os_dep: missing file

1 files changed, 64 insertions, 0 deletions

diff --git a/miasm2/os_dep/common.py b/miasm2/os_dep/common.py
new file mode 100644
index 00000000..83b00ae6
--- /dev/null
+++ b/miasm2/os_dep/common.py
@@ -0,0 +1,64 @@
+from miasm2.jitter.csts import *
+
+def get_str_ansi(jitter, ad_str, max_char=None):
+    l = 0
+    tmp = ad_str
+    while ((max_char is None or l < max_char) and
+        jitter.vm.get_mem(tmp, 1) != "\x00"):
+        tmp += 1
+        l += 1
+    return jitter.vm.get_mem(ad_str, l)
+
+
+def get_str_unic(jitter, ad_str, max_char=None):
+    l = 0
+    tmp = ad_str
+    while ((max_char is None or l < max_char) and
+        jitter.vm.get_mem(tmp, 2) != "\x00\x00"):
+        tmp += 2
+        l += 2
+    s = jitter.vm.get_mem(ad_str, l)
+    # TODO: real unicode decoding
+    s = s[::2]
+    return s
+
+
+def set_str_ansi(s):
+    return s + "\x00"
+
+
+def set_str_unic(s):
+    # TODO: real unicode encoding
+    return "\x00".join(list(s)) + '\x00' * 3
+
+
+
+class heap(object):
+    "Light heap simulation"
+
+    addr = 0x20000000
+    align = 0x1000
+    size = 32
+    mask = (1<< size) - 1
+
+    def next_addr(self, size):
+        """
+        @size: the size to allocate
+        return the future checnk address
+        """
+        ret = self.addr
+        self.addr = (self.addr + size + self.align - 1)
+        self.addr &= self.mask ^ (self.align - 1)
+        return ret
+
+
+    def alloc(self, jitter, size):
+        """
+        @jitter: a jitter instance
+        @size: the size to allocate
+        """
+
+        addr = self.next_addr(size)
+        jitter.vm.add_memory_page(addr, PAGE_READ | PAGE_WRITE, "\x00" * size)
+        return addr
+