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Implement a new stack and error handling model for the SourcePawn VM.

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This has three major changes to SourcePawn. First, the API now supports the concept of "exceptions". The exception state is a global property of an instance of the SourcePawn VM. Exceptions can be caught or suppressed. Many places in SourceMod have been updated to check exceptions instead of errors.

The new API obsoletes major parts of the embedder API - all but one method of invoking functions is obsoleted, and the debug interface has been scrapped. Extensions using the native API will not be affected, however, ThrowNativeError has been deprecated in favor of ReportError.

Second, the SourcePawn concept of a "stack" has been unified at the API level. A stack frame iterator now iterates over all SourcePawn invocations, rather than the topmost plugin. This makes error handling more consistent and removes another dependency on context-per-plugin.

Finally, the implementation of stack frames has been changed dramatically. Rather than maintain a complicated and expensive return pointer stack, we now rely on the implicit one provided by the CPU. The stack frame iterator now walks the JIT stack directly. This removes many unnecessary bookkeeping instructions from the generated code, in particular making the CALL instruction 40% faster.

These changes required some fair surgery to the JIT. Its error paths are now slightly more complicated, as they have to throw an exception rather than return an error code. In addition, any path that can throw an exception is now responsible for creating an "exit frame", which exists to tell the stack frame iterator about transitions from the JIT to the VM.
This commit is contained in:
David Anderson
2015-03-04 23:45:30 -08:00
parent 04827466b0
commit a1afa23bc4
51 changed files with 2085 additions and 1766 deletions
Download Patch File Download Diff File Expand all files Collapse all files
public/INativeInvoker.h
-107
View File
@@ -1,107 +0,0 @@
/**
* vim: set ts=4 :
* =============================================================================
* SourceMod
* Copyright (C) 2004-2009 AlliedModders LLC. All rights reserved.
* =============================================================================
*
* This program is free software; you can redistribute it and/or modify it under
* the terms of the GNU General Public License, version 3.0, as published by the
* Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*
* As a special exception, AlliedModders LLC gives you permission to link the
* code of this program (as well as its derivative works) to "Half-Life 2," the
* "Source Engine," the "SourcePawn JIT," and any Game MODs that run on software
* by the Valve Corporation. You must obey the GNU General Public License in
* all respects for all other code used. Additionally, AlliedModders LLC grants
* this exception to all derivative works. AlliedModders LLC defines further
* exceptions, found in LICENSE.txt (as of this writing, version JULY-31-2007),
* or <http://www.sourcemod.net/license.php>.
*
* Version: $Id$
*/
#ifndef _INCLUDE_SOURCEMOD_INATIVEINVOKER_H_
#define _INCLUDE_SOURCEMOD_INATIVEINVOKER_H_
/**
* @file INativeInvoker.h
* @brief Interface for invoking natives.
*/
#include <IShareSys.h>
#include <sp_vm_api.h>
#define SMINTERFACE_NINVOKE_NAME "INativeInterface"
#define SMINTERFACE_NINVOKE_VERSION 1
#define NINVOKE_DEFAULT_MEMORY 16384
namespace SourceMod
{
class INativeInvoker : public SourcePawn::ICallable
{
public:
/**
* @brief Virtual destructor - use delete to free this.
*/
virtual ~INativeInvoker()
{
}
public:
/**
* @brief Begins a native call.
*
* During a call's preparation, no new calls may be started.
*
* @param pContext Context to invoke native under.
* @param name Name of native.
* @return True if native was found, false otherwise.
*/
virtual bool Start(SourcePawn::IPluginContext *pContext, const char *name) = 0;
/**
* @brief Invokes the native. The preparation state is cleared immediately, meaning that
* this object can be re-used after or even from inside the native being called.
*
* @param result Optional pointer to retrieve a result.
* @return SP_ERROR return code.
*/
virtual int Invoke(cell_t *result) = 0;
};
/**
* @brief Factory for dealing with native invocations.
*/
class INativeInterface : public SMInterface
{
public:
/**
* @brief Creates a virtual plugin. This can be used as an environment to invoke natives.
