X-Git-Url: https://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Fmem%2Fmem.c;h=13027a2a7b0fec1b18ae386f9704d84aed41c5f1;hp=853f975db15c1e0c096387c53973a7bdf3b14095;hb=1d415706a6e948fe6dcc3b5dab45812b297f77a1;hpb=40b45c4cfbf110a8e790366302ff43fa94dc8daa

diff --git a/ccan/mem/mem.c b/ccan/mem/mem.c
index 853f975d..13027a2a 100644
--- a/ccan/mem/mem.c
+++ b/ccan/mem/mem.c
@@ -2,6 +2,7 @@
 
 #include "config.h"
 
+#include <assert.h>
 #include <string.h>
 #include <ccan/mem/mem.h>
 
@@ -40,3 +41,88 @@ void *memrchr(const void *s, int c, size_t n)
 	return NULL;
 }
 #endif
+
+void *mempbrkm(const void *data_, size_t len, const void *accept_, size_t accept_len)
+{
+	const char *data = data_, *accept = accept_;
+	size_t i, j;
+
+	for (i = 0; i < len; i++)
+		for (j = 0; j < accept_len; j++)
+			if (accept[j] == data[i])
+				return (void *)&data[i];
+	return NULL;
+}
+
+void *memcchr(void const *data, int c, size_t data_len)
+{
+	char const *p = data;
+	size_t i;
+
+	for (i = 0; i < data_len; i++)
+		if (p[i] != c)
+			return (void *)&p[i];
+
+	return NULL;
+}
+
+#define MEMSWAP_TMP_SIZE	256
+
+void memswap(void *a, void *b, size_t n)
+{
+	char *ap = a;
+	char *bp = b;
+	char tmp[MEMSWAP_TMP_SIZE];
+
+	assert(!memoverlaps(a, n, b, n));
+
+	while (n) {
+		size_t m = n > MEMSWAP_TMP_SIZE ? MEMSWAP_TMP_SIZE : n;
+
+		memcpy(tmp, bp, m);
+		memcpy(bp, ap, m);
+		memcpy(ap, tmp, m);
+
+		ap += m;
+		bp += m;
+		n -= m;
+	}
+}
+
+bool memeqzero(const void *data, size_t length)
+{
+	const unsigned char *p = data;
+	size_t len;
+
+	/* Check first 16 bytes manually */
+	for (len = 0; len < 16; len++) {
+		if (!length)
+			return true;
+		if (*p)
+			return false;
+		p++;
+		length--;
+	}
+
+	/* Now we know that's zero, memcmp with self. */
+	return memcmp(data, p, length) == 0;
+}
+
+void memtaint(void *data, size_t len)
+{
+	/* Using 16 bytes is a bit quicker than 4 */
+	const unsigned tainter[]
+		= { 0xdeadbeef, 0xdeadbeef, 0xdeadbeef, 0xdeadbeef };
+	char *p = data;
+
+	while (len >= sizeof(tainter)) {
+		memcpy(p, tainter, sizeof(tainter));
+		p += sizeof(tainter);
+		len -= sizeof(tainter);
+	}
+	memcpy(p, tainter, len);
+
+#if HAVE_VALGRIND_MEMCHECK_H
+	VALGRIND_MAKE_MEM_UNDEFINED(data, len);
+#endif
+}