--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/parser.cc Mon Jan 13 23:44:15 2014 +0200
@@ -0,0 +1,1450 @@
+/*
+ Copyright (c) 2012-2014, Santeri Piippo
+ All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are met:
+
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+
+ * Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in the
+ documentation and/or other materials provided with the distribution.
+
+ * Neither the name of the <organization> nor the
+ names of its contributors may be used to endorse or promote products
+ derived from this software without specific prior written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
+ DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include "object_writer.h"
+#include "parser.h"
+#include "events.h"
+#include "commands.h"
+#include "stringtable.h"
+#include "variables.h"
+#include "containers.h"
+#include "lexer.h"
+
+#define SCOPE(n) scopestack[g_ScopeCursor - n]
+
+// TODO: make these static
+int g_NumStates = 0;
+int g_NumEvents = 0;
+parsermode_e g_CurMode = MODE_TOPLEVEL;
+string g_CurState = "";
+bool g_stateSpawnDefined = false;
+bool g_GotMainLoop = false;
+int g_ScopeCursor = 0;
+data_buffer* g_IfExpression = null;
+bool g_CanElse = false;
+static string* g_undefined_labels[MAX_MARKS]; // TODO: make a list
+list<constant_info> g_ConstInfo;
+
+static botscript_parser* g_current_parser = null;
+
+// ============================================================================
+//
+botscript_parser::botscript_parser() :
+ m_lx (new lexer) {}
+
+// ============================================================================
+//
+botscript_parser::~botscript_parser()
+{
+ delete m_lx;
+}
+
+// ============================================================================
+//
+void botscript_parser::check_toplevel()
+{
+ if (g_CurMode != MODE_TOPLEVEL)
+ error ("%1-statements may only be defined at top level!", token_string().chars());
+}
+
+// ============================================================================
+//
+void botscript_parser::check_not_toplevel()
+{
+ if (g_CurMode == MODE_TOPLEVEL)
+ error ("%1-statements must not be defined at top level!", token_string().chars());
+}
+
+// ============================================================================
+// Main parser code. Begins read of the script file, checks the syntax of it
+// and writes the data to the object file via Objwriter - which also takes care
+// of necessary buffering so stuff is written in the correct order.
+void botscript_parser::parse_botscript (string file_name, object_writer* w)
+{
+ m_writer = w;
+
+ // Lex and preprocess the file
+ m_lx->process_file (file_name);
+
+ // Zero the entire block stack first
+ // TODO: this shouldn't be necessary
+ for (int i = 0; i < MAX_SCOPE; i++)
+ ZERO (scopestack[i]);
+
+ for (int i = 0; i < MAX_MARKS; i++)
+ g_undefined_labels[i] = null;
+
+ while (m_lx->get_next())
+ {
+ // Check if else is potentically valid
+ if (token_is (tk_else) && !g_CanElse)
+ error ("else without preceding if");
+
+ if (!token_is (tk_else))
+ g_CanElse = false;
+
+ switch (m_lx->get_token()->type)
+ {
+ case tk_state:
+ parse_state_block();
+ break;
+
+ case tk_event:
+ parse_event_block();
+ break;
+
+ case tk_mainloop:
+ parse_mainloop();
+ break;
+
+ case tk_onenter:
+ case tk_onexit:
+ parse_on_enter_exit();
+ break;
+
+ case tk_int:
+ case tk_str:
+ case tk_void:
+ parse_variable_declaration();
+ break;
+
+ case tk_goto:
+ parse_goto();
+ break;
+
+ case tk_if:
+ parse_if();
+ break;
+
+ case tk_else:
+ parse_else();
+ break;
+
+ case tk_while:
+ parse_while_block();
+ break;
+
+ case tk_for:
+ parse_for_block();
+ break;
+
+ case tk_do:
+ parse_do_block();
+ break;
+
+ case tk_switch:
+ parse_switch_block();
+ break;
+
+ case tk_case:
+ parse_switch_case();
+ break;
+
+ case tk_default:
+ parse_switch_default();
+ break;
+
+ case tk_break:
+ parse_break();
+ break;
+
+ case tk_continue:
+ parse_continue();
+ break;
+
+ case tk_brace_end:
+ parse_block_end();
+ break;
+
+ case tk_const:
+ parse_const();
+ break;
+
+ default:
+ {
+ // Check for labels
+ lexer::token next;
+
+ if (token_is (tk_symbol) &&
+ m_lx->peek_next (&next) &&
+ next.type == tk_colon)
+ {
+ parse_label();
+ break;
+ }
+
+ // Check if it's a command
+ command_info* comm = find_command_by_name (token_string());
+
+ if (comm)
+ {
+ m_writer->get_current_buffer()->merge (ParseCommand (comm));
+ m_lx->must_get_next (tk_semicolon);
+ continue;
+ }
+
+ // If nothing else, parse it as a statement
+ data_buffer* b = parse_statement (w);
+
+ if (!b)
+ error ("unknown token `%1`", token_string());
+
+ m_writer->write_buffer (b);
+ m_lx->must_get_next (tk_semicolon);
+ }
+ break;
+ }
+ }
+
+ // ===============================================================================
+ // Script file ended. Do some last checks and write the last things to main buffer
+ if (g_CurMode != MODE_TOPLEVEL)
+ error ("script did not end at top level; a `}` is missing somewhere");
+
+ // stateSpawn must be defined!