*
* IPluginRuntime objects must be freed with the delete operator.
*
* @param name Name, or NULL for anonymous.
* @param bytes Number of bytes for memory (NINVOKE_DEFAULT_MEMORY recommended).
* @return New runtime, or NULL on failure.
*/
virtual SourcePawn::IPluginRuntime *CreateRuntime(const char *name, size_t bytes) = 0;
/**
* @brief Creates an object that can be used to invoke a single native code.
*
* @return New native invoker (free with delete).
*/
virtual INativeInvoker *CreateInvoker() = 0;
};
}
#endif /* _INCLUDE_SOURCEMOD_INATIVEINVOKER_H_ */
public/amtl/am-fixedarray.h
+4
View File
@@ -85,6 +85,10 @@ class FixedArray : public AllocPolicy
data_[index] = t;
}
T *buffer() const {
return data_;
}
private:
FixedArray(const FixedArray &other) KE_DELETE;
FixedArray &operator =(const FixedArray &other) KE_DELETE;
public/jit/assembler.h
+12 -1
View File
@@ -230,13 +230,24 @@ class Label
assert(this->offset() == offset);
}
private:
protected:
// Note that 0 as an invalid offset is okay, because the offset we save for
// pending jumps are after the jump opcode itself, and therefore 0 is never
// valid, since there are no 0-byte jumps.
uint32_t status_;
};
// Label that suppresses its assert, for non-stack use.
class SilentLabel : public Label
{
public:
SilentLabel()
{}
~SilentLabel() {
status_ = 0;
}
};
// A DataLabel is a special form of Label intended for absolute addresses that
// are within the code buffer, and thus aren't known yet, and will be
// automatically fixed up when calling emitToExecutableMemory().
public/sourcepawn/sp_vm_api.h
+361 -119
View File
@@ -1,4 +1,4 @@
// vim: set sts=2 ts=8 sw=2 tw=99 et:
// vim: set ts=4 sw=4 tw=99 noet:
//
// Copyright (C) 2006-2015 AlliedModders LLC
//
@@ -19,15 +19,19 @@
*/
#include <stdio.h>
#include <assert.h>
#include "sp_vm_types.h"
/** SourcePawn Engine API Versions */
#define SOURCEPAWN_ENGINE2_API_VERSION 9
#define SOURCEPAWN_API_VERSION 0x0209
#define SOURCEPAWN_ENGINE2_API_VERSION 0xA
#define SOURCEPAWN_API_VERSION 0x020A
namespace SourceMod {
struct IdentityToken_t;
};
namespace sp {
class Environment;
};
struct sp_context_s;
typedef struct sp_context_s sp_context_t;
@@ -36,6 +40,8 @@ namespace SourcePawn
{
class IVirtualMachine;
class IPluginRuntime;
class ISourcePawnEngine2;
class ISourcePawnEnvironment;
/* Parameter flags */
#define SM_PARAM_COPYBACK (1<<0) /**< Copy an array/reference back after call */
@@ -162,21 +168,23 @@ namespace SourcePawn
* @brief Executes the function, resets the pushed parameter list, and
* performs any copybacks.
*
* The exception state is reset upon entering and leaving this
* function. Callers that want to propagate exceptions from Execute()
* should use Invoke(). ReportError is not preferred since it would
* lose any custom exception messages.
*
* @param result Pointer to store return value in.
* @return Error code, if any.
*/
virtual int Execute(cell_t *result) =0;
/**
* @brief Executes the function with the given parameter array.
* Parameters are read in forward order (i.e. index 0 is parameter #1)
* NOTE: You will get an error if you attempt to use CallFunction() with
* previously pushed parameters.
* @brief This function is deprecated. If invoked, it reports an error.
*
* @param params Array of cell parameters.
* @param num_params Number of parameters to push.
* @param result Pointer to store result of function on return.
* @return SourcePawn error code (if any).
* @param params Unused.
* @param num_params Unused.
* @param result Unused.
* @return SP_ERROR_ABORTED.
