Oh, I was playing about with this earlier, but didn't get all that far:
I go this far in svn.c (has breakpoint marker in it)
[[[
int
main(int argc, char **argv)
{
apr_pool_t *pool;
int exit_code = EXIT_SUCCESS;
svn_error_t *err;
const char **argv_org;
/* Initialize the app. */
if (svn_cmdline_init("svn", stderr) != EXIT_SUCCESS)
return EXIT_FAILURE;
/* Create our top-level pool. Use a separate mutexless allocator,
* given this application is single threaded.
*/
pool = apr_allocator_owner_get(svn_pool_create_allocator(FALSE));
{
int i;
argv_org = apr_palloc(pool, sizeof(argv));
B for(i = 0; i < argc; i++)
{
argv_org[i] = apr_pstrdup(pool, argv[i]);
if (i > 2 && !strcmp(argv[i-1],"--password"))
{
argv[i-1] = "#####\0";
}
if (i > 2 && !strcmp(argv[i-1],"--username"))
{
argv[i-1] = "#####\0";
}
}
}
]]]
it compiles and runs and in gdb the vars do change, but the compiler isn't
happy:
subversion/svn/svn.c: In function 'main':
subversion/svn/svn.c:3048:23: warning: assignment discards 'const'
qualifier from pointer target type [enable\
d by default]
argv[i-1] = "#####\0";
^
subversion/svn/svn.c:3052:23: warning: assignment discards 'const'
qualifier from pointer target type [enable\
d by default]
argv[i-1] = "#####\0";
At breakpoint B, gdb gives me:
(gdb) p argv
$1 = (char **) 0x7fffffffe468
(gdb) p argv[1]
$2 = 0x7fffffffe81e "svn"
(gdb) p argv[2]
$3 = 0x7fffffffe822 "help"
(gdb) p argv[3]
$4 = 0x4438b3 "#####"
(gdb)
So it def. does change it.
On Fri, Jul 4, 2014 at 12:40 AM, Ben Reser <[email protected]> wrote:
> On 7/3/14 4:23 PM, Gabriela Gibson wrote:
> > Could that be because of the libtool svn-lt script that sits in the
> middle?
> > Because in gdb it does change, but not in ps.
>
> No because I wasn't even doing anything with Subversion yet let alone
> libtool.
> It was just a very basic C program with nothing more than a main. It's
> probably because the argv array belongs to the process itself and then it
> points to memory that the kernel owns (or at least watches). I'm not sure
> on
> all the details of how the kernel starts the binary and passes in the
> arguments.
>
> I've attached the example I was working with that didn't make it to this
> list
> already.
>
>
--
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