+ if (!g_stateSpawnDefined)
+ error ("script must have a state named `stateSpawn`!");
+
+ for (int i = 0; i < MAX_MARKS; i++)
+ if (g_undefined_labels[i])
+ error ("label `%s` is referenced via `goto` but isn't defined\n", g_undefined_labels[i]->chars());
+
+ // Dump the last state's onenter and mainloop
+ m_writer->write_member_buffers();
+
+ // String table
+ m_writer->write_string_table();
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_state_block()
+{
+ check_toplevel();
+ m_lx->must_get_next (tk_string);
+ string statename = token_string();
+
+ // State name must be a word.
+ if (statename.first (" ") != -1)
+ error ("state name must be a single word, got `%1`", statename);
+
+ // stateSpawn is special - it *must* be defined. If we
+ // encountered it, then mark down that we have it.
+ if (-statename == "statespawn")
+ g_stateSpawnDefined = true;
+
+ // Must end in a colon
+ m_lx->must_get_next (tk_colon);
+
+ // write the previous state's onenter and
+ // mainloop buffers to file now
+ if (g_CurState.is_empty() == false)
+ m_writer->write_member_buffers();
+
+ m_writer->write (dh_state_name);
+ m_writer->write_string (statename);
+ m_writer->write (dh_state_index);
+ m_writer->write (g_NumStates);
+
+ g_NumStates++;
+ g_CurState = statename;
+ g_GotMainLoop = false;
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_event_block()
+{
+ check_toplevel();
+ m_lx->must_get_next (tk_string);
+
+ event_info* e = find_event_by_name (token_string());
+
+ if (!e)
+ error ("bad event, got `%1`\n", token_string());
+
+ m_lx->must_get_next (tk_brace_start);
+ g_CurMode = MODE_EVENT;
+ m_writer->write (dh_event);
+ m_writer->write (e->number);
+ g_NumEvents++;
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_mainloop()
+{
+ check_toplevel();
+ m_lx->must_get_next (tk_brace_start);
+
+ // Mode must be set before dataheader is written here!
+ g_CurMode = MODE_MAINLOOP;
+ m_writer->write (dh_main_loop);
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_on_enter_exit()
+{
+ check_toplevel();
+ bool onenter = (token_is (tk_onenter));
+ m_lx->must_get_next (tk_brace_start);
+
+ // Mode must be set before dataheader is written here,
+ // because onenter goes to a separate buffer.
+ g_CurMode = onenter ? MODE_ONENTER : MODE_ONEXIT;
+ m_writer->write (onenter ? dh_on_enter : dh_on_exit);
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_variable_declaration()
+{
+ // For now, only globals are supported
+ if (g_CurMode != MODE_TOPLEVEL || g_CurState.is_empty() == false)
+ error ("variables must only be global for now");
+
+ type_e type = (token_is (tk_int)) ? TYPE_INT :
+ (token_is (tk_str)) ? TYPE_STRING :
+ TYPE_BOOL;
+
+ m_lx->must_get_next();
+ string varname = token_string();
+
+ // Var name must not be a number
+ if (varname.is_numeric())
+ error ("variable name must not be a number");
+
+ script_variable* var = declare_global_variable (type, varname);
+ (void) var;
+ m_lx->must_get_next (tk_semicolon);
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_goto()
+{
+ check_not_toplevel();
+
+ // Get the name of the label
+ m_lx->must_get_next();
+
+ // Find the mark this goto statement points to
+ string target = token_string();
+ int m = m_writer->find_byte_mark (target);
+
+ // If not set, define it
+ if (m == MAX_MARKS)
+ {
+ m = m_writer->add_mark (target);
+ g_undefined_labels[m] = new string (target);
+ }
+
+ // Add a reference to the mark.
+ m_writer->write (dh_goto);
+ m_writer->add_reference (m);
+ m_lx->must_get_next (tk_semicolon);
+ continue;
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_if()
+{
+ check_not_toplevel();
+ push_scope();
+
+ // Condition
+ m_lx->must_get_next (tk_paren_start);
+
+ // Read the expression and write it.
+ m_lx->must_get_next();
+ data_buffer* c = parse_expression (TYPE_INT);
+ m_writer->write_buffer (c);
+
+ m_lx->must_get_next (tk_paren_end);
+ m_lx->must_get_next (tk_brace_start);
+
+ // Add a mark - to here temporarily - and add a reference to it.
+ // Upon a closing brace, the mark will be adjusted.
+ int marknum = m_writer->add_mark ("");
+
+ // Use dh_if_not_goto - if the expression is not true, we goto the mark
+ // we just defined - and this mark will be at the end of the scope block.
