ext/posix: proposing posix_eaccess. unlike access, it is not standard but available in enough platforms ; on linux it's euidaccess in reality eaccess being 'just' an alias. key difference is eaccess checks the effective user id instead.

Close GH-10917

Author: devnexen

NEWS

@@ -112,6 +112,7 @@ PHP                                                                        NEWS
   . Added posix_pathconf. (David Carlier)
   . Added posix_fpathconf. (David Carlier)
   . Fixed zend_parse_arg_long's bool pointer argument assignment. (Cristian Rodriguez)
+  . Added posix_eaccess. (David Carlier)
 
 - Random:
   . Added Randomizer::getBytesFromString(). (Joshua Rüsweg)

ext/posix/config.m4

@@ -10,7 +10,7 @@ if test "$PHP_POSIX" = "yes"; then
 
   AC_CHECK_HEADERS([sys/mkdev.h sys/sysmacros.h])
 
-  AC_CHECK_FUNCS(seteuid setegid setsid getsid getpgid ctermid mkfifo mknod setrlimit getrlimit getgroups makedev initgroups getgrgid_r posix_pathconf)
+  AC_CHECK_FUNCS(seteuid setegid setsid getsid getpgid ctermid mkfifo mknod setrlimit getrlimit getgroups makedev initgroups getgrgid_r posix_pathconf eaccess)
 
   AC_MSG_CHECKING([for working ttyname_r() implementation])
   AC_RUN_IFELSE([AC_LANG_SOURCE([[

ext/posix/posix.c

@@ -713,6 +713,44 @@ PHP_FUNCTION(posix_access)
 
 	RETURN_TRUE;
 }
+
+#ifdef HAVE_EACCESS
+PHP_FUNCTION(posix_eaccess)
+{
+	zend_long mode = 0;
+	size_t filename_len, ret;
+	char *filename, *path;
+
+	ZEND_PARSE_PARAMETERS_START(1, 2)
+		Z_PARAM_PATH(filename, filename_len)
+		Z_PARAM_OPTIONAL
+		Z_PARAM_LONG(mode)
+	ZEND_PARSE_PARAMETERS_END();
+
+	path = expand_filepath(filename, NULL);
+	if (!path) {
+		zend_argument_value_error(1, "must not be empty");
+		RETURN_THROWS();
+	}
+
+	if (php_check_open_basedir_ex(path, 0)) {
+		efree(path);
+		POSIX_G(last_error) = EPERM;
+		RETURN_FALSE;
+	}
+
+	ret = eaccess(path, mode);
+	efree(path);
+
+	if (ret) {
+		POSIX_G(last_error) = errno;
+		RETURN_FALSE;
+	}
+
+	RETURN_TRUE;
+}
+#endif
+
 /* }}} */
 
 /*

ext/posix/posix.stub.php

@@ -379,6 +379,10 @@ function posix_mknod(string $filename, int $flags, int $major = 0, int $minor =
 
 function posix_access(string $filename, int $flags = 0): bool {}
 
+#ifdef HAVE_EACCESS
+function posix_eaccess(string $filename, int $flags = 0): bool {}
+#endif
+
 /**
  * @return array<string, int|string|array|null>|false
  * @refcount 1

ext/posix/posix_arginfo.h

@@ -0,0 +1,20 @@
+--TEST--
+posix_eaccess() with bogus paths
+--EXTENSIONS--
+posix
+--SKIPIF--
+<?php
+if (!function_exists("posix_eaccess")) die("skip only platforms with posix_eaccess");
+?>
+--FILE--
+<?php
+
+try {
+    posix_eaccess(str_repeat('bogus path', 1042));
+} catch (ValueError $e) {
+    echo $e->getMessage() . PHP_EOL;
+}
+
+?>
+--EXPECT--
+posix_eaccess(): Argument #1 ($filename) must not be empty