micropython/upysh: Add the cp() function and improve ls and rm.

- cp() copies a file. If the target is a directory, the file is copied
  into that directory.  It uses a small buffer, so it's not fast.
- ls uses ilistdir and creates a sorted output with directories listed as
  the first group.
- rm optionally deletes recursive, if the target is a directory.

micropython/upysh/upysh.py

@@ -8,14 +8,22 @@ class LS:
         return ""
 
     def __call__(self, path="."):
-        l = os.listdir(path)
+        l = list(os.ilistdir(path))
         l.sort()
         for f in l:
-            st = os.stat("%s/%s" % (path, f))
-            if st[0] & 0x4000:  # stat.S_IFDIR
-                print("   <dir> %s" % f)
-            else:
-                print("% 8d %s" % (st[6], f))
+            if f[1] == 0x4000:  # stat.S_IFDIR
+                print("    <dir> %s" % f[0])
+        for f in l:
+            if f[1] != 0x4000:
+                if len(f) > 3:
+                    print("% 9d %s" % (f[3], f[0]))
+                else:
+                    print("          %s" % f[0])
+        try:
+            st = os.statvfs(path)
+            print("\n{:,d}k free".format(st[1] * st[3] // 1024))
+        except:
+            pass
 
 
 class PWD:
@@ -34,17 +42,6 @@ class CLEAR:
         return self.__repr__()
 
 
-pwd = PWD()
-ls = LS()
-clear = CLEAR()
-
-cd = os.chdir
-mkdir = os.mkdir
-mv = os.rename
-rm = os.remove
-rmdir = os.rmdir
-
-
 def head(f, n=10):
     with open(f) as f:
         for i in range(n):
@@ -58,6 +55,22 @@ def cat(f):
     head(f, 1 << 30)
 
 
+def cp(s, t):
+    try:
+        if os.stat(t)[0] & 0x4000:  # is directory
+            t = t.rstrip("/") + "/" + s
+    except OSError:
+        pass
+    buf = bytearray(512)
+    buf_mv = memoryview(buf)
+    with open(s, "rb") as s, open(t, "wb") as t:
+        while True:
+            n = s.readinto(buf)
+            if n <= 0:
+                break
+            t.write(buf_mv[:n])
+
+
 def newfile(path):
     print("Type file contents line by line, finish with EOF (Ctrl+D).")
     with open(path, "w") as f:
@@ -70,6 +83,19 @@ def newfile(path):
             f.write("\n")
 
 
+def rm(d, recursive=False):  # Remove file or tree
+    try:
+        if (os.stat(d)[0] & 0x4000) and recursive:  # Dir
+            for f in os.ilistdir(d):
+                if f[0] != "." and f[0] != "..":
+                    rm("/".join((d, f[0])))  # File or Dir
+            os.rmdir(d)
+        else:  # File
+            os.remove(d)
+    except:
+        print("rm of '%s' failed" % d)
+
+
 class Man:
     def __repr__(self):
         return """
@@ -79,12 +105,20 @@ from upysh import *
 To see this help text again, type "man".
 
 upysh commands:
-pwd, cd("new_dir"), ls, ls(...), head(...), cat(...)
-newfile(...), mv("old", "new"), rm(...), mkdir(...), rmdir(...),
-clear
+clear, ls, ls(...), head(...), cat(...), newfile(...)
+cp('src', 'dest'), mv('old', 'new'), rm(...)
+pwd, cd(...), mkdir(...), rmdir(...)
 """
 
 
 man = Man()
+pwd = PWD()
+ls = LS()
+clear = CLEAR()
+
+cd = os.chdir
+mkdir = os.mkdir
+mv = os.rename
+rmdir = os.rmdir
 
 print(man)