--- a/src/parser.cxx Mon Jan 13 00:15:38 2014 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,1381 +0,0 @@
-/*
- Copyright (c) 2013-2014, 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 TOKEN (string (m_lx->get_token()->string))
-#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;
-string* g_UndefinedLabels[MAX_MARKS];
-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.chars());
-}
-
-// ============================================================================
-//
-void botscript_parser::check_not_toplevel()
-{
- if (g_CurMode == MODE_TOPLEVEL)
- error ("%1-statements must not be defined at top level!", TOKEN.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)
-{
- // Lex and preprocess the file
- m_lx->process_file (file_name);
-
- // Zero the entire block stack first
- for (int i = 0; i < MAX_SCOPE; i++)
- ZERO (scopestack[i]);
-
- for (int i = 0; i < MAX_MARKS; i++)
- g_UndefinedLabels[i] = null;
-
- while (m_lx->get_next())
- {
- // Check if else is potentically valid
- if (TOKEN == "else" && !g_CanElse)
- error ("else without preceding if");
-
- if (TOKEN != "else")
- g_CanElse = false;
-
- switch (m_lx->get_token())
- {
- case tk_state:
- {
- check_toplevel();
- m_lx->must_get_next (tk_string);
-
- // State name must be a word.
- if (TOKEN.first (" ") != -1)
- error ("state name must be a single word, got `%1`", TOKEN);
-
- string statename = TOKEN;
-
- // stateSpawn is special - it *must* be defined. If we
- // encountered it, then mark down that we have it.
- if (-TOKEN == "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)
- w->write_member_buffers();
-
- w->write (dh_state_name);
- w->write_string (statename);
- w->write (dh_state_index);
- w->write (g_NumStates);
-
- g_NumStates++;
- g_CurState = TOKEN;
- g_GotMainLoop = false;
- }
- break;
-
- // ============================================================
- //
- case tk_event:
- {
- check_toplevel();
-
- // Event definition
- 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;
- w->write (dh_event);
- w->write (e->number);
- g_NumEvents++;
- continue;
- } break;
-
- // ============================================================
- //
- case tk_mainloop:
- {
- check_toplevel();
- m_lx->must_get_next (tk_brace_start);
-
- // Mode must be set before dataheader is written here!
- g_CurMode = MODE_MAINLOOP;
- w->write (dh_main_loop);
- }
- break;
-
- // ============================================================
- //
- case tk_onenter:
- case tk_onexit:
- {
- check_toplevel();
- bool onenter = (m_lx->get_token() == "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;
- w->write (onenter ? dh_on_enter : dh_on_exit);
- }
- break;
-
- // ============================================================
- //
- case tk_int:
- case tk_str:
- case tk_void:
- {
- // For now, only globals are supported
- if (g_CurMode != MODE_TOPLEVEL || g_CurState.len())
- 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();
-
- // Var name must not be a number
- if (TOKEN.is_numeric())
- error ("variable name must not be a number");
-
- string varname = TOKEN;
- script_variable* var = declare_global_variable (this, type, varname);
- m_lx->must_get_next (tk_semicolon);
- }
- break;
-
- // ============================================================
- //
- case tk_goto:
- {
- check_not_toplevel();
-
- // Get the name of the label
- m_lx->must_get_next();
-
- // Find the mark this goto statement points to
- int m = w->find_byte_mark (TOKEN);
-
- // If not set, define it
- if (m == MAX_MARKS)
- {
- m = w->add_mark (TOKEN);
- g_UndefinedLabels[m] = new string (TOKEN);
- }
-
- // Add a reference to the mark.
- w->write (dh_goto);
- w->add_reference (m);
- m_lx->must_get_next (tk_semicolon);
- continue;
- }
-
- // ============================================================
- //
- case tk_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);
- w->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 = w->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.
