base64: fix for unsigned chars (e.g. ARM).

[ccan] / ccan / mem / mem.h

diff --git a/ccan/mem/mem.h b/ccan/mem/mem.h
index dd66cc62cd8cce990aeac17da41962aa2bf74a74..20286dcbefd42f99a7e88932ab1ef4cda115f2e2 100644 (file)
--- a/ccan/mem/mem.h
+++ b/ccan/mem/mem.h
@@ -104,7 +104,7 @@ void *memcchr(void const *data, int c, size_t data_len);
 PURE_FUNCTION
 static inline bool memeq(const void *a, size_t al, const void *b, size_t bl)
 {
-       return al == bl && !memcmp(a, b, bl);
+       return al == bl && (al == 0 || !memcmp(a, b, bl));
 }
 
 /**
@@ -149,6 +149,19 @@ static inline bool memeqstr(const void *data, size_t length, const char *string)
        return memeq(data, length, string, strlen(string));
 }
 
+/**
+ * memeqzero - Is a byte array all zeroes?
+ * @data: byte array
+ * @length: length of @data in bytes
+ *
+ * Example:
+ *     if (memeqzero(somebytes, bytes_len)) {
+ *             printf("somebytes == 0!\n");
+ *     }
+ */
+PURE_FUNCTION
+bool memeqzero(const void *data, size_t length);
+
 /**
  * memstarts_str - Does this byte array start with a string prefix?
  * @a: byte array
@@ -227,4 +240,56 @@ static inline bool memoverlaps(const void *a_, size_t al,
  */
 void memswap(void *a, void *b, size_t n);
 
+#if HAVE_VALGRIND_MEMCHECK_H
+#include <valgrind/memcheck.h>
+static inline void *memcheck_(const void *data, size_t len)
+{
+       VALGRIND_CHECK_MEM_IS_DEFINED(data, len);
+       return (void *)data;
+}
+#else
+static inline void *memcheck_(const void *data, size_t len)
+{
+       (void)len;
+       return (void *)data;
+}
+#endif
+
+#if HAVE_TYPEOF
+/**
+ * memcheck - check that a memory region is initialized
+ * @data: start of region
+ * @len: length in bytes
+ *
+ * When running under valgrind, this causes an error to be printed
+ * if the entire region is not defined.  Otherwise valgrind only
+ * reports an error when an undefined value is used for a branch, or
+ * written out.
+ *
+ * Example:
+ *     // Search for space, but make sure it's all initialized.
+ *     if (memchr(memcheck(somebytes, bytes_len), ' ', bytes_len)) {
+ *             printf("space was found!\n");
+ *     }
+ */
+#define memcheck(data, len) ((__typeof__((data)+0))memcheck_((data), (len)))
+#else
+#define memcheck(data, len) memcheck_((data), (len))
+#endif
+
+/**
+ * memtaint - mark a memory region unused
+ * @data: start of region
+ * @len: length in bytes
+ *
+ * This writes an "0xdeadbeef" eyecatcher repeatedly to the memory.
+ * When running under valgrind, it also tells valgrind that the memory is
+ * uninitialized, triggering valgrind errors if it is used for branches
+ * or written out (or passed to memcheck!) in future.
+ *
+ * Example:
+ *     // We'll reuse this buffer later, but be sure we don't access it.
+ *     memtaint(somebytes, bytes_len);
+ */
+void memtaint(void *data, size_t len);
 #endif /* CCAN_MEM_H */