diff options
Diffstat (limited to 'compat/strtoul.c')
| -rw-r--r-- | compat/strtoul.c | 57 |
1 files changed, 46 insertions, 11 deletions
diff --git a/compat/strtoul.c b/compat/strtoul.c index e31299d..ddb1682 100644 --- a/compat/strtoul.c +++ b/compat/strtoul.c @@ -9,10 +9,11 @@ * See the file "license.terms" for information on usage and redistribution * of this file, and for a DISCLAIMER OF ALL WARRANTIES. * - * RCS: @(#) $Id: strtoul.c,v 1.3 2002/02/15 23:42:12 kennykb Exp $ + * RCS: @(#) $Id: strtoul.c,v 1.4 2002/02/24 02:53:25 dgp Exp $ */ -#include <ctype.h> +#include "tclInt.h" +#include "tclPort.h" /* * The table below is used to convert from ASCII digits to a @@ -53,7 +54,7 @@ static char cvtIn[] = { unsigned long int strtoul(string, endPtr, base) - char *string; /* String of ASCII digits, possibly + CONST char *string; /* String of ASCII digits, possibly * preceded by white space. For bases * greater than 10, either lower- or * upper-case digits may be used. @@ -67,10 +68,12 @@ strtoul(string, endPtr, base) * else means decimal. */ { - register char *p; + register CONST char *p; register unsigned long int result = 0; register unsigned digit; int anyDigits = 0; + int negative=0; + int overflow=0; /* * Skip any leading blanks. @@ -80,6 +83,14 @@ strtoul(string, endPtr, base) while (isspace(*p)) { p += 1; } + if (*p == '-') { + negative = 1; + p += 1; + } else { + if (*p == '+') { + p += 1; + } + } /* * If no base was provided, pick one from the leading characters @@ -90,7 +101,7 @@ strtoul(string, endPtr, base) { if (*p == '0') { p += 1; - if (*p == 'x') { + if ((*p == 'x') || (*p == 'X')) { p += 1; base = 16; } else { @@ -111,7 +122,7 @@ strtoul(string, endPtr, base) * Skip a leading "0x" from hex numbers. */ - if ((p[0] == '0') && (p[1] == 'x')) { + if ((p[0] == '0') && ((p[1] == 'x') || (p[1] == 'X'))) { p += 2; } } @@ -122,24 +133,33 @@ strtoul(string, endPtr, base) */ if (base == 8) { + unsigned long maxres = ULONG_MAX >> 3; for ( ; ; p += 1) { digit = *p - '0'; if (digit > 7) { break; } - result = (result << 3) + digit; + if (result > maxres) { overflow = 1; } + result = (result << 3); + if (digit > (ULONG_MAX - result)) { overflow = 1; } + result += digit; anyDigits = 1; } } else if (base == 10) { + unsigned long maxres = ULONG_MAX / 10; for ( ; ; p += 1) { digit = *p - '0'; if (digit > 9) { break; } - result = (10*result) + digit; + if (result > maxres) { overflow = 1; } + result *= 10; + if (digit > (ULONG_MAX - result)) { overflow = 1; } + result += digit; anyDigits = 1; } } else if (base == 16) { + unsigned long maxres = ULONG_MAX >> 4; for ( ; ; p += 1) { digit = *p - '0'; if (digit > ('z' - '0')) { @@ -149,10 +169,14 @@ strtoul(string, endPtr, base) if (digit > 15) { break; } - result = (result << 4) + digit; + if (result > maxres) { overflow = 1; } + result = (result << 4); + if (digit > (ULONG_MAX - result)) { overflow = 1; } + result += digit; anyDigits = 1; } } else if ( base >= 2 && base <= 36 ) { + unsigned long maxres = ULONG_MAX / base; for ( ; ; p += 1) { digit = *p - '0'; if (digit > ('z' - '0')) { @@ -162,7 +186,10 @@ strtoul(string, endPtr, base) if (digit >= ( (unsigned) base )) { break; } - result = result*base + digit; + if (result > maxres) { overflow = 1; } + result *= base; + if (digit > (ULONG_MAX - result)) { overflow = 1; } + result += digit; anyDigits = 1; } } @@ -176,8 +203,16 @@ strtoul(string, endPtr, base) } if (endPtr != 0) { - *endPtr = p; + /* unsafe, but required by the strtoul prototype */ + *endPtr = (char *) p; } + if (overflow) { + errno = ERANGE; + return ULONG_MAX; + } + if (negative) { + return -result; + } return result; } |