qapi: make string output visitor parse int list

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

MST: split up patch
diff --git a/qapi/string-output-visitor.c b/qapi/string-output-visitor.c
index fb1d2e8..1c0834a 100644
--- a/qapi/string-output-visitor.c
+++ b/qapi/string-output-visitor.c
@@ -16,32 +16,181 @@
 #include "qapi/qmp/qerror.h"
 #include "qemu/host-utils.h"
 #include <math.h>
+#include "qemu/range.h"
+
+enum ListMode {
+    LM_NONE,             /* not traversing a list of repeated options */
+    LM_STARTED,          /* start_list() succeeded */
+
+    LM_IN_PROGRESS,      /* next_list() has been called.
+                          *
+                          * Generating the next list link will consume the most
+                          * recently parsed QemuOpt instance of the repeated
+                          * option.
+                          *
+                          * Parsing a value into the list link will examine the
+                          * next QemuOpt instance of the repeated option, and
+                          * possibly enter LM_SIGNED_INTERVAL or
+                          * LM_UNSIGNED_INTERVAL.
+                          */
+
+    LM_SIGNED_INTERVAL,  /* next_list() has been called.
+                          *
+                          * Generating the next list link will consume the most
+                          * recently stored element from the signed interval,
+                          * parsed from the most recent QemuOpt instance of the
+                          * repeated option. This may consume QemuOpt itself
+                          * and return to LM_IN_PROGRESS.
+                          *
+                          * Parsing a value into the list link will store the
+                          * next element of the signed interval.
+                          */
+
+    LM_UNSIGNED_INTERVAL,/* Same as above, only for an unsigned interval. */
+
+    LM_END
+};
+
+typedef enum ListMode ListMode;
 
 struct StringOutputVisitor
 {
     Visitor visitor;
     bool human;
-    char *string;
+    GString *string;
+    bool head;
+    ListMode list_mode;
+    union {
+        int64_t s;
+        uint64_t u;
+    } range_start, range_end;
+    GList *ranges;
 };
 
 static void string_output_set(StringOutputVisitor *sov, char *string)
 {
-    g_free(sov->string);
-    sov->string = string;
+    if (sov->string) {
+        g_string_free(sov->string, true);
+    }
+    sov->string = g_string_new(string);
+    g_free(string);
+}
+
+static void string_output_append(StringOutputVisitor *sov, int64_t a)
+{
+    Range *r = g_malloc0(sizeof(*r));
+    r->begin = a;
+    r->end = a + 1;
+    sov->ranges = g_list_insert_sorted_merged(sov->ranges, r, range_compare);
+}
+
+static void string_output_append_range(StringOutputVisitor *sov,
+                                       int64_t s, int64_t e)
+{
+    Range *r = g_malloc0(sizeof(*r));
+    r->begin = s;
+    r->end = e + 1;
+    sov->ranges = g_list_insert_sorted_merged(sov->ranges, r, range_compare);
+}
+
+static void format_string(StringOutputVisitor *sov, Range *r, bool next,
+                          bool human)
+{
+    if (r->end - r->begin > 1) {
+        if (human) {
+            g_string_append_printf(sov->string, "%" PRIx64 "-%" PRIx64,
+                                   r->begin, r->end - 1);
+
+        } else {
+            g_string_append_printf(sov->string, "%" PRId64 "-%" PRId64,
+                                   r->begin, r->end - 1);
+        }
+    } else {
+        if (human) {
+            g_string_append_printf(sov->string, "%" PRIx64, r->begin);
+        } else {
+            g_string_append_printf(sov->string, "%" PRId64, r->begin);
+        }
+    }
+    if (next) {
+        g_string_append(sov->string, ",");
+    }
 }
 
