basic: getauxval(AT_RANDOM) is apparently not necessarily aligned

[elogind.git] / src / basic / io-util.h

diff --git a/src/basic/io-util.h b/src/basic/io-util.h
index cd2aa75ad2c6859cde3a9b8f2a58fca1acb4cb6e..7d0d2bd810e7b37e13a7bf28375d9f3919c50e42 100644 (file)
--- a/src/basic/io-util.h
+++ b/src/basic/io-util.h
@@ -22,9 +22,12 @@
 ***/
 
 #include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
 #include <sys/types.h>
 #include <sys/uio.h>
 
+#include "macro.h"
 #include "time-util.h"
 
 int flush_fd(int fd);
@@ -74,3 +77,21 @@ static inline size_t IOVEC_INCREMENT(struct iovec *i, unsigned n, size_t k) {
 
         return k;
 }
+
+static inline bool FILE_SIZE_VALID(uint64_t l) {
+        /* ftruncate() and friends take an unsigned file size, but actually cannot deal with file sizes larger than
+         * 2^63 since the kernel internally handles it as signed value. This call allows checking for this early. */
+
+        return (l >> 63) == 0;
+}
+
+static inline bool FILE_SIZE_VALID_OR_INFINITY(uint64_t l) {
+
+        /* Same as above, but allows one extra value: -1 as indication for infinity. */
+
+        if (l == (uint64_t) -1)
+                return true;
+
+        return FILE_SIZE_VALID(l);
+
+}