1 files changed, 57 insertions, 0 deletions
diff --git a/chapter22/src/main/smp/sys.smp b/chapter22/src/main/smp/sys.smp
new file mode 100644
index 00000000..ede08d63
--- /dev/null
+++ b/chapter22/src/main/smp/sys.smp
@@ -0,0 +1,57 @@
+// -*- mode: java;  -*-
+
+// top-level default import
+struct sys {
+    // libc bindings
+    /** https://www.man7.org/linux/man-pages/man2/<libc call>.2.html */
+    struct libc {
+        i32 errno = "C";
+        // fd  buf len -> len
+        {  i32 i64 u32 -> u32 } write = "C";
+        // fd  buf len -> len
+        {  i32 i64 u32 -> u32 } read = "C";
+        // status
+        {  i32 -> i32 } _exit = "C";
+        // addr len prot flags fd  off -> void*
+        {  i64  i64 i32  i32   i32 i32 -> i64 } mmap = "C";
+        // mmap flags
+        i32 PROT_EXEC = 4;
+        i32 PROT_READ = 1;
+        i32 PROT_WRITE= 2;
+        i32 PROT_NONE = 0;
+        i32 MAP_PRIVATE = 2;
+        i32 MAP_ANON = 32;
+    };
+    struct ary {
+        val copy = { u8[] dst, int doff, u8[~] src, int soff, int len ->
+            for( int i=0; i<len; i++ )
+                dst[i+doff] = src[i+soff];
+            return dst;
+        };
+    };
+    struct io {
+        // Print string to stdout
+        val p = { u8[~] str ->
+            i64 ptr = str;  // cast array base to i64
+            return sys.libc.write(1,ptr,str#);
+        };
+
+        // Return stdin as a u8[]
+        val stdin = { ->
+            var buf = new u8[8*1024];
+            i64 ptr = buf;
+            int len = 0;
+            while( true ) {
+                int rez = sys.libc.read(0,ptr,buf#);
+                if( rez < 0 ) sys.libc._exit(sys.libc.errno);
+                len += rez;
+                if( rez < buf# )
+                    break;
+                sys.libc._exit(-2); // Need to implement
+            }
+            // Compress
+            var dst = new u8[len];
+            return sys.ary.copy(dst,0,buf,0,len);
+        };
+    };
+};