From 8a3e760e1b1555f38d0682cc50441f6158a69706 Mon Sep 17 00:00:00 2001
From: Adipks <adipks11@gmail.com>
Date: Sat, 9 Nov 2024 17:17:04 +0530
Subject: [PATCH 1/3] Socket Test

---
 xv6-riscv/.gitignore        |  17 +++++
 xv6-riscv/Makefile          |   2 +
 xv6-riscv/kernel/defs.h     |  11 +++
 xv6-riscv/kernel/file.h     |  12 ++--
 xv6-riscv/kernel/socket.c   | 129 ++++++++++++++++++++++++++++++++++++
 xv6-riscv/kernel/socket.h   |   8 +++
 xv6-riscv/kernel/syscall.c  |   9 +++
 xv6-riscv/kernel/syscall.h  |   1 +
 xv6-riscv/kernel/sysfile.c  |  20 ++++++
 xv6-riscv/user/sockettest.c |  19 ++++++
 xv6-riscv/user/user.h       |  11 +--
 xv6-riscv/user/usys.pl      |   1 +
 12 files changed, 231 insertions(+), 9 deletions(-)
 create mode 100644 xv6-riscv/.gitignore
 create mode 100644 xv6-riscv/kernel/socket.c
 create mode 100644 xv6-riscv/kernel/socket.h
 create mode 100644 xv6-riscv/user/sockettest.c

diff --git a/xv6-riscv/.gitignore b/xv6-riscv/.gitignore
new file mode 100644
index 0000000..07216f3
--- /dev/null
+++ b/xv6-riscv/.gitignore
@@ -0,0 +1,17 @@
+*~
+_*
+*.o
+*.d
+*.asm
+*.sym
+*.img
+vectors.S
+bootblock
+entryother
+initcode
+initcode.out
+kernelmemfs
+mkfs
+kernel/kernel
+user/usys.S
+.gdbinit
diff --git a/xv6-riscv/Makefile b/xv6-riscv/Makefile
index f8c820e..1528618 100644
--- a/xv6-riscv/Makefile
+++ b/xv6-riscv/Makefile
@@ -26,6 +26,7 @@ OBJS = \
   $K/pipe.o \
   $K/exec.o \
   $K/sysfile.o \
+  $K/socket.o \
   $K/kernelvec.o \
   $K/plic.o \
   $K/virtio_disk.o
@@ -139,6 +140,7 @@ UPROGS=\
 	$U/_grind\
 	$U/_wc\
 	$U/_zombie\
+	$U/_sockettest\
 
 fs.img: mkfs/mkfs README $(UPROGS)
 	mkfs/mkfs fs.img README $(UPROGS)
diff --git a/xv6-riscv/kernel/defs.h b/xv6-riscv/kernel/defs.h
index d1b6bb9..7317350 100644
--- a/xv6-riscv/kernel/defs.h
+++ b/xv6-riscv/kernel/defs.h
@@ -185,5 +185,16 @@ void            virtio_disk_init(void);
 void            virtio_disk_rw(struct buf *, int);
 void            virtio_disk_intr(void);
 
+
+//socket
+
+struct         file;
+struct         socket;
+struct         file* socketalloc(void);
+int            socketread(struct file*, uint64, int);
+int            socketwrite(struct file*, uint64, int);
+void           socketclose(struct file*);
+
+
 // number of elements in fixed-size array
 #define NELEM(x) (sizeof(x)/sizeof((x)[0]))
diff --git a/xv6-riscv/kernel/file.h b/xv6-riscv/kernel/file.h
index b076d1d..863de0e 100644
--- a/xv6-riscv/kernel/file.h
+++ b/xv6-riscv/kernel/file.h
@@ -1,12 +1,13 @@
 struct file {
-  enum { FD_NONE, FD_PIPE, FD_INODE, FD_DEVICE } type;
-  int ref; // reference count
+  enum { FD_NONE, FD_PIPE, FD_INODE, FD_DEVICE, FD_SOCKET } type;
+  int ref;
   char readable;
   char writable;
   struct pipe *pipe; // FD_PIPE
   struct inode *ip;  // FD_INODE and FD_DEVICE
-  uint off;          // FD_INODE
-  short major;       // FD_DEVICE
+  uint off;         // FD_INODE
+  short major;      // FD_DEVICE
+  struct socket *sock; // FD_SOCKET
 };
 
 #define major(dev)  ((dev) >> 16 & 0xFFFF)
@@ -38,3 +39,6 @@ struct devsw {
 extern struct devsw devsw[];
 
