+++ /dev/null
-/*
- * strtoul.c --
- *
- * Source code for the "strtoul" library procedure.
- *
- * Copyright (c) 1988 The Regents of the University of California.
- * Copyright (c) 1994 Sun Microsystems, Inc.
- *
- * See the file "license.terms" for information on usage and redistribution of
- * this file, and for a DISCLAIMER OF ALL WARRANTIES.
- */
-
-#include "tclInt.h"
-
-/*
- * The table below is used to convert from ASCII digits to a numerical
- * equivalent. It maps from '0' through 'z' to integers (100 for non-digit
- * characters).
- */
-
-static const char cvtIn[] = {
- 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, /* '0' - '9' */
- 100, 100, 100, 100, 100, 100, 100, /* punctuation */
- 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, /* 'A' - 'Z' */
- 20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
- 30, 31, 32, 33, 34, 35,
- 100, 100, 100, 100, 100, 100, /* punctuation */
- 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, /* 'a' - 'z' */
- 20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
- 30, 31, 32, 33, 34, 35};
-\f
-/*
- *----------------------------------------------------------------------
- *
- * strtoul --
- *
- * Convert an ASCII string into an integer.
- *
- * Results:
- * The return value is the integer equivalent of string. If endPtr is
- * non-NULL, then *endPtr is filled in with the character after the last
- * one that was part of the integer. If string doesn't contain a valid
- * integer value, then zero is returned and *endPtr is set to string.
- *
- * Side effects:
- * None.
- *
- *----------------------------------------------------------------------
- */
-
-unsigned long int
-strtoul(
- 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. */
- char **endPtr, /* Where to store address of terminating
- * character, or NULL. */
- int base) /* Base for conversion. Must be less than 37.
- * If 0, then the base is chosen from the
- * leading characters of string: "0x" means
- * hex, "0" means octal, anything else means
- * decimal. */
-{
- 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.
- */
-
- p = string;
- while (isspace(UCHAR(*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 of the
- * string.
- */
-
- if (base == 0) {
- if (*p == '0') {
- p += 1;
- if ((*p == 'x') || (*p == 'X')) {
- p += 1;
- base = 16;
- } else {
- /*
- * Must set anyDigits here, otherwise "0" produces a "no
- * digits" error.
- */
-
- anyDigits = 1;
- base = 8;
- }
- } else {
- base = 10;
- }
- } else if (base == 16) {
- /*
- * Skip a leading "0x" from hex numbers.
- */
-
- if ((p[0] == '0') && ((p[1] == 'x') || (p[1] == 'X'))) {
- p += 2;
- }
- }
-
- /*
- * Sorry this code is so messy, but speed seems important. Do different
- * things for base 8, 10, 16, and other.
- */
-
- if (base == 8) {
- unsigned long maxres = ULONG_MAX >> 3;
-
- for ( ; ; p += 1) {
- digit = *p - '0';
- if (digit > 7) {
- break;
- }
- 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;
- }
- 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')) {
- break;
- }
- digit = cvtIn[digit];
- if (digit > 15) {
- break;
- }
- 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')) {
- break;
- }
- digit = cvtIn[digit];
- if (digit >= ( (unsigned) base )) {
- break;
- }
- if (result > maxres) { overflow = 1; }
- result *= base;
- if (digit > (ULONG_MAX - result)) { overflow = 1; }
- result += digit;
- anyDigits = 1;
- }
- }
-
- /*
- * See if there were any digits at all.
- */
-
- if (!anyDigits) {
- p = string;
- }
-
- if (endPtr != 0) {
- /* unsafe, but required by the strtoul prototype */
- *endPtr = (char *) p;
- }
-
- if (overflow) {
- errno = ERANGE;
- return ULONG_MAX;
- }
- if (negative) {
- return -result;
- }
- return result;
-}
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