Re: [Qemu-devel] [PATCH v3 31/34] qapi: make string output visitor parse int list

[Paolo Bonzini <pbonzini@redhat.com>]

Il 26/03/2014 11:37, hutao@cn.fujitsu.com ha scritto:
> Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>

Just a small comment below.

> ---
>  qapi/string-output-visitor.c       | 236 +++++++++++++++++++++++++++++++++++--
>  tests/test-string-output-visitor.c |  35 ++++++
>  2 files changed, 260 insertions(+), 11 deletions(-)
> 
> diff --git a/qapi/string-output-visitor.c b/qapi/string-output-visitor.c
> index fb1d2e8..edfc0a4 100644
> --- a/qapi/string-output-visitor.c
> +++ b/qapi/string-output-visitor.c
> @@ -16,32 +16,177 @@
>  #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;
> +    SignedRangeList *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_list_add(sov->ranges, a, 1);
> +}
> +
> +static void string_output_append_range(StringOutputVisitor *sov,
> +                                       int64_t s, int64_t e)
> +{
> +    range_list_add(sov->ranges, s, e);
>  }
>  
>  static void print_type_int(Visitor *v, int64_t *obj, const char *name,
>                             Error **errp)
>  {
>      StringOutputVisitor *sov = DO_UPCAST(StringOutputVisitor, visitor, v);
> -    char *out;
> +    SignedRange *r;
>  
> -    if (sov->human) {
> -        out = g_strdup_printf("%lld (%#llx)", (long long) *obj, (long long) *obj);
> -    } else {
> -        out = g_strdup_printf("%lld", (long long) *obj);
> +    if (!sov->ranges) {
> +        sov->ranges = g_malloc0(sizeof(*sov->ranges));
> +        QTAILQ_INIT(sov->ranges);
> +    }
> +
> +    switch (sov->list_mode) {
> +    case LM_NONE:
> +        string_output_append(sov, *obj);
> +        goto format_string;
> +        break;
> +

No need for the goto if...

> +    case LM_STARTED:
> +        sov->range_start.s = *obj;
> +        sov->range_end.s = *obj;
> +        sov->list_mode = LM_IN_PROGRESS;
> +        break;

... you have "return;" here

> +    case LM_IN_PROGRESS:
> +        if (sov->range_end.s + 1 == *obj) {
> +            sov->range_end.s++;
> +            break;

    (unnecessary break)

> +        } 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 + 1);
> +            }
> +
> +            sov->range_start.s = *obj;
> +            sov->range_end.s = *obj;
> +        }
> +        break;

... and "return;" here...

> +    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 -
> +                                       sov->range_start.s + 1);
> +        } 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 + 1);
> +            }
> +            string_output_append(sov, *obj);
> +        }

... and "break;" here" and move the formatting code outside the "switch".

> +format_string:
> +        QTAILQ_FOREACH(r, sov->ranges, entry) {
> +            if (r->length > 1) {
> +                g_string_append_printf(sov->string, "%" PRId64 "-%" PRId64,
> +                                       r->start,
> +                                       s_range_end(r->start, r->length));
> +            } else {
> +                g_string_append_printf(sov->string, "%" PRId64,
> +                                       r->start);
> +            }
> +            if (r->entry.tqe_next) {
> +                g_string_append(sov->string, ",");
> +            }
> +        }
> +
> +        if (sov->human) {
> +            g_string_append(sov->string, " (");
> +            QTAILQ_FOREACH(r, sov->ranges, entry) {
> +                if (r->length > 1) {
> +                    g_string_append_printf(sov->string, "%" PRIx64 "-%" PRIx64,
> +                                           r->start,
> +                                           s_range_end(r->start, r->length));
> +                } else {
> +                    g_string_append_printf(sov->string, "%" PRIx64,
> +                                           r->start);
> +                }
> +                if (r->entry.tqe_next) {
> +                    g_string_append(sov->string, ",");
> +                }
> +            }
> +            g_string_append(sov->string, ")");
> +        }
> +
> +        break;
> +
> +    default:
> +        abort();
>      }
> -    string_output_set(sov, out);
>  }
>  
>  static void print_type_size(Visitor *v, uint64_t *obj, const char *name,
> @@ -103,9 +248,61 @@ static void print_type_number(Visitor *v, double *obj, const char *name,
>      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 +314,20 @@ Visitor *string_output_get_visitor(StringOutputVisitor *sov)
>  
>  void string_output_visitor_cleanup(StringOutputVisitor *sov)
>  {
> -    g_free(sov->string);
> +    SignedRange *r, *next;
> +
> +    if (sov->string) {
> +        g_string_free(sov->string, true);
> +    }
> +
> +    if (sov->ranges) {
> +        QTAILQ_FOREACH_SAFE(r, sov->ranges, entry, next) {
> +            QTAILQ_REMOVE(sov->ranges, r, entry);
> +            s_range_free(r);
> +        }
> +        g_free(sov->ranges);
> +    }
> +
>      g_free(sov);
>  }
>  
> @@ -127,6 +337,7 @@ StringOutputVisitor *string_output_visitor_new(bool human)
>  
>      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 +345,9 @@ StringOutputVisitor *string_output_visitor_new(bool human)
>      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;
>  }
> diff --git a/tests/test-string-output-visitor.c b/tests/test-string-output-visitor.c
> index 22363d1..a460377 100644
> --- a/tests/test-string-output-visitor.c
> +++ b/tests/test-string-output-visitor.c
> @@ -57,6 +57,39 @@ static void test_visitor_out_int(TestOutputVisitorData *data,
>      g_free(str);
>  }
>  
> +static void test_visitor_out_intList(TestOutputVisitorData *data,
> +                                     const void *unused)
> +{
> +    int64_t value[] = {-10, -7, -2, -1, 0, 1, 9, 10, 16, 15, 14,
> +        3, 4, 5, 6, 11, 12, 13, 21, 22, INT64_MAX - 1, INT64_MAX};
> +    intList *list = NULL, **tmp = &list;
> +    int i;
> +    Error *errp = NULL;
> +    char *str;
> +
> +    for (i = 0; i < sizeof(value) / sizeof(value[0]); i++) {
> +        *tmp = g_malloc0(sizeof(**tmp));
> +        (*tmp)->value = value[i];
> +        tmp = &(*tmp)->next;
> +    }
> +
> +    visit_type_intList(data->ov, &list, NULL, &errp);
> +    g_assert(error_is_set(&errp) == 0);
> +
> +    str = string_output_get_string(data->sov);
> +    g_assert(str != NULL);
> +    g_assert_cmpstr(str, ==,
> +        "-10,-7,-2-1,3-6,9-16,21-22,9223372036854775806-9223372036854775807");
> +    g_free(str);
> +#if 0
> +    while (list) {
> +        tmp2 = list->next;
> +        g_free(list);
> +        list = tmp2;
> +    }
> +#endif
> +}
> +
>  static void test_visitor_out_bool(TestOutputVisitorData *data,
>                                    const void *unused)
>  {
> @@ -182,6 +215,8 @@ int main(int argc, char **argv)
>                              &out_visitor_data, test_visitor_out_enum);
>      output_visitor_test_add("/string-visitor/output/enum-errors",
>                              &out_visitor_data, test_visitor_out_enum_errors);
> +    output_visitor_test_add("/string-visitor/output/intList",
> +                            &out_visitor_data, test_visitor_out_intList);
>  
>      g_test_run();
>  
>