src/scriptvm/common.h

/*
 * Copyright (c) 2014 Christian Schoenebeck
 *
 * http://www.linuxsampler.org
 *
 * This file is part of LinuxSampler and released under the same terms.
 * See README file for details.
 */

// This header defines data types shared between the VM core implementation
// (inside the current source directory) and other parts of the sampler
// (located at other source directories).

#ifndef LS_INSTR_SCRIPT_PARSER_COMMON_H
#define LS_INSTR_SCRIPT_PARSER_COMMON_H

#include "../common/global.h"
#include <vector>
#include <map>
#include <stddef.h> // offsetof()

namespace LinuxSampler {
    
    enum ParserIssueType_t {
        PARSER_ERROR,
        PARSER_WARNING
    };

    enum ExprType_t {
        EMPTY_EXPR, ///< i.e. on invalid expressions or i.e. a function call that does not return a result value
        INT_EXPR,
        INT_ARR_EXPR,
        STRING_EXPR,
        STRING_ARR_EXPR,
    };

    enum StmtFlags_t {
       STMT_SUCCESS = 0, ///< Function / statement was executed successfully, no error occurred.
       STMT_ABORT_SIGNALLED = 1, ///< VM should stop the current callback execution (usually because of an error, but might also be without an error reason).
       STMT_SUSPEND_SIGNALLED = (1<<1),
       STMT_ERROR_OCCURRED = (1<<2),
    };

    enum VMExecStatus_t {
        VM_EXEC_NOT_RUNNING = 0,
        VM_EXEC_RUNNING = 1,
        VM_EXEC_SUSPENDED = (1<<1),
        VM_EXEC_ERROR = (1<<2),
    };

    class VMIntExpr;
    class VMStringExpr;

    class VMExpr {
    public:
        virtual ExprType_t exprType() const = 0;
        VMIntExpr* asInt() const;
        VMStringExpr* asString() const;
    };

    class VMIntExpr : virtual public VMExpr {
    public:
        virtual int evalInt() = 0;
        ExprType_t exprType() const { return INT_EXPR; }
    };

    class VMStringExpr : virtual public VMExpr {
    public:
        virtual String evalStr() = 0;
        ExprType_t exprType() const { return STRING_EXPR; }
    };

    class VMFnArgs {
    public:
        virtual int argsCount() const = 0;
        virtual VMExpr* arg(int i) = 0;
    };

    class VMFnResult {
    public:
        virtual VMExpr* resultValue() = 0;
        virtual StmtFlags_t resultFlags() { return STMT_SUCCESS; }
    };

    /** @brief VM built-in function.
     *
     * Abstract base class for built-in script functions, defining the interface
     * for all built-in script function implementations.
     */
    class VMFunction {
    public:
        /**
         * Script data type of the function's return value. If the function does
         * not return any value, then it returns EMPTY_EXPR here.
         */
        virtual ExprType_t returnType() = 0;

        /**
         * Minimum amount of function arguments this function accepts. If a
         * script is calling this function with less arguments, the script
         * parser will throw a parser error.
         */
        virtual int minRequiredArgs() const = 0;

        /**
         * Maximum amount of function arguments this functions accepts. If a
         * script is calling this function with more arguments, the script
         * parser will throw a parser error.
         */
        virtual int maxAllowedArgs() const = 0;

        /**
         * Script data type of the function's @c iArg 'th function argument.
         * The information provided here is less strong than acceptsArgType().
         * The parser will compare argument data types provided in scripts by
         * calling cceptsArgType(). The return value of argType() is used by the
         * parser instead to show an appropriate parser error which data type
         * this function usually expects as "default" data type. Reason: a
         * function may accept multiple data types for a certain function
         * argument and would automatically cast the passed argument value in
         * that case to the type it actually needs.
         *
         * @param iArg - index of the function argument in question
         */
        virtual ExprType_t argType(int iArg) const = 0;

        /**
         * This function is called by the parser to check whether arguments
         * passed in scripts to this function are accepted by this function. If
         * a script calls this function with an argument's data type not
         * accepted by this function, the parser will throw a parser error.
         *
         * @param iArg - index of the function argument in question
         * @param type - script data type used for this function argument by
         *               currently parsed script
         */
        virtual bool acceptsArgType(int iArg, ExprType_t type) const = 0;

