Use of "int" for length is troubling

[jasom]

It is possible for allocations to exceed INT_MAX in size, most notably on most 64-bit C implementations.

I think ptrdiff_t is the best signed type available for using this, but may be wrong.

[websnarf]

There is no PTRDIFF_MAX in limits.h, at least not for older compilers. The Better String Library was initially targeted at string manipulation; int was chosen because it seemed like the practical choice on all the compilers I was targeting at the time. These days, you can have strings that exceed 2.1 billion characters, but at this point, I am not sure about calling it a string any more. Keep in mind that the library use negative values to determine if the string is value, or writable. So what I really wanted to use was the type ssize_t as first defined by the BSD header files, but this is not portable to older compilers.

That being said, I can consider a future version of the Better String Library, where the size and length type are settable by some configuration in bstrlib.h .

[mikejsavage]

size_t would be more appropriate, with flags to handle the negative cases. There's also a trick used in the kernel to generate *_MAX definitions:

#define SIZE_MAX ((size_t)~0)
#define SSIZE_MAX ((ssize_t)(~0 >> 1))

See this header for more examples.

[websnarf]

ssize_t is not ANSI C, which is the minimal target for bstrlib.

[mikejsavage]

It was just an example - ideally bstring would use size_t

-----Original Message-----
From: "websnarf" notifications@github.com
Sent: ‎04/‎12/‎2015 07:56 AM
To: "websnarf/bstrlib" bstrlib@noreply.github.com
Cc: "Michael Savage" mikejsavage@gmail.com
Subject: Re: [bstrlib] Use of "int" for length is troubling (#5)

ssize_t is not ANSI C, which is the minimal target for bstrlib.
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[MarcusJohnson91]

Size_t is the best option, and yes, it's supported in C.