Permanent storage implementation

1 files changed, 105 insertions, 0 deletions

diff --git a/c_src/erlport.c b/c_src/erlport.c
new file mode 100644
index 0000000..5e5c17c
--- /dev/null
+++ b/c_src/erlport.c
@@ -0,0 +1,105 @@
+/*
+ * Copyright (c) 2014 Kungliga Tekniska Högskolan
+ * (KTH Royal Institute of Technology, Stockholm, Sweden).
+ */
+
+#include <sys/types.h>
+#include <sys/uio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include "net_read_write.h"
+#include "erlport.h"
+
+static ssize_t
+read_length(size_t length_size)
+{
+    unsigned char buf[2];
+
+    if (length_size != 2) {
+        return -1;
+    }
+
+    if (length_size > sizeof(buf)) {
+        return -1;
+    }
+
+    ssize_t ret;
+
+    ret = net_read(0, (char *)buf, length_size);
+
+    if (ret != (ssize_t) length_size) {
+        return -1;
+    }
+
+    return (ssize_t)(((unsigned long)buf[0] << 8) | (unsigned long)buf[1]);
+}
+
+ssize_t
+read_command(char *buf, size_t maxlen)
+{
+    ssize_t len;
+
+    len = read_length(2);
+
+    if (len < 0) {
+        return -1;
+    }
+
+    if (len > (ssize_t) maxlen) {
+        return -1;
+    }
+    return net_read(0, buf, (size_t)len);
+}
+
+static int
+write_length(size_t len, size_t length_size)
+{
+    unsigned char buf[2];
+
+    if (length_size != 2) {
+        return -1;
+    }
+
+    buf[0] = (len >> 8) & 0xff;
+    buf[1] = len & 0xff;
+
+    ssize_t ret;
+
+    ret = net_write(1, (char *)buf, length_size);
+
+    if (ret < 0) {
+        return -1;
+    }
+
+    if (ret != (ssize_t) length_size) {
+        return -1;
+    }
+
+    return 0;
+}
+
+static int
+write_reply(char *msg, size_t len)
+{
+    ssize_t ret;
+
+    ret = write_length(len, 2);
+    if (ret < 0) {
+        return -1;
+    }
+    ret = net_write(1, msg, len);
+    if (ret < 0) {
+        return -1;
+    }
+
+    return 0;
+}
+
+int
+write_status(char *msg)
+{
+    return write_reply(msg, strlen(msg));
+}