qapi: Add human mode to StringOutputVisitor

This will be used by "info qtree".  For numbers it prints both the
decimal and hex values.  For sizes it rounds to the nearest power
of 2^10.  For strings, it puts quotes around the string and separates
NULL and empty string.

Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>

7 files changed, 60 insertions, 10 deletions

diff --git a/include/qapi/string-output-visitor.h b/include/qapi/string-output-visitor.h
index ec81e42..d99717f 100644
--- a/include/qapi/string-output-visitor.h
+++ b/include/qapi/string-output-visitor.h
@@ -17,7 +17,7 @@
 
 typedef struct StringOutputVisitor StringOutputVisitor;
 
-StringOutputVisitor *string_output_visitor_new(void);
+StringOutputVisitor *string_output_visitor_new(bool human);
 void string_output_visitor_cleanup(StringOutputVisitor *v);
 
 char *string_output_get_string(StringOutputVisitor *v);
diff --git a/include/qom/object.h b/include/qom/object.h
index e0ff212..9c7c361 100644
--- a/include/qom/object.h
+++ b/include/qom/object.h
@@ -946,12 +946,13 @@ void object_property_parse(Object *obj, const char *string,
  * object_property_print:
  * @obj: the object
  * @name: the name of the property
+ * @human: if true, print for human consumption
  * @errp: returns an error if this function fails
  *
  * Returns a string representation of the value of the property.  The
  * caller shall free the string.
  */
-char *object_property_print(Object *obj, const char *name,
+char *object_property_print(Object *obj, const char *name, bool human,
                             Error **errp);
 
 /**
diff --git a/qapi/string-output-visitor.c b/qapi/string-output-visitor.c
index 921653d..67a8798 100644
--- a/qapi/string-output-visitor.c
+++ b/qapi/string-output-visitor.c
@@ -14,10 +14,12 @@
 #include "qapi/string-output-visitor.h"
 #include "qapi/visitor-impl.h"
 #include "qapi/qmp/qerror.h"
+#include "qemu/host-utils.h"
 
 struct StringOutputVisitor
 {
     Visitor visitor;
+    bool human;
     char *string;
 };
 
@@ -31,7 +33,45 @@ static void print_type_int(Visitor *v, int64_t *obj, const char *name,
                            Error **errp)
 {
     StringOutputVisitor *sov = DO_UPCAST(StringOutputVisitor, visitor, v);
-    string_output_set(sov, g_strdup_printf("%lld", (long long) *obj));
+    char *out;
+
+    if (sov->human) {
+        out = g_strdup_printf("%lld (%#llx)", (long long) *obj, (long long) *obj);
+    } else {
+        out = g_strdup_printf("%lld", (long long) *obj);
+    }
+    string_output_set(sov, out);
+}
+
+static void print_type_size(Visitor *v, uint64_t *obj, const char *name,
+                           Error **errp)
+{
+    StringOutputVisitor *sov = DO_UPCAST(StringOutputVisitor, visitor, v);
+    static const char suffixes[] = { 'B', 'K', 'M', 'G', 'T' };
+    uint64_t div, val;
+    char *out;
+    int i;
+
+    if (!sov->human) {
+        out = g_strdup_printf("%llu", (long long) *obj);
+        string_output_set(sov, out);
+        return;
+    }
+
+    val = *obj;
+
+    /* Compute floor(log2(val)).  */
+    i = 64 - clz64(val);
+
+    /* Find the power of 1024 that we'll display as the units.  */
+    i /= 10;
+    if (i >= ARRAY_SIZE(suffixes)) {
+        i = ARRAY_SIZE(suffixes) - 1;
+    }
+    div = 1ULL << (i * 10);
+
+    out = g_strdup_printf("%0.03f%c", (double)val/div, suffixes[i]);
+    string_output_set(sov, out);
 }
 
