From fb8031ed6ef076c68d2e336dd156aff52bf622ed Mon Sep 17 00:00:00 2001
From: Marco Bonino <marco.bonino@flow-computing.com>
Date: Tue, 10 Sep 2024 14:56:18 +0300
Subject: [PATCH] Fix dtc_output read when interrupted by EINTR

The read() call may be interrupted by a signal, resulting in an EINTR error.
In this case, read() will return -1 and set errno to EINTR.
This is a common issue when dealing with I/O in a multi-process environment.

Check the error code returned by errno.
If it is EINTR, we can safely retry the read().
---
 riscv/dts.cc | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/riscv/dts.cc b/riscv/dts.cc
index 9751ffeee1..55150f8121 100644
--- a/riscv/dts.cc
+++ b/riscv/dts.cc
@@ -158,9 +158,11 @@ static std::string dtc_compile(const std::string& dtc_input, bool compile)
 
   int got;
   char buf[4096];
-  while ((got = read(dtc_output_pipe[0], buf, sizeof(buf))) > 0) {
-    dtc_output.write(buf, got);
-  }
+  do {
+    while ((got = read(dtc_output_pipe[0], buf, sizeof(buf))) > 0) {
+      dtc_output.write(buf, got);
+    }
+  } while (got == -1 && errno == EINTR); // Retry the read() if it was interrupted by a signal
   if (got == -1) {
     std::cerr << "Failed to read dtc_output: " << strerror(errno) << std::endl;
     exit(1);