        /**
         * Implements the actual function execution. This function is called by
         * the VM when this function shall be executed at script runtime.
         *
         * @param args - function arguments for executing this built-in function
         */
        virtual VMFnResult* exec(VMFnArgs* args) = 0;

        /**
         * Concenience method for function implementations to show warning
         * messages.
         *
         * @param txt - warning text
         */
        void wrnMsg(const String& txt);

        /**
         * Concenience method for function implementations to show error
         * messages.
         *
         * @param txt - error text
         */
        void errMsg(const String& txt);
    };

    /**
     * POD base of VMIntRelPtr and VMInt8RelPtr structures. Not intended to be
     * used directly. Use VMIntRelPtr or VMInt8RelPtr instead.
     */
    struct VMRelPtr {
        void** base; ///< Base pointer.
        int offset;  ///< Offset (in bytes) to base pointer.
    };

    /** @brief Pointer to built-in VM integer variable (of C/C++ type int).
     *
     * Used for defining built-in integer script variables.
     *
     * @b CAUTION: You may only use this class for pointing to C/C++ variables
     * of type "int" (which on most systems is 32 bit in size). If the C/C++ int
     * variable you want to reference is only 8 bit in size, then you @b must
     * use VMInt8RelPtr instead!
     *
     * For efficiency reasons the actual native C/C++ int variable is referenced
     * by two components here. The actual native int C/C++ variable in memory
     * is dereferenced at VM run-time by taking the @c base pointer dereference
     * and adding @c offset bytes. This has the advantage that for a large
     * number of built-in int variables, only one (or few) base pointer need
     * to be re-assigned before running a script, instead of updating each
     * built-in variable each time before a script is executed.
     *
     * Refer to DECLARE_VMINT() for example code.
     *
     * @see VMInt8RelPtr, DECLARE_VMINT()
     */
    struct VMIntRelPtr : VMRelPtr {
        VMIntRelPtr() {
            base   = NULL;
            offset = 0;
        }
        VMIntRelPtr(const VMRelPtr& data) {
            base   = data.base;
            offset = data.offset;
        }
        virtual int evalInt() { return *(int*)&(*(uint8_t**)base)[offset]; }
        virtual void assign(int i) { *(int*)&(*(uint8_t**)base)[offset] = i; }
    };

    /** @brief Pointer to built-in VM integer variable (of C/C++ type int8_t).
     *
     * Used for defining built-in integer script variables.
     *
     * @b CAUTION: You may only use this class for pointing to C/C++ variables
     * of type "int8_t" (8 bit integer). If the C/C++ int variable you want to
     * reference is an "int" type (which is 32 bit on most systems), then you
     * @b must use VMIntRelPtr instead!
     *
     * For efficiency reasons the actual native C/C++ int variable is referenced
     * by two components here. The actual native int C/C++ variable in memory
     * is dereferenced at VM run-time by taking the @c base pointer dereference
     * and adding @c offset bytes. This has the advantage that for a large
     * number of built-in int variables, only one (or few) base pointer need
     * to be re-assigned before running a script, instead of updating each
     * built-in variable each time before a script is executed.
     *
     * Refer to DECLARE_VMINT() for example code.
     *
     * @see VMIntRelPtr, DECLARE_VMINT()
     */
    struct VMInt8RelPtr : VMIntRelPtr {
        VMInt8RelPtr() : VMIntRelPtr() {}
        VMInt8RelPtr(const VMRelPtr& data) : VMIntRelPtr(data) {}
        virtual int evalInt() OVERRIDE {
            return *(uint8_t*)&(*(uint8_t**)base)[offset];
        }
        virtual void assign(int i) OVERRIDE {
            *(uint8_t*)&(*(uint8_t**)base)[offset] = i;
        }
    };

