utils strbuf: Exponentially increase the buffer size.

That'll make sure that lots of small writes don't result in lots of memory
reallocations.

diff --git a/src/utils/strbuf.c b/src/utils/strbuf.c
index ecc05315ef897f9d84a415ccecb9b6f77e89e9bd..d8a95ac42f60a4003d9cdf21924cbfbf2a5ccee1 100644 (file)
--- a/src/utils/strbuf.c
+++ b/src/utils/strbuf.c
@@ -25,6 +25,7 @@
  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include "sysdb.h"
 #include "utils/strbuf.h"
 
 #include <assert.h>
@@ -65,11 +66,18 @@ struct sdb_strbuf {
 static int
 strbuf_resize(sdb_strbuf_t *buf, size_t new_size)
 {
+       size_t tmp_size;
        char *tmp;
 
        if (new_size <= buf->pos)
                return -1;
 
+       tmp_size = SDB_MAX(buf->size, buf->min_size);
+       if (! tmp_size)
+               tmp_size = 64;
+       while (tmp_size < new_size)
+               tmp_size *= 2;
+
        tmp = realloc(buf->string, new_size);
        if (! tmp)
                return -1;
@@ -231,15 +239,8 @@ sdb_strbuf_memappend(sdb_strbuf_t *buf, const void *data, size_t n)
 
        assert((buf->size == 0) || (buf->string[buf->pos] == '\0'));
 
-       if (buf->pos + n + 1 >= buf->size) {
-               size_t newsize = buf->size * 2;
-
-               if (! newsize)
-                       newsize = 64;
-               while (buf->pos + n + 1 >= newsize)
-                       newsize *= 2;
-
-               if (strbuf_resize(buf, newsize))
+       if (buf->pos + n + 1 > buf->size) {
+               if (strbuf_resize(buf, buf->pos + n + 1))
                        return -1;
        }