1 files changed, 73 insertions, 0 deletions
diff --git a/src/stringbuf.c b/src/stringbuf.c
new file mode 100644
index 0000000..bc71dc3
--- /dev/null
+++ b/src/stringbuf.c
@@ -0,0 +1,73 @@
+#include "stringbuf.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+
+int StringBufInit(StringBuf *buf, size_t size)
+{
+    assert(buf != NULL);
+    memset(buf, 0, sizeof(*buf));
+    return StringBufGrow(buf, size);
+}
+
+int StringBufInitFromCString(StringBuf *buf, const char *s, int len)
+{
+    if (len < 0)
+        len = strlen(s);
+    return StringBufInitFromData(buf, s, len);
+}
+
+int StringBufInitFromData(StringBuf *buf, const void *ptr, size_t size)
+{
+    if (StringBufInit(buf, size) != 0)
+        return -1;
+    memcpy(buf->data, ptr, size);
+    buf->len = size;
+    return 0;
+}
+
+void StringBufDeinit(StringBuf *buf)
+{
+    assert(buf != NULL);
+    if (buf->size > 0 && buf->data)
+        free(buf->data);
+    memset(buf, 0, sizeof(*buf));
+}
+
+size_t StringBufAvailable(StringBuf *buf)
+{
+    assert(buf != NULL);
+    assert(buf->data != NULL);
+    assert(buf->len <= buf->size);
+    return buf->size - buf->len;
+}
+
+int StringBufGrow(StringBuf *buf, size_t size)
+{
+    assert(buf != NULL);
+    size_t newSize = buf->size + size;
+    char *ptr = realloc(buf->data, newSize+1);
+    if (!ptr)
+        return -1;
+    buf->data = ptr;
+    buf->size = newSize;
+    buf->data[buf->size] = '\0';
+    return 0;
+}
+
+int StringBufAppendData(StringBuf *buf, const void *ptr, size_t size)
+{
+    assert(buf != NULL);
+    assert(buf->data != NULL);
+    assert(ptr != NULL);
+    assert(size > 0);
+    if (StringBufAvailable(buf) < size)
+    {
+        if (StringBufGrow(buf, size) == -1)
+            return -1;
+    }
+    memcpy(buf->data + buf->len, ptr, size);
+    buf->len += size;
+    return 0;
+}