*/
virtual int CallFunction(const cell_t *params, unsigned int num_params, cell_t *result) =0;
@@ -204,30 +212,22 @@ namespace SourcePawn
virtual funcid_t GetFunctionID() =0;
/**
* @brief Executes the forward, resets the pushed parameter list, and
* performs any copybacks.
* @brief This function is deprecated. If invoked, it reports an error.
*
* Note: A function can only be executed given a runtime it was created in.
*
* @param ctx Context to execute the function in.
* @param result Pointer to store return value in.
* @return Error code, if any.
* @param ctx Unused.
* @param result Unused.
* @return SP_ERROR_ABORTED.
*/
virtual int Execute2(IPluginContext *ctx, cell_t *result) =0;
/**
* @brief Executes the function with the given parameter array.
* Parameters are read in forward order (i.e. index 0 is parameter #1)
* NOTE: You will get an error if you attempt to use CallFunction() with
* previously pushed parameters.
* @brief This function is deprecated. If invoked, it reports an error.
*
* Note: A function can only be executed given a runtime it was created in.
*
* @param ctx Context to execute the function in.
* @param params Array of cell parameters.
* @param num_params Number of parameters to push.
* @param result Pointer to store result of function on return.
* @return SourcePawn error code (if any).
* @param ctx Unused.
* @param params Unused.
* @param num_params Unused.
* @param result Unused.
* @return SP_ERROR_ABORTED.
*/
virtual int CallFunction2(IPluginContext *ctx,
const cell_t *params,
@@ -240,6 +240,20 @@ namespace SourcePawn
* @return IPluginRuntime pointer.
*/
virtual IPluginRuntime *GetParentRuntime() =0;
/**
* @brief Executes the function, resets the pushed parameter list, and
* performs any copybacks.
*
* Unlike Execute(), this does not reset the exception state. It is
* illegal to call Invoke() while an exception is unhandled. If it
* returns false, an exception has been thrown, and must either be
* handled via ExceptionHandler or propagated to its caller.
*
* @param result Pointer to store return value in.
* @return True on success, false on error.
*/
virtual bool Invoke(cell_t *rval = nullptr) = 0;
};
@@ -309,7 +323,7 @@ namespace SourcePawn
*
* @param index Unused.
* @param native Unused.
* @return Returns SP_ERROR_PARAM.
* @return Returns SP_ERROR_PARAM.
*/
virtual int GetNativeByIndex(uint32_t index, sp_native_t **native) =0;
@@ -409,7 +423,7 @@ namespace SourcePawn
/**
* @brief If |co| is non-NULL, destroys |co|. No other action is taken.
*
* @return Returns SP_ERROR_NONE.
* @return Returns SP_ERROR_NONE.
*/
virtual int ApplyCompilationOptions(ICompilation *co) =0;
@@ -448,13 +462,13 @@ namespace SourcePawn
*/
virtual unsigned char *GetDataHash() =0;
/**
* @brief Update the native binding at the given index.
*
* @param pfn Native function pointer.
* @param flags Native flags.
* @param user User data pointer.
*/
/**
* @brief Update the native binding at the given index.
*
* @param pfn Native function pointer.
* @param flags Native flags.
* @param user User data pointer.
*/
virtual int UpdateNativeBinding(uint32_t index, SPVM_NATIVE_FUNC pfn, uint32_t flags, void *data) = 0;
/**
@@ -464,6 +478,11 @@ namespace SourcePawn
* @return Native pointer, or NULL on failure.
*/
virtual const sp_native_t *GetNative(uint32_t index) = 0;
/**
* @brief Return the file or location this plugin was loaded from.
*/
virtual const char *GetFilename() = 0;
};
/**
@@ -559,7 +578,7 @@ namespace SourcePawn
*
* @param index Unused.
* @param native Unused.
* @return Returns SP_ERROR_PARAM.
* @return Returns SP_ERROR_PARAM.
*/
virtual int GetNativeByIndex(uint32_t index, sp_native_t **native) =0;
@@ -734,6 +753,8 @@ namespace SourcePawn
/**
* @brief Throws a error and halts any current execution.
