+/*
+ * Wraps read() function to handle EINTR and partial reads.
+ * On success, it returns `count` received as parameter. On error, it returns a
+ * value smaller than the requested `count`.
+ */
+static inline
+ssize_t bt_common_read(int fd, void *buf, size_t count)
+{
+ size_t i = 0;
+ ssize_t ret;
+
+ BT_ASSERT(buf);
+
+ /* Never return an overflow value. */
+ BT_ASSERT(count <= SSIZE_MAX);
+
+ do {
+ ret = read(fd, buf + i, count - i);
+ if (ret < 0) {
+ if (errno == EINTR) {
+#ifdef BT_LOGD_STR
+ BT_LOGD_STR("read() call interrupted. Retrying...");
+#endif
+ /* retry operation */
+ continue;
+ } else {
+#ifdef BT_LOGE_ERRNO
+ BT_LOGE_ERRNO("Error while reading", ": fd=%d",
+ fd);
+#endif
+ goto end;
+ }
+ }
+ i += ret;
+ BT_ASSERT(i <= count);
+ } while (count - i > 0 && ret > 0);
+
+end:
+ if (ret >= 0) {
+ if (i == 0) {
+ ret = -1;
+ } else {
+ ret = i;
+ }
+ }
+
+ return ret;
+}
+