 0) {
+ if (cpu_model == NULL || is_help_option(cpu_model)) {
/* XXX: implement xxx_cpu_list for targets that still miss it */
#if defined(cpu_list_id)
cpu_list_id(stdout, &fprintf, "");
@@ -3231,7 +3231,7 @@
{"s", "QEMU_STACK_SIZE", true, handle_arg_stack_size,
"size", "set the stack size to 'size' bytes"},
{"cpu", "QEMU_CPU", true, handle_arg_cpu,
- "model", "select CPU (-cpu ? for list)"},
+ "model", "select CPU (-cpu help for list)"},
{"E", "QEMU_SET_ENV", true, handle_arg_set_env,
"var=value", "sets targets environment variable (see below)"},
{"U", "QEMU_UNSET_ENV", true, handle_arg_unset_env,
diff --git a/net.c b/net.c
index dbca77b..32ca50e 100644
--- a/net.c
+++ b/net.c
@@ -691,8 +691,9 @@
{
int i;
- if (!arg || strcmp(arg, "?"))
+ if (!arg || !is_help_option(arg)) {
return 0;
+ }
fprintf(stderr, "qemu: Supported NIC models: ");
for (i = 0 ; models[i]; i++)
diff --git a/qemu-common.h b/qemu-common.h
index d26ff39..dd91912 100644
--- a/qemu-common.h
+++ b/qemu-common.h
@@ -136,6 +136,24 @@
void qemu_get_timedate(struct tm *tm, int offset);
int qemu_timedate_diff(struct tm *tm);
+/**
+ * is_help_option:
+ * @s: string to test
+ *
+ * Check whether @s is one of the standard strings which indicate
+ * that the user is asking for a list of the valid values for a
+ * command option like -cpu or -M. The current accepted strings
+ * are 'help' and '?'. '?' is deprecated (it is a shell wildcard
+ * which makes it annoying to use in a reliable way) but provided
+ * for backwards compatibility.
+ *
+ * Returns: true if @s is a request for a list.
+ */
+static inline bool is_help_option(const char *s)
+{
+ return !strcmp(s, "?") || !strcmp(s, "help");
+}
+
/* cutils.c */
void pstrcpy(char *buf, int buf_size, const char *str);
void strpadcpy(char *buf, int buf_size, const char *str, char pad);
diff --git a/qemu-doc.texi b/qemu-doc.texi
index 84dad19..a41448a 100644
--- a/qemu-doc.texi
+++ b/qemu-doc.texi
@@ -2390,7 +2390,7 @@
@item -s size
Set the x86 stack size in bytes (default=524288)
@item -cpu model
-Select CPU model (-cpu ? for list and additional feature selection)
+Select CPU model (-cpu help for list and additional feature selection)
@item -ignore-environment
Start with an empty environment. Without this option,
the initial environment is a copy of the caller's environment.
diff --git a/qemu-ga.c b/qemu-ga.c
index 8199da7..f1a39ec 100644
--- a/qemu-ga.c
+++ b/qemu-ga.c
@@ -736,7 +736,7 @@
break;
case 'b': {
char **list_head, **list;
- if (*optarg == '?') {
+ if (is_help_option(optarg)) {
list_head = list = qmp_get_command_list();
while (*list != NULL) {
printf("%s\n", *list);
diff --git a/qemu-img.c b/qemu-img.c
index 80cfb9b..b866f80 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -350,7 +350,7 @@
img_size = (uint64_t)sval;
}
- if (options && !strcmp(options, "?")) {
+ if (options && is_help_option(options)) {
ret = print_block_option_help(filename, fmt);
goto out;
}
@@ -744,7 +744,7 @@
/* Initialize before goto out */
qemu_progress_init(progress, 2.0);
- if (options && !strcmp(options, "?")) {
+ if (options && is_help_option(options)) {
ret = print_block_option_help(out_filename, out_fmt);
goto out;
}
diff --git a/qemu-option.c b/qemu-option.c
index 8334190..27891e7 100644
--- a/qemu-option.c
+++ b/qemu-option.c
@@ -529,6 +529,18 @@
return opt ? opt->str : NULL;
}
+bool qemu_opt_has_help_opt(QemuOpts *opts)
+{
+ QemuOpt *opt;
+
+ QTAILQ_FOREACH_REVERSE(opt, &opts->head, QemuOptHead, next) {
+ if (is_help_option(opt->name)) {
+ return true;
+ }
+ }
+ return false;
+}
+
bool qemu_opt_get_bool(QemuOpts *opts, const char *name, bool defval)
{
QemuOpt *opt = qemu_opt_find(opts, name);
diff --git a/qemu-option.h b/qemu-option.h
index 951dec3..ca72986 100644
--- a/qemu-option.h
+++ b/qemu-option.h
@@ -107,6 +107,18 @@
};
const char *qemu_opt_get(QemuOpts *opts, const char *name);
+/**
+ * qemu_opt_has_help_opt:
+ * @opts: options to search for a help request
+ *
+ * Check whether the options specified by @opts include one of the
+ * standard strings which indicate that the user is asking for a
+ * list of the valid values for a command line option (as defined
+ * by is_help_option()).
+ *
+ * Returns: true if @opts includes 'help' or equivalent.
+ */
+bool qemu_opt_has_help_opt(QemuOpts *opts);
bool qemu_opt_get_bool(QemuOpts *opts, const char *name, bool defval);
uint64_t qemu_opt_get_number(QemuOpts *opts, const char *name, uint64_t defval);
uint64_t qemu_opt_get_size(QemuOpts *opts, const char *name, uint64_t defval);
diff --git a/qemu-options.hx b/qemu-options.hx
index dc68e15..9277414 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -6,6 +6,10 @@
HXCOMM architectures.
HXCOMM HXCOMM can be used for comments, discarded from both texi and C
+HXCOMM TODO : when we are able to change -help output without breaking
+HXCOMM libvirt we should update the help options which refer to -cpu ?,
+HXCOMM -driver ?, etc to use the preferred -cpu help etc instead.
+
DEFHEADING(Standard options:)
STEXI
@table @option
diff --git a/qemu-timer.c b/qemu-timer.c
index de98977..062fdf2 100644
--- a/qemu-timer.c
+++ b/qemu-timer.c
@@ -183,7 +183,7 @@
char *name;
struct qemu_alarm_timer tmp;
- if (!strcmp(opt, "?")) {
+ if (is_help_option(opt)) {
show_available_alarms();
exit(0);
}
diff --git a/vl.c b/vl.c
index 9fea320..1fd1114 100644
--- a/vl.c
+++ b/vl.c
@@ -2086,7 +2086,7 @@
printf("%-20s %s%s\n", m->name, m->desc,
m->is_default ? " (default)" : "");
}
- exit(!name || *name != '?');
+ exit(!name || !is_help_option(name));
}
static int tcg_init(void)
@@ -3216,7 +3216,7 @@
*/
cpudef_init();
- if (cpu_model && *cpu_model == '?') {
+ if (cpu_model && is_help_option(cpu_model)) {
list_cpus(stdout, &fprintf, cpu_model);
exit(0);
}