*
* This function is deprecated. Use ReportError() instead.
*
* @param error The error number to set.
* @param msg Custom error message format. NULL to use default.
* @param ... Message format arguments, if any.
@@ -744,6 +765,8 @@ namespace SourcePawn
/**
* @brief Throws a generic native error and halts any current execution.
*
* This function is deprecated. Use ReportError() instead.
*
* @param msg Custom error message format. NULL to set no message.
* @param ... Message format arguments, if any.
* @return 0 for convenience.
@@ -816,14 +839,13 @@ namespace SourcePawn
virtual IPluginRuntime *GetRuntime() =0;
/**
* @brief Executes a function in the context. The function must be
* a member of the context's parent runtime.
* @brief This function is deprecated. If invoked, it reports an error.
*
* @param function Function.
* @param params Parameters.
* @param num_params Number of parameters in the parameter array.
* @param result Optional pointer to store the result on success.
* @return Error code.
* @param function Unused.
* @param params Unused.
* @param num_params Unused.
* @param result Unused.
* @return SP_ERROR_ABORTED.
*/
virtual int Execute2(IPluginFunction *function,
const cell_t *params,
@@ -832,9 +854,12 @@ namespace SourcePawn
/**
* @brief Returns whether a context is in an error state.
*
* This function is deprecated. Use DetectExceptions instead.
*
* This should only be used inside natives to determine whether
* a prior call failed.
* a prior call failed. The return value should only be compared
* against SP_ERROR_NONE.
*/
virtual int GetLastNativeError() =0;
@@ -870,81 +895,171 @@ namespace SourcePawn
virtual bool GetKey(int k, void **value) =0;
/**
* @brief Clears the last native error.
* @brief If an exception is pending, this removes the exception. It
* is deprecated and should not be used.
*/
virtual void ClearLastNativeError() =0;
};
/**
* @brief Return a pointer to the ISourcePawnEngine2 that is active.
* This is a convenience function.
*
* @return API pointer.
*/
virtual ISourcePawnEngine2 *APIv2() = 0;
/**
* @brief Information about a position in a call stack.
*/
struct CallStackInfo
{
const char *filename; /**< NULL if not found */
unsigned int line; /**< 0 if not found */
const char *function; /**< NULL if not found */
/**
* @brief Report an error.
*
* @param message Error message format.
* @param ... Formatting arguments.
*/
virtual void ReportError(const char *fmt, ...) = 0;
/**
* @brief Report an error with variadic arguments.
*
* @param message Error message format.
* @param ap Formatting arguments.
*/
virtual void ReportErrorVA(const char *fmt, va_list ap) = 0;
/**
* @brief Report a fatal error. Fatal errors cannot be caught by any
* exception handler.
*
* @param message Error message format.
* @param ... Formatting arguments.
*/
virtual void ReportFatalError(const char *fmt, ...) = 0;
/**
* @brief Report a fatal error with variadic arguments. Fatal errors
* cannot be caught by any exception handler.
*
* @param message Error message format.
* @param ap Formatting arguments.
*/
virtual void ReportFatalErrorVA(const char *fmt, va_list ap) = 0;
/**
* @brief Report an error by its builtin number.
*
* @param number Error number.
*/
virtual void ReportErrorNumber(int error) = 0;
};
/**
* @brief Retrieves error information from a debug hook.
* @brief Removed.
*/
class IContextTrace
class IContextTrace;
/**
* @brief Information about a reported error.
*/
class IErrorReport
{
public:
/**
* @brief Returns the integer error code.
* @brief Return the message of the error report.
*
* @return Integer error code.
* @return Message string.
*/
virtual int GetErrorCode() =0;
virtual const char *Message() const = 0;
/**
* @brief Returns a string describing the error.
* @brief True if the error is fatal and cannot be handled (though
* reporting can be suppressed).
*
* @return Error string.
* @return True if fatal, false otherwise.
*/
virtual const char *GetErrorString() =0;
virtual bool IsFatal() const = 0;
/**
* @brief Returns whether debug info is available.
