GLK: GLULXE: Added vm methods

4 files changed, 391 insertions, 23 deletions

diff --git a/engines/glk/glulxe/glulxe.h b/engines/glk/glulxe/glulxe.h
index 4044074e37..f7684f1830 100644
--- a/engines/glk/glulxe/glulxe.h
+++ b/engines/glk/glulxe/glulxe.h
@@ -38,7 +38,11 @@ typedef void (Glulxe::*UnicharHandler)(uint);
  * Glulxe game interpreter
  */
 class Glulxe : public GlkAPI {
-public:
+private:
+	/**
+	 * \defgroup vm fields
+	 * @{
+	 */
 	CharHandler stream_char_handler;
 	UnicharHandler stream_unichar_handler, glkio_unichar_han_ptr;
 
@@ -67,6 +71,8 @@ public:
 	uint protectstart, protectend;
 	uint prevpc;
 
+	/**@}*/
+
 	/**
 	 * \defgroup accel fields
 	 * @{
@@ -342,7 +348,7 @@ protected:
 	 * @{
 	 */
 
-	void stream_setup_unichar(void);
+	void stream_setup_unichar();
 
 	void nopio_char_han(unsigned char ch);
 	void filio_char_han(unsigned char ch);
@@ -385,8 +391,6 @@ public:
 	 * \defgroup Main access methods
 	 * @{
 	 */
-	void set_library_start_hook(void(*)(void));
-	void set_library_autorestore_hook(void(*)(void));
 
 	/**
 	 * Display an error in the error window, and then exit.
@@ -414,8 +418,6 @@ public:
 	  */
 	bool is_gamefile_valid();
 
-	int locate_gamefile(int isblorb);
-	
 	/**@}*/
 
 	/**
@@ -423,13 +425,53 @@ public:
 	 * @{
 	 */
 
-	void setup_vm(void);
-	void finalize_vm(void);
-	void vm_restart(void);
-	uint change_memsize(uint newlen, int internal);
+	 /**
+	  * Read in the game file and build the machine, allocating all the memory necessary.
+	 */
+	void setup_vm();
+
+	/**
+	 * Deallocate all the memory and shut down the machine.
+	 */
+	void finalize_vm();
+	
+	/**
+	 * Put the VM into a state where it's ready to begin executing the game. This is called
+	 * both at startup time, and when the machine performs a "restart" opcode.
+	 */
+	void vm_restart();
+
+	/**
+	 * Change the size of the memory map. This may not be available at all; #define FIXED_MEMSIZE
+	 * if you want the interpreter to unconditionally refuse. The internal flag should be true only
+	 * when the heap-allocation system is calling. Returns 0 for success; otherwise, the operation failed.
+	 */
+	uint change_memsize(uint newlen, bool internal);
+	
+	/**
+	 * If addr is 0, pop N arguments off the stack, and put them in an array. If non-0, take N arguments
+	 * from that main memory address instead. This has to dynamically allocate if there are more than
+	 * 32 arguments, but that shouldn't be a problem.
+	 */
 	uint *pop_arguments(uint count, uint addr);
+	
+	/**
+	 * Make sure that count bytes beginning with addr all fall within the current memory map.
+	 * This is called at every memory (read) access if VERIFY_MEMORY_ACCESS is defined in the header file.
+	*/
 	void verify_address(uint addr, uint count);
+
+	/**
+	 * Make sure that count bytes beginning with addr all fall within RAM. This is called at every memory
+	 * write if VERIFY_MEMORY_ACCESS is defined in the header file.
+	*/
 	void verify_address_write(uint addr, uint count);
+
+	/**
+	 * Make sure that an array of count elements (size bytes each), starting at addr, does not fall
+	 * outside the memory map. This goes to some trouble that verify_address() does not, because we need
+	 * to be wary of lengths near -- or beyond -- 0x7FFFFFFF.
+	 */
 	void verify_array_addresses(uint addr, uint count, uint size);
 
 	/**@}*/
@@ -527,7 +569,7 @@ public:
 	 * Set the heap state to inactive, and free the block lists. This is called when the game
 	 * starts or restarts.
 	 */
-	void heap_clear(void);
+	void heap_clear();
 
 	/**
 	 * Returns whether the heap is active.
@@ -637,7 +679,7 @@ public:
 	void *glulx_realloc(void *ptr, uint len);
 	void glulx_free(void *ptr);
 	void glulx_setrandom(uint seed);
-	uint glulx_random(void);
+	uint glulx_random();
 	void glulx_sort(void *addr, int count, int size,
 		int(*comparefunc)(void *p1, void *p2));
 
