[PATCH] Offset verification header by a user-specified distance

[fio.git] / verify.c

diff --git a/verify.c b/verify.c
index a362933d3115e9f340fe351cd8db2bdffdf8a0a8..8bc34571076d403475e764a4ec41df6554234431 100644 (file)
--- a/verify.c
+++ b/verify.c
@@ -32,6 +32,14 @@ static void fill_random_bytes(struct thread_data *td,
        }
 }
 
+void memswp(void* buf1, void* buf2, unsigned int len)
+{
+       struct verify_header swap;
+       memcpy(&swap, buf1, len);
+       memcpy(buf1, buf2, len);
+       memcpy(buf2, &swap, len);
+}
+
 static void hexdump(void *buffer, int len)
 {
        unsigned char *p = buffer;
@@ -161,6 +169,9 @@ int verify_io_u(struct thread_data *td, struct io_u *io_u)
                hdr_inc = td->o.header_interval;
 
        for (; p < (unsigned char*) io_u->buf + io_u->buflen; p += hdr_inc) {
+               if (td->o.header_offset)
+                       memswp(p, &p[td->o.header_offset], sizeof(*hdr));
+
                hdr = (struct verify_header*) p;
 
                if (hdr->fio_magic != FIO_HDR_MAGIC) {
@@ -229,27 +240,28 @@ static void fill_md5(struct verify_header *hdr, void *p, unsigned int len)
  */
 void populate_verify_io_u(struct thread_data *td, struct io_u *io_u)
 {
-       const unsigned int len = io_u->buflen - sizeof(struct verify_header);
        struct verify_header *hdr;
        unsigned char *p = io_u->buf, *data;
-       unsigned int data_len;
+       unsigned int hdr_inc, data_len;
 
        if (td->o.verify == VERIFY_NULL)
                return;
 
-       fill_random_bytes(td, p, len);
+       fill_random_bytes(td, p, io_u->buflen);
+
+       hdr_inc = io_u->buflen;
+       if (td->o.header_interval)
+               hdr_inc = td->o.header_interval;
+       data_len = hdr_inc - sizeof(*hdr);
 
-       for (;p < (unsigned char*) io_u->buf + io_u->buflen; p += hdr->len) {
+       for (;p < (unsigned char*) io_u->buf + io_u->buflen; p += hdr_inc) {
                hdr = (struct verify_header*) p;
 
                hdr->fio_magic = FIO_HDR_MAGIC;
                hdr->verify_type = td->o.verify;
-               hdr->len = io_u->buflen;
-               if (td->o.header_interval)
-                       hdr->len = td->o.header_interval;
+               hdr->len = hdr_inc;
 
                data = p + sizeof(*hdr);
-               data_len = hdr->len - sizeof(*hdr);
                switch (td->o.verify) {
                case VERIFY_MD5:
                        fill_md5(hdr, data, data_len);
@@ -270,6 +282,8 @@ void populate_verify_io_u(struct thread_data *td, struct io_u *io_u)
                        log_err("fio: bad verify type: %d\n", td->o.verify);
                        assert(0);
                }
+               if (td->o.header_offset)
+                       memswp(p, &p[td->o.header_offset], sizeof(*hdr));
        }
 }