* @brief Return the plugin context that caused the error.
*
* @return True if debug info is available, false otherwise.
* @return Plugin context.
*/
virtual bool DebugInfoAvailable() =0;
/**
* @brief Returns a custom error message.
*
* @return A pointer to a custom error message, or NULL otherwise.
*/
virtual const char *GetCustomErrorString() =0;
/**
* @brief Returns trace info for a specific point in the backtrace, if any.
* The next subsequent call to GetTraceInfo() will return the next item in the call stack.
* Calls are retrieved in descending order (i.e. the first item is at the top of the stack/call sequence).
*
* @param trace An ErrorTraceInfo buffer to store information (NULL to ignore).
* @return True if successful, false if there are no more traces.
*/
virtual bool GetTraceInfo(CallStackInfo *trace) =0;
/**
* @brief Resets the trace to its original position (the call on the top of the stack).
*/
virtual void ResetTrace() =0;
/**
* @brief Retrieves the name of the last native called.
* Returns NULL if there was no native that caused the error.
*
* @param index Optional pointer to store index.
* @return Native name, or NULL if none.
*/
virtual const char *GetLastNative(uint32_t *index) =0;
virtual IPluginContext *Context() const = 0;
};
/**
* @brief Allows inspecting the stack frames of the SourcePawn environment.
*
* Invoking VM functions while iterating frames will cause the iterator
* to become corrupt.
*
* Frames iterate in most-recent to least-recent order.
*/
class IFrameIterator
{
public:
/**
* @brief Returns whether or not there are more frames to read.
*
* @return True if there are more frames to read, false otherwise.
*/
virtual bool Done() const = 0;
/**
* @brief Advances to the next frame.
*
* Note that the iterator starts at either a valid frame or no frame.
*/
virtual void Next() = 0;
/**
* @brief Resets the iterator to the top of the stack.
*/
virtual void Reset() = 0;
/**
* @brief Returns the context owning the current frame, if any.
*
* @return Context, or null.
*/
virtual IPluginContext *Context() const = 0;
/**
* @brief Returns whether or not the current frame is a native frame. If it
* is, line numbers and file paths are not available.
*
* @return True if a native frame, false otherwise.
*/
virtual bool IsNativeFrame() const = 0;
/**
* @brief Returns true if the frame is a scripted frame.
*
* @return True if a scripted frame, false otherwise.
*/
virtual bool IsScriptedFrame() const = 0;
/**
* @brief Returns the line number of the current frame, or 0 if none is
* available.
*
* @return Line number on success, 0 on failure.
*/
virtual unsigned LineNumber() const = 0;
/**
* @brief Returns the function name of the current frame, or null if
* none could be computed.
*
* @return Function name on success, null on failure.
*/
virtual const char *FunctionName() const = 0;
/**
* @brief Returns the file path of the function of the current frame,
* or none could be computed.
*
* @return File path on success, null on failure.
*/
virtual const char *FilePath() const = 0;
};
/**
* @brief Provides callbacks for debug information.
@@ -953,12 +1068,13 @@ namespace SourcePawn
{
public:
/**
* @brief Invoked on a context execution error.
* @brief No longer invoked.
*
* @param ctx Context.
* @param error Object holding error information and a backtrace.
* @param ctx Unused.
* @param error Unused.
*/
virtual void OnContextExecuteError(IPluginContext *ctx, IContextTrace *error) =0;
virtual void OnContextExecuteError(IPluginContext *ctx, IContextTrace *error)
{}
/**
* @brief Called on debug spew.
@@ -967,6 +1083,15 @@ namespace SourcePawn
* @param fmt Message formatting arguments (printf-style).
*/
virtual void OnDebugSpew(const char *msg, ...) =0;
/**
* @brief Called when an error is reported and no exception
* handler was available.
*
* @param report Error report object.
* @param iter Stack frame iterator.
*/
virtual void ReportError(const IErrorReport &report, IFrameIterator &iter) = 0;
};
/**
@@ -983,21 +1108,21 @@ namespace SourcePawn
/**
* @brief Return the name of the profiling tool.