    /**
     * Convenience macro for initializing VMIntRelPtr and VMInt8RelPtr
     * structures. Example:
     * @code
     * struct Foo {
     *   uint8_t a;
     *   int b;
     * };
     *
     * Foo foo1 = (Foo) { 1, 3000 };
     * Foo foo2 = (Foo) { 2, 4000 };
     *
     * Foo* pFoo;
     *
     * VMInt8RelPtr var1 = DECLARE_VMINT(pFoo, class Foo, a);
     * VMIntRelPtr  var2 = DECLARE_VMINT(pFoo, class Foo, b);
     *
     * pFoo = &foo1;
     * printf("%d\n", var1->evalInt()); // will print 1
     * printf("%d\n", var2->evalInt()); // will print 3000
     *
     * pFoo = &foo2;
     * printf("%d\n", var1->evalInt()); // will print 2
     * printf("%d\n", var2->evalInt()); // will print 4000
     * @endcode
     */
    #define DECLARE_VMINT(basePtr, T_struct, T_member) ( \
        (VMRelPtr) {                                     \
            (void**) &basePtr,                           \
            offsetof(T_struct, T_member)                 \
        }                                                \
    )                                                    \

    /** @brief Built-in VM 8 bit integer array variable.
     *
     * Used for defining built-in integer array script variables.
     */
    struct VMInt8Array {
        int8_t* data;
        int size;

        VMInt8Array() : data(NULL), size(0) {}
    };

    /** @brief Provider for built-in script functions and variables.
     *
     * Abstract base class defining the interface for all classes which add and
     * implement built-in script functions and built-in script variables.
     */
    class VMFunctionProvider {
    public:
        /**
         * Returns pointer to the built-in function with the given function
         * name, or NULL if there is no built-in function with that name.
         *
         * @param name - function name
         */
        virtual VMFunction* functionByName(const String& name) = 0;

        /**
         * Returns a variable name indexed map of all built-in script variables
         * which point to native "int" (usually 32 bit) variables.
         */
        virtual std::map<String,VMIntRelPtr*> builtInIntVariables() = 0;

        /**
         * Returns a variable name indexed map of all built-in script variables
         * which point to native "int8_t" (8 bit) variables.
         */
        virtual std::map<String,VMInt8Array*> builtInIntArrayVariables() = 0;

        /**
         * Returns a variable name indexed map of all built-in constant script
         * variables, which never change their value at runtime.
         */
        virtual std::map<String,int> builtInConstIntVariables() = 0;
    };

    /** @brief Execution state of a virtual machine.
     *
     * An instance of this abstract base class represents exactly one execution
     * state of a virtual machine. This encompasses most notably the VM
     * execution stack, and VM polyphonic variables. It does not contain global
     * variable. Global variables are contained in the VMParserContext object.
     * You might see a VMExecContext object as one virtual thread of the virtual
     * machine.
     *
     * In contrast to a VMParserContext, a VMExecContext is not tied to a
     * ScriptVM instance. Thus you can use a VMExecContext with different
     * ScriptVM instances, however not concurrently at the same time.
     *
     * @see VMParserContext
     */
    class VMExecContext {
    public:
        virtual ~VMExecContext() {}
        virtual int suspensionTimeMicroseconds() const = 0;
    };

    class VMEventHandler {
    public:
        virtual String eventHandlerName() const = 0;
    };

    struct ParserIssue {
        String txt;
        int line;
        ParserIssueType_t type;

        inline void dump() {
            switch (type) {
                case PARSER_ERROR:
                    printf("[ERROR] line %d: %s\n", line, txt.c_str());
                    break;
                case PARSER_WARNING:
                    printf("[Warning] line %d: %s\n", line, txt.c_str());
                    break;
            }
        }
        
        inline bool isErr() const { return type == PARSER_ERROR;   }
        inline bool isWrn() const { return type == PARSER_WARNING; }
    };

    inline String typeStr(const ExprType_t& type) {
        switch (type) {
            case EMPTY_EXPR: return "empty";
            case INT_EXPR: return "integer";
            case INT_ARR_EXPR: return "integer array";
            case STRING_EXPR: return "string";
            case STRING_ARR_EXPR: return "string array";
        }
        return "invalid";
    }