- w->write (dh_if_not_goto);
- w->add_reference (marknum);
-
- // Store it
- SCOPE (0).mark1 = marknum;
- SCOPE (0).type = e_if_scope;
- } break;
-
- // ============================================================
- //
- case tk_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 = w->add_mark ("");
-
- // Instruction to jump to the end after if block is complete
- w->write (dh_goto);
- w->add_reference (SCOPE (0).mark2);
-
- // Move the ifnot mark here and set type to else
- w->move_mark (SCOPE (0).mark1);
- SCOPE (0).type = e_else_scope;
- }
- break;
-
- // ============================================================
- //
- case tk_while:
- {
- 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 = w->add_mark (""); // start
- int mark2 = w->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
- w->write_buffer (expr);
-
- // Instruction to go to the end if it fails
- w->write (dh_if_not_goto);
- w->add_reference (mark2);
-
- // Store the needed stuff
- SCOPE (0).mark1 = mark1;
- SCOPE (0).mark2 = mark2;
- SCOPE (0).type = e_while_scope;
- }
- break;
-
- // ============================================================
- //
- case tk_for:
- {
- 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
- w->write_buffer (init);
-
- // Init two marks
- int mark1 = w->add_mark ("");
- int mark2 = w->add_mark ("");
-
- // Add the condition
- w->write_buffer (cond);
- w->write (dh_if_not_goto);
- w->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;
- }
- break;
-
- // ============================================================
- //
- case tk_do:
- {
- check_not_toplevel();
- push_scope();
- m_lx->must_get_next (tk_brace_start);
- SCOPE (0).mark1 = w->add_mark ("");
- SCOPE (0).type = e_do_scope;
- }
- break;
-
- // ============================================================
- //
- case tk_switch:
- {
- // 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();
- w->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 = w->add_mark (""); // end mark
- SCOPE (0).buffer1 = null; // default header
- }
- break;
-
- // ============================================================
- //
- case tk_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.
- w->SwitchBuffer = null;
- w->write (dh_case_goto);
- w->write (num);
- add_switch_case (w, null);
- SCOPE (0).casenumbers[SCOPE (0).casecursor] = num;
- }
- break;
-
- // ============================================================
- //
- case tk_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 (w, b);
- }
- break;
-
- // ============================================================
- //
- case tk_break:
- {
- if (!g_ScopeCursor)
- error ("unexpected `break`");
-
- w->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:
- {
- w->add_reference (SCOPE (0).mark1);
- } break;
-
- case e_for_scope:
- case e_while_scope:
- {
- w->add_reference (SCOPE (0).mark2);
- } break;
-
- default:
- {
- error ("unexpected `break`");
- } break;
- }
-
- m_lx->must_get_next (tk_semicolon);
- }
- break;
-
- // ============================================================
- //
- case tk_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:
- {
- w->write (dh_goto);
- w->add_reference (scopestack[curs].mark1);
- found = true;
- } break;
-
- default:
- break;
- }
- }
-
- // No loop blocks
- if (!found)
- error ("`continue`-statement not inside a loop");
- }
- break;
-
- case tk_brace_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.
- w->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
- w->move_mark (SCOPE (0).mark2);
- break;
-
- case e_for_scope:
- // write the incrementor at the end of the loop block
- w->write_buffer (SCOPE (0).buffer1);
-
- // fall-thru
- case e_while_scope:
- // write down the instruction to go back to the start of the loop
- w->write (dh_goto);
- w->add_reference (SCOPE (0).mark1);
-
- // Move the closing mark here since we're at the end of the while loop
- w->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.
- w->write_buffer (expr);
- w->write (dh_if_goto);
- w->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)
- w->SwitchBuffer = SCOPE (1).casebuffers[SCOPE (1).casecursor];
- else
- w->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)
- w->write_buffer (SCOPE (0).buffer1);
- else
- {
- w->write (dh_drop);
- w->write (dh_goto);
- w->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;
-
- w->move_mark (SCOPE (0).casemarks[u]);
- w->write_buffer (SCOPE (0).casebuffers[u]);
- }
-
- // Move the closing mark here
- w->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.
