0001-adding-a-system-call-to-get-open-fds-by-a-process.patch

From fb4ad94f8e3d932cdbe295c47e31388c05ceffcb Mon Sep 17 00:00:00 2001
From: Pawan <pawanprakash101@gmail.com>
Date: Sun, 31 Aug 2014 00:15:38 +0530
Subject: [PATCH] adding a system call to get open fds by a process

---
 Makefile  |    1 +
 ofile.c   |   19 +++++++++++++++++++
 syscall.c |    2 ++
 syscall.h |    1 +
 sysfile.c |   12 ++++++++++++
 user.h    |    1 +
 usys.S    |    1 +
 7 files changed, 37 insertions(+)
 create mode 100644 ofile.c

diff --git a/Makefile b/Makefile
index 2643bbf..53ee9f2 100644
--- a/Makefile
+++ b/Makefile
@@ -171,6 +171,7 @@ UPROGS=\
 	_wc\
 	_zombie\
 	_ps\
+	_ofile\
 
 fs.img: mkfs README $(UPROGS)
 	./mkfs fs.img README $(UPROGS)
diff --git a/ofile.c b/ofile.c
new file mode 100644
index 0000000..661a4cd
--- /dev/null
+++ b/ofile.c
@@ -0,0 +1,19 @@
+#include "types.h"
+#include "user.h"
+#include "fcntl.h"
+
+int main()
+{
+	int fd = open("a.txt", O_RDONLY);
+	printf(1, "1. fd = %d\n", fd);
+	fd = open("a.txt", O_RDONLY);
+	printf(1, "2. fd = %d\n", fd);
+	ofile();
+	close(0);
+	ofile();
+	close(1);
+	ofile();
+	close(2);
+	ofile();
+	exit();
+}
diff --git a/syscall.c b/syscall.c
index f65fb7e..4ecce93 100644
--- a/syscall.c
+++ b/syscall.c
@@ -99,6 +99,7 @@ extern int sys_wait(void);
 extern int sys_write(void);
 extern int sys_uptime(void);
 extern int sys_ps(void);
+extern int sys_ofile(void);
 
 static int (*syscalls[])(void) = {
 [SYS_fork]    sys_fork,
@@ -123,6 +124,7 @@ static int (*syscalls[])(void) = {
 [SYS_mkdir]   sys_mkdir,
 [SYS_close]   sys_close,
 [SYS_ps]      sys_ps,
+[SYS_ofile]   sys_ofile,
 };
 
 void
diff --git a/syscall.h b/syscall.h
index dfe8c32..de73d67 100644
--- a/syscall.h
+++ b/syscall.h
@@ -21,3 +21,4 @@
 #define SYS_mkdir  20
 #define SYS_close  21
 #define SYS_ps     22
+#define SYS_ofile  23
diff --git a/sysfile.c b/sysfile.c
index efbfc77..a52a961 100644
--- a/sysfile.c
+++ b/sysfile.c
@@ -106,6 +106,18 @@ int sys_ps(void)
   return 0;
 }
 
+int sys_ofile(void)
+{
+  int fd; 
+
+  for(fd = 0; fd < NOFILE; fd++) {
+    if(proc->ofile[fd])
+      cprintf("%d ", fd);
+  }
+  cprintf("\n");
+	return 0;
+}
+
 int
 sys_fstat(void)
 {
diff --git a/user.h b/user.h
index 5a75103..2ecf733 100644
--- a/user.h
+++ b/user.h
@@ -23,6 +23,7 @@ char* sbrk(int);
 int sleep(int);
 int uptime(void);
 int ps(void);
+int ofile(void);
 
 // ulib.c
 int stat(char*, struct stat*);
diff --git a/usys.S b/usys.S
index f60a533..f2008f6 100644
--- a/usys.S
+++ b/usys.S
@@ -30,3 +30,4 @@ SYSCALL(sbrk)
 SYSCALL(sleep)
 SYSCALL(uptime)
 SYSCALL(ps)
+SYSCALL(ofile)
-- 
1.7.9.5