    /** @brief Virtual machine representation of a script.
     *
     * An instance of this abstract base class represents a parsed script,
     * translated into a virtual machine. You should first check if there were
     * any parser errors. If there were any parser errors, you should refrain
     * from executing the virtual machine. Otherwise if there were no parser
     * errors (i.e. only warnings), then you might access one of the script's
     * event handlers by i.e. calling eventHandlerByName() and pass the
     * respective event handler to the ScriptVM class (or to one of its
     * descendants) for execution.
     *
     * @see VMExecContext
     */
    class VMParserContext {
    public:
        virtual ~VMParserContext() {}
        virtual std::vector<ParserIssue> issues() const = 0;
        virtual std::vector<ParserIssue> errors() const = 0;
        virtual std::vector<ParserIssue> warnings() const = 0;
        virtual VMEventHandler* eventHandler(uint index) = 0;
        virtual VMEventHandler* eventHandlerByName(const String& name) = 0;
    };

} // namespace LinuxSampler

#endif // LS_INSTR_SCRIPT_PARSER_COMMON_H
1	schoenebeck	2581	/*
2			* Copyright (c) 2014 Christian Schoenebeck
3			*
4			* http://www.linuxsampler.org
5			*
6			* This file is part of LinuxSampler and released under the same terms.
7			* See README file for details.
8			*/
9
10			// This header defines data types shared between the VM core implementation
11			// (inside the current source directory) and other parts of the sampler
12			// (located at other source directories).
13
14			#ifndef LS_INSTR_SCRIPT_PARSER_COMMON_H
15			#define LS_INSTR_SCRIPT_PARSER_COMMON_H
16
17			#include "../common/global.h"
18	schoenebeck	2588	#include <vector>
19	schoenebeck	2594	#include <map>
20			#include <stddef.h> // offsetof()
21	schoenebeck	2581
22			namespace LinuxSampler {
23
24			enum ParserIssueType_t {
25			PARSER_ERROR,
26			PARSER_WARNING
27			};
28
29			enum ExprType_t {
30			EMPTY_EXPR, ///< i.e. on invalid expressions or i.e. a function call that does not return a result value
31			INT_EXPR,
32			INT_ARR_EXPR,
33			STRING_EXPR,
34			STRING_ARR_EXPR,
35			};
36
37			enum StmtFlags_t {
38			STMT_SUCCESS = 0, ///< Function / statement was executed successfully, no error occurred.
39			STMT_ABORT_SIGNALLED = 1, ///< VM should stop the current callback execution (usually because of an error, but might also be without an error reason).
40			STMT_SUSPEND_SIGNALLED = (1<<1),
41			STMT_ERROR_OCCURRED = (1<<2),
42			};
43
44			enum VMExecStatus_t {
45			VM_EXEC_NOT_RUNNING = 0,
46			VM_EXEC_RUNNING = 1,
47			VM_EXEC_SUSPENDED = (1<<1),
48			VM_EXEC_ERROR = (1<<2),
49			};
50
51	schoenebeck	2596	class VMIntExpr;
52			class VMStringExpr;
53
54	schoenebeck	2581	class VMExpr {
55			public:
56			virtual ExprType_t exprType() const = 0;
57	schoenebeck	2596	VMIntExpr* asInt() const;
58			VMStringExpr* asString() const;
59	schoenebeck	2581	};
60
61			class VMIntExpr : virtual public VMExpr {
62			public:
63			virtual int evalInt() = 0;
64			ExprType_t exprType() const { return INT_EXPR; }
65			};
66
67			class VMStringExpr : virtual public VMExpr {
68			public:
69			virtual String evalStr() = 0;
70			ExprType_t exprType() const { return STRING_EXPR; }
71			};
72
73			class VMFnArgs {
74			public:
75			virtual int argsCount() const = 0;
76			virtual VMExpr* arg(int i) = 0;
77			};
78
79			class VMFnResult {
80			public:
81			virtual VMExpr* resultValue() = 0;
82			virtual StmtFlags_t resultFlags() { return STMT_SUCCESS; }
83			};
84
85	schoenebeck	2612	/** @brief VM built-in function.
86			*
87			* Abstract base class for built-in script functions, defining the interface
88			* for all built-in script function implementations.
89			*/
90	schoenebeck	2581	class VMFunction {
91			public:
92	schoenebeck	2612	/**
93			* Script data type of the function's return value. If the function does
94			* not return any value, then it returns EMPTY_EXPR here.