 #define CONSOLE 1
+
+// Add a new file type for sockets
+#define T_SOCKET 4
diff --git a/xv6-riscv/kernel/socket.c b/xv6-riscv/kernel/socket.c
new file mode 100644
index 0000000..7f6f69b
--- /dev/null
+++ b/xv6-riscv/kernel/socket.c
@@ -0,0 +1,129 @@
+#include "types.h"
+#include "riscv.h"
+#include "defs.h"
+#include "param.h"
+#include "spinlock.h"
+#include "proc.h"
+#include "fs.h"
+#include "sleeplock.h"
+#include "file.h"
+#include "socket.h"
+
+struct file*
+socketalloc(void)
+{
+  struct file *f;
+  struct socket *s;
+
+  f = filealloc();
+  if(f == 0)
+    return 0;
+
+  s = kalloc();
+  if(s == 0){
+    fileclose(f);
+    return 0;
+  }
+
+  initlock(&s->lock, "socket");
+  s->refs = 1;
+  s->read_ptr = 0;
+  s->write_ptr = 0;
+  s->connected = 0;
+
+  f->type = FD_SOCKET;
+  f->readable = 1;
+  f->writable = 1;
+  f->sock = s;
+  f->ref = 1;
+
+  return f;
+}
+
+int
+socketread(struct file *f, uint64 addr, int n)
+{
+  struct socket *s = f->sock;
+  int r;
+
+  if(n < 0)
+    return -1;
+
+  acquire(&s->lock);
+  
+  while(s->read_ptr == s->write_ptr && s->connected){
+    if(myproc()->killed){
+      release(&s->lock);
+      return -1;
+    }
+    sleep(&s->read_ptr, &s->lock);
+  }
+
+  r = 0;
+  while(r < n && s->read_ptr != s->write_ptr){
+    if(copyout(myproc()->pagetable, addr + r, &s->data[s->read_ptr], 1) == -1)
+      break;
+    s->read_ptr = (s->read_ptr + 1) % sizeof(s->data);
+    r++;
+  }
+
+  if(r > 0)
+    wakeup(&s->write_ptr);
+    
+  release(&s->lock);
+  return r;
+}
+
+int
+socketwrite(struct file *f, uint64 addr, int n)
+{
+  struct socket *s = f->sock;
+  int w;
+
+  if(n < 0)
+    return -1;
+
+  acquire(&s->lock);
+
+  w = 0;
+  while(w < n){
+    while(((s->write_ptr + 1) % sizeof(s->data)) == s->read_ptr){
+      if(myproc()->killed){
+        release(&s->lock);
+        return -1;
+      }
+      wakeup(&s->read_ptr);
+      sleep(&s->write_ptr, &s->lock);
+    }
+
+    if(copyin(myproc()->pagetable, &s->data[s->write_ptr], addr + w, 1) == -1)
+      break;
+    
+    s->write_ptr = (s->write_ptr + 1) % sizeof(s->data);
+    w++;
+  }
+
+  if(w > 0)
+    wakeup(&s->read_ptr);
+    
+  release(&s->lock);
+  return w;
+}
+
+void
+socketclose(struct file *f)
+{
+  struct socket *s = f->sock;
+
+  acquire(&s->lock);
+  s->refs--;
+  if(s->refs == 0){
+    s->connected = 0;
+    wakeup(&s->read_ptr);
+    wakeup(&s->write_ptr);
+    release(&s->lock);
+    kfree(s);
+  } else {
+    release(&s->lock);
+  }
+}
\ No newline at end of file
diff --git a/xv6-riscv/kernel/socket.h b/xv6-riscv/kernel/socket.h
new file mode 100644
index 0000000..a37c293
--- /dev/null
+++ b/xv6-riscv/kernel/socket.h
@@ -0,0 +1,8 @@
+struct socket {
+  struct spinlock lock;
+  int refs;           // reference count
+  char data[512];     // socket buffer
+  uint read_ptr;      // read pointer
+  uint write_ptr;     // write pointer
+  int connected;      // connection status
+};
\ No newline at end of file
diff --git a/xv6-riscv/kernel/syscall.c b/xv6-riscv/kernel/syscall.c
index ed65409..4f21a56 100644
--- a/xv6-riscv/kernel/syscall.c
+++ b/xv6-riscv/kernel/syscall.c
@@ -7,6 +7,12 @@
 #include "syscall.h"
 #include "defs.h"
 
