feature: resume read system call upon EINTR during file readall.

Author: thibaultcha

src/lib_io.c

@@ -164,8 +164,14 @@ static void io_file_readall(lua_State *L, FILE *fp)
   MSize m, n;
   for (m = LUAL_BUFFERSIZE, n = 0; ; m += m) {
     char *buf = lj_buf_tmp(L, m);
-    n += (MSize)fread(buf+n, 1, m-n, fp);
-    if (n != m) {
+    for (;;) {
+      n += (MSize)fread(buf+n, 1, m-n, fp);
+      if (n == m) break;
+      else if (ferror(fp) != 0) {
+        if (errno != EINTR) return;
+        clearerr(fp); /* EINTR, retry */
+        continue;
+      }
       setstrV(L, L->top++, lj_str_new(L, buf, (size_t)n));
       lj_gc_check(L);
       return;