| /* |
| * Copyright (C) the libgit2 contributors. All rights reserved. |
| * |
| * This file is part of libgit2, distributed under the GNU GPL v2 with |
| * a Linking Exception. For full terms see the included COPYING file. |
| */ |
| #ifndef INCLUDE_integer_h__ |
| #define INCLUDE_integer_h__ |
| |
| /** @return true if p fits into the range of a size_t */ |
| GIT_INLINE(int) git__is_sizet(git_off_t p) |
| { |
| size_t r = (size_t)p; |
| return p == (git_off_t)r; |
| } |
| |
| /** @return true if p fits into the range of an ssize_t */ |
| GIT_INLINE(int) git__is_ssizet(size_t p) |
| { |
| ssize_t r = (ssize_t)p; |
| return p == (size_t)r; |
| } |
| |
| /** @return true if p fits into the range of a uint32_t */ |
| GIT_INLINE(int) git__is_uint32(size_t p) |
| { |
| uint32_t r = (uint32_t)p; |
| return p == (size_t)r; |
| } |
| |
| /** @return true if p fits into the range of an unsigned long */ |
| GIT_INLINE(int) git__is_ulong(git_off_t p) |
| { |
| unsigned long r = (unsigned long)p; |
| return p == (git_off_t)r; |
| } |
| |
| /** @return true if p fits into the range of an int */ |
| GIT_INLINE(int) git__is_int(long long p) |
| { |
| int r = (int)p; |
| return p == (long long)r; |
| } |
| |
| /** |
| * Sets `one + two` into `out`, unless the arithmetic would overflow. |
| * @return true if the result fits in a `uint64_t`, false on overflow. |
| */ |
| GIT_INLINE(bool) git__add_uint64_overflow(uint64_t *out, uint64_t one, uint64_t two) |
| { |
| if (UINT64_MAX - one < two) |
| return true; |
| *out = one + two; |
| return false; |
| } |
| |
| /* Use clang/gcc compiler intrinsics whenever possible */ |
| #if (SIZE_MAX == UINT_MAX) && __has_builtin(__builtin_uadd_overflow) |
| # define git__add_sizet_overflow(out, one, two) \ |
| __builtin_uadd_overflow(one, two, out) |
| # define git__multiply_sizet_overflow(out, one, two) \ |
| __builtin_umul_overflow(one, two, out) |
| #elif (SIZE_MAX == ULONG_MAX) && __has_builtin(__builtin_uaddl_overflow) |
| # define git__add_sizet_overflow(out, one, two) \ |
| __builtin_uaddl_overflow(one, two, out) |
| # define git__multiply_sizet_overflow(out, one, two) \ |
| __builtin_umull_overflow(one, two, out) |
| #else |
| |
| /** |
| * Sets `one + two` into `out`, unless the arithmetic would overflow. |
| * @return true if the result fits in a `size_t`, false on overflow. |
| */ |
| GIT_INLINE(bool) git__add_sizet_overflow(size_t *out, size_t one, size_t two) |
| { |
| if (SIZE_MAX - one < two) |
| return true; |
| *out = one + two; |
| return false; |
| } |
| |
| /** |
| * Sets `one * two` into `out`, unless the arithmetic would overflow. |
| * @return true if the result fits in a `size_t`, false on overflow. |
| */ |
| GIT_INLINE(bool) git__multiply_sizet_overflow(size_t *out, size_t one, size_t two) |
| { |
| if (one && SIZE_MAX / one < two) |
| return true; |
| *out = one * two; |
| return false; |
| } |
| |
| #endif |
| |
| #endif /* INCLUDE_integer_h__ */ |