95			*/
96	schoenebeck	2581	virtual ExprType_t returnType() = 0;
97	schoenebeck	2612
98			/**
99			* Minimum amount of function arguments this function accepts. If a
100			* script is calling this function with less arguments, the script
101			* parser will throw a parser error.
102			*/
103	schoenebeck	2581	virtual int minRequiredArgs() const = 0;
104	schoenebeck	2612
105			/**
106			* Maximum amount of function arguments this functions accepts. If a
107			* script is calling this function with more arguments, the script
108			* parser will throw a parser error.
109			*/
110	schoenebeck	2581	virtual int maxAllowedArgs() const = 0;
111	schoenebeck	2612
112			/**
113			* Script data type of the function's @c iArg 'th function argument.
114			* The information provided here is less strong than acceptsArgType().
115			* The parser will compare argument data types provided in scripts by
116			* calling cceptsArgType(). The return value of argType() is used by the
117			* parser instead to show an appropriate parser error which data type
118			* this function usually expects as "default" data type. Reason: a
119			* function may accept multiple data types for a certain function
120			* argument and would automatically cast the passed argument value in
121			* that case to the type it actually needs.
122			*
123			* @param iArg - index of the function argument in question
124			*/
125	schoenebeck	2581	virtual ExprType_t argType(int iArg) const = 0;
126	schoenebeck	2612
127			/**
128			* This function is called by the parser to check whether arguments
129			* passed in scripts to this function are accepted by this function. If
130			* a script calls this function with an argument's data type not
131			* accepted by this function, the parser will throw a parser error.
132			*
133			* @param iArg - index of the function argument in question
134			* @param type - script data type used for this function argument by
135			* currently parsed script
136			*/
137	schoenebeck	2581	virtual bool acceptsArgType(int iArg, ExprType_t type) const = 0;
138	schoenebeck	2612
139			/**
140			* Implements the actual function execution. This function is called by
141			* the VM when this function shall be executed at script runtime.
142			*
143			* @param args - function arguments for executing this built-in function
144			*/
145	schoenebeck	2581	virtual VMFnResult* exec(VMFnArgs* args) = 0;
146	schoenebeck	2612
147			/**
148			* Concenience method for function implementations to show warning
149			* messages.
150			*
151			* @param txt - warning text
152			*/
153	schoenebeck	2598	void wrnMsg(const String& txt);
154	schoenebeck	2612
155			/**
156			* Concenience method for function implementations to show error
157			* messages.
158			*
159			* @param txt - error text
160			*/
161	schoenebeck	2598	void errMsg(const String& txt);
162	schoenebeck	2581	};
163
164	schoenebeck	2594	/**
165			* POD base of VMIntRelPtr and VMInt8RelPtr structures. Not intended to be
166			* used directly. Use VMIntRelPtr or VMInt8RelPtr instead.
167			*/
168			struct VMRelPtr {
169			void** base; ///< Base pointer.
170			int offset; ///< Offset (in bytes) to base pointer.
171			};
172
173			/** @brief Pointer to built-in VM integer variable (of C/C++ type int).
174			*
175			* Used for defining built-in integer script variables.
176			*
177			* @b CAUTION: You may only use this class for pointing to C/C++ variables
178			* of type "int" (which on most systems is 32 bit in size). If the C/C++ int
179			* variable you want to reference is only 8 bit in size, then you @b must
180			* use VMInt8RelPtr instead!
181			*
182			* For efficiency reasons the actual native C/C++ int variable is referenced
183			* by two components here. The actual native int C/C++ variable in memory
184			* is dereferenced at VM run-time by taking the @c base pointer dereference
185			* and adding @c offset bytes. This has the advantage that for a large