+ m_writer->write (dh_if_not_goto);
+ m_writer->add_reference (marknum);
+
+ // Store it
+ SCOPE (0).mark1 = marknum;
+ SCOPE (0).type = e_if_scope;
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_else()
+{
+ check_not_toplevel();
+ m_lx->must_get_next (tk_brace_start);
+
+ // Don't use PushScope as it resets the scope
+ g_ScopeCursor++;
+
+ if (g_ScopeCursor >= MAX_SCOPE)
+ error ("too deep scope");
+
+ if (SCOPE (0).type != e_if_scope)
+ error ("else without preceding if");
+
+ // write down to jump to the end of the else statement
+ // Otherwise we have fall-throughs
+ SCOPE (0).mark2 = m_writer->add_mark ("");
+
+ // Instruction to jump to the end after if block is complete
+ m_writer->write (dh_goto);
+ m_writer->add_reference (SCOPE (0).mark2);
+
+ // Move the ifnot mark here and set type to else
+ m_writer->move_mark (SCOPE (0).mark1);
+ SCOPE (0).type = e_else_scope;
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_while_block()
+{
+ check_not_toplevel();
+ push_scope();
+
+ // While loops need two marks - one at the start of the loop and one at the
+ // end. The condition is checked at the very start of the loop, if it fails,
+ // we use goto to skip to the end of the loop. At the end, we loop back to
+ // the beginning with a go-to statement.
+ int mark1 = m_writer->add_mark (""); // start
+ int mark2 = m_writer->add_mark (""); // end
+
+ // Condition
+ m_lx->must_get_next (tk_paren_start);
+ m_lx->must_get_next();
+ data_buffer* expr = parse_expression (TYPE_INT);
+ m_lx->must_get_next (tk_paren_end);
+ m_lx->must_get_next (tk_brace_start);
+
+ // write condition
+ m_writer->write_buffer (expr);
+
+ // Instruction to go to the end if it fails
+ m_writer->write (dh_if_not_goto);
+ m_writer->add_reference (mark2);
+
+ // Store the needed stuff
+ SCOPE (0).mark1 = mark1;
+ SCOPE (0).mark2 = mark2;
+ SCOPE (0).type = e_while_scope;
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_for_block()
+{
+ check_not_toplevel();
+ push_scope();
+
+ // Initializer
+ m_lx->must_get_next (tk_paren_start);
+ m_lx->must_get_next();
+ data_buffer* init = parse_statement (w);
+
+ if (!init)
+ error ("bad statement for initializer of for");
+
+ m_lx->must_get_next (tk_semicolon);
+
+ // Condition
+ m_lx->must_get_next();
+ data_buffer* cond = parse_expression (TYPE_INT);
+
+ if (!cond)
+ error ("bad statement for condition of for");
+
+ m_lx->must_get_next (tk_semicolon);
+
+ // Incrementor
+ m_lx->must_get_next();
+ data_buffer* incr = parse_statement (w);
+
+ if (!incr)
+ error ("bad statement for incrementor of for");
+
+ m_lx->must_get_next (tk_paren_end);
+ m_lx->must_get_next (tk_brace_start);
+
+ // First, write out the initializer
+ m_writer->write_buffer (init);
+
+ // Init two marks
+ int mark1 = m_writer->add_mark ("");
+ int mark2 = m_writer->add_mark ("");
+
+ // Add the condition
+ m_writer->write_buffer (cond);
+ m_writer->write (dh_if_not_goto);
+ m_writer->add_reference (mark2);
+
+ // Store the marks and incrementor
+ SCOPE (0).mark1 = mark1;
+ SCOPE (0).mark2 = mark2;
+ SCOPE (0).buffer1 = incr;
+ SCOPE (0).type = e_for_scope;
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_do_block()
+{
+ check_not_toplevel();
+ push_scope();
+ m_lx->must_get_next (tk_brace_start);
+ SCOPE (0).mark1 = m_writer->add_mark ("");
+ SCOPE (0).type = e_do_scope;
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_switch_block()
+{
+ // This gets a bit tricky. switch is structured in the
+ // bytecode followingly:
+ //
+ // (expression)
+ // case a: goto casemark1
+ // case b: goto casemark2
+ // case c: goto casemark3
+ // goto mark1 // jump to end if no matches
+ // casemark1: ...
+ // casemark2: ...
+ // casemark3: ...
+ // mark1: // end mark
+
+ check_not_toplevel();
+ push_scope();
+ m_lx->must_get_next (tk_paren_start);
+ m_lx->must_get_next();
+ m_writer->write_buffer (parse_expression (TYPE_INT));
+ m_lx->must_get_next (tk_paren_end);
+ m_lx->must_get_next (tk_brace_start);
+ SCOPE (0).type = e_switch_scope;
+ SCOPE (0).mark1 = m_writer->add_mark (""); // end mark
+ SCOPE (0).buffer1 = null; // default header
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_switch_case()
+{
+ // case is only allowed inside switch
+ if (SCOPE (0).type != e_switch_scope)
+ error ("case label outside switch");
+
+ // Get the literal (Zandronum does not support expressions here)
+ m_lx->must_get_next (tk_number);
+ int num = m_lx->get_token()->text.to_long();
+ m_lx->must_get_next (tk_colon);
+
+ for (int i = 0; i < MAX_CASE; i++)
+ if (SCOPE (0).casenumbers[i] == num)
+ error ("multiple case %d labels in one switch", num);
+
+ // write down the expression and case-go-to. This builds
+ // the case tree. The closing event will write the actual
+ // blocks and move the marks appropriately.
+ // AddSwitchCase will add the reference to the mark
+ // for the case block that this heralds, and takes care
+ // of buffering setup and stuff like that.
+ // null the switch buffer for the case-go-to statement,
+ // we want it all under the switch, not into the case-buffers.
