From 20d38ed28c85c6963f00bb74266e890f72e5f29c Mon Sep 17 00:00:00 2001
From: Bananymous <oskari.alaranta@bananymous.com>
Date: Wed, 31 Jul 2024 23:53:55 +0300
Subject: [PATCH] LibC/Shell: Implement gethostname() and shell uses it for
 hostname

---
 userspace/libraries/LibC/unistd.cpp | 13 +++++++++++++
 userspace/programs/Shell/main.cpp   | 18 +++---------------
 2 files changed, 16 insertions(+), 15 deletions(-)

diff --git a/userspace/libraries/LibC/unistd.cpp b/userspace/libraries/LibC/unistd.cpp
index 3a68e5ed44..8a85ebab32 100644
--- a/userspace/libraries/LibC/unistd.cpp
+++ b/userspace/libraries/LibC/unistd.cpp
@@ -119,6 +119,19 @@ int isatty(int fildes)
 	return syscall(SYS_ISATTY, fildes) >= 0;
 }
 
+int gethostname(char* name, size_t namelen)
+{
+	FILE* fp = fopen("/etc/hostname", "r");
+	if (fp == NULL)
+		return -1;
+	size_t nread = fread(name, namelen - 1, 1, fp);
+	while (nread > 0 && name[nread - 1] == '\n')
+		nread--;
+	name[nread] = '\0';
+	fclose(fp);
+	return 0;
+}
+
 int execl(const char* pathname, const char* arg0, ...)
 {
 	if (arg0 == nullptr)
diff --git a/userspace/programs/Shell/main.cpp b/userspace/programs/Shell/main.cpp
index 0668d7ec51..1067242d91 100644
--- a/userspace/programs/Shell/main.cpp
+++ b/userspace/programs/Shell/main.cpp
@@ -915,21 +915,9 @@ int main(int argc, char** argv)
 
 	tcgetattr(0, &old_termios);
 
-	{
-		FILE* fp = fopen("/etc/hostname", "r");
-		if (fp != NULL)
-		{
-			char buffer[512];
-			while (size_t nbyte = fread(buffer, 1, sizeof(buffer), fp))
-			{
-				if (nbyte == 0)
-					break;
-				MUST(hostname.append(BAN::StringView(buffer, nbyte)));
-			}
-			fclose(fp);
-		}
-		if (!hostname.empty() && hostname.back() == '\n')
-			hostname.pop_back();
+	char hostname_buffer[HOST_NAME_MAX];
+	if (gethostname(hostname_buffer, sizeof(hostname_buffer)) == 0) {
+		MUST(hostname.append(hostname_buffer));
 	}
 
 	if (argc >= 2)