186			* number of built-in int variables, only one (or few) base pointer need
187			* to be re-assigned before running a script, instead of updating each
188			* built-in variable each time before a script is executed.
189			*
190			* Refer to DECLARE_VMINT() for example code.
191			*
192			* @see VMInt8RelPtr, DECLARE_VMINT()
193			*/
194			struct VMIntRelPtr : VMRelPtr {
195			VMIntRelPtr() {
196			base = NULL;
197			offset = 0;
198			}
199			VMIntRelPtr(const VMRelPtr& data) {
200			base = data.base;
201			offset = data.offset;
202			}
203			virtual int evalInt() { return (int)&((uint8_t*)base)[offset]; }
204			virtual void assign(int i) { (int)&((uint8_t*)base)[offset] = i; }
205			};
206
207			/** @brief Pointer to built-in VM integer variable (of C/C++ type int8_t).
208			*
209			* Used for defining built-in integer script variables.
210			*
211			* @b CAUTION: You may only use this class for pointing to C/C++ variables
212			* of type "int8_t" (8 bit integer). If the C/C++ int variable you want to
213			* reference is an "int" type (which is 32 bit on most systems), then you
214			* @b must use VMIntRelPtr instead!
215			*
216			* For efficiency reasons the actual native C/C++ int variable is referenced
217			* by two components here. The actual native int C/C++ variable in memory
218			* is dereferenced at VM run-time by taking the @c base pointer dereference
219			* and adding @c offset bytes. This has the advantage that for a large
220			* number of built-in int variables, only one (or few) base pointer need
221			* to be re-assigned before running a script, instead of updating each
222			* built-in variable each time before a script is executed.
223			*
224			* Refer to DECLARE_VMINT() for example code.
225			*
226			* @see VMIntRelPtr, DECLARE_VMINT()
227			*/
228			struct VMInt8RelPtr : VMIntRelPtr {
229			VMInt8RelPtr() : VMIntRelPtr() {}
230			VMInt8RelPtr(const VMRelPtr& data) : VMIntRelPtr(data) {}
231			virtual int evalInt() OVERRIDE {
232			return (uint8_t)&((uint8_t*)base)[offset];
233			}
234			virtual void assign(int i) OVERRIDE {
235			(uint8_t)&((uint8_t*)base)[offset] = i;
236			}
237			};
238
239			/**
240			* Convenience macro for initializing VMIntRelPtr and VMInt8RelPtr
241			* structures. Example:
242			* @code
243			* struct Foo {
244			* uint8_t a;
245			* int b;
246			* };
247			*
248			* Foo foo1 = (Foo) { 1, 3000 };
249			* Foo foo2 = (Foo) { 2, 4000 };
250			*
251			* Foo* pFoo;
252			*
253			* VMInt8RelPtr var1 = DECLARE_VMINT(pFoo, class Foo, a);
254			* VMIntRelPtr var2 = DECLARE_VMINT(pFoo, class Foo, b);
255			*
256			* pFoo = &foo1;
257			* printf("%d\n", var1->evalInt()); // will print 1
258			* printf("%d\n", var2->evalInt()); // will print 3000
259			*
260			* pFoo = &foo2;
261			* printf("%d\n", var1->evalInt()); // will print 2
262			* printf("%d\n", var2->evalInt()); // will print 4000
263			* @endcode
264			*/
265			#define DECLARE_VMINT(basePtr, T_struct, T_member) ( \
266			(VMRelPtr) { \
267			(void**) &basePtr, \
268			offsetof(T_struct, T_member) \
269			} \
270			) \
271
272			/** @brief Built-in VM 8 bit integer array variable.
273			*
274			* Used for defining built-in integer array script variables.
275			*/
276			struct VMInt8Array {
277			int8_t* data;
278			int size;
279
280			VMInt8Array() : data(NULL), size(0) {}
281			};
282
283	schoenebeck	2612	/** @brief Provider for built-in script functions and variables.
284			*
285			* Abstract base class defining the interface for all classes which add and
286			* implement built-in script functions and built-in script variables.
287			*/
288	schoenebeck	2581	class VMFunctionProvider {
289			public:
290	schoenebeck	2612	/**
291			* Returns pointer to the built-in function with the given function
292			* name, or NULL if there is no built-in function with that name.
293			*
294			* @param name - function name
295			*/
296	schoenebeck	2581	virtual VMFunction* functionByName(const String& name) = 0;
297	schoenebeck	2612
