From e105731ee37d7d4d9091c3b7196f6f0c92d95db6 Mon Sep 17 00:00:00 2001
From: Michael Tremer <michael.tremer@ipfire.org>
Date: Fri, 25 Aug 2023 13:10:47 +0000
Subject: [PATCH] arch: Remove using FTS to search interpreter

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---
 src/libpakfire/arch.c | 51 ++++++++++++++++++++++++-------------------
 1 file changed, 29 insertions(+), 22 deletions(-)

diff --git a/src/libpakfire/arch.c b/src/libpakfire/arch.c
index 2dc62585c..b6e963378 100644
--- a/src/libpakfire/arch.c
+++ b/src/libpakfire/arch.c
@@ -19,8 +19,9 @@
 #############################################################################*/
 
 #include <ctype.h>
+#include <dirent.h>
 #include <errno.h>
-#include <fts.h>
+#include <fcntl.h>
 #include <linux/limits.h>
 #include <stddef.h>
 #include <stdio.h>
@@ -208,8 +209,17 @@ int pakfire_arch_supported_by_host(const char* name) {
 	return pakfire_arch_is_compatible(native_arch, name);
 }
 
-static char* find_interpreter(const char* path, const char* magic) {
-	FILE* f = fopen(path, "r");
+static char* find_interpreter(DIR* dir, const char* path, const char* magic) {
+	FILE* f = NULL;
+	int fd = -1;
+
+	// Open the file
+	fd = openat(dirfd(dir), path, O_CLOEXEC);
+	if (fd < 0)
+		return NULL;
+
+	// Re-open the file as file handle
+	f = fdopen(fd, "r");
 	if (!f)
 		return NULL;
 
@@ -259,6 +269,11 @@ static char* find_interpreter(const char* path, const char* magic) {
 }
 
 char* pakfire_arch_find_interpreter(const char* name) {
+	char* interpreter = NULL;
+	DIR* dir = NULL;
+	struct dirent* entry = NULL;
+
+	// Check inputs
 	if (!name) {
 		errno = EINVAL;
 		return NULL;
@@ -267,32 +282,24 @@ char* pakfire_arch_find_interpreter(const char* name) {
 	// If the host supports this architecture natively,
 	// we do not need to search for the interpreter
 	if (pakfire_arch_supported_by_host(name))
-		return NULL;
+		goto ERROR;
 
 	const struct pakfire_arch* arch = pakfire_arch_find(name);
 	if (!arch)
-		return NULL;
-
-	char* interpreter = NULL;
-
-	char* paths[] = {
-		"/proc/sys/fs/binfmt_misc", NULL,
-	};
+		goto ERROR;
 
-	FTS* f = fts_open(paths, FTS_NOCHDIR|FTS_NOSTAT, NULL);
-	if (!f)
+	// Open /proc/sys/fs/binfmt_misc
+	dir = opendir("/proc/sys/fs/binfmt_misc");
+	if (!dir)
 		goto ERROR;
 
 	for (;;) {
-		FTSENT* fent = fts_read(f);
-		if (!fent)
+		entry = readdir(dir);
+		if (!entry)
 			break;
 
-		// Only handle files
-		if (!(fent->fts_info & FTS_F))
-			continue;
-
-		interpreter = find_interpreter(fent->fts_path, arch->magic);
+		// Check if the file matches
+		interpreter = find_interpreter(dir, entry->d_name, arch->magic);
 
 		// End search if we have found a match
 		if (interpreter)
@@ -300,8 +307,8 @@ char* pakfire_arch_find_interpreter(const char* name) {
 	}
 
 ERROR:
-	if (f)
-		fts_close(f);
+	if (dir)
+		closedir(dir);
 
 	return interpreter;
 }
-- 
2.39.5