1 files changed, 82 insertions, 0 deletions
diff --git a/common/include/utility.h b/common/include/utility.h
new file mode 100644
index 00000000..8619cd21
--- /dev/null
+++ b/common/include/utility.h
@@ -0,0 +1,82 @@
+/* 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 <stdint.h>
+#include <string.h>
+
+/* Outputs an error message and quits. */
+void error(const char *format, ...);
+
+/* Outputs debug/warning messages. */
+void debug(const char *format, ...);
+
+
+#define assert(expr) do { if (!(expr)) { \
+      error("assert fail: %s at %s:%d\n", \
+            #expr, __FILE__, __LINE__); }} while(0)
+
+/* 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;  /* Remaining length of the buffer. */
+  uint8_t overrun;  /* Flag set to 1 when an overrun occurs. */
+} 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, uint64_t 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, uint64_t len);
+
+#endif  /* VBOOT_REFERENCE_UTILITY_H_ */