298			/**
299			* Returns a variable name indexed map of all built-in script variables
300			* which point to native "int" (usually 32 bit) variables.
301			*/
302	schoenebeck	2594	virtual std::map<String,VMIntRelPtr*> builtInIntVariables() = 0;
303	schoenebeck	2612
304			/**
305			* Returns a variable name indexed map of all built-in script variables
306			* which point to native "int8_t" (8 bit) variables.
307			*/
308	schoenebeck	2594	virtual std::map<String,VMInt8Array*> builtInIntArrayVariables() = 0;
309	schoenebeck	2612
310			/**
311			* Returns a variable name indexed map of all built-in constant script
312			* variables, which never change their value at runtime.
313			*/
314	schoenebeck	2594	virtual std::map<String,int> builtInConstIntVariables() = 0;
315	schoenebeck	2581	};
316
317	schoenebeck	2594	/** @brief Execution state of a virtual machine.
318			*
319			* An instance of this abstract base class represents exactly one execution
320			* state of a virtual machine. This encompasses most notably the VM
321	schoenebeck	2612	* execution stack, and VM polyphonic variables. It does not contain global
322			* variable. Global variables are contained in the VMParserContext object.
323			* You might see a VMExecContext object as one virtual thread of the virtual
324			* machine.
325	schoenebeck	2594	*
326	schoenebeck	2612	* In contrast to a VMParserContext, a VMExecContext is not tied to a
327			* ScriptVM instance. Thus you can use a VMExecContext with different
328			* ScriptVM instances, however not concurrently at the same time.
329			*
330	schoenebeck	2594	* @see VMParserContext
331			*/
332	schoenebeck	2581	class VMExecContext {
333			public:
334			virtual ~VMExecContext() {}
335			virtual int suspensionTimeMicroseconds() const = 0;
336			};
337
338			class VMEventHandler {
339			public:
340			virtual String eventHandlerName() const = 0;
341			};
342
343			struct ParserIssue {
344			String txt;
345			int line;
346			ParserIssueType_t type;
347
348			inline void dump() {
349			switch (type) {
350			case PARSER_ERROR:
351			printf("[ERROR] line %d: %s\n", line, txt.c_str());
352			break;
353			case PARSER_WARNING:
354			printf("[Warning] line %d: %s\n", line, txt.c_str());
355			break;
356			}
357			}
358
359			inline bool isErr() const { return type == PARSER_ERROR; }
360			inline bool isWrn() const { return type == PARSER_WARNING; }
361			};
362
363			inline String typeStr(const ExprType_t& type) {
364			switch (type) {
365			case EMPTY_EXPR: return "empty";
366			case INT_EXPR: return "integer";
367			case INT_ARR_EXPR: return "integer array";
368			case STRING_EXPR: return "string";
369			case STRING_ARR_EXPR: return "string array";
370			}
371			return "invalid";
372			}
373
374	schoenebeck	2594	/** @brief Virtual machine representation of a script.
375			*
376			* An instance of this abstract base class represents a parsed script,
377			* translated into a virtual machine. You should first check if there were
378			* any parser errors. If there were any parser errors, you should refrain
379			* from executing the virtual machine. Otherwise if there were no parser
380			* errors (i.e. only warnings), then you might access one of the script's
381			* event handlers by i.e. calling eventHandlerByName() and pass the
382			* respective event handler to the ScriptVM class (or to one of its
383			* descendants) for execution.
384			*
385			* @see VMExecContext
386			*/
387	schoenebeck	2588	class VMParserContext {
388			public:
389			virtual ~VMParserContext() {}
390			virtual std::vector<ParserIssue> issues() const = 0;
391			virtual std::vector<ParserIssue> errors() const = 0;
392			virtual std::vector<ParserIssue> warnings() const = 0;
393			virtual VMEventHandler* eventHandler(uint index) = 0;
394			virtual VMEventHandler* eventHandlerByName(const String& name) = 0;
395			};
396
397	schoenebeck	2581	} // namespace LinuxSampler
398
399			#endif // LS_INSTR_SCRIPT_PARSER_COMMON_H