static void _stp_stack_print_fallback(unsigned long stack, int verbose, int levels)
{
unsigned long addr;
while (levels && stack & (THREAD_SIZE - 1)) {
if (unlikely(_stp_read_address(addr, (unsigned long *)stack, KERNEL_DS))) {
/* cannot access stack. give up. */
return;
}
_stp_print_addr(addr, verbose | _STP_SYM_INEXACT, NULL);
levels--;
stack++;
}
}
/** Return a printable text string.
*
* Takes a string, and any ASCII characters that are not printable are
* replaced by the corresponding escape sequence in the returned
* string.
*
* @param outstr Output string pointer
* @param in Input string pointer
* @param inlen Maximum length of string to read not including terminating 0.
* @param outlen Maximum length of string to return not including terminating 0.
* 0 means MAXSTRINGLEN.
* @param quoted Put double quotes around the string. If input string is truncated
* in will have "..." after the second quote.
* @param user Set this to indicate the input string pointer is a userspace pointer.
*/
static int _stp_text_str(char *outstr, const char *in, int inlen, int outlen,
int quoted, int user)
{
char c = '\0', *out = outstr;
if (inlen <= 0 || inlen > MAXSTRINGLEN-1)
inlen = MAXSTRINGLEN-1;
if (outlen <= 0 || outlen > MAXSTRINGLEN-1)
outlen = MAXSTRINGLEN-1;
if (quoted) {
outlen = max(outlen, 5) - 2;
*out++ = '"';
}
if (_stp_read_address(c, in, (user ? USER_DS : KERNEL_DS)))
goto bad;
while (c && inlen > 0 && outlen > 0) {
int num = 1;
if (isprint(c) && isascii(c)
&& c != '"' && c != '\\') /* quoteworthy characters */
*out++ = c;
else {
switch (c) {
case '\a':
case '\b':
case '\f':
case '\n':
case '\r':
case '\t':
case '\v':
case '"':
case '\\':
num = 2;
break;
default:
num = 4;
break;
}
if (outlen < num)
break;
*out++ = '\\';
switch (c) {
case '\a':
*out++ = 'a';
break;
case '\b':
*out++ = 'b';
break;
case '\f':
*out++ = 'f';
break;
case '\n':
*out++ = 'n';
break;
case '\r':
*out++ = 'r';
break;
case '\t':
*out++ = 't';
break;
case '\v':
*out++ = 'v';
break;
case '"':
*out++ = '"';
break;
case '\\':
*out++ = '\\';
break;
default: /* output octal representation */
*out++ = to_oct_digit((c >> 6) & 03);
*out++ = to_oct_digit((c >> 3) & 07);
*out++ = to_oct_digit(c & 07);
break;
}
}
outlen -= num;
inlen--;
in++;
if (_stp_read_address(c, in, (user ? USER_DS : KERNEL_DS)))
goto bad;
}
if (quoted) {
if (c && inlen > 0) {
out = out - 3 + outlen;
*out++ = '"';
*out++ = '.';
*out++ = '.';
*out++ = '.';
} else
*out++ = '"';
}
*out = '\0';
return 0;
bad:
strlcpy (outstr, "<unknown>", outlen);
return -1; // PR15044
}