From c15827cdc4f888a46f219f31d8d2c77f6ba935b8 Mon Sep 17 00:00:00 2001
From: Alejandro Colomar <alx@kernel.org>
Date: Tue, 25 Feb 2025 00:05:11 +0100
Subject: [PATCH] configure.ac, contrib/, src/: Remove dead code

Both glibc and musl provide getusershell(3).  It's an API from 4.3BSD,
according to the manual page, so let's assume it exists everywhere that
we would care, even if it's not in POSIX.

Reported-by: Chris Hofstaedtler <zeha@debian.org>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
---
 configure.ac      |  2 +-
 contrib/adduser.c |  5 ++---
 src/chsh.c        | 26 +-------------------------
 3 files changed, 4 insertions(+), 29 deletions(-)

diff --git a/configure.ac b/configure.ac
index 46bd58e3b..d7321b3cf 100644
--- a/configure.ac
+++ b/configure.ac
@@ -40,7 +40,7 @@ dnl shadow now uses the libc's shadow implementation
 AC_CHECK_HEADER([shadow.h],,[AC_MSG_ERROR([You need a libc with shadow.h])])
 
 AC_CHECK_FUNCS(arc4random_buf futimes \
-	getentropy getrandom getusershell \
+	getentropy getrandom \
 	lckpwdf lutimes \
 	updwtmpx innetgr \
 	getspnam_r \
diff --git a/contrib/adduser.c b/contrib/adduser.c
index 8061c76a4..5c3fec787 100644
--- a/contrib/adduser.c
+++ b/contrib/adduser.c
@@ -127,7 +127,6 @@
 #define EXPIRE_VALS_SET		/* If defined, 'normal' users can't change 
 				 * password expiry values (if running suid root) */
 
-#define HAVE_GETUSERSHELL	/* FIXME: Isn't this defined in config.h too? */
 #define LOGGING			/* If we want to log various things to syslog */
 #define MAX_USRNAME  8		/* Longer usernames seem to work on my system....
 				 * But they're probably a poor idea */
@@ -314,13 +313,13 @@ main (void)
 	{
 	  char *sh;
 	  int ok = 0;
-#ifdef HAVE_GETUSERSHELL
+
 	  setusershell ();
 	  while ((sh = getusershell ()) != NULL)
 	    if (streq(shell, sh))
 	      ok = 1;
 	  endusershell ();
-#endif
+
 	  if (!ok)
 	    {
 	      if (getuid () == 0)
diff --git a/src/chsh.c b/src/chsh.c
index ecd5749ab..b45dca714 100644
--- a/src/chsh.c
+++ b/src/chsh.c
@@ -196,9 +196,8 @@ static bool shell_is_listed (const char *sh)
 static bool shell_is_listed (const char *sh)
 {
 	bool found = false;
-
-#ifdef HAVE_GETUSERSHELL
 	char *cp;
+
 	setusershell ();
 	while ((cp = getusershell ())) {
 		if (streq(cp, sh)) {
@@ -207,30 +206,7 @@ static bool shell_is_listed (const char *sh)
 		}
 	}
 	endusershell ();
-#else
-	char *buf = NULL;
-	FILE *fp;
-	size_t n = 0;
-
-	fp = fopen (SHELLS_FILE, "r");
-	if (NULL == fp) {
-		return false;
-	}
 
-	while (getline (&buf, &n, fp) != -1) {
-		if (buf[0] != '/') {
-			continue;
-		}
-
-		if (streq(buf, sh)) {
-			found = true;
-			break;
-		}
-	}
-
-	free(buf);
-	fclose (fp);
-#endif
 	return found;
 }
 #endif /* with HAVE_VENDORDIR */