Re: gawk number to string bug

[Andrew J. Schorr]

On Fri, Dec 23, 2005 at 03:57:38PM -0500, Andrew J. Schorr wrote:
> If we can agree on this approach, then the next step is to use
> snprintf("%.0f") to implement "%d" formatting (using a 2nd dynamically
> growing buffer for the initial snprintf rendering)...

OK, I went ahead and did it.  Here's the full patch to fix the
buffer overflow and implement "%.0f" formatting for "%d".
And here's the output of the test case on linux opteron:

   $ ./gawk --lint 'BEGIN { x=2^60; for(i=60;i<=65;i++) { printf "2^%d= %s %d 
%g\n",i,x,x,x; x*=2}}'
   2^60= 1152921504606846976 1152921504606846976 1.15292e+18
   2^61= 2305843009213693952 2305843009213693952 2.30584e+18
   2^62= 4611686018427387904 4611686018427387904 4.61169e+18
   2^63= 9.22337e+18 9223372036854775808 9.22337e+18
   2^64= 1.84467e+19 18446744073709551616 1.84467e+19
   2^65= 3.68935e+19 36893488147419103232 3.68935e+19

And on a 32-bit x86 linux box:

   $ ./gawk --lint 'BEGIN { x=2^60; for(i=60;i<=65;i++) { printf "2^%d= %s %d 
%g\n",i,x,x,x; x*=2}}'
   2^60= 1.15292e+18 1152921504606846976 1.15292e+18
   2^61= 2.30584e+18 2305843009213693952 2.30584e+18
   2^62= 4.61169e+18 4611686018427387904 4.61169e+18
   2^63= 9.22337e+18 9223372036854775808 9.22337e+18
   2^64= 1.84467e+19 18446744073709551616 1.84467e+19
   2^65= 3.68935e+19 36893488147419103232 3.68935e+19

It passes 'make check' on both platforms.  Comments?

Note that this patch doesn't fix possible problems with "%o" or other
non-base-10 formatting.

Regards,
Andy

format_tree.patch
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