+ m_writer->SwitchBuffer = null;
+ m_writer->write (dh_case_goto);
+ m_writer->write (num);
+ add_switch_case (m_writer, null);
+ SCOPE (0).casenumbers[SCOPE (0).casecursor] = num;
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_switch_default()
+{
+ if (SCOPE (0).type != e_switch_scope)
+ error ("default label outside switch");
+
+ if (SCOPE (0).buffer1)
+ error ("multiple default labels in one switch");
+
+ m_lx->must_get_next (tk_colon);
+
+ // The default header is buffered into buffer1, since
+ // it has to be the last of the case headers
+ //
+ // Since the expression is pushed into the switch
+ // and is only popped when case succeeds, we have
+ // to pop it with dh_drop manually if we end up in
+ // a default.
+ data_buffer* b = new data_buffer;
+ SCOPE (0).buffer1 = b;
+ b->write (dh_drop);
+ b->write (dh_goto);
+ add_switch_case (m_writer, b);
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_break()
+{
+ if (!g_ScopeCursor)
+ error ("unexpected `break`");
+
+ m_writer->write (dh_goto);
+
+ // switch and if use mark1 for the closing point,
+ // for and while use mark2.
+ switch (SCOPE (0).type)
+ {
+ case e_if_scope:
+ case e_switch_scope:
+ {
+ m_writer->add_reference (SCOPE (0).mark1);
+ } break;
+
+ case e_for_scope:
+ case e_while_scope:
+ {
+ m_writer->add_reference (SCOPE (0).mark2);
+ } break;
+
+ default:
+ {
+ error ("unexpected `break`");
+ } break;
+ }
+
+ m_lx->must_get_next (tk_semicolon);
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_continue()
+{
+ m_lx->must_get_next (tk_semicolon);
+
+ int curs;
+ bool found = false;
+
+ // Fall through the scope until we find a loop block
+ for (curs = g_ScopeCursor; curs > 0 && !found; curs--)
+ {
+ switch (scopestack[curs].type)
+ {
+ case e_for_scope:
+ case e_while_scope:
+ case e_do_scope:
+ {
+ m_writer->write (dh_goto);
+ m_writer->add_reference (scopestack[curs].mark1);
+ found = true;
+ } break;
+
+ default:
+ break;
+ }
+ }
+
+ // No loop blocks
+ if (!found)
+ error ("`continue`-statement not inside a loop");
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_block_end()
+{
+ // Closing brace
+ // If we're in the block stack, we're descending down from it now
+ if (g_ScopeCursor > 0)
+ {
+ switch (SCOPE (0).type)
+ {
+ case e_if_scope:
+ // Adjust the closing mark.
+ m_writer->move_mark (SCOPE (0).mark1);
+
+ // We're returning from if, thus else can be next
+ g_CanElse = true;
+ break;
+
+ case e_else_scope:
+ // else instead uses mark1 for itself (so if expression
+ // fails, jump to else), mark2 means end of else
+ m_writer->move_mark (SCOPE (0).mark2);
+ break;
+
+ case e_for_scope:
+ // write the incrementor at the end of the loop block
+ m_writer->write_buffer (SCOPE (0).buffer1);
+
+ // fall-thru
+ case e_while_scope:
+ // write down the instruction to go back to the start of the loop
+ m_writer->write (dh_goto);
+ m_writer->add_reference (SCOPE (0).mark1);
+
+ // Move the closing mark here since we're at the end of the while loop
+ m_writer->move_mark (SCOPE (0).mark2);
+ break;
+
+ case e_do_scope:
+ {
+ m_lx->must_get_next (tk_while);
+ m_lx->must_get_next (tk_paren_start);
+ m_lx->must_get_next();
+ data_buffer* expr = parse_expression (TYPE_INT);
+ m_lx->must_get_next (tk_paren_end);
+ m_lx->must_get_next (tk_semicolon);
+
+ // If the condition runs true, go back to the start.
+ m_writer->write_buffer (expr);
+ m_writer->write (dh_if_goto);
+ m_writer->add_reference (SCOPE (0).mark1);
+ break;
+ }
+
+ case e_switch_scope:
+ {
+ // Switch closes. Move down to the record buffer of
+ // the lower block.
+ if (SCOPE (1).casecursor != -1)
+ m_writer->SwitchBuffer = SCOPE (1).casebuffers[SCOPE (1).casecursor];
+ else
+ m_writer->SwitchBuffer = null;
+
+ // If there was a default in the switch, write its header down now.
+ // If not, write instruction to jump to the end of switch after
+ // the headers (thus won't fall-through if no case matched)
+ if (SCOPE (0).buffer1)
+ m_writer->write_buffer (SCOPE (0).buffer1);
+ else
+ {
+ m_writer->write (dh_drop);
+ m_writer->write (dh_goto);
+ m_writer->add_reference (SCOPE (0).mark1);
+ }
+
+ // Go through all of the buffers we
+ // recorded down and write them.
+ for (int u = 0; u < MAX_CASE; u++)
+ {
+ if (!SCOPE (0).casebuffers[u])
+ continue;
+
+ m_writer->move_mark (SCOPE (0).casemarks[u]);
+ m_writer->write_buffer (SCOPE (0).casebuffers[u]);
+ }
+
+ // Move the closing mark here
+ m_writer->move_mark (SCOPE (0).mark1);
+ break;
+ }
+
+ case e_unknown_scope:
+ break;
+ }
+
+ // Descend down the stack
+ g_ScopeCursor--;
+ continue;
+ }
+
+ int dataheader = (g_CurMode == MODE_EVENT) ? dh_end_event :
+ (g_CurMode == MODE_MAINLOOP) ? dh_end_main_loop :
+ (g_CurMode == MODE_ONENTER) ? dh_end_on_enter :
+ (g_CurMode == MODE_ONEXIT) ? dh_end_on_exit : -1;
+
+ if (dataheader == -1)
+ error ("unexpected `}`");
+
+ // Data header must be written before mode is changed because
+ // onenter and mainloop go into special buffers, and we want
+ // the closing data headers into said buffers too.