+// Add the system call number
+#define SYS_socket 22
+
+
+
+
 // Fetch the uint64 at addr from the current process.
 int
 fetchaddr(uint64 addr, uint64 *ip)
@@ -101,6 +107,7 @@ extern uint64 sys_unlink(void);
 extern uint64 sys_link(void);
 extern uint64 sys_mkdir(void);
 extern uint64 sys_close(void);
+extern uint64 sys_socketalloc(void);
 
 // An array mapping syscall numbers from syscall.h
 // to the function that handles the system call.
@@ -126,6 +133,7 @@ static uint64 (*syscalls[])(void) = {
 [SYS_link]    sys_link,
 [SYS_mkdir]   sys_mkdir,
 [SYS_close]   sys_close,
+[SYS_socketalloc] sys_socketalloc,
 };
 
 void
@@ -145,3 +153,4 @@ syscall(void)
     p->trapframe->a0 = -1;
   }
 }
+
diff --git a/xv6-riscv/kernel/syscall.h b/xv6-riscv/kernel/syscall.h
index bc5f356..699f7a2 100644
--- a/xv6-riscv/kernel/syscall.h
+++ b/xv6-riscv/kernel/syscall.h
@@ -20,3 +20,4 @@
 #define SYS_link   19
 #define SYS_mkdir  20
 #define SYS_close  21
+#define SYS_socketalloc  22
\ No newline at end of file
diff --git a/xv6-riscv/kernel/sysfile.c b/xv6-riscv/kernel/sysfile.c
index 16b668c..d9ba01b 100644
--- a/xv6-riscv/kernel/sysfile.c
+++ b/xv6-riscv/kernel/sysfile.c
@@ -503,3 +503,23 @@ sys_pipe(void)
   }
   return 0;
 }
+
+
+
+uint64
+sys_socketalloc(void)
+{
+  struct file *f;
+  int fd;
+  
+  f = socketalloc();
+  if(f == 0)
+    return -1;
+
+  if((fd = fdalloc(f)) < 0){
+    fileclose(f);
+    return -1;
+  }
+
+  return fd;
+}
diff --git a/xv6-riscv/user/sockettest.c b/xv6-riscv/user/sockettest.c
new file mode 100644
index 0000000..b804072
--- /dev/null
+++ b/xv6-riscv/user/sockettest.c
@@ -0,0 +1,19 @@
+//#include "types.h"
+//#include "stat.h"
+#include "user.h"
+
+int
+main(int argc, char *argv[])
+{
+  int fd;
+
+  fd = socketalloc();
+  if(fd < 0){
+    printf("socketalloc failed\n");
+    exit(1);
+  }
+  
+  printf("socket created: fd=%d\n", fd);
+  close(fd);
+  exit(0);
+}
\ No newline at end of file
diff --git a/xv6-riscv/user/user.h b/xv6-riscv/user/user.h
index f16fe27..086f694 100644
--- a/xv6-riscv/user/user.h
+++ b/xv6-riscv/user/user.h
@@ -22,6 +22,7 @@ int getpid(void);
 char* sbrk(int);
 int sleep(int);
 int uptime(void);
+int socketalloc(void);
 
 // ulib.c
 int stat(const char*, struct stat*);
@@ -32,12 +33,12 @@ int strcmp(const char*, const char*);
 void fprintf(int, const char*, ...) __attribute__ ((format (printf, 2, 3)));
 void printf(const char*, ...) __attribute__ ((format (printf, 1, 2)));
 char* gets(char*, int max);
-uint strlen(const char*);
-void* memset(void*, int, uint);
+unsigned int strlen(const char*);
+void* memset(void*, int, unsigned int);
 int atoi(const char*);
-int memcmp(const void *, const void *, uint);
-void *memcpy(void *, const void *, uint);
+int memcmp(const void *, const void *, unsigned int);
+void *memcpy(void *, const void *, unsigned int);
 
 // umalloc.c
-void* malloc(uint);
+void* malloc(unsigned int);
 void free(void*);
diff --git a/xv6-riscv/user/usys.pl b/xv6-riscv/user/usys.pl
index 01e426e..713acb7 100755
--- a/xv6-riscv/user/usys.pl
+++ b/xv6-riscv/user/usys.pl
@@ -36,3 +36,4 @@ sub entry {
 entry("sbrk");
 entry("sleep");
 entry("uptime");
+entry("socketalloc");
\ No newline at end of file

