Add ftruncate syscall

4 files changed, 22 insertions, 0 deletions

diff --git a/pk/file.c b/pk/file.c
index ad1bde3..ee2f9fd 100644
--- a/pk/file.c
+++ b/pk/file.c
@@ -145,6 +145,11 @@ int file_stat(file_t* f, struct stat* s)
   return frontend_syscall(SYS_fstat, f->kfd, (uintptr_t)s, 0, 0, 0, 0, 0);
 }
 
+int file_truncate(file_t* f, off_t len)
+{
+  return frontend_syscall(SYS_ftruncate, f->kfd, len, 0, 0, 0, 0, 0);
+}
+
 ssize_t file_lseek(file_t* f, size_t ptr, int dir)
 {
   return frontend_syscall(SYS_lseek, f->kfd, ptr, dir, 0, 0, 0, 0);
diff --git a/pk/file.h b/pk/file.h
index 0d942b2..c9f7ce4 100644
--- a/pk/file.h
+++ b/pk/file.h
@@ -31,6 +31,7 @@ ssize_t file_pread(file_t* f, void* buf, size_t n, off_t off);
 ssize_t file_write(file_t* f, const void* buf, size_t n);
 ssize_t file_read(file_t* f, void* buf, size_t n);
 ssize_t file_lseek(file_t* f, size_t ptr, int dir);
+int file_truncate(file_t* f, off_t len);
 int file_stat(file_t* f, struct stat* s);
 int fd_close(int fd);
 
diff --git a/pk/syscall.c b/pk/syscall.c
index e80535b..2d96282 100644
--- a/pk/syscall.c
+++ b/pk/syscall.c
@@ -165,6 +165,20 @@ int sys_fcntl(int fd, int cmd, int arg)
   return r;
 }
 
+int sys_ftruncate(int fd, off_t len)
+{
+  int r = -EBADF;
+  file_t* f = file_get(fd);
+
+  if (f)
+  {
+    r = file_truncate(f, len);
+    file_decref(f);
+  }
+
+  return r;
+}
+
 int sys_dup(int fd)
 {
   int r = -EBADF;
@@ -446,6 +460,7 @@ long do_syscall(long a0, long a1, long a2, long a3, long a4, long a5, unsigned l
     [SYS_writev] = sys_writev,
     [SYS_faccessat] = sys_faccessat,
     [SYS_fcntl] = sys_fcntl,
+    [SYS_ftruncate] = sys_ftruncate,
     [SYS_getdents] = sys_getdents,
     [SYS_dup] = sys_dup,
     [SYS_readlinkat] = sys_stub_nosys,
diff --git a/pk/syscall.h b/pk/syscall.h
index 1619e3e..bed30e9 100644
--- a/pk/syscall.h
+++ b/pk/syscall.h
@@ -38,6 +38,7 @@
 #define SYS_gettimeofday 169
 #define SYS_times 153
 #define SYS_fcntl 25
+#define SYS_ftruncate 46
 #define SYS_getdents 61
 #define SYS_dup 23
 #define SYS_readlinkat 78