[libvirt] [PATCHv2 04/13] virbuf: add auto-indentation support

[Hai Dong Li]

This email is just for your attention. I'm relatively new to work in a 
community, so I didn't pay much attention to the readability of the 
comments last email. It seems comments lie in a large patch like this is 
easily to be omitted. So I cut the codes, leave codes associated with 
the comments.
> Rather than having to adjust all callers in a chain to deal with
> indentation, it is nicer to have virBuffer do auto-indentation.
>
> * src/util/buf.h (_virBuffer): Increase size.
> (virBufferAdjustIndent, virBufferGetIndent): New prototypes.
> * src/libvirt_private.syms (buf.h): Export new functions.
> * src/util/buf.c (virBufferAdjustIndent, virBufferGetIndent): New
> functions.
> (virBufferSetError, virBufferAdd, virBufferAddChar)
> (virBufferVasprintf, virBufferStrcat, virBufferURIEncodeString):
> Implement auto-indentation.
> * tests/virbuftest.c (testBufAutoIndent): Test it.
> (testBufInfiniteLoop): Don't rely on internals.
> Idea by Daniel P. Berrange.
> ---
>   src/libvirt_private.syms |    2 +
>   src/util/buf.c           |  138 ++++++++++++++++++++++++++++-----------------
>   src/util/buf.h           |   12 +++-
>   tests/virbuftest.c       |   85 +++++++++++++++++++++++++---
>   4 files changed, 172 insertions(+), 65 deletions(-)
>
> diff --git a/tests/virbuftest.c b/tests/virbuftest.c
> index 01db313..2f94e1c 100644
> --- a/tests/virbuftest.c
> +++ b/tests/virbuftest.c
>
>
> @@ -63,6 +58,77 @@ out:
>       return ret;
>   }
>
> +static int testBufAutoIndent(const void *data ATTRIBUTE_UNUSED)
> +{
> +    virBuffer bufinit = VIR_BUFFER_INITIALIZER;
> +    virBufferPtr buf =&bufinit;
> +    const char expected[] =
> +        "  1\n  2\n  3\n  4\n  5\n  6\n  7\n&\n  8\n  9\n";
> +    char *result = NULL;
> +    int ret = 0;
> +
> +    if (virBufferGetIndent(buf, false) != 0 ||
> +        virBufferGetIndent(buf, true) != 0) {
> +        TEST_ERROR("Wrong indentation");
> +        ret = -1;
> +    }
> +    virBufferAdjustIndent(buf, 3);
> +    if (virBufferGetIndent(buf, false) != 3 ||
> +        virBufferGetIndent(buf, true) != 3 ||
> +        virBufferError(buf)) {
> +        TEST_ERROR("Wrong indentation");
> +        ret = -1;
> +    }
> +    virBufferAdjustIndent(buf, -2);
> +    if (virBufferGetIndent(buf, false) != 1 ||
> +        virBufferGetIndent(buf, true) != 1 ||
> +        virBufferError(buf)) {
> +        TEST_ERROR("Wrong indentation");
> +        ret = -1;
> +    }
So now buf->indent is 1. Go to the next step, the indent is given -2 
again, see what will happen.
  if virBufferAdjustIndent failed to check the indent overflow, the 
buf->indent will be -1,too, so it may avoid the check 
(virBufferGetIndent(buf, false) != -1) and (virBufferGetIndent(buf, 
true) != -1).
> +    virBufferAdjustIndent(buf, -2);
So I think -3 may be better.
> +    if (virBufferGetIndent(buf, false) != -1 ||
> +        virBufferGetIndent(buf, true) != -1 ||
> +        virBufferError(buf) != -1) {
> +        TEST_ERROR("Usage error not flagged");
> +        ret = -1;
> +    }
> +    virBufferFreeAndReset(buf);
> +    if (virBufferGetIndent(buf, false) != 0 ||
> +        virBufferGetIndent(buf, true) != 0 ||
> +        virBufferError(buf)) {
> +        TEST_ERROR("Reset didn't clear indentation");
> +        ret = -1;
> +    }
> +    virBufferAdjustIndent(buf, 2);
> +    virBufferAddLit(buf, "1");
> +    if (virBufferGetIndent(buf, false) != 2 ||
> +        virBufferGetIndent(buf, true) != 0) {
> +        TEST_ERROR("Wrong indentation");
> +        ret = -1;
> +    }
> +    virBufferAddLit(buf, "\n");
> +    virBufferAdd(buf, "" "2\n", -1); /* Extra "" appeases syntax-check */
> +    virBufferAddChar(buf, '3');
> +    virBufferAddChar(buf, '\n');
> +    virBufferAsprintf(buf, "%d", 4);
> +    virBufferAsprintf(buf, "%c", '\n');
> +    virBufferStrcat(buf, "5", "\n", "6\n", NULL);
> +    virBufferEscapeString(buf, "%s\n", "7");
> +    virBufferEscapeString(buf, "%s\n", "&");
> +    virBufferEscapeSexpr(buf, "%s", "8\n");
> +    virBufferURIEncodeString(buf, "9");
> +    virBufferAddChar(buf, '\n');
> +
> +    result = virBufferContentAndReset(buf);
> +    if (!result || STRNEQ(result, expected)) {
> +        virtTestDifference(stderr, expected, result);
> +        ret = -1;
> +    }
> +    VIR_FREE(result);
> +    return ret;
> +}
> +
>   static int
>   mymain(void)
>   {
>