add serialization to file code

1 files changed, 58 insertions, 1 deletions

diff --git a/common.c b/common.c
index b177987..d72ead3 100644
--- a/common.c
+++ b/common.c
@@ -1,9 +1,12 @@
+#include "common.h"
 #include "config.h"
+
 #include <stdarg.h>
+#include <stdint.h>
+#include <stdio.h>
 #include <strings.h>
 #include <unistd.h>
 
-// wrapper for write
 void writef(char *format, ...)
 {
     va_list args;
@@ -18,3 +21,57 @@ void writef(char *format, ...)
         n++;
     write(0, buf, n);
 }
+
+u16 str_len(char *str)
+{
+    u16 i = 0;
+    while (str[i])
+        i++;
+    return i;
+}
+
+void str_cpy(char *to, char *from)
+{
+    while ((*to++ = *from++))
+        ;
+}
+
+u8 save_message(struct message *msg, FILE *f)
+{
+    u8 err = 0;
+    u16 len;
+    if (msg->text == NULL) {
+        len       = 0;
+        msg->text = ""; // TODO: Error empty message should not be allowed.
+    } else {
+        len = str_len(msg->text);
+    }
+
+    if (len == 0)
+        err = 1;
+
+    fwrite(&msg->timestamp, sizeof(*msg->timestamp) * MSG_TIMESTAMP_LEN, 1, f);
+    fwrite(&msg->author, sizeof(*msg->author) * MSG_AUTHOR_LEN, 1, f);
+    fwrite(&len, sizeof(len), 1, f);
+    fputs(msg->text, f);
+
+    return err;
+}
+
+u8 load_message(struct message *msg, FILE *f)
+{
+    fread(msg, sizeof(*msg->timestamp) * MSG_TIMESTAMP_LEN + sizeof(*msg->author) * MSG_AUTHOR_LEN, 1, f);
+    u16 len;
+    fread(&len, sizeof(len), 1, f);
+    if (len == 0) {
+        // TODO: Error: empty message should not be allowed
+        // empty message
+        msg->text = "";
+        return 1;
+    }
+    char txt[len];
+    fgets(txt, len, f);
+    msg->text = txt;
+
+    return 0;
+}