/*
* Document-method: PinkTrace::StringArray.decode
* call-seq:
* PinkTrace::StringArray.decode(pid, arg, index, [[maxlen=-1], [bitness=PinkTrace::Bitness::DEFAULT]]) -> String or nil
*
* This function decodes the member of the string array pointed by the address
* +arg+. The +index+ argument specifies the index of the member in the string
* array.
*
* Note: If the string array member was NULL, this function returns nil.
*/
VALUE
pinkrb_decode_strarray(int argc, VALUE *argv, VALUE mod)
{
bool nil;
pid_t pid;
unsigned bit, ind;
long arg;
int maxlen;
char *str;
VALUE vpid, varg, vind, vmax, vbit, vret;
switch (rb_scan_args(argc, argv, "32", &vpid, &varg, &vind, &vmax, &vbit)) {
case 3:
maxlen = -1;
bit = PINKTRACE_BITNESS_DEFAULT;
break;
case 4:
maxlen = NUM2INT(vmax);
bit = PINKTRACE_BITNESS_DEFAULT;
break;
case 5:
maxlen = NUM2INT(vmax);
bit = FIX2UINT(vbit);
break;
default:
abort();
}
pid = NUM2PIDT(vpid);
arg = NUM2LONG(varg);
ind = FIX2UINT(vind);
if (maxlen < 0) {
/* Use pink_decode_string_array_member_persistent() */
errno = 0;
str = pink_decode_string_array_member_persistent(pid, bit, arg, ind);
if (!str) {
if (errno)
rb_sys_fail("pink_decode_string_array_member_persistent()");
return Qnil;
}
vret = rb_str_new2(str);
free(str);
return vret;
}
/* Use pink_decode_string_array_member() */
str = ALLOC_N(char, maxlen);
if (!pink_decode_string_array_member(pid, bit, arg, ind, str, maxlen, &nil))
rb_sys_fail("pink_decode_string_array_member()");
if (nil) {
free(str);
return Qnil;
}
vret = rb_str_new2(str);
if (str)
free(str);
return vret;
}
/* A very basic decoder for execve(2) system call. */
static void
decode_execve(pid_t pid, pink_bitness_t bitness)
{
bool nil;
unsigned i;
long arg;
char buf[MAX_STRING_LEN];
const char *sep;
if (!pink_decode_string(pid, bitness, 0, buf, MAX_STRING_LEN)) {
perror("pink_decode_string");
return;
}
if (!pink_util_get_arg(pid, bitness, 1, &arg)) {
perror("pink_util_get_arg");
return;
}
printf("execve(\"%s\", [", buf);
for (i = 0, nil = false, sep = "";;sep = ", ") {
if (!pink_decode_string_array_member(pid, bitness, arg, ++i, buf, MAX_STRING_LEN, &nil)) {
perror("pink_decode_string_array_member");
return;
}
printf("%s\"%s\"", sep, buf);
if (nil) {
printf("], envp[])");
break;
}
}
}