Corrected an implementation error and added more comments

Author: fangfufu

src/link.c

@@ -722,17 +722,15 @@ LinkTable *LinkTable_disk_open(const char *dirn)
     FREE(metadirn);
 
     if (!fp) {
+        lprintf(debug, "Linktable at %s does not exist.", path);
         FREE(path);
         return NULL;
     }
 
     LinkTable *linktbl = CALLOC(1, sizeof(LinkTable));
 
-    if (sizeof(int) != fread(&linktbl->num, sizeof(int), 1, fp)) {
-        /*
-         * reached EOF
-         */
-        lprintf(error, "reached EOF!\n");
+    if (fread(&linktbl->num, sizeof(int), 1, fp) != 1) {
+        lprintf(error, "Failed to read the first int of %s!\n", path);
         LinkTable_free(linktbl);
         LinkTable_disk_delete(dirn);
         return NULL;

src/link.h

@@ -43,6 +43,7 @@ struct LinkTable {
 struct Link {
     /** \brief The link name in the last level of the URL */
     char linkname[MAX_FILENAME_LEN + 1];
+    /** \brief This is for storing the unescaped path */
     char linkpath[MAX_FILENAME_LEN + 1];
     /** \brief The full URL of the file */
     char f_url[MAX_PATH_LEN + 1];
@@ -116,6 +117,7 @@ int LinkTable_disk_save(LinkTable *linktbl, const char *dirn);
 
 /**
  * \brief load a link table from the disk.
+ * \param[in] dirn We expected the unescaped_path here!
  */
 LinkTable *LinkTable_disk_open(const char *dirn);