- w->write (dataheader);
- g_CurMode = MODE_TOPLEVEL;
- lexer::token* tok;
- m_lx->get_next (tk_semicolon);
- }
- break;
-
- // ============================================================
- case tk_const:
- {
- constant_info info;
-
- // Get the type
- m_lx->must_get_next();
- info.type = GetTypeByName (TOKEN);
-
- if (info.type == TYPE_UNKNOWN || info.type == TYPE_VOID)
- error ("unknown type `%s` for constant", TOKEN.c_str());
-
- m_lx->must_get_next();
- info.name = TOKEN;
-
- m_lx->must_get_next (tk_assign);
-
- switch (info.type)
- {
- case TYPE_BOOL:
- case TYPE_INT:
- {
- m_lx->must_get_next (tk_number);
- info.val = m_lx->get_token()->text.to_long();
- } break;
-
- case TYPE_STRING:
- {
- m_lx->must_get_next (tk_string);
- info.val = m_lx->get_token()->text;
- } break;
-
- case TYPE_UNKNOWN:
- case TYPE_VOID:
- break;
- }
-
- g_ConstInfo << info;
-
- m_lx->must_get_next (tk_semicolon);
- continue;
- }
-
- default:
- {
- // ============================================================
- // Label
- lexer::token* next;
- if (m_lx->get_token() == tk_symbol &&
- m_lx->peek_next (next) &&
- next->type == tk_colon)
- {
- check_not_toplevel();
- string label_name = token_string();
-
- // want no conflicts..
- if (FindCommand (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_UndefinedLabels[i] && *g_UndefinedLabels[i] == label_name)
- {
- mark = i;
- w->move_mark (i);
-
- // No longer undefinde
- delete g_UndefinedLabels[i];
- g_UndefinedLabels[i] = null;
- }
- }
-
- // Not found in unmarked lists, define it now
- if (mark == -1)
- w->add_mark (label_name);
-
- m_lx->must_get_next (tk_colon);
- continue;
- }
-
- // Check if it's a command
- CommandDef* comm = FindCommand (TOKEN);
-
- if (comm)
- {
- w->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 `%s`", TOKEN.chars());
-
- w->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_UndefinedLabels[i])
- error ("label `%s` is referenced via `goto` but isn't defined\n", g_UndefinedLabels[i]->chars());
-
- // Dump the last state's onenter and mainloop
- w->write_member_buffers();
-
- // String table
- w->write_string_table();
-}
-
-// ============================================================================
-// Parses a command call
-data_buffer* botscript_parser::ParseCommand (CommandDef* 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 (m_lx->get_token() == tk_paren_end)
- {
- if (curarg < comm->numargs)
- error ("too few arguments passed to %s\n\tprototype: %s",
- comm->name.chars(), GetCommandPrototype (comm).chars());
-
- break;
- curarg++;
- }
-
- if (curarg >= comm->maxargs)
- error ("too many arguments passed to %s\n\tprototype: %s",
- comm->name.chars(), GetCommandPrototype (comm).chars());
-
- r->merge (parse_expression (comm->argtypes[curarg]));
- 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 (m_lx->get_token() == 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->defvals[curarg]);
- 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) (PeekNext (peek ? 1 : 0) == C)
-int botscript_parser::parse_operator (bool peek)
-{
- string oper;
-
- if (peek)
- oper += m_lx->peek_next_string();
- else
- oper += TOKEN;
-
- 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;
- 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 = (m_lx->get_token() == tk_exclamation_mark);
-
- if (negate) // Jump past the "!"
- m_lx->skip();
-
- // Handle strlen
- if (TOKEN == "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);
-
- 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 == "(")
- {
- // 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 (CommandDef* comm = FindCommand (TOKEN))
- {
- 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))
- {
- // 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)))
- {
- // 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 `%s` (expected keyword, function or variable)", TOKEN.chars());
- 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 = atol (TOKEN);
- 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);
- 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)) // 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))
- 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 = w->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
- w->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] = w->SwitchBuffer = new data_buffer;
-}
-
-constant_info* find_constant (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() == 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);
-}
\ No newline at end of file