+ m_writer->write (dataheader);
+ g_CurMode = MODE_TOPLEVEL;
+ m_lx->get_next (tk_semicolon);
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_const()
+{
+ constant_info info;
+
+ // Get the type
+ m_lx->must_get_next();
+ string typestring = token_string();
+ info.type = GetTypeByName (typestring);
+
+ if (info.type == TYPE_UNKNOWN || info.type == TYPE_VOID)
+ error ("unknown type `%1` for constant", typestring);
+
+ m_lx->must_get_next();
+ info.name = token_string();
+
+ m_lx->must_get_next (tk_assign);
+
+ switch (info.type)
+ {
+ case TYPE_BOOL:
+ case TYPE_INT:
+ {
+ m_lx->must_get_next (tk_number);
+ } break;
+
+ case TYPE_STRING:
+ {
+ m_lx->must_get_next (tk_string);
+ } break;
+
+ case TYPE_UNKNOWN:
+ case TYPE_VOID:
+ break;
+ }
+
+ info.val = m_lx->get_token()->text;
+ g_ConstInfo << info;
+
+ m_lx->must_get_next (tk_semicolon);
+}
+
+// ============================================================================
+//
+void botscript_parser::parse_label()
+{
+ check_not_toplevel();
+ string label_name = token_string();
+
+ // want no conflicts..
+ if (find_command_by_name (label_name))
+ error ("label name `%s` conflicts with command name\n", label_name);
+
+ if (find_global_variable (label_name))
+ error ("label name `%s` conflicts with variable\n", label_name);
+
+ // See if a mark already exists for this label
+ int mark = -1;
+
+ for (int i = 0; i < MAX_MARKS; i++)
+ {
+ if (g_undefined_labels[i] && *g_undefined_labels[i] == label_name)
+ {
+ mark = i;
+ m_writer->move_mark (i);
+
+ // No longer undefinde
+ delete g_undefined_labels[i];
+ g_undefined_labels[i] = null;
+ }
+ }
+
+ // Not found in unmarked lists, define it now
+ if (mark == -1)
+ m_writer->add_mark (label_name);
+
+ m_lx->must_get_next (tk_colon);
+}
+
+// ============================================================================
+// Parses a command call
+data_buffer* botscript_parser::ParseCommand (command_info* comm)
+{
+ data_buffer* r = new data_buffer (64);
+
+ if (g_CurMode == MODE_TOPLEVEL)
+ error ("command call at top level");
+
+ m_lx->must_get_next (tk_paren_start);
+ m_lx->must_get_next();
+
+ int curarg = 0;
+
+ while (1)
+ {
+ if (token_is (tk_paren_end))
+ {
+ if (curarg < comm->numargs)
+ error ("too few arguments passed to %s\n\tprototype: %s",
+ comm->name.chars(), get_command_signature (comm).chars());
+
+ break;
+ curarg++;
+ }
+
+ if (curarg >= comm->maxargs)
+ error ("too many arguments passed to %s\n\tprototype: %s",
+ comm->name.chars(), get_command_signature (comm).chars());
+
+ r->merge (parse_expression (comm->args[curarg].type));
+ m_lx->must_get_next();
+
+ if (curarg < comm->numargs - 1)
+ {
+ m_lx->must_be (tk_comma);
+ m_lx->must_get_next();
+ }
+ else if (curarg < comm->maxargs - 1)
+ {
+ // Can continue, but can terminate as well.
+ if (token_is (tk_paren_end))
+ {
+ curarg++;
+ break;
+ }
+ else
+ {
+ m_lx->must_be (tk_comma);
+ m_lx->must_get_next();
+ }
+ }
+
+ curarg++;
+ }
+
+ // If the script skipped any optional arguments, fill in defaults.
+ while (curarg < comm->maxargs)
+ {
+ r->write (dh_push_number);
+ r->write (comm->args[curarg].defvalue);
+ curarg++;
+ }
+
+ r->write (dh_command);
+ r->write (comm->number);
+ r->write (comm->maxargs);
+
+ return r;
+}
+
+// ============================================================================
+// Is the given operator an assignment operator?