@@ -723,16 +765,16 @@ public:
 	 */
 
 	void setup_profile(strid_t stream, char *filename);
-	int init_profile(void);
+	int init_profile();
 	void profile_set_call_counts(int flag);
 #if VM_PROFILING
 	uint profile_opcount;
 #define profile_tick() (profile_opcount++)
-	int profile_profiling_active(void);
+	int profile_profiling_active();
 	void profile_in(uint addr, uint stackuse, int accel);
 	void profile_out(uint stackuse);
 	void profile_fail(char *reason);
-	void profile_quit(void);
+	void profile_quit();
 #else /* VM_PROFILING */
 #define profile_tick()         (0)
 #define profile_profiling_active()         (0)
@@ -751,15 +793,15 @@ public:
 	void debugger_set_start_trap(int flag);
 	void debugger_set_quit_trap(int flag);
 	void debugger_set_crash_trap(int flag);
-	void debugger_check_story_file(void);
-	void debugger_setup_start_state(void);
-	int debugger_ever_invoked(void);
+	void debugger_check_story_file();
+	void debugger_setup_start_state();
+	int debugger_ever_invoked();
 	int debugger_cmd_handler(char *cmd);
 	void debugger_cycle_handler(int cycle);
 	void debugger_check_func_breakpoint(uint addr);
 	void debugger_block_and_debug(char *msg);
 	void debugger_handle_crash(char *msg);
-	void debugger_handle_quit(void);
+	void debugger_handle_quit();
 #else /* VM_DEBUGGER */
 #define debugger_tick()              (0)
 #define debugger_check_story_file()  (0)
@@ -805,7 +847,7 @@ public:
 	   /* #define FLOAT_NOT_NATIVE (1) */
 
 	   /* float.c */
-	int init_float(void);
+	int init_float();
 	uint encode_float(gfloat32 val);
 	gfloat32 decode_float(uint val);
 
@@ -884,7 +926,7 @@ public:
 	/**
 	 * Get the current table address.
 	 */
-	uint stream_get_table(void);
+	uint stream_get_table();
 
 	/**
 	 * Set the current table address, and rebuild decoding cache.
diff --git a/engines/glk/glulxe/serial.cpp b/engines/glk/glulxe/serial.cpp
index 66464e80f9..6d662166c4 100644
--- a/engines/glk/glulxe/serial.cpp
+++ b/engines/glk/glulxe/serial.cpp
@@ -517,7 +517,7 @@ int Glulxe::write_buffer(dest_t *dest, const byte *ptr, uint len) {
   return 0;
 }
 
-int Glulxe::read_buffer(dest_t *dest, unsigned char *ptr, uint len) {
+int Glulxe::read_buffer(dest_t *dest, byte *ptr, uint len) {
   uint newlen;
 
   if (dest->ismem) {
@@ -546,7 +546,7 @@ int Glulxe::write_short(dest_t *dest, uint16 val) {
   return write_buffer(dest, buf, 2);
 }
 
-int Glulxe::write_byte(dest_t *dest, unsigned char val) {
+int Glulxe::write_byte(dest_t *dest, byte val) {
   return write_buffer(dest, &val, 1);
 }
 
