Use signed long for FPDF_GetNamedDest buffer length.

Use signed long for FPDF_GetNamedDest buffer length.

Need to have return value -1 indicating insufficient buffer.

R=tsepez@chromium.org

Committed: https://pdfium.googlesource.com/pdfium/+/dc43b322915c5256a5a9458e6b8cd28bcecf91ae

[Bo Xu, 2015-01-21 21:43:50]

bo_xu@foxitsoftware.com changed reviewers:
+ tsepez@chromium.org

[Bo Xu, 2015-01-21 21:43:51]

Hi Tom, please review this.

[Tom Sepez, 2015-01-21 21:51:29]

lgtm

https://codereview.chromium.org/862163002/diff/1/fpdfsdk/include/fpdfview.h
File fpdfsdk/include/fpdfview.h (right):

https://codereview.chromium.org/862163002/diff/1/fpdfsdk/include/fpdfview.h#n...
fpdfsdk/include/fpdfview.h:629: //			buflen		-	The length of the buffer in byte.
nit: I'd comment this as:
  buflen [in/out]  - Size of the buffer in bytes on input, length of the result
in bytes on output or -1 if the buffer is too small.

https://codereview.chromium.org/862163002/diff/1/fpdfsdk/include/fpdfview.h#n...
fpdfsdk/include/fpdfview.h:631: //			The destination handle of a named
destination, NULL when retrieving the length.
nit: The destination handle of a named destination, or NULL if no named
destination corresponds to |index|, or NULL if no buffer is provided and are
merely querying the length.

https://codereview.chromium.org/862163002/diff/1/fpdfsdk/include/fpdfview.h#n...
fpdfsdk/include/fpdfview.h:636: //			   If buflen is not sufficiently large, it
will be returned as -1.
nit: 
If buflen is not sufficiently large, it will be set to -1 upon return.

[Bo Xu, 2015-01-21 22:00:26]

https://codereview.chromium.org/862163002/diff/1/fpdfsdk/include/fpdfview.h
File fpdfsdk/include/fpdfview.h (right):

https://codereview.chromium.org/862163002/diff/1/fpdfsdk/include/fpdfview.h#n...
fpdfsdk/include/fpdfview.h:631: //			The destination handle of a named
destination, NULL when retrieving the length.
On 2015/01/21 21:51:28, Tom Sepez wrote:
> nit: The destination handle of a named destination, or NULL if no named
> destination corresponds to |index|, or NULL if no buffer is provided and are
> merely querying the length.

Currently we still return destination when querying. If you want, I can change
it to returning NULL.

[Tom Sepez, 2015-01-21 22:10:06]

> Currently we still return destination when querying. If you want, I can change
> it to returning NULL.
No, that's OK.  Just make the comment match the current behaviour.

[Bo Xu, 2015-01-21 22:20:35]

Committed patchset #2 (id:20001) manually as
dc43b322915c5256a5a9458e6b8cd28bcecf91ae (presubmit successful).