 static void print_type_int(Visitor *v, int64_t *obj, const char *name,
                            Error **errp)
 {
     StringOutputVisitor *sov = DO_UPCAST(StringOutputVisitor, visitor, v);
-    char *out;
+    GList *l;
+
+    switch (sov->list_mode) {
+    case LM_NONE:
+        string_output_append(sov, *obj);
+        break;
+
+    case LM_STARTED:
+        sov->range_start.s = *obj;
+        sov->range_end.s = *obj;
+        sov->list_mode = LM_IN_PROGRESS;
+        return;
+
+    case LM_IN_PROGRESS:
+        if (sov->range_end.s + 1 == *obj) {
+            sov->range_end.s++;
+        } else {
+            if (sov->range_start.s == sov->range_end.s) {
+                string_output_append(sov, sov->range_end.s);
+            } else {
+                assert(sov->range_start.s < sov->range_end.s);
+                string_output_append_range(sov, sov->range_start.s,
+                                           sov->range_end.s);
+            }
+
+            sov->range_start.s = *obj;
+            sov->range_end.s = *obj;
+        }
+        return;
+
+    case LM_END:
+        if (sov->range_end.s + 1 == *obj) {
+            sov->range_end.s++;
+            assert(sov->range_start.s < sov->range_end.s);
+            string_output_append_range(sov, sov->range_start.s,
+                                       sov->range_end.s);
+        } else {
+            if (sov->range_start.s == sov->range_end.s) {
+                string_output_append(sov, sov->range_end.s);
+            } else {
+                assert(sov->range_start.s < sov->range_end.s);
+
+                string_output_append_range(sov, sov->range_start.s,
+                                           sov->range_end.s);
+            }
+            string_output_append(sov, *obj);
+        }
+        break;
+
+    default:
+        abort();
+    }
+
+    l = sov->ranges;
+    while (l) {
+        Range *r = l->data;
+        format_string(sov, r, l->next != NULL, false);
+        l = l->next;
+    }
 
     if (sov->human) {
-        out = g_strdup_printf("%lld (%#llx)", (long long) *obj, (long long) *obj);
-    } else {
-        out = g_strdup_printf("%lld", (long long) *obj);
+        l = sov->ranges;
+        g_string_append(sov->string, " (");
+        while (l) {
+            Range *r = l->data;
+            format_string(sov, r, l->next != NULL, false);
+            l = l->next;
+        }
+        g_string_append(sov->string, ")");
     }
-    string_output_set(sov, out);
 }
 
 static void print_type_size(Visitor *v, uint64_t *obj, const char *name,
@@ -103,9 +252,61 @@
     string_output_set(sov, g_strdup_printf("%f", *obj));
 }
 
+static void
+start_list(Visitor *v, const char *name, Error **errp)
+{
+    StringOutputVisitor *sov = DO_UPCAST(StringOutputVisitor, visitor, v);
+
+    /* we can't traverse a list in a list */
+    assert(sov->list_mode == LM_NONE);
+    sov->list_mode = LM_STARTED;
+    sov->head = true;
+}
+
+static GenericList *
+next_list(Visitor *v, GenericList **list, Error **errp)
+{
+    StringOutputVisitor *sov = DO_UPCAST(StringOutputVisitor, visitor, v);
+    GenericList *ret = NULL;
+    if (*list) {
+        if (sov->head) {
+            ret = *list;
+        } else {
+            ret = (*list)->next;
+        }
+
+        if (sov->head) {
+            if (ret && ret->next == NULL) {
+                sov->list_mode = LM_NONE;
+            }
+            sov->head = false;
+        } else {
+            if (ret && ret->next == NULL) {
+                sov->list_mode = LM_END;
+            }
+        }
+    }
+
+    return ret;
+}
+
+static void
+end_list(Visitor *v, Error **errp)
+{
+    StringOutputVisitor *sov = DO_UPCAST(StringOutputVisitor, visitor, v);
+
+    assert(sov->list_mode == LM_STARTED ||
+           sov->list_mode == LM_END ||
+           sov->list_mode == LM_NONE ||
+           sov->list_mode == LM_IN_PROGRESS);
+    sov->list_mode = LM_NONE;
+    sov->head = true;
+
+}
+
 char *string_output_get_string(StringOutputVisitor *sov)
 {
-    char *string = sov->string;
+    char *string = g_string_free(sov->string, false);
     sov->string = NULL;
     return string;
 }
@@ -117,7 +318,11 @@
 
 void string_output_visitor_cleanup(StringOutputVisitor *sov)
 {
-    g_free(sov->string);
+    if (sov->string) {
+        g_string_free(sov->string, true);
+    }
+
+    g_list_free_full(sov->ranges, g_free);
     g_free(sov);
 }
 
@@ -127,6 +332,7 @@
 
     v = g_malloc0(sizeof(*v));
 
+    v->string = g_string_new(NULL);
     v->human = human;
     v->visitor.type_enum = output_type_enum;
     v->visitor.type_int = print_type_int;
@@ -134,6 +340,9 @@
     v->visitor.type_bool = print_type_bool;
     v->visitor.type_str = print_type_str;
     v->visitor.type_number = print_type_number;
+    v->visitor.start_list = start_list;
+    v->visitor.next_list = next_list;
+    v->visitor.end_list = end_list;
 
     return v;
 }