[PATCH pseudo v2] ports/linux: wrap faccessat()

[Max Kellermann <max+openembedded@blarg.de>]

From: Max Kellermann <max.kellermann@gmail.com>

Signed-off-by: Max Kellermann <max.kellermann@gmail.com>
---
 ports/linux/guts/faccessat.c | 33 +++++++++++++++++++++++++++++++++
 ports/linux/wrapfuncs.in     |  1 +
 2 files changed, 34 insertions(+)
 create mode 100644 ports/linux/guts/faccessat.c

diff --git a/ports/linux/guts/faccessat.c b/ports/linux/guts/faccessat.c
new file mode 100644
index 0000000..64189fa
--- /dev/null
+++ b/ports/linux/guts/faccessat.c
@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2019 Max Kellermann <max.kellermann@gmail.com>
+ * guts/COPYRIGHT for information.
+ *
+ * SPDX-License-Identifier: LGPL-2.1-only
+ *
+ * static int
+ * wrap_faccessat(int dirfd, const char *path, int mode, int flags) {
+ *	int rc = -1;
+ */
+	struct stat64 buf;
+
+	/* note:  no attempt to handle the case where user isn't
+	 * root.
+	 */
+	rc = real___fxstatat64(_STAT_VER, dirfd, path, &buf, flags);
+	if (rc == -1)
+		return rc;
+
+	if (mode & X_OK) {
+		if (buf.st_mode & 0111) {
+			return 0;
+		} else {
+			errno = EPERM;
+			return -1;
+		}
+	} else {
+		return 0;
+	}
+
+/*	return rc;
+ * }
+ */
diff --git a/ports/linux/wrapfuncs.in b/ports/linux/wrapfuncs.in
index a129eba..2a118fc 100644
--- a/ports/linux/wrapfuncs.in
+++ b/ports/linux/wrapfuncs.in
@@ -56,3 +56,4 @@ int getgrent_r(struct group *gbuf, char *buf, size_t buflen, struct group **gbuf
 int capset(cap_user_header_t hdrp, const cap_user_data_t datap); /* real_func=pseudo_capset */
 long syscall(long nr, ...); /* hand_wrapped=1 */
 int renameat2(int olddirfd, const char *oldpath, int newdirfd, const char *newpath, unsigned int flags); /* flags=AT_SYMLINK_NOFOLLOW */
+int faccessat(int dirfd, const char *path, int mode, int flags);
-- 
2.20.1