+static bool is_assignment_operator (int oper)
+{
+ switch (oper)
+ {
+ case OPER_ASSIGNADD:
+ case OPER_ASSIGNSUB:
+ case OPER_ASSIGNMUL:
+ case OPER_ASSIGNDIV:
+ case OPER_ASSIGNMOD:
+ case OPER_ASSIGNLEFTSHIFT:
+ case OPER_ASSIGNRIGHTSHIFT:
+ case OPER_ASSIGN:
+ return true;
+ }
+
+ return false;
+}
+
+// ============================================================================
+// Finds an operator's corresponding dataheader
+static word get_data_header_by_operator (script_variable* var, int oper)
+{
+ if (is_assignment_operator (oper))
+ {
+ if (!var)
+ error ("operator %d requires left operand to be a variable\n", oper);
+
+ // TODO: At the moment, vars only are global
+ // OPER_ASSIGNLEFTSHIFT and OPER_ASSIGNRIGHTSHIFT do not
+ // have data headers, instead they are expanded out in
+ // the operator parser
+ switch (oper)
+ {
+ case OPER_ASSIGNADD: return dh_add_global_var;
+ case OPER_ASSIGNSUB: return dh_subtract_global_var;
+ case OPER_ASSIGNMUL: return dh_multiply_global_var;
+ case OPER_ASSIGNDIV: return dh_divide_global_var;
+ case OPER_ASSIGNMOD: return dh_mod_global_var;
+ case OPER_ASSIGN: return dh_assign_global_var;
+
+ default: error ("bad assignment operator!!\n");
+ }
+ }
+
+ switch (oper)
+ {
+ case OPER_ADD: return dh_add;
+ case OPER_SUBTRACT: return dh_subtract;
+ case OPER_MULTIPLY: return dh_multiply;
+ case OPER_DIVIDE: return dh_divide;
+ case OPER_MODULUS: return dh_modulus;
+ case OPER_EQUALS: return dh_equals;
+ case OPER_NOTEQUALS: return dh_not_equals;
+ case OPER_LESSTHAN: return dh_less_than;
+ case OPER_GREATERTHAN: return dh_greater_than;
+ case OPER_LESSTHANEQUALS: return dh_at_most;
+ case OPER_GREATERTHANEQUALS: return dh_at_least;
+ case OPER_LEFTSHIFT: return dh_left_shift;
+ case OPER_RIGHTSHIFT: return dh_right_shift;
+ case OPER_OR: return dh_or_logical;
+ case OPER_AND: return dh_and_logical;
+ case OPER_BITWISEOR: return dh_or_bitwise;
+ case OPER_BITWISEEOR: return dh_eor_bitwise;
+ case OPER_BITWISEAND: return dh_and_bitwise;
+ }
+
+ error ("DataHeaderByOperator: couldn't find dataheader for operator %d!\n", oper);
+ return 0;
+}
+
+// ============================================================================
+// Parses an expression, potentially recursively
+data_buffer* botscript_parser::parse_expression (type_e reqtype)
+{
+ data_buffer* retbuf = new data_buffer (64);
+
+ // Parse first operand
+ retbuf->merge (parse_expr_value (reqtype));
+
+ // Parse any and all operators we get
+ int oper;
+
+ while ( (oper = parse_operator (true)) != -1)
+ {
+ // We peeked the operator, move forward now
+ m_lx->skip();
+
+ // Can't be an assignement operator, those belong in assignments.
+ if (is_assignment_operator (oper))
+ error ("assignment operator inside expression");
+
+ // Parse the right operand.
+ m_lx->must_get_next();
+ data_buffer* rb = parse_expr_value (reqtype);
+
+ if (oper == OPER_TERNARY)
+ {
+ // Ternary operator requires - naturally - a third operand.
+ m_lx->must_get_next (tk_colon);
+ m_lx->must_get_next();
+ data_buffer* tb = parse_expr_value (reqtype);
+
+ // It also is handled differently: there isn't a dataheader for ternary
+ // operator. Instead, we abuse PUSHNUMBER and IFNOTGOTO for this.
+ // Behold, big block of writing madness! :P
+ int mark1 = retbuf->add_mark (""); // start of "else" case
+ int mark2 = retbuf->add_mark (""); // end of expression
+ retbuf->write (dh_if_not_goto); // if the first operand (condition)
+ retbuf->add_reference (mark1); // didn't eval true, jump into mark1
+ retbuf->merge (rb); // otherwise, perform second operand (true case)
+ retbuf->write (dh_goto); // afterwards, jump to the end, which is
+ retbuf->add_reference (mark2); // marked by mark2.
+ retbuf->move_mark (mark1); // move mark1 at the end of the true case
+ retbuf->merge (tb); // perform third operand (false case)
+ retbuf->move_mark (mark2); // move the ending mark2 here
+ }
+ else
+ {
+ // write to buffer
+ retbuf->merge (rb);
+ retbuf->write (get_data_header_by_operator (null, oper));
+ }
+ }
+
+ return retbuf;
+}
+
+// ============================================================================
+// Parses an operator string. Returns the operator number code.
