| /* Copyright (c) 2010 The Chromium OS Authors. All rights reserved. |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| /* Helper functions/wrappers for memory allocations, manipulation and |
| * comparison. |
| */ |
| |
| #ifndef VBOOT_REFERENCE_UTILITY_H_ |
| #define VBOOT_REFERENCE_UTILITY_H_ |
| |
| #include <inttypes.h> |
| #include <string.h> |
| |
| /* Combine [msw] and [lsw] uint16s to a uint32_t with its [msw] and |
| * [lsw] forming the most and least signficant 16-bit words. |
| */ |
| #define CombineUint16Pair(msw,lsw) (((msw) << 16) | \ |
| (((lsw)) & 0xFFFF)) |
| /* Return the minimum of (a) or (b). */ |
| #define Min(a, b) (((a) < (b)) ? (a) : (b)) |
| |
| /* Allocate [size] bytes and return a pointer to the allocated memory. Abort |
| * on error. |
| */ |
| void* Malloc(size_t size); |
| |
| /* Free memory pointed by [ptr] previously allocated by Malloc(). */ |
| void Free(void* ptr); |
| |
| /* Copy [n] bytes from [src] to [dest]. */ |
| void* Memcpy(void* dest, const void* src, size_t n); |
| |
| /* Set [n] bytes starting at [s] to [c]. */ |
| void* Memset(void *dest, const uint8_t c, size_t n); |
| |
| /* Compare [n] bytes starting at [s1] with [s2] and return 0 if they match, |
| * 1 if they don't. Time taken to perform the comparison is only dependent on |
| * [n] and not on the relationship of the match between [s1] and [s2]. |
| */ |
| int SafeMemcmp(const void* s1, const void* s2, size_t n); |
| |
| /* Track remaining data to be read in a buffer. */ |
| typedef struct MemcpyState { |
| void* remaining_buf; |
| uint64_t remaining_len; |
| } MemcpyState; |
| |
| /* Copy [len] bytes into [dst] only if there's enough data to read according |
| * to [state]. |
| * On success, return [dst] and update [state]. |
| * On failure, return NULL, set remaining len in state to -1. |
| * |
| * Useful for iterating through a binary blob to populate a struct. After the |
| * first failure (buffer overrun), successive calls will always fail. |
| */ |
| void* StatefulMemcpy(MemcpyState* state, void* dst, int len); |
| |
| /* Like StatefulMemcpy() but copies in the opposite direction, populating |
| * data from [src] into the buffer encapsulated in state [state]. |
| * On success, return [src] and update [state]. |
| * On failure, return NULL, set remaining_len in state to -1. |
| * |
| * Useful for iterating through a structure to populate a binary blob. After the |
| * first failure (buffer overrun), successive calls will always fail. |
| */ |
| const void* StatefulMemcpy_r(MemcpyState* state, const void* src, int len); |
| |
| #endif /* VBOOT_REFERENCE_UTILITY_H_ */ |