Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.programming > #10694

Re: Coding while drunk and stoned take 2. (Yes, I know this is a cross post)

Show all headers | View raw

On Thursday, 27 February 2020 16:55:29 UTC+1, Ben Bacarisse  wrote:
> "Chad Altenburg, Ph.D." <cdalten@gmail.com> writes:
<snip>
> > My gut feeling says this isn't right. But I have no idea how this
> > could be done in one loop.
> 
> Here's a C solution.  It's messy because the natural way to do string
> things in C is to pass an array to take the result.  You then need to
> pass a size so the function does not write out-of-bounds.  But to be
> useful the function should keep going and return the size that's needed
> even when there was no room this time:
> 
> #include <stdio.h>
> 
> size_t zipzap(const char *src, char *dst, size_t n)
> {
>      size_t i = 0;
>      while (*src) {
>           if (i < n)
>                dst[i] = *src;
>           i += 1;
>           if (src[0] == 'z' && src[1] && src[2] == 'p') {
>                if (i < n)
>                     dst[i] = 'p';
>                i += 1;
>                src += 3;
>           }
>           else src += 1;
>      }
>      dst[i <= n ? i : n-1] = 0;
>      return i + 1;
> }
> 
> int main(int argc, char **argv)
> {
>      char z[10];
>      for (int a = 1; a < argc; a++) {
>           size_t required = zipzap(argv[a], z, sizeof z);
>           printf("%s -> %s (%zu)\n", argv[a], z, required);
>      }
> }
> 
> The more "scripty" way -- allocating the result -- looks simpler:
> 
> char *zipzap_str(const char *src)
> {
>      char result[strlen(src) + 1], *dst = result;
>      while (*src) {
>           *dst++ = *src++;
>           if (src[-1] == 'z' && src[0] && src[1] == 'p') {
>                *dst++ = 'p';
>                src += 2;
>           }
>      }
>      *dst++ = 0;
>      char *rp = malloc(dst - result);
>      return rp ? strcpy(rp, result) : 0;
> }

Man, that hurts...

Julio

Back to comp.programming | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Coding while drunk and stoned take 2. (Yes, I know this is a cross post) "Chad Altenburg, Ph.D." <cdalten@gmail.com> - 2020-02-27 06:04 -0800
  Re: Coding while drunk and stoned take 2. (Yes, I know this is a cross post) Julio Di Egidio <julio@diegidio.name> - 2020-02-27 07:24 -0800
  Re: Coding while drunk and stoned take 2. (Yes, I know this is a cross post) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-27 15:55 +0000
    Re: Coding while drunk and stoned take 2. (Yes, I know this is a cross post) Julio Di Egidio <julio@diegidio.name> - 2020-02-27 08:06 -0800
      Re: Coding while drunk and stoned take 2. (Yes, I know this is a cross post) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-27 21:00 +0000
        Re: Coding while drunk and stoned take 2. (Yes, I know this is a cross post) "Chad Altenburg, Ph.D." <cdalten@gmail.com> - 2020-02-27 15:18 -0800
  Re: Coding while drunk and stoned take 2. (Yes, I know this is a cross post) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-27 21:06 +0000

csiph-web