Add closefrom(2).

kernel/dtable.cpp

@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2013, 2014.
+    Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2013, 2014, 2015.
 
     This file is part of Sortix.
 
@@ -181,9 +181,8 @@ int DescriptorTable::Copy(int from, int to, int flags)
 	return to;
 }
 
-Ref<Descriptor> DescriptorTable::FreeKeep(int index)
+Ref<Descriptor> DescriptorTable::FreeKeepInternal(int index)
 {
-	ScopedLock lock(&dtablelock);
 	if ( !IsGoodEntry(index) ) { errno = EBADF; return Ref<Descriptor>(NULL); }
 	Ref<Descriptor> ret = entries[index].desc;
 	entries[index].desc.Reset();
@@ -192,6 +191,12 @@ Ref<Descriptor> DescriptorTable::FreeKeep(int index)
 	return ret;
 }
 
+Ref<Descriptor> DescriptorTable::FreeKeep(int index)
+{
+	ScopedLock lock(&dtablelock);
+	return FreeKeepInternal(index);
+}
+
 void DescriptorTable::Free(int index)
 {
 	FreeKeep(index);
@@ -273,4 +278,24 @@ int DescriptorTable::Next(int index)
 	return index;
 }
 
+int DescriptorTable::CloseFrom(int index)
+{
+	if ( index < 0 )
+		return errno = EBADF, -1;
+
+	ScopedLock lock(&dtablelock);
+
+	bool any = false;
+
+	while ( index < numentries )
+	{
+		if ( !IsGoodEntry(index) )
+			continue;
+		FreeKeepInternal(index);
+		any = true;
+	}
+
+	return any ? 0 : (errno = EBADF, -1);
+}
+
 } // namespace Sortix

kernel/include/sortix/kernel/dtable.h

@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2013, 2014.
+    Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2013, 2014, 2015.
 
     This file is part of Sortix.
 
@@ -54,12 +54,14 @@ public:
 	int GetFlags(int index);
 	int Previous(int index);
 	int Next(int index);
+	int CloseFrom(int index);
 
 private:
 	void Reset(); // Hey, reference counted. Don't call this.
 	bool IsGoodEntry(int i);
 	bool Enlargen(int atleast);
 	int AllocateInternal(Ref<Descriptor> desc, int flags, int min_index);
+	Ref<Descriptor> FreeKeepInternal(int index);
 
 private:
 	kthread_mutex_t dtablelock;

kernel/include/sortix/kernel/syscall.h

@@ -60,6 +60,7 @@ int sys_clock_gettimeres(clockid_t, struct timespec*, struct timespec*);
 int sys_clock_nanosleep(clockid_t, int, const struct timespec*, struct timespec*);
 int sys_clock_settimeres(clockid_t, const struct timespec*, const struct timespec*);
 int sys_close(int);
+int sys_closefrom(int);
 int sys_connect(int, const void*, size_t);
 int sys_dispmsg_issue(void*, size_t);
 int sys_dup(int);

kernel/include/sortix/syscall.h

@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2013, 2014.
+    Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2013, 2014, 2015.
 
     This file is part of Sortix.
 
@@ -177,6 +177,7 @@
 #define SYSCALL_SETHOSTNAME 149
 #define SYSCALL_UNMOUNTAT 150
 #define SYSCALL_FSM_MOUNTAT 151
-#define SYSCALL_MAX_NUM 152 /* index of highest constant + 1 */
+#define SYSCALL_CLOSEFROM 152
+#define SYSCALL_MAX_NUM 153 /* index of highest constant + 1 */
 
 #endif

kernel/io.cpp

@@ -126,6 +126,15 @@ int sys_close(int fd)
 	return desc->sync(&ctx);
 }
 
+int sys_closefrom(int fd)
+{
+	ioctx_t ctx; SetupUserIOCtx(&ctx);
+	Ref<DescriptorTable> dtable = CurrentProcess()->GetDTable();
+	int ret = dtable->CloseFrom(fd);
+	dtable.Reset();
+	return ret;
+}
+
 int sys_dup(int fd)
 {
 	Ref<DescriptorTable> dtable = CurrentProcess()->GetDTable();

kernel/syscall.cpp

@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2013, 2014.
+    Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2013, 2014, 2015.
 
     This file is part of Sortix.
 
@@ -187,6 +187,7 @@ void* syscall_list[SYSCALL_MAX_NUM + 1] =
 	[SYSCALL_SETHOSTNAME] = (void*) sys_sethostname,
 	[SYSCALL_UNMOUNTAT] = (void*) sys_unmountat,
 	[SYSCALL_FSM_MOUNTAT] = (void*) sys_fsm_mountat,
+	[SYSCALL_CLOSEFROM] = (void*) sys_closefrom,
 	[SYSCALL_MAX_NUM] = (void*) sys_bad_syscall,
 };
 } // extern "C"

libc/Makefile

@@ -553,6 +553,7 @@ unistd/alarm.o \
 unistd/chdir.o \
 unistd/chown.o \
 unistd/chroot.o \
+unistd/closefrom.o \
 unistd/close.o \
 unistd/confstr.o \
 unistd/dup2.o \

libc/include/unistd.h

@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2013, 2014.
+    Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2013, 2014, 2015.
 
     This file is part of the Sortix C Library.
 
@@ -545,6 +545,7 @@ size_t getpagesize(void);
 /* Functions copied from elsewhere. */
 #if __USE_SORTIX
 int chroot(const char*);
+int closefrom(int);
 int dup3(int, int, int);
 int execvpe(const char*, char* const [], char* const []);
 char* get_current_dir_name(void);

libc/unistd/closefrom.cpp

@@ -0,0 +1,34 @@
+/*******************************************************************************
+
+    Copyright(C) Jonas 'Sortie' Termansen 2015.
+
+    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/closefrom.cpp
+    Closes all file descriptors from a value and upwards.
+
+*******************************************************************************/
+
+#include <sys/syscall.h>
+
+#include <unistd.h>
+
+DEFN_SYSCALL1(int, sys_closefrom, SYSCALL_CLOSEFROM, int);
+
+extern "C" int closefrom(int fd)
+{
+	return sys_closefrom(fd);
+}