*
* @return Profiling tool name.
* @return Profiling tool name.
*/
virtual const char *Name() = 0;
/**
* @brief Description of the profiler.
*
* @return Description.
* @return Description.
*/
virtual const char *Description() = 0;
/**
* @brief Called to render help text.
*
* @param render Function to render one line of text.
* @param render Function to render one line of text.
*/
virtual void RenderHelp(void (*render)(const char *fmt, ...)) = 0;
@@ -1013,7 +1138,7 @@ namespace SourcePawn
/**
* @brief Initiate a stop command.
*
* @param render Function to render any help messages.
* @param render Function to render any help messages.
*/
virtual void Stop(void (*render)(const char *fmt, ...)) = 0;
@@ -1029,14 +1154,14 @@ namespace SourcePawn
/**
* @brief Returns whether or not the profiler is currently profiling.
*
* @return True if active, false otherwise.
* @return True if active, false otherwise.
*/
virtual bool IsActive() = 0;
/**
* @brief Returns whether the profiler is attached.
*
* @return True if attached, false otherwise.
* @return True if attached, false otherwise.
*/
virtual bool IsAttached() = 0;
@@ -1045,8 +1170,8 @@ namespace SourcePawn
*
* LeaveScope() mus be called exactly once for each call to EnterScope().
*
* @param group A named budget group, or NULL for the default.
* @param name Event name.
* @param group A named budget group, or NULL for the default.
* @param name Event name.
*/
virtual void EnterScope(const char *group, const char *name) = 0;
@@ -1114,10 +1239,10 @@ namespace SourcePawn
virtual void ExecFree(void *address) =0;
/**
* @brief Sets the debug listener. This should only be called once.
* If called successively (using manual chaining), only the last function should
* attempt to call back into the same plugin. Otherwise, globally cached states
* can be accidentally overwritten.
* @brief Sets the debug listener.
*
* This should be called once on application startup. It is
* not considered part of the userland API and may change at any time.
*
* @param listener Pointer to an IDebugListener.
* @return Old IDebugListener, or NULL if none.
@@ -1166,6 +1291,8 @@ namespace SourcePawn
virtual void FreePageMemory(void *ptr) =0;
};
class ExceptionHandler;
/**
* @brief Outlines the interface a Virtual Machine (JIT) must expose
*/
@@ -1228,10 +1355,10 @@ namespace SourcePawn
virtual void DestroyFakeNative(SPVM_NATIVE_FUNC func) =0;
/**
* @brief Sets the debug listener. This should only be called once.
* If called successively (using manual chaining), only the last function should
* attempt to call back into the same plugin. Otherwise, globally cached states
* can be accidentally overwritten.
* @brief Sets the debug listener.
*
* This should be called once on application startup. It is
* not considered part of the userland API and may change at any time.
*
* @param listener Pointer to an IDebugListener.
* @return Old IDebugListener, or NULL if none.
@@ -1248,6 +1375,9 @@ namespace SourcePawn
/**
* @brief Returns the string representation of an error message.
*
* This function is deprecated and should not be used. The exception
* handling API should be used instead.
*
* @param err Error code.
* @return Error string, or NULL if not found.
*/
@@ -1326,6 +1456,11 @@ namespace SourcePawn
* @return New runtime pointer, or NULL on failure.
*/
virtual IPluginRuntime *LoadBinaryFromFile(const char *file, char *error, size_t maxlength) = 0;
/**
* @brief Returns the environment.