diff --git a/engines/glk/glulxe/vm.cpp b/engines/glk/glulxe/vm.cpp
new file mode 100644
index 0000000000..f332c92248
--- /dev/null
+++ b/engines/glk/glulxe/vm.cpp
@@ -0,0 +1,325 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#include "engines/glk/glulxe/glulxe.h"
+
+namespace Glk {
+namespace Glulxe {
+
+void Glulxe::setup_vm() {
+  unsigned char buf[4 * 7];
+  int res;
+
+  pc = 0; /* Clear this, so that error messages are cleaner. */
+  prevpc = 0;
+
+  /* Read in all the size constants from the game file header. */
+
+  stream_char_handler = NULL;
+  stream_unichar_handler = NULL;
+
+  glk_stream_set_position(gamefile, gamefile_start+8, seekmode_Start);
+  res = glk_get_buffer_stream(gamefile, (char *)buf, 4 * 7);
+  if (res != 4 * 7) {
+    fatal_error("The game file header is too short.");
+  }
+  
+  ramstart = Read4(buf+0);
+  endgamefile = Read4(buf+4);
+  origendmem = Read4(buf+8);
+  stacksize = Read4(buf+12);
+  startfuncaddr = Read4(buf+16);
+  origstringtable = Read4(buf+20);
+  checksum = Read4(buf+24);
+
+  /* Set the protection range to (0, 0), meaning "off". */
+  protectstart = 0;
+  protectend = 0;
+
+  /* Do a few sanity checks. */
+
+  if ((ramstart & 0xFF)
+    || (endgamefile & 0xFF) 
+    || (origendmem & 0xFF)
+    || (stacksize & 0xFF)) {
+    nonfatal_warning("One of the segment boundaries in the header is not "
+      "256-byte aligned.");
+  }
+
+  if (endgamefile != gamefile_len) {
+    nonfatal_warning("The gamefile length does not match the header "
+      "endgamefile length.");
+  }
+
+  if (ramstart < 0x100 || endgamefile < ramstart || origendmem < endgamefile) {
+    fatal_error("The segment boundaries in the header are in an impossible "
+      "order.");
+  }
+  if (stacksize < 0x100) {
+    fatal_error("The stack size in the header is too small.");
+  }
+  
+  /* Allocate main memory and the stack. This is where memory allocation
+     errors are most likely to occur. */
+  endmem = origendmem;
+  memmap = (unsigned char *)glulx_malloc(origendmem);
+  if (!memmap) {
+    fatal_error("Unable to allocate Glulx memory space.");
+  }
+  stack = (unsigned char *)glulx_malloc(stacksize);
+  if (!stack) {
+    glulx_free(memmap);
+    memmap = NULL;
+    fatal_error("Unable to allocate Glulx stack space.");
+  }
+  stringtable = 0;
+
+  /* Initialize various other things in the terp. */
+  init_operands(); 
+  init_serial();
+
+  /* Set up the initial machine state. */
+  vm_restart();
+
+  /* If the debugger is compiled in, check that the debug data matches
+     the game. (This only prints warnings for mismatch.) */
+  debugger_check_story_file();
+  /* Also, set up any start-time debugger state. This may do a block-
+     and-debug, if the user has requested that. */
+  debugger_setup_start_state();
+}
+
+void Glulxe::finalize_vm() {
+  stream_set_table(0);
+
+  if (memmap) {
+    glulx_free(memmap);
+    memmap = NULL;
+  }
+  if (stack) {
+    glulx_free(stack);
+    stack = NULL;
+  }
+
+  final_serial();
+}
+
+void Glulxe::vm_restart() {
+  uint lx;
+  int res;
+  int bufpos;
+  char buf[0x100];
+
+  /* Deactivate the heap (if it was active). */
+  heap_clear();
+
+  /* Reset memory to the original size. */
+  lx = change_memsize(origendmem, false);
+  if (lx)
+    fatal_error("Memory could not be reset to its original size.");
+
+  /* Load in all of main memory. We do this in 256-byte chunks, because
+     why rely on OS stream buffering? */
+  glk_stream_set_position(gamefile, gamefile_start, seekmode_Start);
+  bufpos = 0x100;
+
+  for (lx=0; lx<endgamefile; lx++) {
+    if (bufpos >= 0x100) {
+      int count = glk_get_buffer_stream(gamefile, buf, 0x100);
+      if (count != 0x100) {
+        fatal_error("The game file ended unexpectedly.");
+      }
+      bufpos = 0;
+    }
+
+    res = buf[bufpos++];
+    if (lx >= protectstart && lx < protectend)
+      continue;
+    memmap[lx] = res;
+  }
+  for (lx=endgamefile; lx<origendmem; lx++) {
+    memmap[lx] = 0;
+  }
+
+  /* Reset all the registers */
+  stackptr = 0;
+  frameptr = 0;
+  pc = 0;
+  prevpc = 0;
+  stream_set_iosys(0, 0);
+  stream_set_table(origstringtable);
+  valstackbase = 0;
+  localsbase = 0;
+
