/*
* Very simple implementation of strtoul() for gawk,
* for old systems. Descriptive prose from the Linux man page.
*
* May 2004
*/
/* #define TEST 1 */
#ifdef TEST
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <errno.h>
#include <limits.h>
#define strtoul mystrtoul
#endif
#ifndef ULONG_MAX
#define ULONG_MAX (~ 0UL)
#endif
unsigned long int
strtoul(nptr, endptr, base)
const char *nptr;
char **endptr;
int base;
{
static char lower[] = "abcdefghijklmnopqrstuvwxyz";
unsigned long result = 0UL;
char *nptr_orig = (char *) nptr;
bool neg = false;
char *cp, c;
int val;
bool sawdigs = false;
/*
* The strtoul() function converts the initial part of the
* string in nptr to an unsigned long integer value according
* to the given base, which must be between 2 and 36 inclusive,
* or be the special value 0.
*/
if ((base != 0 && (base < 2 || base > 36)) || nptr == NULL) {
if (endptr != NULL)
*endptr = nptr_orig;
errno = EINVAL;
return 0;
}
/*
* The string must [sic] begin with an arbitrary amount of white space
* (as determined by isspace(3)) followed by a single optional
* `+' or `-' sign.
*/
while (isspace(*nptr))
nptr++;
if (*nptr == '+')
nptr++;
else if (*nptr == '-') {
nptr++;
neg = true;
}
/*
* If base is zero or 16, the string may then include a `0x' prefix,
* and the number will be read in base 16; otherwise, a zero base is
* taken as 10 (decimal) unless the next character is `0', in which
* case it is taken as 8 (octal).
*/
if ((base == 0 || base == 16)
&& nptr[0] == '0'
&& (nptr[1] == 'x' || nptr[1] == 'X')) {
base = 16; /* force it */
nptr += 2; /* skip 0x */
} else if ((base == 0 || base == 8) && nptr[0] == '0') {
base = 8;
nptr++;
} else if (base == 0)
base = 10;
/*
* The remainder of the string is converted to an unsigned long int
* value in the obvious manner, stopping at the first character
* which is not a valid digit in the given base. (In bases above 10,
* the letter `A' in either upper or lower case represents 10,
* `B' represents 11, and so forth, with `Z' representing 35.)
*/
for (; *nptr != '\0'; nptr++) {
c = *nptr;
#if defined(HAVE_LOCALE_H)
if (base == 10
&& loc.thousands_sep != NULL
&& loc.thousands_sep[0] != '\0'
&& c == loc.thousands_sep[0])
continue;
#endif
switch (c) {
case '0': case '1': case '2':
case '3': case '4': case '5':
case '6': case '7': case '8':
case '9':
val = c - '0';
if (val >= base) /* even base 2 allowed ... */
goto out;
result *= base;
result += val;
sawdigs = true;
break;
case 'A': case 'B': case 'C': case 'D': case 'E':
case 'F': case 'G': case 'H': case 'I': case 'J':
case 'K': case 'L': case 'M': case 'N': case 'O':
case 'P': case 'Q': case 'R': case 'S': case 'T':
case 'U': case 'V': case 'W': case 'X': case 'Y':
case 'Z':
c += 'a' - 'A'; /* downcase */
/* fall through */
case 'a': case 'b': case 'c': case 'd': case 'e':
case 'f': case 'g': case 'h': case 'i': case 'j':
case 'k': case 'l': case 'm': case 'n': case 'o':
case 'p': case 'q': case 'r': case 's': case 't':
case 'u': case 'v': case 'w': case 'x': case 'y':
case 'z':
cp = strchr(lower, c);
val = cp - lower;
val += 10; /* 'a' == 10 */
if (val >= base)
goto out;
result *= base;
result += val;
sawdigs = true;
break;
default:
goto out;
}
}
out:
/*
* If endptr is not NULL, strtoul() stores the address of the
* first invalid character in *endptr. If there were no digits
* at all, strtoul() stores the original value of nptr in *endptr
* (and returns 0). In particular, if *nptr is not `\0' but
* **endptr is `\0' on return, the entire string is valid.
*/
if (endptr != NULL) {
if (! sawdigs) {
*endptr = nptr_orig;
return 0;
} else
*endptr = (char *) nptr;
}
/*
* RETURN VALUE
* The strtoul() function returns either the result of the
* conversion or, if there was a leading minus sign, the
* negation of the result of the conversion, unless the original
* (non-negated) value would overflow; in the latter case,
* strtoul() returns ULONG_MAX and sets the global variable errno
* to ERANGE.
*/
/*
* ADR: This computation is probably bogus. If it's a
* problem, upgrade to a modern system.
*/
if (neg && result == ULONG_MAX) {
errno = ERANGE;
return ULONG_MAX;
} else if (neg)
result = -result;
return result;
}
#ifdef TEST
#undef strtoul
int main(void)
{
char *endptr;
unsigned long res1, res2;
res1 = strtoul("0xdeadBeeF", & endptr, 0),
res2 = mystrtoul("0xdeadBeeF", & endptr, 0),
printf("(real,my)strtoul(\"0xdeadBeeF\", & endptr, 0) is %lu, %lu *endptr = %d\n",
res1, res2, *endptr);
res1 = strtoul("0101101", & endptr, 2),
res2 = mystrtoul("0101101", & endptr, 2),
printf("(real,my)strtoul(\"0101101\", & endptr, 2) is %lu, %lu *endptr = %d\n",
res1, res2, *endptr);
res1 = strtoul("01011012", & endptr, 2),
res2 = mystrtoul("01011012", & endptr, 2),
printf("(real,my)strtoul(\"01011012\", & endptr, 2) is %lu, %lu *endptr = %d\n",
res1, res2, *endptr);
res1 = strtoul(" +42a", & endptr, 0),
res2 = mystrtoul(" +42a", & endptr, 0),
printf("(real,my)strtoul(\" +42a\", & endptr, 0) is %lu, %lu *endptr = %d\n",
res1, res2, *endptr);
res1 = strtoul("0377", & endptr, 0),
res2 = mystrtoul("0377", & endptr, 0),
printf("(real,my)strtoul(\"0377\", & endptr, 0) is %lu, %lu *endptr = %d\n",
res1, res2, *endptr);
res1 = strtoul("Z", & endptr, 36),
res2 = mystrtoul("Z", & endptr, 36),
printf("(real,my)strtoul(\"Z\", & endptr, 36) is %lu, %lu *endptr = %d\n",
res1, res2, *endptr);
res1 = strtoul("qZ*", & endptr, 36),
res2 = mystrtoul("qZ*", & endptr, 36),
printf("(real,my)strtoul(\"qZ*\", & endptr, 36) is %lu, %lu *endptr = %d\n",
res1, res2, *endptr);
}
#endif