2 This source code was extracted from the Q8 package created and
3 placed in the PUBLIC DOMAIN by Doug Gwyn <gwyn@arl.mil>
4 last edit: 1999/11/05 gwyn@arl.mil
6 Implements subclause 7.8.2 of ISO/IEC 9899:1999 (E).
8 This particular implementation requires the matching <inttypes.h>.
9 It also assumes that character codes for A..Z and a..z are in
10 contiguous ascending order; this is true for ASCII but not EBCDIC.
19 /* convert digit character to number, in any base */
20 #define ToNumber(c) (isdigit(c) ? (c) - '0' : \
21 isupper(c) ? (c) - 'A' + 10 : \
22 islower(c) ? (c) - 'a' + 10 : \
23 -1 /* "invalid" flag */ \
25 /* validate converted digit character for specific base */
26 #define valid(n, b) ((n) >= 0 && (n) < (b))
29 strtoimax(nptr, endptr, base)
30 register const char * __restrict__ nptr;
31 char ** __restrict__ endptr;
34 register uintmax_t accum; /* accumulates converted value */
35 register int n; /* numeral from digit character */
36 int minus; /* set iff minus sign seen */
37 int toobig; /* set iff value overflows */
40 *endptr = (char *)nptr; /* in case no conversion's performed */
42 if ( base < 0 || base == 1 || base > 36 )
45 return 0; /* unspecified behavior */
48 /* skip initial, possibly empty sequence of white-space characters */
50 while ( isspace(*nptr) )
53 /* process subject sequence: */
56 if ( (minus = *nptr == '-') || *nptr == '+' )
61 if ( nptr[1] == 'X' || nptr[1] == 'x' )
69 /* optional "0x" or "0X" for base 16 */
71 if ( base == 16 && *nptr == '0' && (nptr[1] == 'X' || nptr[1] == 'x') )
72 nptr += 2; /* skip past this prefix */
74 /* check whether there is at least one valid digit */
79 if ( !valid(n, base) )
80 return 0; /* subject seq. not of expected form */
84 for ( toobig = 0; n = ToNumber(*nptr), valid(n, base); ++nptr )
85 if ( accum > (uintmax_t)(INTMAX_MAX / base + 2) ) /* major wrap-around */
86 toobig = 1; /* but keep scanning */
88 accum = base * accum + n;
91 *endptr = (char *)nptr; /* points to first not-valid-digit */
95 if ( accum > (uintmax_t)INTMAX_MAX + 1 )
99 if ( accum > (uintmax_t)INTMAX_MAX )
105 return minus ? INTMAX_MIN : INTMAX_MAX;
108 return (intmax_t)(minus ? -accum : accum);
111 long long __attribute__ ((alias ("strtoimax")))
112 strtoll (const char* __restrict__ nptr, char ** __restrict__ endptr, int base);