+  /* Note that we do not reset the protection range. */
+
+  /* Push the first function call. (No arguments.) */
+  enter_function(startfuncaddr, 0, NULL);
+
+  /* We're now ready to execute. */
+}
+
+uint Glulxe::change_memsize(uint newlen, bool internal) {
+  uint lx;
+  unsigned char *newmemmap;
+
+  if (newlen == endmem)
+    return 0;
+
+#ifdef FIXED_MEMSIZE
+  return 1;
+#else /* FIXED_MEMSIZE */
+
+  if ((!internal) && heap_is_active())
+    fatal_error("Cannot resize Glulx memory space while heap is active.");
+
+  if (newlen < origendmem)
+    fatal_error("Cannot resize Glulx memory space smaller than it started.");
+
+  if (newlen & 0xFF)
+    fatal_error("Can only resize Glulx memory space to a 256-byte boundary.");
+  
+  newmemmap = (unsigned char *)glulx_realloc(memmap, newlen);
+  if (!newmemmap) {
+    /* The old block is still in place, unchanged. */
+    return 1;
+  }
+  memmap = newmemmap;
+
+  if (newlen > endmem) {
+    for (lx=endmem; lx<newlen; lx++) {
+      memmap[lx] = 0;
+    }
+  }
+
+  endmem = newlen;
+
+  return 0;
+
+#endif /* FIXED_MEMSIZE */
+}
+
+uint *Glulxe::pop_arguments(uint count, uint addr) {
+  int ix;
+  uint argptr;
+  uint *array;
+
+  #define MAXARGS (32)
+  static uint statarray[MAXARGS];
+  static uint *dynarray = NULL;
+  static uint dynarray_size = 0;
+
+  if (count == 0)
+    return NULL;
+
+  if (count <= MAXARGS) {
+    /* Store in the static array. */
+    array = statarray;
+  }
+  else {
+    if (!dynarray) {
+      dynarray_size = count+8;
+      dynarray = (uint *)glulx_malloc(sizeof(uint) * dynarray_size);
+      if (!dynarray)
+        fatal_error("Unable to allocate function arguments.");
+      array = dynarray;
+    }
+    else {
+      if (dynarray_size >= count) {
+        /* It fits. */
+        array = dynarray;
+      }
+      else {
+        dynarray_size = count+8;
+        dynarray = (uint *)glulx_realloc(dynarray, sizeof(uint) * dynarray_size);
+        if (!dynarray)
+          fatal_error("Unable to reallocate function arguments.");
+        array = dynarray;
+      }
+    }
+  }
+
+  if (!addr) {
+    if (stackptr < valstackbase+4*count) 
+      fatal_error("Stack underflow in arguments.");
+    stackptr -= 4*count;
+    for (ix=0; ix<count; ix++) {
+      argptr = stackptr+4*((count-1)-ix);
+      array[ix] = Stk4(argptr);
+    }
+  }
+  else {
+    for (ix=0; ix<count; ix++) {
+      array[ix] = Mem4(addr);
+      addr += 4;
+    }
+  }
+
+  return array;
+}
+
+void Glulxe::verify_address(uint addr, uint count) {
+  if (addr >= endmem)
+    fatal_error_i("Memory access out of range", addr);
+  if (count > 1) {
+    addr += (count-1);
+    if (addr >= endmem)
+      fatal_error_i("Memory access out of range", addr);
+  }
+}
+
+void Glulxe::verify_address_write(uint addr, uint count) {
+  if (addr < ramstart)
+    fatal_error_i("Memory write to read-only address", addr);
+  if (addr >= endmem)
+    fatal_error_i("Memory access out of range", addr);
+  if (count > 1) {
+    addr += (count-1);
+    if (addr >= endmem)
+      fatal_error_i("Memory access out of range", addr);
+  }
+}
+
+void Glulxe::verify_array_addresses(uint addr, uint count, uint size) {
+  uint bytecount;
+  if (addr >= endmem)
+    fatal_error_i("Memory access out of range", addr);
+
+  if (count == 0)
+    return;
+  bytecount = count*size;
+
+  /* If just multiplying by the element size overflows, we have trouble. */
+  if (bytecount < count)
+    fatal_error_i("Memory access way too long", addr);
+
+  /* If the byte length by itself is too long, or if its end overflows,
+     we have trouble. */
+  if (bytecount > endmem || addr+bytecount < addr)
+    fatal_error_i("Memory access much too long", addr);
+  /* The simple length test. */
+  if (addr+bytecount > endmem)
+    fatal_error_i("Memory access too long", addr);
+}
+
+} // End of namespace Glulxe
+} // End of namespace Glk
diff --git a/engines/glk/module.mk b/engines/glk/module.mk
index 247f1d837e..be66cafd41 100644
--- a/engines/glk/module.mk
+++ b/engines/glk/module.mk
@@ -70,6 +70,7 @@ MODULE_OBJS := \
 	glulxe/search.o \
 	glulxe/serial.o \
 	glulxe/string.o \
+	glulxe/vm.o \
 	magnetic/detection.o \
 	magnetic/magnetic.o \
 	scott/detection.o \