From 574c03d7b75a6261908ca557e08314f6557c7fc5 Mon Sep 17 00:00:00 2001
From: Adipks <adipks11@gmail.com>
Date: Wed, 13 Nov 2024 23:35:41 +0530
Subject: [PATCH 2/3] Updated socket functions

---
 xv6-riscv/.vscode/settings.json |  5 +++
 xv6-riscv/kernel/syscall.c      |  8 ++++
 xv6-riscv/kernel/syscall.h      |  5 ++-
 xv6-riscv/kernel/sysfile.c      | 44 ++++++++++++++++++++++
 xv6-riscv/user/sockettest.c     | 66 +++++++++++++++++++++++++++++----
 xv6-riscv/user/user.h           |  3 ++
 xv6-riscv/user/usys.pl          |  5 ++-
 7 files changed, 126 insertions(+), 10 deletions(-)
 create mode 100644 xv6-riscv/.vscode/settings.json

diff --git a/xv6-riscv/.vscode/settings.json b/xv6-riscv/.vscode/settings.json
new file mode 100644
index 0000000..64c7ab7
--- /dev/null
+++ b/xv6-riscv/.vscode/settings.json
@@ -0,0 +1,5 @@
+{
+    "files.associations": {
+        "stat.h": "c"
+    }
+}
\ No newline at end of file
diff --git a/xv6-riscv/kernel/syscall.c b/xv6-riscv/kernel/syscall.c
index 4f21a56..a1c0ce8 100644
--- a/xv6-riscv/kernel/syscall.c
+++ b/xv6-riscv/kernel/syscall.c
@@ -108,6 +108,11 @@ extern uint64 sys_link(void);
 extern uint64 sys_mkdir(void);
 extern uint64 sys_close(void);
 extern uint64 sys_socketalloc(void);
+extern uint64 sys_socketread(void);
+extern uint64 sys_socketwrite(void);
+extern uint64 sys_socketclose(void);
+
+
 
 // An array mapping syscall numbers from syscall.h
 // to the function that handles the system call.
@@ -134,6 +139,9 @@ static uint64 (*syscalls[])(void) = {
 [SYS_mkdir]   sys_mkdir,
 [SYS_close]   sys_close,
 [SYS_socketalloc] sys_socketalloc,
+[SYS_socketread]   sys_socketread,
+[SYS_socketwrite]  sys_socketwrite,
+[SYS_socketclose]  sys_socketclose,
 };
 
 void
diff --git a/xv6-riscv/kernel/syscall.h b/xv6-riscv/kernel/syscall.h
index 699f7a2..e2e69a3 100644
--- a/xv6-riscv/kernel/syscall.h
+++ b/xv6-riscv/kernel/syscall.h
@@ -20,4 +20,7 @@
 #define SYS_link   19
 #define SYS_mkdir  20
 #define SYS_close  21
-#define SYS_socketalloc  22
\ No newline at end of file
+#define SYS_socketalloc  22
+#define SYS_socketread   23
+#define SYS_socketwrite   24
+#define SYS_socketclose   25
\ No newline at end of file
diff --git a/xv6-riscv/kernel/sysfile.c b/xv6-riscv/kernel/sysfile.c
index d9ba01b..46877ac 100644
--- a/xv6-riscv/kernel/sysfile.c
+++ b/xv6-riscv/kernel/sysfile.c
@@ -523,3 +523,47 @@ sys_socketalloc(void)
 
   return fd;
 }
+
+uint64 sys_socketread(void) {
+    int fd;
+    struct file* f;
+    uint64 addr;
+    int n;
+
+    if (argfd(0, &fd, &f) < 0) {
+        return -1;
+    }
+
+    argaddr(1, &addr);
+    argint(2, &n);
+
+    return socketread(f, addr, n);
+}
+
+uint64 sys_socketwrite(void) {
+    int fd;
+    struct file* f;
+    uint64 addr;
+    int n;
+
+    if (argfd(0, &fd, &f) < 0) {
+        return -1;
+    }
+
+    argaddr(1, &addr);
+    argint(2, &n);
+
+    return socketwrite(f, addr, n);
+}
+
+uint64 sys_socketclose(void) {
+    int fd;
+    struct file* f;
+
+    if (argfd(0, &fd, &f) < 0) {
+        return -1;
+    }
+
+    socketclose(f);
+    return 0;
+}
\ No newline at end of file
diff --git a/xv6-riscv/user/sockettest.c b/xv6-riscv/user/sockettest.c
index b804072..d1fe8b1 100644
--- a/xv6-riscv/user/sockettest.c
+++ b/xv6-riscv/user/sockettest.c
@@ -1,19 +1,69 @@
-//#include "types.h"
-//#include "stat.h"
+// #include "kernel/types.h"
+// #include "kernel/stat.h"
+// #include "user.h"
+
+// int
+// main(int argc, char *argv[])
+// {
+//   int fd;
+
+//   fd = socketalloc();
+//   if(fd < 0){
+//     printf("socketalloc failed\n");
+//     exit(1);
+//   }
+  
+//   printf("socket created: fd=%d\n", fd);
+//   close(fd);
+//   exit(0);
+// }
+
+#include "kernel/types.h"
+#include "kernel/stat.h"
 #include "user.h"
 
