Re: back into the thread....

[Mark Manning <mark4th@gmail.com>]

disregard, you pasted in the new copy but missed the initial # on the
first include. i also missed that :)

On Tue, Nov 12, 2013 at 5:59 PM, Mark Manning <mark4th@gmail.com> wrote:
> tried to compile your code but all i get is about 400 errors related
> to error unknown type name 'size_t' from stdlib.h.
>
>
>
>
> On Tue, Nov 12, 2013 at 5:47 PM, Sterling Augustine
> <saugustine@google.com> wrote:
>> On Tue, Nov 12, 2013 at 2:42 PM, Sterling Augustine
>> <saugustine@google.com> wrote:
>>> This feature clearly works.
>>>
>>
>> .. This time with a couple of cleanups. The old example definitely
>> works, this just eliminates an extraneous call to malloc and an
>> uninitialized variable.
>>
>> include <stdio.h>
>> #include <stdlib.h>
>> #include <sys/mman.h>
>> #include <string.h>
>> #include <malloc.h>
>>
>> const char bytes[] = { 0x89, 0xf8, 0xc3 };
>> #define EXEC_BYTES sizeof(bytes)
>>
>> typedef int(*function_ptr)(int);
>>
>> int main(int argc, char *argv[])
>> {
>>   int test_val = 5;
>>   int return_val;
>>   function_ptr dst;
>>   if (posix_memalign((void **) &dst, 4096*8, EXEC_BYTES) != 0) {
>>     printf("can't allocate.\n");
>>     exit (-1);
>>   }
>>   if (mprotect(dst, EXEC_BYTES, PROT_READ|PROT_WRITE|PROT_EXEC) != 0) {
>>     printf("can't mprotect\n");
>>     exit (-1);
>>   }
>>
>>   if (argc > 1)
>>     test_val = atoi(argv[1]);
>>
>>   memcpy(dst, bytes, EXEC_BYTES);
>>
>>   return_val = dst(test_val);
>>   printf("return val was %d\n", return_val);
>>   return 0;
>> }
>
>
>
> --
> "When something can be read without effort,
> great effort has gone into its writing."
>
> -- Enrique Jardiel Poncela --



-- 
"When something can be read without effort,
great effort has gone into its writing."

-- Enrique Jardiel Poncela --