*/
virtual ISourcePawnEnvironment *Environment() = 0;
};
// @brief This class is the v3 API for SourcePawn. It provides access to
@@ -1351,6 +1486,23 @@ namespace SourcePawn
// all plugin memory. This should not be called while plugins have
// active code running on the stack.
virtual void Shutdown() = 0;
// @brief Enters an exception handling scope. This is intended to be
// used on the stack and must have a corresponding call to
// LeaveExceptionHandlingScope. When in an exception handling scope,
// exceptions are not immediately reported. Instead the caller is
// responsible for propagation them or clearing them.
virtual void EnterExceptionHandlingScope(ExceptionHandler *handler) = 0;
// @brief Leaves the most recent exception handling scope. The handler
// is provided as a sanity check.
virtual void LeaveExceptionHandlingScope(ExceptionHandler *handler) = 0;
// @brief Returns whether or not an exception is currently pending.
virtual bool HasPendingException(const ExceptionHandler *handler) = 0;
// @brief Returns the message of the pending exception.
virtual const char *GetPendingExceptionMessage(const ExceptionHandler *handler) = 0;
};
// @brief This class is the entry-point to using SourcePawn from a DLL.
@@ -1371,6 +1523,96 @@ namespace SourcePawn
// @brief A function named "GetSourcePawnFactory" is exported from the
// SourcePawn DLL, conforming to the following signature:
typedef ISourcePawnFactory *(*GetSourcePawnFactoryFn)(int apiVersion);
// @brief A helper class for handling exceptions.
//
// ExceptionHandlers can be used to detect, catch, and re-throw VM errors
// within C++ code.
//
// When throwing errors, SourcePawn creates an exception object. The
// exception object is global state. As long as an exception is present,
// all scripted code should immediately abort and return to their callers,
// all native code should exit, all code should propagate any error states
// until the exception is handled.
//
// In some cases, an error code is not available. For example, if a native
// detects an exception, it does not have an error status to propagate. It
// should simply return instead. The return value will be ignored; the VM
// knows to abort the script.
class ExceptionHandler
{
friend class sp::Environment;
public:
ExceptionHandler(ISourcePawnEngine2 *api)
: env_(api->Environment()),
catch_(true)
{
env_->EnterExceptionHandlingScope(this);
}
ExceptionHandler(IPluginContext *ctx)
: env_(ctx->APIv2()->Environment()),
catch_(true)
{
env_->EnterExceptionHandlingScope(this);
}
~ExceptionHandler()
{
env_->LeaveExceptionHandlingScope(this);
}
virtual uint32_t ApiVersion() const {
return SOURCEPAWN_API_VERSION;
}
// Propagates the exception instead of catching it. After calling this,
// no more SourcePawn code should be executed until the exception is
// handled. Callers should return immediately.
void Rethrow() {
assert(catch_ && HasException());
catch_ = false;
}
bool HasException() const {
return env_->HasPendingException(this);
}
const char *Message() const {
return env_->GetPendingExceptionMessage(this);
}
private:
// Don't allow heap construction.
ExceptionHandler(const ExceptionHandler &other);
void operator =(const ExceptionHandler &other);
void *operator new(size_t size);
void operator delete(void *, size_t);
private:
ISourcePawnEnvironment *env_;
ExceptionHandler *next_;
protected:
// If true, the exception will be swallowed.
bool catch_;
};
// @brief An implementation of ExceptionHandler that simply collects
// whether an exception was thrown.
class DetectExceptions : public ExceptionHandler
{
public:
DetectExceptions(ISourcePawnEngine2 *api)
: ExceptionHandler(api)
{
catch_ = false;
}
DetectExceptions(IPluginContext *ctx)
: ExceptionHandler(ctx)
{
catch_ = false;
}
};
};
#endif //_INCLUDE_SOURCEPAWN_VM_API_H_
public/sourcepawn/sp_vm_types.h
+3
View File
@@ -88,6 +88,9 @@ typedef uint32_t funcid_t; /**< Function index code */
#define SP_ERROR_OUT_OF_MEMORY 28 /**< Out of memory */
#define SP_ERROR_INTEGER_OVERFLOW 29 /**< Integer overflow (-INT_MIN / -1) */
#define SP_ERROR_TIMEOUT 30 /**< Timeout */
#define SP_ERROR_USER 31 /**< Custom message */
#define SP_ERROR_FATAL 32 /**< Custom fatal message */
#define SP_MAX_ERROR_CODES 33
//Hey you! Update the string table if you add to the end of me! */
/**********************************************