+#define BUFFER_SIZE 64
+
 int
 main(int argc, char *argv[])
 {
-  int fd;
+  int sockfd;
+  char buf[BUFFER_SIZE];
+  int n;
 
-  fd = socketalloc();
-  if(fd < 0){
+  // Create a socket
+  sockfd = socketalloc();
+  if(sockfd < 0){
     printf("socketalloc failed\n");
     exit(1);
   }
-  
-  printf("socket created: fd=%d\n", fd);
-  close(fd);
+  printf("Socket created: fd=%d\n", sockfd);
+
+  // Write some data to the socket
+  const char* msg = "Hello from sockettest!";
+  if(socketwrite(sockfd, msg, strlen(msg)) < 0){
+    printf("socketwrite failed\n");
+    socketclose(sockfd);
+    exit(1);
+  }
+  printf("Wrote data to socket\n");
+
+  // Read data from the socket
+  n = socketread(sockfd, buf, BUFFER_SIZE-1);
+  if(n < 0){
+    printf("socketread failed\n");
+    socketclose(sockfd);
+    exit(1);
+  }
+  buf[n] = '\0';
+  printf("Read from socket: %s\n", buf);
+
+  // Close the socket
+  if(socketclose(sockfd) < 0){
+    printf("socketclose failed\n");
+    exit(1);
+  }
+  printf("Socket closed\n");
+
   exit(0);
 }
\ No newline at end of file
diff --git a/xv6-riscv/user/user.h b/xv6-riscv/user/user.h
index 086f694..f2663d8 100644
--- a/xv6-riscv/user/user.h
+++ b/xv6-riscv/user/user.h
@@ -23,6 +23,9 @@ char* sbrk(int);
 int sleep(int);
 int uptime(void);
 int socketalloc(void);
+int socketread(int, void*, int);
+int socketwrite(int, const void*, int);
+int socketclose(int);
 
 // ulib.c
 int stat(const char*, struct stat*);
diff --git a/xv6-riscv/user/usys.pl b/xv6-riscv/user/usys.pl
index 713acb7..f14d4fa 100755
--- a/xv6-riscv/user/usys.pl
+++ b/xv6-riscv/user/usys.pl
@@ -36,4 +36,7 @@ sub entry {
 entry("sbrk");
 entry("sleep");
 entry("uptime");
-entry("socketalloc");
\ No newline at end of file
+entry("socketalloc");
+entry("socketread");
+entry("socketwrite");
+entry("socketclose");
\ No newline at end of file

From 41d4c23cd4ff54a1f5f117943209f5d8bdeee651 Mon Sep 17 00:00:00 2001
From: Adipks <adipks11@gmail.com>
Date: Wed, 13 Nov 2024 23:43:10 +0530
Subject: [PATCH 3/3] Updated socket functions

---
 xv6-riscv/user/sockettest.c | 20 --------------------
 1 file changed, 20 deletions(-)

diff --git a/xv6-riscv/user/sockettest.c b/xv6-riscv/user/sockettest.c
index d1fe8b1..1e8b162 100644
--- a/xv6-riscv/user/sockettest.c
+++ b/xv6-riscv/user/sockettest.c
@@ -1,23 +1,3 @@
-// #include "kernel/types.h"
-// #include "kernel/stat.h"
-// #include "user.h"
-
-// int
-// main(int argc, char *argv[])
-// {
-//   int fd;
-
-//   fd = socketalloc();
-//   if(fd < 0){
-//     printf("socketalloc failed\n");
-//     exit(1);
-//   }
-  
-//   printf("socket created: fd=%d\n", fd);
-//   close(fd);
-//   exit(0);
-// }
-
 #include "kernel/types.h"
 #include "kernel/stat.h"
 #include "user.h"