new classes; yajl library

[chaz/yoink] / yajl / src / yajl_buf.c

diff --git a/yajl/src/yajl_buf.c b/yajl/src/yajl_buf.c
new file mode 100644 (file)
index 0000000..97f1ced
--- /dev/null
+++ b/yajl/src/yajl_buf.c
@@ -0,0 +1,119 @@
+/*
+ * Copyright 2007-2009, Lloyd Hilaiel.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ * 
+ *  1. Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 
+ *  2. Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in
+ *     the documentation and/or other materials provided with the
+ *     distribution.
+ * 
+ *  3. Neither the name of Lloyd Hilaiel nor the names of its
+ *     contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */ 
+
+#include "yajl_buf.h"
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define YAJL_BUF_INIT_SIZE 2048
+
+struct yajl_buf_t {
+    unsigned int len;
+    unsigned int used;
+    unsigned char * data;
+    yajl_alloc_funcs * alloc;
+};
+
+static
+void yajl_buf_ensure_available(yajl_buf buf, unsigned int want)
+{
+    unsigned int need;
+    
+    assert(buf != NULL);
+
+    /* first call */
+    if (buf->data == NULL) {
+        buf->len = YAJL_BUF_INIT_SIZE;
+        buf->data = (unsigned char *) YA_MALLOC(buf->alloc, buf->len);
+        buf->data[0] = 0;
+    }
+
+    need = buf->len;
+
+    while (want >= (need - buf->used)) need <<= 1;
+
+    if (need != buf->len) {
+        buf->data = (unsigned char *) YA_REALLOC(buf->alloc, buf->data, need);
+        buf->len = need;
+    }
+}
+
+yajl_buf yajl_buf_alloc(yajl_alloc_funcs * alloc)
+{
+    yajl_buf b = YA_MALLOC(alloc, sizeof(struct yajl_buf_t));
+    memset((void *) b, 0, sizeof(struct yajl_buf_t));
+    b->alloc = alloc;
+    return b;
+}
+
+void yajl_buf_free(yajl_buf buf)
+{
+    assert(buf != NULL);
+    if (buf->data) YA_FREE(buf->alloc, buf->data);
+    YA_FREE(buf->alloc, buf);
+}
+
+void yajl_buf_append(yajl_buf buf, const void * data, unsigned int len)
+{
+    yajl_buf_ensure_available(buf, len);
+    if (len > 0) {
+        assert(data != NULL);
+        memcpy(buf->data + buf->used, data, len);
+        buf->used += len;
+        buf->data[buf->used] = 0;
+    }
+}
+
+void yajl_buf_clear(yajl_buf buf)
+{
+    buf->used = 0;
+    if (buf->data) buf->data[buf->used] = 0;
+}
+
+const unsigned char * yajl_buf_data(yajl_buf buf)
+{
+    return buf->data;
+}
+
+unsigned int yajl_buf_len(yajl_buf buf)
+{
+    return buf->used;
+}
+
+void
+yajl_buf_truncate(yajl_buf buf, unsigned int len)
+{
+    assert(len <= buf->used);
+    buf->used = len;
+}