sf_iov.[hc] add function sf_iova_memcpy_ex

src/sf_iov.c

@@ -55,6 +55,7 @@ int sf_iova_consume(SFDynamicIOVArray *iova, const int consume_len)
     if (iova->cnt == 0) {
         struct iovec *last;
 
+        /* update the last iov for next slice */
         last = iob - 1;
         last->iov_base = (char *)last->iov_base + last->iov_len;
         last->iov_len = 0;

src/sf_iov.h

@@ -82,6 +82,33 @@ int sf_iova_memset_ex(const struct iovec *iov, const int iovcnt,
 #define sf_iova_memset(iova, c, offset, length) \
     sf_iova_memset_ex((iova).iov, (iova).cnt, c, offset, length)
 
+static inline void sf_iova_memcpy_ex(const struct iovec *iov,
+        const int iovcnt, const char *buff, const int length)
+{
+    const struct iovec *iob;
+    const struct iovec *end;
+    const char *current;
+    int remain;
+    int bytes;
+
+    current = buff;
+    remain = length;
+    end = iov + iovcnt;
+    for (iob=iov; iob<end; iob++) {
+        bytes = FC_MIN(remain, iob->iov_len);
+        memcpy(iob->iov_base, current, bytes);
+
+        remain -= bytes;
+        if (remain == 0) {
+            break;
+        }
+        current += bytes;
+    }
+}
+
+#define sf_iova_memcpy(iova, buff, length) \
+    sf_iova_memcpy_ex((iova).iov, (iova).cnt, buff, length)
+
 #ifdef __cplusplus
 }
 #endif