-void munge_w(const void *arg0 __unused, void *args);
-void munge_ww(const void *arg0 __unused, void *args);
-void munge_www(const void *arg0 __unused, void *args);
-void munge_wwww(const void *arg0 __unused, void *args);
-void munge_wwwww(const void *arg0 __unused, void *args);
-void munge_wwwwww(const void *arg0 __unused, void *args);
-void munge_wwwwwww(const void *arg0 __unused, void *args);
-void munge_wwwwwwww(const void *arg0 __unused, void *args);
-void munge_wl(const void *arg0 __unused, void *args);
-void munge_wwl(const void *arg0 __unused, void *args);
-void munge_wwlw(const void *arg0 __unused, void *args);
-void munge_wwlll(const void *arg0 __unused, void *args);
-void munge_wwllww(const void *arg0 __unused, void *args);
-void munge_wlw(const void *arg0 __unused, void *args);
-void munge_wlwwwll(const void *arg0 __unused, void *args);
-void munge_wlwwwllw(const void *arg0 __unused, void *args);
-void munge_wlwwlwlw(const void *arg0 __unused, void *args);
-void munge_wll(const void *arg0 __unused, void *args);
-void munge_wllww(const void *arg0 __unused, void *args);
-void munge_wlll(const void *arg0 __unused, void *args);
-void munge_wllwwll(const void *arg0 __unused, void *args);
-void munge_wwwlw(const void *arg0 __unused, void *args);
-void munge_wwwlww(const void *arg0 __unused, void *args);
-void munge_wwwl(const void *arg0 __unused, void *args);
-void munge_wwwwlw(const void *arg0 __unused, void *args);
-void munge_wwwwl(const void *arg0 __unused, void *args);
-void munge_wwwwwl(const void *arg0 __unused, void *args);
-void munge_wwwwwlww(const void *arg0 __unused, void *args);
-void munge_wwwwwllw(const void *arg0 __unused, void *args);
-void munge_wwwwwlll(const void *arg0 __unused, void *args);
-void munge_wwwwwwl(const void *arg0 __unused, void *args);
-void munge_wwwwwwlw(const void *arg0 __unused, void *args);
-void munge_wwwwwwll(const void *arg0 __unused, void *args);
-void munge_wsw(const void *arg0 __unused, void *args);
-void munge_wws(const void *arg0 __unused, void *args);
-void munge_wwwsw(const void *arg0 __unused, void *args);
-void munge_llllll(const void *arg0 __unused, void *args __unused);
-void munge_l(const void *arg0 __unused, void *args __unused);
-void munge_ll(const void *arg0 __unused, void *args __unused);
-void munge_lw(const void *arg0 __unused, void *args);
-void munge_lwww(const void *arg0 __unused, void *args);
-void munge_wwlwww(const void *arg0 __unused, void *args);
+
+#ifndef __MUNGE_H__
+#define __MUNGE_H__
+
+/*
+ * Syscall argument mungers.
+ *
+ * The data to be munged has been explicitly copied in to the argument
+ * area, and will be munged in place in the uu_arg[] array. These
+ * mungers are for 32-bit app's syscalls, since 64-bit args are copied
+ * from the save area to the uu_args in the order the
+ * syscall ABI calls for.
+ *
+ * The issue is that the incoming args are 32-bit, but we must expand
+ * them in place into 64-bit args, as if they were from a 64-bit process.
+ *
+ * There are several functions in this file with the following prototype
+ *
+ * void munge_XXXX(void *uu_args);
+ *
+ * The name of the function encodes the number and type of the parameters,
+ * as follows:
+ *
+ * w = a 32-bit value such as an int or a 32-bit ptr, that does not
+ * require sign extension. These are handled by zeroing a word
+ * of output, and copying a word from input to output.
+ *
+ * s = a 32-bit value such as a long, which must be sign-extended to
+ * a 64-bit long-long in the uu_args. These are handled by
+ * loading a word of input and sign extending it to a double,
+ * and storing two words of output.
+ *
+ * l = a 64-bit long-long. These are handled by copying two words
+ * of input to the output.
+ *
+ * For example, "munge_wls" takes a word, a long-long, and a word. This
+ * takes four words in the uu_arg[] area: the first word is in one, the
+ * long-long takes two, and the final word is in the fourth. We store six
+ * words: the low word is left in place, followed by a 0, followed by the
+ * two words of the long-long, followed by the low word and the sign extended
+ * high word of the preceeding low word.
+ *
+ * Because this is an in-place modification, we actually start at the end
+ * of uu_arg[] and work our way back to the beginning of the array.
+ */
+
+void munge_w(void *args);
+void munge_ww(void *args);
+void munge_www(void *args);
+void munge_wwww(void *args);
+void munge_wwwww(void *args);
+void munge_wwwwww(void *args);
+void munge_wwwwwww(void *args);
+void munge_wwwwwwww(void *args);
+void munge_wl(void *args);
+void munge_wwl(void *args);
+void munge_wwlw(void *args);
+void munge_wwlll(void *args);
+void munge_wwllww(void *args);
+void munge_wlw(void *args);
+void munge_wlww(void *args);
+void munge_wlwwwl(void *args);
+void munge_wlwwwll(void *args);
+void munge_wlwwwllw(void *args);
+void munge_wlwwlwlw(void *args);
+void munge_wll(void *args);
+void munge_wllww(void *args);
+void munge_wlll(void *args);
+void munge_wllll(void *args);
+void munge_wllwwll(void *args);
+void munge_wwwlw(void *args);
+void munge_wwwlww(void *args);
+void munge_wwwl(void *args);
+void munge_wwwwlw(void *args);
+void munge_wwwwl(void *args);
+void munge_wwwwwl(void *args);
+void munge_wwwwwlww(void *args);
+void munge_wwwwwllw(void *args);
+void munge_wwwwwlll(void *args);
+void munge_wwwwwwl(void *args);
+void munge_wwwwwwlw(void *args);
+void munge_wwwwwwll(void *args);
+void munge_wsw(void *args);
+void munge_wws(void *args);
+void munge_wwws(void *args);
+void munge_wwwsw(void *args);
+void munge_llllll(void *args);
+void munge_l(void *args);
+void munge_ll(void *args);
+void munge_lw(void *args);
+void munge_lwww(void *args);
+void munge_wwlww(void *args);
+void munge_wwlwww(void *args);
+void munge_wwlwwwl(void *args);
projects / apple / xnu.git / blobdiff