+#define ISNEXT(C) (m_lx->peek_next_string (peek ? 1 : 0) == C)
+int botscript_parser::parse_operator (bool peek)
+{
+ string oper;
+
+ if (peek)
+ oper += m_lx->peek_next_string();
+ else
+ oper += token_string();
+
+ if (-oper == "strlen")
+ return OPER_STRLEN;
+
+ // Check one-char operators
+ bool equalsnext = ISNEXT ("=");
+
+ int o = (oper == "=" && !equalsnext) ? OPER_ASSIGN :
+ (oper == ">" && !equalsnext && !ISNEXT (">")) ? OPER_GREATERTHAN :
+ (oper == "<" && !equalsnext && !ISNEXT ("<")) ? OPER_LESSTHAN :
+ (oper == "&" && !ISNEXT ("&")) ? OPER_BITWISEAND :
+ (oper == "|" && !ISNEXT ("|")) ? OPER_BITWISEOR :
+ (oper == "+" && !equalsnext) ? OPER_ADD :
+ (oper == "-" && !equalsnext) ? OPER_SUBTRACT :
+ (oper == "*" && !equalsnext) ? OPER_MULTIPLY :
+ (oper == "/" && !equalsnext) ? OPER_DIVIDE :
+ (oper == "%" && !equalsnext) ? OPER_MODULUS :
+ (oper == "^") ? OPER_BITWISEEOR :
+ (oper == "?") ? OPER_TERNARY :
+ -1;
+
+ if (o != -1)
+ {
+ return o;
+ }
+
+ // Two-char operators
+ oper += m_lx->peek_next_string (peek ? 1 : 0);
+ equalsnext = m_lx->peek_next_string (peek ? 2 : 1) == ("=");
+
+ o = (oper == "+=") ? OPER_ASSIGNADD :
+ (oper == "-=") ? OPER_ASSIGNSUB :
+ (oper == "*=") ? OPER_ASSIGNMUL :
+ (oper == "/=") ? OPER_ASSIGNDIV :
+ (oper == "%=") ? OPER_ASSIGNMOD :
+ (oper == "==") ? OPER_EQUALS :
+ (oper == "!=") ? OPER_NOTEQUALS :
+ (oper == ">=") ? OPER_GREATERTHANEQUALS :
+ (oper == "<=") ? OPER_LESSTHANEQUALS :
+ (oper == "&&") ? OPER_AND :
+ (oper == "||") ? OPER_OR :
+ (oper == "<<" && !equalsnext) ? OPER_LEFTSHIFT :
+ (oper == ">>" && !equalsnext) ? OPER_RIGHTSHIFT :
+ -1;
+
+ if (o != -1)
+ {
+ m_lx->must_get_next();
+ return o;
+ }
+
+ // Three-char opers
+ oper += m_lx->peek_next_string (peek ? 2 : 1);
+ o = oper == "<<=" ? OPER_ASSIGNLEFTSHIFT :
+ oper == ">>=" ? OPER_ASSIGNRIGHTSHIFT :
+ -1;
+
+ if (o != -1)
+ {
+ m_lx->must_get_next();
+ m_lx->must_get_next();
+ }
+
+ return o;
+}
+
+// ============================================================================
+string botscript_parser::parse_float()
+{
+ m_lx->must_be (tk_number);
+ string floatstring = token_string();
+ lexer::token tok;
+
+ // Go after the decimal point
+ if (m_lx->peek_next (&tok) && tok.type == tk_dot)
+ {
+ m_lx->skip();
+ m_lx->must_get_next (tk_number);
+ floatstring += ".";
+ floatstring += token_string();
+ }
+
+ return floatstring;
+}
+
+// ============================================================================
+// Parses a value in the expression and returns the data needed to push
+// it, contained in a data buffer. A value can be either a variable, a command,
+// a literal or an expression.
+data_buffer* botscript_parser::parse_expr_value (type_e reqtype)
+{
+ data_buffer* b = new data_buffer (16);
+ script_variable* g;
+
+ // Prefixing "!" means negation.
+ bool negate = token_is (tk_exclamation_mark);
+
+ if (negate) // Jump past the "!"
+ m_lx->skip();
+
+ // Handle strlen
+ /* if (token_string() == "strlen")
+ {
+ m_lx->must_get_next (tk_paren_start);
+ m_lx->must_get_next();
+
+ // By this token we should get a string constant.
+ constant_info* constant = find_constant (token_string());
+
+ if (!constant || constant->type != TYPE_STRING)
+ error ("strlen only works with const str");
+
+ if (reqtype != TYPE_INT)
+ error ("strlen returns int but %s is expected\n", GetTypeName (reqtype).c_str());
+
+ b->write (dh_push_number);
+ b->write (constant->val.len());
+
+ m_lx->must_get_next (tk_paren_end);
+ }
+ else */
+ if (token_is (tk_paren_start))
+ {
+ // Expression
+ m_lx->must_get_next();
+ data_buffer* c = parse_expression (reqtype);
+ b->merge (c);
+ m_lx->must_get_next (tk_paren_end);
+ }
+ else if (command_info* comm = find_command_by_name (token_string()))
+ {
+ delete b;
+
+ // Command
+ if (reqtype && comm->returnvalue != reqtype)
+ error ("%s returns an incompatible data type", comm->name.chars());
+
+ b = ParseCommand (comm);
+ }
+ else if (constant_info* constant = find_constant (token_string()))
+ {
+ // Type check
+ if (reqtype != constant->type)
+ error ("constant `%s` is %s, expression requires %s\n",
+ constant->name.c_str(), GetTypeName (constant->type).c_str(),
+ GetTypeName (reqtype).c_str());
+
+ switch (constant->type)
+ {
+ case TYPE_BOOL:
+ case TYPE_INT:
+ b->write (dh_push_number);
+ b->write (atoi (constant->val));
+ break;
+
+ case TYPE_STRING:
+ b->write_string (constant->val);
+ break;
+
+ case TYPE_VOID:
+ case TYPE_UNKNOWN:
+ break;
+ }
+ }
+ else if ((g = find_global_variable (token_string())))
+ {
+ // Global variable
+ b->write (dh_push_global_var);
+ b->write (g->index);
+ }
+ else
+ {
+ // If nothing else, check for literal
+ switch (reqtype)
+ {
+ case TYPE_VOID:
+ case TYPE_UNKNOWN:
+ error ("unknown identifier `%1` (expected keyword, function or variable)", token_string());
+ break;
+
+ case TYPE_BOOL:
+ case TYPE_INT:
+ {
+ m_lx->must_be (tk_number);
+
+ // All values are written unsigned - thus we need to write the value's
+ // absolute value, followed by an unary minus for negatives.
