Add symlink(2) and symlinkat(2) stub.

libc/Makefile

@@ -481,6 +481,8 @@ unistd/setpgid.o \
 unistd/setuid.o \
 unistd/sfork.o \
 unistd/sleep.o \
+unistd/symlinkat.o \
+unistd/symlink.o \
 unistd/sysconf.o \
 unistd/tcgetpgrp.o \
 unistd/tcsetpgrp.o \

libc/include/unistd.h

@@ -285,8 +285,6 @@ int setregid(gid_t, gid_t);
 int setreuid(uid_t, uid_t);
 pid_t setsid(void);
 void swab(const void* __restrict, void* __restrict, ssize_t);
-int symlink(const char*, const char*);
-int symlinkat(const char*, int, const char*);
 void sync(void);
 int ttyname_r(int, char*, size_t);
 #endif
@@ -349,6 +347,8 @@ int setgid(gid_t);
 int setpgid(pid_t, pid_t);
 int setuid(uid_t);
 unsigned sleep(unsigned);
+int symlink(const char*, const char*);
+int symlinkat(const char*, int, const char*);
 long sysconf(int);
 pid_t tcgetpgrp(int);
 int tcsetpgrp(int, pid_t);

libc/unistd/symlink.cpp

@@ -0,0 +1,31 @@
+/*******************************************************************************
+
+    Copyright(C) Jonas 'Sortie' Termansen 2013.
+
+    This file is part of the Sortix C Library.
+
+    The Sortix C Library is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or (at your
+    option) any later version.
+
+    The Sortix C Library 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 Lesser General Public
+    License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
+
+    unistd/symlink.cpp
+    Create a symbolic link.
+
+*******************************************************************************/
+
+#include <fcntl.h>
+#include <unistd.h>
+
+extern "C" int symlink(const char* oldpath, const char* newpath)
+{
+	return symlinkat(oldpath, AT_FDCWD, newpath);
+}

libc/unistd/symlinkat.cpp

@@ -0,0 +1,35 @@
+/*******************************************************************************
+
+    Copyright(C) Jonas 'Sortie' Termansen 2013.
+
+    This file is part of the Sortix C Library.
+
+    The Sortix C Library is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or (at your
+    option) any later version.
+
+    The Sortix C Library 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 Lesser General Public
+    License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
+
+    unistd/symlinkat.cpp
+    Create a symbolic link.
+
+*******************************************************************************/
+
+#include <sys/syscall.h>
+
+#include <fcntl.h>
+#include <unistd.h>
+
+DEFN_SYSCALL3(int, sys_symlinkat, SYSCALL_LINKAT, const char*, int, const char*);
+
+extern "C" int symlinkat(const char* oldpath, int newdirfd, const char* newpath)
+{
+	return sys_symlinkat(oldpath, newdirfd, newpath);
+}

sortix/include/sortix/syscallnum.h

@@ -144,6 +144,7 @@
 #define SYSCALL_SETPRIORITY 120
 #define SYSCALL_PRLIMIT 121
 #define SYSCALL_DUP3 122
-#define SYSCALL_MAX_NUM 123 /* index of highest constant + 1 */
+#define SYSCALL_SYMLINKAT 123
+#define SYSCALL_MAX_NUM 124 /* index of highest constant + 1 */
 
 #endif

sortix/io.cpp

@@ -595,6 +595,36 @@ static int sys_link(const char* oldpath, const char* newpath)
 	return sys_linkat(AT_FDCWD, oldpath, AT_FDCWD, newpath, 0);
 }
 
+static int sys_symlinkat(const char* oldpath, int newdirfd, const char* newpath)
+{
+	ioctx_t ctx; SetupUserIOCtx(&ctx);
+
+	char* newpathcopy = GetStringFromUser(newpath);
+	if ( !newpathcopy )
+		return -1;
+	const char* newrelpath = newpathcopy;
+	Ref<Descriptor> newfrom(PrepareLookup(&newrelpath, newdirfd));
+	if ( !newfrom ) { delete[] newpathcopy; return -1; }
+
+	char* final_elem;
+	Ref<Descriptor> dir = OpenDirContainingPath(&ctx, newfrom, newpathcopy,
+	                                            &final_elem);
+	delete[] newpathcopy;
+	if ( !dir )
+		return -1;
+
+	char* oldpathcopy = GetStringFromUser(oldpath);
+	if ( !oldpathcopy ) { delete[] final_elem; return -1; }
+
+	int ret = (errno = EPERM, -1);
+
+	delete[] oldpathcopy;
+	delete[] final_elem;
+
+	return ret;
+}
+
+
 static int sys_settermmode(int fd, unsigned mode)
 {
 	Ref<Descriptor> desc = CurrentProcess()->GetDescriptor(fd);
@@ -1019,6 +1049,7 @@ void Init()
 	Syscall::Register(SYSCALL_SEND, (void*) sys_send);
 	Syscall::Register(SYSCALL_SETTERMMODE, (void*) sys_settermmode);
 	Syscall::Register(SYSCALL_STAT, (void*) sys_stat);
+	Syscall::Register(SYSCALL_SYMLINKAT, (void*) sys_symlinkat);
 	Syscall::Register(SYSCALL_TCGETPGRP, (void*) sys_tcgetpgrp);
 	Syscall::Register(SYSCALL_TCGETWINSIZE, (void*) sys_tcgetwinsize);
 	Syscall::Register(SYSCALL_TCSETPGRP, (void*) sys_tcsetpgrp);