Prepare userland shell

Makefile

@@ -32,11 +32,14 @@ programs/loop/a.out: force_look
 programs/keyboard/a.out: force_look
 	cd programs/keyboard; ${MAKE} a.out
 
+programs/tsh/tsh: force_look
+	cd programs/tsh; ${MAKE} tsh
+
 hdd.img:
 	dd if=/dev/zero of=hdd.img bs=516096c count=1000
 	(echo n; echo p; echo 1; echo ""; echo ""; echo t; echo c; echo a; echo 1; echo w;) | sudo fdisk -u -C1000 -S63 -H16 hdd.img
 
-thor.flp: hdd.img bootloader/stage1.bin bootloader/stage2.bin kernel/kernel.bin programs/one/a.out programs/hello/a.out programs/long/a.out programs/loop/a.out programs/longone/a.out programs/longtwo/a.out programs/keyboard/a.out
+thor.flp: hdd.img bootloader/stage1.bin bootloader/stage2.bin kernel/kernel.bin programs/one/a.out programs/hello/a.out programs/long/a.out programs/loop/a.out programs/longone/a.out programs/longtwo/a.out programs/keyboard/a.out programs/tsh/tsh
 	mkdir -p mnt/fake/
 	dd if=bootloader/stage1.bin of=hdd.img conv=notrunc
 	dd if=bootloader/stage2.bin of=hdd.img seek=1 conv=notrunc
@@ -51,6 +54,7 @@ thor.flp: hdd.img bootloader/stage1.bin bootloader/stage2.bin kernel/kernel.bin
 	sudo /bin/cp programs/longtwo/a.out mnt/fake/longtwo
 	sudo /bin/cp programs/loop/a.out mnt/fake/loop
 	sudo /bin/cp programs/keyboard/a.out mnt/fake/keyboard
+	sudo /bin/cp programs/tsh/tsh mnt/fake/tsh
 	sleep 0.1
 	sudo /bin/umount mnt/fake/
 	sudo /sbin/losetup -d /dev/loop0

programs/tsh/Makefile

@@ -0,0 +1,15 @@
+.PHONY: default clean
+
+default: tsh
+
+include ../../cpp.mk
+
+%.cpp.o: src/%.cpp
+	$(CC) $(PROGRAM_FLAGS) -mcmodel=large $(CPP_FLAGS_64) $(WARNING_FLAGS) -c $< -o $@
+
+tsh: main.cpp.o
+	$(CC) $(PROGRAM_LINK_FLAGS) -mcmodel=small -fPIC $(CPP_FLAGS_64) -o tsh main.cpp.o
+
+clean:
+	rm -f *.cpp.o
+	rm -rf tsh

programs/tsh/src/main.cpp

@@ -0,0 +1,27 @@
+//=======================================================================
+// Copyright Baptiste Wicht 2013-2014.
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt)
+//=======================================================================
+
+#include <print.hpp>
+#include <system.hpp>
+#include <string.hpp>
+
+int main(){
+    char input_buffer[64];
+
+    while(true){
+        for(int i = 0; i < 10; ++i){
+            auto c = read_input(input_buffer, 63);
+            input_buffer[c] = '\0';
+
+            if(str_equals(input_buffer, "exit")){
+                exit(0);
+            } else {
+                print_line("Unknown command");
+            }
+        }
+    }
+}

userlib/include/string.hpp

@@ -0,0 +1,40 @@
+//=======================================================================
+// Copyright Baptiste Wicht 2013-2014.
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt)
+//=======================================================================
+
+#ifndef USERLIB_STRING_H
+#define USERLIB_STRING_H
+
+int str_compare(const char *s1, const char *s2){
+    while (*s1 != '\0') {
+        if (*s2 == '\0'){
+            return  1;
+        }
+
+        if (*s2 > *s1){
+            return -1;
+        }
+
+        if (*s1 > *s2){
+            return  1;
+        }
+
+        s1++;
+        s2++;
+    }
+
+    if (*s2 != '\0'){
+        return -1;
+    }
+
+    return 0;
+}
+
+bool str_equals(const char* s1, const char* s2){
+    return str_compare(s1, s2) == 0;
+}
+
+#endif