1 files changed, 62 insertions, 7 deletions

diff --git a/src/basic/iovec-util.h b/src/basic/iovec-util.h
index 39feabd..8cfa571 100644
--- a/src/basic/iovec-util.h
+++ b/src/basic/iovec-util.h
@@ -8,16 +8,38 @@
 #include "alloc-util.h"
 #include "macro.h"
 
+/* An iovec pointing to a single NUL byte */
+#define IOVEC_NUL_BYTE (const struct iovec) {                   \
+                .iov_base = (void*) (const uint8_t[1]) { 0 },   \
+                .iov_len = 1,                                   \
+        }
+
 size_t iovec_total_size(const struct iovec *iovec, size_t n);
 
 bool iovec_increment(struct iovec *iovec, size_t n, size_t k);
 
-#define IOVEC_MAKE(base, len) (struct iovec) { .iov_base = (base), .iov_len = (len) }
-#define IOVEC_MAKE_STRING(string)                       \
-        ({                                              \
-                const char *_s = (string);              \
-                IOVEC_MAKE((char*) _s, strlen(_s));     \
-        })
+/* This accepts both const and non-const pointers */
+#define IOVEC_MAKE(base, len)                                           \
+        (struct iovec) {                                                \
+                .iov_base = (void*) (base),                             \
+                .iov_len = (len),                                       \
+        }
+
+static inline struct iovec* iovec_make_string(struct iovec *iovec, const char *s) {
+        assert(iovec);
+        /* We don't use strlen_ptr() here, because we don't want to include string-util.h for now */
+        *iovec = IOVEC_MAKE(s, s ? strlen(s) : 0);
+        return iovec;
+}
+
+#define IOVEC_MAKE_STRING(s) \
+        *iovec_make_string(&(struct iovec) {}, s)
+
+#define CONST_IOVEC_MAKE_STRING(s)              \
+        (const struct iovec) {                  \
+                .iov_base = (char*) s,          \
+                .iov_len = STRLEN(s),           \
+        }
 
 static inline void iovec_done(struct iovec *iovec) {
         /* A _cleanup_() helper that frees the iov_base in the iovec */
@@ -35,10 +57,43 @@ static inline void iovec_done_erase(struct iovec *iovec) {
 }
 
 static inline bool iovec_is_set(const struct iovec *iovec) {
+        /* Checks if the iovec points to a non-empty chunk of memory */
         return iovec && iovec->iov_len > 0 && iovec->iov_base;
 }
 
+static inline bool iovec_is_valid(const struct iovec *iovec) {
+        /* Checks if the iovec is either NULL, empty or points to a valid bit of memory */
+        return !iovec || (iovec->iov_base || iovec->iov_len == 0);
+}
+
 char* set_iovec_string_field(struct iovec *iovec, size_t *n_iovec, const char *field, const char *value);
 char* set_iovec_string_field_free(struct iovec *iovec, size_t *n_iovec, const char *field, char *value);
 
-void iovec_array_free(struct iovec *iovec, size_t n);
+void iovec_array_free(struct iovec *iovec, size_t n_iovec);
+
+static inline int iovec_memcmp(const struct iovec *a, const struct iovec *b) {
+
+        if (a == b)
+                return 0;
+
+        return memcmp_nn(a ? a->iov_base : NULL,
+                         a ? a->iov_len : 0,
+                         b ? b->iov_base : NULL,
+                         b ? b->iov_len : 0);
+}
+
+static inline struct iovec *iovec_memdup(const struct iovec *source, struct iovec *ret) {
+        assert(ret);
+
+        if (!iovec_is_set(source))
+                *ret = (struct iovec) {};
+        else {
+                void *p = memdup(source->iov_base, source->iov_len);
+                if (!p)
+                        return NULL;
+
+                *ret = IOVEC_MAKE(p, source->iov_len);
+        }
+
+        return ret;
+}