+ b->write (dh_push_number);
+
+ long v = token_string().to_long();
+ b->write (static_cast<word> (abs (v)));
+
+ if (v < 0)
+ b->write (dh_unary_minus);
+
+ break;
+ }
+
+ case TYPE_STRING:
+ // PushToStringTable either returns the string index of the
+ // string if it finds it in the table, or writes it to the
+ // table and returns it index if it doesn't find it there.
+ m_lx->must_be (tk_string);
+ b->write_string (token_string());
+ break;
+ }
+ }
+
+ // Negate it now if desired
+ if (negate)
+ b->write (dh_negate_logical);
+
+ return b;
+}
+
+// ============================================================================
+// Parses an assignment. An assignment starts with a variable name, followed
+// by an assignment operator, followed by an expression value. Expects current
+// token to be the name of the variable, and expects the variable to be given.
+data_buffer* botscript_parser::ParseAssignment (script_variable* var)
+{
+ bool global = !var->statename.len();
+
+ // Get an operator
+ m_lx->must_get_next();
+ int oper = parse_operator();
+
+ if (!is_assignment_operator (oper))
+ error ("expected assignment operator");
+
+ if (g_CurMode == MODE_TOPLEVEL)
+ error ("can't alter variables at top level");
+
+ // Parse the right operand
+ m_lx->must_get_next();
+ data_buffer* retbuf = new data_buffer;
+ data_buffer* expr = parse_expression (var->type);
+
+ // <<= and >>= do not have data headers. Solution: expand them.
+ // a <<= b -> a = a << b
+ // a >>= b -> a = a >> b
+ if (oper == OPER_ASSIGNLEFTSHIFT || oper == OPER_ASSIGNRIGHTSHIFT)
+ {
+ retbuf->write (global ? dh_push_global_var : dh_push_local_var);
+ retbuf->write (var->index);
+ retbuf->merge (expr);
+ retbuf->write ((oper == OPER_ASSIGNLEFTSHIFT) ? dh_left_shift : dh_right_shift);
+ retbuf->write (global ? dh_assign_global_var : dh_assign_local_var);
+ retbuf->write (var->index);
+ }
+ else
+ {
+ retbuf->merge (expr);
+ long dh = get_data_header_by_operator (var, oper);
+ retbuf->write (dh);
+ retbuf->write (var->index);
+ }
+
+ return retbuf;
+}
+
+void botscript_parser::push_scope()
+{
+ g_ScopeCursor++;
+
+ if (g_ScopeCursor >= MAX_SCOPE)
+ error ("too deep scope");
+
+ ScopeInfo* info = &SCOPE (0);
+ info->type = e_unknown_scope;
+ info->mark1 = 0;
+ info->mark2 = 0;
+ info->buffer1 = null;
+ info->casecursor = -1;
+
+ for (int i = 0; i < MAX_CASE; i++)
+ {
+ info->casemarks[i] = MAX_MARKS;
+ info->casebuffers[i] = null;
+ info->casenumbers[i] = -1;
+ }
+}
+
+data_buffer* botscript_parser::parse_statement (object_writer* w)
+{
+ if (find_constant (token_string())) // There should not be constants here.
+ error ("invalid use for constant\n");
+
+ // If it's a variable, expect assignment.
+ if (script_variable* var = find_global_variable (token_string()))
+ return ParseAssignment (var);
+
+ return null;
+}
+
+void botscript_parser::add_switch_case (object_writer* w, data_buffer* b)
+{
+ ScopeInfo* info = &SCOPE (0);
+
+ info->casecursor++;
+
+ if (info->casecursor >= MAX_CASE)
+ error ("too many cases in one switch");
+
+ // Init a mark for the case buffer
+ int m = m_writer->add_mark ("");
+ info->casemarks[info->casecursor] = m;
+
+ // Add a reference to the mark. "case" and "default" both
+ // add the necessary bytecode before the reference.
+ if (b)
+ b->add_reference (m);
+ else
+ m_writer->add_reference (m);
+
+ // Init a buffer for the case block and tell the object
+ // writer to record all written data to it.
+ info->casebuffers[info->casecursor] = m_writer->SwitchBuffer = new data_buffer;
+}
+
+// ============================================================================
+//
+constant_info* find_constant (const string& tok)
+{
+ for (int i = 0; i < g_ConstInfo.size(); i++)
+ if (g_ConstInfo[i].name == tok)
+ return &g_ConstInfo[i];
+
+ return null;
+}
+
+// ============================================================================
+//
+bool botscript_parser::token_is (e_token a)
+{
+ return (m_lx->get_token_type() == a);
+}
+
+// ============================================================================
+//
+string botscript_parser::token_string()
+{
+ return m_lx->get_token()->text;
+}
+
+// ============================================================================
+//
+string botscript_parser::describe_position() const
+{
+ lexer::token* tok = m_lx->get_token();
+ return tok->file + ":" + string (tok->line) + ":" + string (tok->column);
+}