libposix: add access

qa/lib/c/access.c

@@ -0,0 +1,40 @@
+/*
+ * This file is part of Jehanne.
+ *
+ * Copyright (C) 2017 Giacomo Tesio <giacomo@tesio.it>
+ *
+ * Jehanne is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * Jehanne is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Jehanne.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <u.h>
+#include <lib9.h>
+
+void
+main(void)
+{
+	char *err = nil;
+	if(access("/tmp", AEXIST) != 0)
+		err = "/tmp does not exists";
+	else if(access("/tmp", AREAD) != 0)
+		err = "/tmp is not readable";
+	else if(access("/tmp", AWRITE) != 0)
+		err = "/tmp is not writeable";
+	else if(access("/tmp", AEXEC) != 0)
+		err = "/tmp is not traversable";
+	if(err == nil){
+		print("PASS\n");
+		exits("PASS");
+	} else {
+		print("FAIL: %s\n", err);
+		exits("FAIL");
+	}
+}

qa/lib/c/build.json

@@ -12,6 +12,7 @@
 			"cp *.rc $JEHANNE/arch/$ARCH/qa/lib/c/"
 		],
 		"SourceFilesCmd": [
+			"access.c",
 			"asmscall.c",
 			"cleanname.c",
 			"conswrite.c",

qa/lib/newlib/103-files.c

@@ -39,6 +39,21 @@ main(int argc, char **argv)
 		printf("FAIL: mkdir(qa-files) in /tmp returns %d\n", ret);
 		exit(5);
 	}
+	ret = access("/tmp/qa-files", F_OK);
+	if(ret != 0){
+		printf("FAIL: access(\"/tmp/qa-files\", F_OK) returned %d; errno %d\n", ret, errno);
+		exit(6);
+	}
+	ret = access("/tmp/qa-files", R_OK);
+	if(ret != 0){
+		printf("FAIL: access(\"/tmp/qa-files\", R_OK) returned %d; errno %d\n", ret, errno);
+		exit(7);
+	}
+	ret = access("/tmp/qa-files", X_OK);
+	if(ret != 0){
+		printf("FAIL: access(\"/tmp/qa-files\", X_OK) returned %d; errno %d\n", ret, errno);
+		exit(8);
+	}
 
 	return 0;
 }

sys/include/posix.h

@@ -86,6 +86,7 @@ typedef unsigned long clock_t;
 #define __POSIX_EXIT_SIGNAL_PREFIX "terminated by posix signal "
 #define __POSIX_SIGNAL_PREFIX "posix: "
 
+extern int POSIX_access(int *errnop, const char *path, int amode);
 extern void POSIX_exit(int code) __attribute__((noreturn));
 extern int POSIX_chmod(int *errnop, const char *path, int mode);
 extern int POSIX_fchmodat(int *errnop, int fd, const char *path, long mode, int flag);
@@ -282,6 +283,8 @@ extern int libposix_translate_open(PosixOpenTranslator translation);
 
 extern int libposix_translate_seek_whence(int seek_set, int seek_cur, int seek_end);
 
+extern int libposix_translate_access_mode(int f_ok, int r_ok, int w_ok, int x_ok);
+
 /* Map the main exit status received by POSIX_exit to the exit status
  * string for Jehanne.
  *

sys/src/lib/c/9sys/access.c

@@ -1,7 +1,7 @@
 /*
  * This file is part of Jehanne.
  *
- * Copyright (C) 2016 Giacomo Tesio <giacomo@tesio.it>
+ * Copyright (C) 2016-2017 Giacomo Tesio <giacomo@tesio.it>
  *
  * Jehanne is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -23,6 +23,7 @@ int
 jehanne_access(const char *name, int mode)
 {
 	int fd;
+	Dir *db;
 
 	static char omode[] = {
 		OSTAT,
@@ -40,5 +41,12 @@ jehanne_access(const char *name, int mode)
 		close(fd);
 		return 0;
 	}
+	db = jehanne_dirstat(name);
+	if(db != nil){
+		fd = db->mode & omode[mode&AMASK];
+		jehanne_free(db);
+		if(fd)
+			return 0;
+	}
 	return -1;
 }

sys/src/lib/posix/files.c

@@ -24,6 +24,10 @@
 static PosixStatReader __libposix_stat_reader;
 static PosixOpenTranslator __libposix_open_translation;
 static int __libposix_AT_FDCWD;
+static int __libposix_F_OK;
+static int __libposix_R_OK;
+static int __libposix_W_OK;
+static int __libposix_X_OK;
 
 typedef enum SeekTypes
 {
@@ -87,6 +91,19 @@ libposix_translate_seek_whence(int seek_set, int seek_cur, int seek_end)
 	return 1;
 }
 
+int
+libposix_translate_access_mode(int f_ok, int r_ok, int w_ok, int x_ok)
+{
+	if(__libposix_initialized())
+		return 0;
+
+	__libposix_F_OK = f_ok;
+	__libposix_R_OK = r_ok;
+	__libposix_W_OK = w_ok;
+	__libposix_X_OK = x_ok;
+	return 1;
+}
+
 static SeekTypes
 find_seek_type(int whence)
 {
@@ -99,6 +116,32 @@ find_seek_type(int whence)
 	return -1;
 }
 
+int
+POSIX_access(int *errnop, const char *path, int amode)
+{
+	PosixError e = 0;
+	
+	if(path == nil || path[0] == '\0'){
+		e = PosixENOENT;
+ 	} else if(amode == __libposix_F_OK){
+		if(access(path, AEXIST) == 0)
+			return 0;
+		e = PosixENOENT;
+	} else if(amode & ~(__libposix_R_OK|__libposix_W_OK|__libposix_X_OK))
+		e = PosixEINVAL;
+	else if((amode & __libposix_R_OK) && access(path, AREAD) != 0)
+		e = PosixEACCES;
+	else if((amode & __libposix_W_OK) && access(path, AWRITE) != 0)
+		e = PosixEACCES;
+	else if((amode & __libposix_X_OK) && access(path, AEXEC) != 0)
+		e = PosixEACCES;
+	else
+		return 0;
+
+	*errnop = __libposix_get_errno(e);
+	return -1;
+}
+
 int
 POSIX_pipe(int *errnop, int fildes[2])
 {