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authorMichael Biebl <biebl@debian.org>2019-04-21 21:09:51 +0200
committerMichael Biebl <biebl@debian.org>2019-04-21 21:09:51 +0200
commit85563b7fc7ec2cd21e38debb9b28db342e2e8e7c (patch)
treecce7b0b02d28fae2df9fdf2c1804cacd1500f2d7 /shared/systemd/src/basic/memory-util.h
parent9a6dcbf895f9da01768e64b73cec88c16157d91e (diff)
New upstream version 1.18.0 upstream/1.18.0
Diffstat (limited to 'shared/systemd/src/basic/memory-util.h')
-rw-r--r--shared/systemd/src/basic/memory-util.h84
1 files changed, 84 insertions, 0 deletions
diff --git a/shared/systemd/src/basic/memory-util.h b/shared/systemd/src/basic/memory-util.h
new file mode 100644
index 00000000..915c24a5
--- /dev/null
+++ b/shared/systemd/src/basic/memory-util.h
@@ -0,0 +1,84 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+#pragma once
+
+#include <inttypes.h>
+#include <stdbool.h>
+#include <string.h>
+#include <sys/types.h>
+
+#include "macro.h"
+
+size_t page_size(void) _pure_;
+#define PAGE_ALIGN(l) ALIGN_TO((l), page_size())
+
+/* Normal memcpy requires src to be nonnull. We do nothing if n is 0. */
+static inline void memcpy_safe(void *dst, const void *src, size_t n) {
+        if (n == 0)
+                return;
+        assert(src);
+        memcpy(dst, src, n);
+}
+
+/* Normal memcmp requires s1 and s2 to be nonnull. We do nothing if n is 0. */
+static inline int memcmp_safe(const void *s1, const void *s2, size_t n) {
+        if (n == 0)
+                return 0;
+        assert(s1);
+        assert(s2);
+        return memcmp(s1, s2, n);
+}
+
+/* Compare s1 (length n1) with s2 (length n2) in lexicographic order. */
+static inline int memcmp_nn(const void *s1, size_t n1, const void *s2, size_t n2) {
+        return memcmp_safe(s1, s2, MIN(n1, n2))
+            ?: CMP(n1, n2);
+}
+
+#define memzero(x,l)                                            \
+        ({                                                      \
+                size_t _l_ = (l);                               \
+                void *_x_ = (x);                                \
+                _l_ == 0 ? _x_ : memset(_x_, 0, _l_);           \
+        })
+
+#define zero(x) (memzero(&(x), sizeof(x)))
+
+bool memeqzero(const void *data, size_t length);
+
+#define eqzero(x) memeqzero(x, sizeof(x))
+
+static inline void *mempset(void *s, int c, size_t n) {
+        memset(s, c, n);
+        return (uint8_t*)s + n;
+}
+
+/* Normal memmem() requires haystack to be nonnull, which is annoying for zero-length buffers */
+static inline void *memmem_safe(const void *haystack, size_t haystacklen, const void *needle, size_t needlelen) {
+
+        if (needlelen <= 0)
+                return (void*) haystack;
+
+        if (haystacklen < needlelen)
+                return NULL;
+
+        assert(haystack);
+        assert(needle);
+
+        return memmem(haystack, haystacklen, needle, needlelen);
+}
+
+#if HAVE_EXPLICIT_BZERO
+static inline void* explicit_bzero_safe(void *p, size_t l) {
+        if (l > 0)
+                explicit_bzero(p, l);
+
+        return p;
+}
+#else
+void *explicit_bzero_safe(void *p, size_t l);
+#endif
+
+/* Use with _cleanup_ to erase a single 'char' when leaving scope */
+static inline void erase_char(char *p) {
+        explicit_bzero_safe(p, sizeof(char));
+}