Set the framework up for declaring integer options with an integer
default, instead of our current insane approach of requiring the
default value to be given as a string (which then has to be reparsed
at every use that wants a number). git grep '[^.]def_value_str' says
that we have done a good job of NOT abusing the internal field
outside of the implementation in qemu-option.c; therefore, it is not
too hard to audit that all code can either handle the new integer
defaults correctly or abort because a caller violated constraints.
Sadly, we DO have a constraint that qemu_opt_get() should not be
called on an option that has an integer type, because we have no
where to stash a cached const char * result; but callers that want
an integer should be using qemu_opt_get_number() and friends
anyways.
Signed-off-by: Eric Blake <ebl...@redhat.com>
---
include/qemu/option.h | 12 ++++++++
util/qemu-option.c | 69 +++++++++++++++++++++++++++++++++++++------
2 files changed, 72 insertions(+), 9 deletions(-)
diff --git a/include/qemu/option.h b/include/qemu/option.h
index 844587cab39..46b80d5a6e1 100644
--- a/include/qemu/option.h
+++ b/include/qemu/option.h
@@ -46,6 +46,18 @@ typedef struct QemuOptDesc {
const char *name;
enum QemuOptType type;
const char *help;
+ /*
+ * For QEMU_OPT_STRING: Leave def_value_int 0, and set def_value_str
+ * to a default value or leave NULL for no default.
+ *
+ * For other types: Initialize at most non-zero def_value_int or a
+ * parseable def_value_str for a default (must use a string for an
+ * explicit default of 0, although an implicit default generally
+ * works). If setting def_value_int, calling qemu_opt_get() on
+ * that option will abort(); instead, call qemu_opt_get_del() or a
+ * typed getter.
+ */
+ uint64_t def_value_int;
const char *def_value_str;
} QemuOptDesc;
diff --git a/util/qemu-option.c b/util/qemu-option.c
index de42e2a406a..06c4e8102a8 100644
--- a/util/qemu-option.c
+++ b/util/qemu-option.c
@@ -321,7 +321,8 @@ const char *qemu_opt_get(QemuOpts *opts, const char *name)
opt = qemu_opt_find(opts, name);
if (!opt) {
const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
- if (desc && desc->def_value_str) {
+ if (desc) {
+ assert(!desc->def_value_int);
return desc->def_value_str;
}
}
@@ -364,8 +365,22 @@ char *qemu_opt_get_del(QemuOpts *opts, const char *name)
opt = qemu_opt_find(opts, name);
if (!opt) {
desc = find_desc_by_name(opts->list->desc, name);
- if (desc && desc->def_value_str) {
- str = g_strdup(desc->def_value_str);
+ if (desc) {
+ if (desc->def_value_str) {
+ str = g_strdup(desc->def_value_str);
+ } else if (desc->def_value_int) {
+ switch (desc->type) {
+ case QEMU_OPT_BOOL:
+ str = g_strdup("on");
+ break;
+ case QEMU_OPT_NUMBER:
+ case QEMU_OPT_SIZE:
+ str = g_strdup_printf("%" PRId64, desc->def_value_int);
+ break;
+ default:
+ abort();
+ }
+ }
}
return str;
}
@@ -400,8 +415,15 @@ static bool qemu_opt_get_bool_helper(QemuOpts *opts, const
char *name,
opt = qemu_opt_find(opts, name);
if (opt == NULL) {
const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
- if (desc && desc->def_value_str) {
- parse_option_bool(name, desc->def_value_str, &ret, &error_abort);
+ if (desc) {
+ if (desc->def_value_int) {
+ assert(desc->type != QEMU_OPT_STRING);
+ return true;
+ }
+ if (desc->def_value_str) {
+ parse_option_bool(name, desc->def_value_str, &ret,
+ &error_abort);
+ }
}
return ret;
}
@@ -436,8 +458,15 @@ static uint64_t qemu_opt_get_number_helper(QemuOpts *opts,
const char *name,
opt = qemu_opt_find(opts, name);
if (opt == NULL) {
const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
- if (desc && desc->def_value_str) {
- parse_option_number(name, desc->def_value_str, &ret, &error_abort);
+ if (desc) {
+ if (desc->def_value_int) {
+ assert(desc->type != QEMU_OPT_STRING);
+ return desc->def_value_int;
+ }
+ if (desc->def_value_str) {
+ parse_option_number(name, desc->def_value_str, &ret,
+ &error_abort);
+ }
}
return ret;
}
@@ -473,8 +502,15 @@ static uint64_t qemu_opt_get_size_helper(QemuOpts *opts,
const char *name,
opt = qemu_opt_find(opts, name);
if (opt == NULL) {
const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
- if (desc && desc->def_value_str) {
- parse_option_size(name, desc->def_value_str, &ret, &error_abort);
+ if (desc) {
+ if (desc->def_value_int) {
+ assert(desc->type != QEMU_OPT_STRING);
+ return desc->def_value_int;
+ }
+ if (desc->def_value_str) {
+ parse_option_size(name, desc->def_value_str, &ret,
+ &error_abort);
+ }
}
return ret;
}
@@ -787,9 +823,23 @@ void qemu_opts_print(QemuOpts *opts, const char *separator)
}
for (; desc && desc->name; desc++) {
const char *value;
+ char *tmp = NULL;
opt = qemu_opt_find(opts, desc->name);
value = opt ? opt->str : desc->def_value_str;
+ if (!value && desc->def_value_int) {
+ switch (desc->type) {
+ case QEMU_OPT_BOOL:
+ value = tmp = g_strdup("on");
+ break;
+ case QEMU_OPT_NUMBER:
+ case QEMU_OPT_SIZE:
+ value = tmp = g_strdup_printf("%" PRId64, desc->def_value_int);
+ break;
+ default:
+ abort();
+ }
+ }
if (!value) {
continue;
}
@@ -803,6 +853,7 @@ void qemu_opts_print(QemuOpts *opts, const char *separator)
printf("%s%s=%s", sep, desc->name, value);
}
sep = separator;
+ g_free(tmp);
}
}
--
2.20.1
