preparing switch to ELF userspace

4 files changed, 239 insertions, 0 deletions

diff --git a/userspace/sys/crt0.S b/userspace/sys/crt0.S
new file mode 100644
index 0000000..48eadd9
--- /dev/null
+++ b/userspace/sys/crt0.S
@@ -0,0 +1,23 @@
+.global _start
+
+.extern main
+.extern exit
+
+_start:
+
+push $0
+call sbrk
+
+#push $[_BSS_END_]
+#call sbrk
+
+call main
+
+
+push %eax
+call _exit
+
+# this should never be reached anyway!
+.wait:
+    hlt
+jmp .wait
diff --git a/userspace/sys/oldlinker.ld b/userspace/sys/oldlinker.ld
new file mode 100644
index 0000000..4eee8eb
--- /dev/null
+++ b/userspace/sys/oldlinker.ld
@@ -0,0 +1,25 @@
+OUTPUT_FORMAT(binary)
+
+SECTIONS
+{
+    . = 0x800000;
+
+  .text : ALIGN(0x1000) {
+	_TEXT_START_ = .;
+	*(.text)
+	_TEXT_END_ = .;
+  }
+
+  .data : ALIGN(0x1000) {
+      _DATA_START_ = .;
+      *(.data)
+      _DATA_END_ = .;
+  }
+
+  .bss : ALIGN(0x1000) {
+      _BSS_START_ = .;
+      *(.bss)
+      _BSS_END_ = .;
+  } 
+
+}
diff --git a/userspace/sys/sys.c b/userspace/sys/sys.c
new file mode 100644
index 0000000..7dcfaee
--- /dev/null
+++ b/userspace/sys/sys.c
@@ -0,0 +1,55 @@
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+
+// building binutils required this stubs!
+long sysconf(int name)
+{
+    return 0;
+}
+
+
+mode_t umask(mode_t mask)
+{
+    return mask;
+}
+
+int chmod(const char * path, mode_t mode)
+{
+    return 0;
+}
+
+int fcntl(int fd, int cmd, ...)
+{
+    return -1;
+}
+
+int lstat(const char *path, struct stat *buf)
+{
+    return -1;
+}
+
+char *getwd(char *buf)
+{
+    return buf;
+}
+int access(const char *pathname, int mode)
+{
+    return 0;
+}
+
+int utime(const char *filename, const int *x)
+{
+    return 0;
+}
+
+int rmdir (const  char *pathname)
+{
+    return -1;
+}
+
+int chown(const char *path, uid_t owner, gid_t group)
+{
+    return 0;
+}
diff --git a/userspace/sys/syscalls.c b/userspace/sys/syscalls.c
new file mode 100644
index 0000000..51436fb
--- /dev/null
+++ b/userspace/sys/syscalls.c
@@ -0,0 +1,136 @@
+#include "../kernel/syscalls.h"
+
+/*
+char *__env3[]={0};
+char *__env1[]={"a=10","b=20"};
+char *__env2[]={"dupa=test2"};
+char **environ={__env1,__env2,__env3};
+*/
+
+void _exit(int ret)
+{
+    return syscall(SYSCALL_EXIT,ret,0,0);
+}
+
+// generic syscall interface!
+int syscall(int call, int p1, int p2, int p3)
+{
+	int ebx; // will hold return value;
+
+	asm("pusha");
+
+	// select syscall
+	asm("mov %0, %%eax"::"m"(call)); 
+
+	// pass params
+	asm("mov %0,%%edx"::"m"(p1));
+	asm("mov %0,%%ecx"::"m"(p2));
+	asm("mov %0,%%ebx"::"m"(p3));
+
+	// interrrupt
+	asm("int $0x80");
+
+	// get return value
+        asm("mov %%ebx, %0": "=b" (ebx));
+
+	asm("popa");
+
+	return ebx;
+}
+
+int close(int file) 
+{
+    return syscall(SYSCALL_CLOSE,file,0,0);
+}
+
+int fstat(int file, struct stat *st)
+{
+    return syscall(SYSCALL_FSTAT,file,st,0);
+}
+
+int isatty(int file) 
+{
+    return syscall(SYSCALL_ISATTY,file,0,0);
+}
+
+int lseek(int file, int ptr, int dir) 
+{
+    return syscall(SYSCALL_LSEEK,file,ptr,dir);
+}
+
+int read(int file, char *ptr, int len)
+{
+
+    return syscall(SYSCALL_READ,file,ptr,len);
+}
+
+int readdir(const char *name,fs_dirent  *dirs,int max)
+{
+
+    return syscall(SYSCALL_READDIR,name,dirs,max);
+}
+
+int open(const char *name, int flags, int mode)
+{
+    return syscall(SYSCALL_OPEN,name,flags,mode);
+}
+
+int write(int file, char *ptr, int len) 
+{
+    return syscall(SYSCALL_WRITE,file,ptr,len);
+}
+
+int execve(char *name, char **argv, char **env) 
+{
+    return syscall(SYSCALL_EXECVE,name,argv,env);
+}
+
+uint32_t sbrk(int incr) 
+{
+    return syscall(SYSCALL_SBRK,incr,0,0);
+}
+
+int gettimeofday(struct timeval *tv, void *tz)
+{
+    return syscall(SYSCALL_GETTIMEOFDAY,tv,tz,0);
+}
+
+int fork(void)
+{
+    return syscall(SYSCALL_FORK,0,0,0);
+}
+
+int getpid(void)
+{
+    return syscall(SYSCALL_GETPID,0,0,0);
+}
+
+int kill(int pid, int sig)
+{
+    return syscall(SYSCALL_KILL,pid,sig,0);
+}
+
+int link(char *old, char *ne)
+{
+    return syscall(SYSCALL_LINK,old,ne,0);
+}
+
+int stat(const char *file, struct stat *st)
+{
+    return syscall(SYSCALL_STAT,file,st,0);
+}
+
+int times(struct tms *buf)
+{
+    return syscall(SYSCALL_TIMES,buf,0,0);
+}
+
+int unlink(char *name)
+{
+    return syscall(SYSCALL_UNLINK,name,0,0);
+}
+
+int wait(int *status)
+{
+    return syscall(SYSCALL_WAIT,status,0,0);
+}