 static void print_type_bool(Visitor *v, bool *obj, const char *name,
@@ -45,7 +85,14 @@ static void print_type_str(Visitor *v, char **obj, const char *name,
                            Error **errp)
 {
     StringOutputVisitor *sov = DO_UPCAST(StringOutputVisitor, visitor, v);
-    string_output_set(sov, g_strdup(*obj ? *obj : ""));
+    char *out;
+
+    if (sov->human) {
+        out = *obj ? g_strdup_printf("\"%s\"", *obj) : g_strdup("<null>");
+    } else {
+        out = g_strdup(*obj ? *obj : "");
+    }
+    string_output_set(sov, out);
 }
 
 static void print_type_number(Visitor *v, double *obj, const char *name,
@@ -73,14 +120,16 @@ void string_output_visitor_cleanup(StringOutputVisitor *sov)
     g_free(sov);
 }
 
-StringOutputVisitor *string_output_visitor_new(void)
+StringOutputVisitor *string_output_visitor_new(bool human)
 {
     StringOutputVisitor *v;
 
     v = g_malloc0(sizeof(*v));
 
+    v->human = human;
     v->visitor.type_enum = output_type_enum;
     v->visitor.type_int = print_type_int;
+    v->visitor.type_size = print_type_size;
     v->visitor.type_bool = print_type_bool;
     v->visitor.type_str = print_type_str;
     v->visitor.type_number = print_type_number;
diff --git a/qdev-monitor.c b/qdev-monitor.c
index 4d1634c..f385fb3 100644
--- a/qdev-monitor.c
+++ b/qdev-monitor.c
@@ -577,7 +577,7 @@ static void qdev_print_props(Monitor *mon, DeviceState *dev, Property *props,
         if (object_property_get_type(OBJECT(dev), legacy_name, NULL)) {
             value = object_property_get_str(OBJECT(dev), legacy_name, &err);
         } else {
-            value = object_property_print(OBJECT(dev), props->name, &err);
+            value = object_property_print(OBJECT(dev), props->name, false, &err);
         }
         g_free(legacy_name);
 
diff --git a/qom/object.c b/qom/object.c
index 62e7e41..660859c 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -948,13 +948,13 @@ void object_property_parse(Object *obj, const char *string,
     string_input_visitor_cleanup(mi);
 }
 
-char *object_property_print(Object *obj, const char *name,
+char *object_property_print(Object *obj, const char *name, bool human,
                             Error **errp)
 {
     StringOutputVisitor *mo;
     char *string;
 
-    mo = string_output_visitor_new();
+    mo = string_output_visitor_new(human);
     object_property_get(obj, string_output_get_visitor(mo), name, errp);
     string = string_output_get_string(mo);
     string_output_visitor_cleanup(mo);
diff --git a/tests/test-string-output-visitor.c b/tests/test-string-output-visitor.c
index 79d815f..56cc21d 100644
--- a/tests/test-string-output-visitor.c
+++ b/tests/test-string-output-visitor.c
@@ -26,7 +26,7 @@ typedef struct TestOutputVisitorData {
 static void visitor_output_setup(TestOutputVisitorData *data,
                                  const void *unused)
 {
-    data->sov = string_output_visitor_new();
+    data->sov = string_output_visitor_new(false);
     g_assert(data->sov != NULL);
 
     data->ov = string_output_get_visitor(data->sov);
diff --git a/tests/test-visitor-serialization.c b/tests/test-visitor-serialization.c
index 9aaa587..6bff950 100644
--- a/tests/test-visitor-serialization.c
+++ b/tests/test-visitor-serialization.c
@@ -1083,7 +1083,7 @@ static void string_serialize(void *native_in, void **datap,
 {
     StringSerializeData *d = g_malloc0(sizeof(*d));
 
-    d->sov = string_output_visitor_new();
+    d->sov = string_output_visitor_new(false);
     visit(string_output_get_visitor(d->sov), &native_in, errp);
     *datap = d;
 }