From ee451671cd0f54ec0d3ed84edcc7186858559924 Mon Sep 17 00:00:00 2001
From: Riyyi <riyyi3@gmail.com>
Date: Sat, 25 Sep 2021 11:29:49 +0200
Subject: [PATCH] Util: Fix reading of file descriptors longer than 4096 bytes

---
 src/util/system.cpp | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/src/util/system.cpp b/src/util/system.cpp
index b8c1246..7d62a9c 100644
--- a/src/util/system.cpp
+++ b/src/util/system.cpp
@@ -1,6 +1,6 @@
 #include <cerrno>     // errno, EAGAIN, EINTR
 #include <cstddef>    // size_t
-#include <cstdio>     // perror
+#include <cstdio>     // perror, ssize_t
 #include <cstdlib>    // exit, WEXITSTATUS
 #include <cstring>    // strcpy, strtok
 #include <functional> // function
@@ -228,13 +228,23 @@ void System::readFromFileDescriptor(int fileDescriptor[2], std::string& output)
 	constexpr int bufferSize = 4096;
 	char buffer[bufferSize];
 
-	do {
+	for (;;) {
 		const ssize_t result = read(fileDescriptor[ReadFileDescriptor], buffer, bufferSize);
-		// FIXME: also handle failure cases
 		if (result > 0) {
 			output.append(buffer, result);
 		}
-	} while (errno == EAGAIN || errno == EINTR);
+		// EOF
+		if (result == 0) {
+			break;
+		}
+		// Error
+		else if (result == -1) {
+			if (errno != EAGAIN && errno != EINTR) {
+				perror("\033[31;1mError:\033[0m read");
+				break;
+			}
+		}
+	}
 
 	close(fileDescriptor[ReadFileDescriptor]);
 }