android / trusty / external / trusted-firmware-a / 7434b65208175bdf3f44e0e62aaaeabc9c494ee3 / . / lib / libc / strtol.c

/*- | |

* SPDX-License-Identifier: BSD-3-Clause | |

* | |

* Copyright (c) 1990, 1993 | |

* The Regents of the University of California. All rights reserved. | |

* | |

* Copyright (c) 2011 The FreeBSD Foundation | |

* All rights reserved. | |

* Portions of this software were developed by David Chisnall | |

* under sponsorship from the FreeBSD Foundation. | |

* | |

* Redistribution and use in source and binary forms, with or without | |

* modification, are permitted provided that the following conditions | |

* are met: | |

* 1. Redistributions of source code must retain the above copyright | |

* notice, this list of conditions and the following disclaimer. | |

* 2. Redistributions in binary form must reproduce the above copyright | |

* notice, this list of conditions and the following disclaimer in the | |

* documentation and/or other materials provided with the distribution. | |

* 3. Neither the name of the University nor the names of its contributors | |

* may be used to endorse or promote products derived from this software | |

* without specific prior written permission. | |

* | |

* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND | |

* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |

* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |

* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE | |

* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |

* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |

* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |

* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |

* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |

* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |

* SUCH DAMAGE. | |

*/ | |

#include <errno.h> | |

#include <limits.h> | |

#include <stddef.h> | |

#include <stdlib.h> | |

/* | |

* Convert a string to a long integer. | |

* | |

* Assumes that the upper and lower case | |

* alphabets and digits are each contiguous. | |

*/ | |

long strtol(const char *nptr, char **endptr, int base) | |

{ | |

const char *s; | |

unsigned long acc; | |

char c; | |

unsigned long cutoff; | |

int neg, any, cutlim; | |

/* | |

* Skip white space and pick up leading +/- sign if any. | |

* If base is 0, allow 0x for hex and 0 for octal, else | |

* assume decimal; if base is already 16, allow 0x. | |

*/ | |

s = nptr; | |

do { | |

c = *s++; | |

} while (isspace((unsigned char)c)); | |

if (c == '-') { | |

neg = 1; | |

c = *s++; | |

} else { | |

neg = 0; | |

if (c == '+') | |

c = *s++; | |

} | |

if ((base == 0 || base == 16) && | |

c == '0' && (*s == 'x' || *s == 'X') && | |

((s[1] >= '0' && s[1] <= '9') || | |

(s[1] >= 'A' && s[1] <= 'F') || | |

(s[1] >= 'a' && s[1] <= 'f'))) { | |

c = s[1]; | |

s += 2; | |

base = 16; | |

} | |

if (base == 0) | |

base = c == '0' ? 8 : 10; | |

acc = any = 0; | |

/* | |

* Compute the cutoff value between legal numbers and illegal | |

* numbers. That is the largest legal value, divided by the | |

* base. An input number that is greater than this value, if | |

* followed by a legal input character, is too big. One that | |

* is equal to this value may be valid or not; the limit | |

* between valid and invalid numbers is then based on the last | |

* digit. For instance, if the range for longs is | |

* [-2147483648..2147483647] and the input base is 10, | |

* cutoff will be set to 214748364 and cutlim to either | |

* 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated | |

* a value > 214748364, or equal but the next digit is > 7 (or 8), | |

* the number is too big, and we will return a range error. | |

* | |

* Set 'any' if any `digits' consumed; make it negative to indicate | |

* overflow. | |

*/ | |

cutoff = neg ? (unsigned long)-(LONG_MIN + LONG_MAX) + LONG_MAX | |

: LONG_MAX; | |

cutlim = cutoff % base; | |

cutoff /= base; | |

for ( ; ; c = *s++) { | |

if (c >= '0' && c <= '9') | |

c -= '0'; | |

else if (c >= 'A' && c <= 'Z') | |

c -= 'A' - 10; | |

else if (c >= 'a' && c <= 'z') | |

c -= 'a' - 10; | |

else | |

break; | |

if (c >= base) | |

break; | |

if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim)) | |

any = -1; | |

else { | |

any = 1; | |

acc *= base; | |

acc += c; | |

} | |

} | |

if (any < 0) { | |

acc = neg ? LONG_MIN : LONG_MAX; | |

} else if (neg) | |

acc = -acc; | |

if (endptr != NULL) | |

*endptr = (char *)(any ? s - 1 : nptr); | |

return (acc); | |

} |