WO2008110111A1

WO2008110111A1 - Method and device to call dynamic library and dynamic library server and master program implementing device

Info

Publication number: WO2008110111A1
Application number: PCT/CN2008/070462
Authority: WO
Inventors: Zhen Liang; Chunfeng Xie; Qingfeng Deng; Jing Wang; Weibao Luo; Xiaochuan Ke; Chenming Liu
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2007-03-13
Filing date: 2008-03-11
Publication date: 2008-09-18
Also published as: CN101021804A; CN100464305C

Abstract

A method and device to call the dynamic library, and the dynamic library server and the master program implementing device are disclosed, relating to the operation system, for resolving the problem of prone to making mistake when calling the dynamic library which is a part of master program, and the poor portability. The method to call the dynamic library includes: the dynamic library server receives the request information of calling the function in the dynamic library sent from the master program, the request information carries the parameter of the calling function; the dynamic library server returns the function executing result to the master program in the response information according to the function in the parameter call dynamic library. The method and device to call the dynamic library, and the dynamic library server are applicable to calling the dynamic library by the master program in any operation systems.

Description

Method, device and dynamic library server and main program execution device for calling dynamic library

The present invention relates to the field of operating systems, and in particular, to a method, apparatus, and dynamic library server and main program execution apparatus for calling a dynamic library.

Background technique

As an indispensable part of the operating system structure, dynamic libraries are used to decompose a complex program into multiple different parts and provide them to different developers/factories.

Currently, the way to call a dynamic library is usually to put the dynamic library and the executable program on a computer, link when compiling the executable program, or load the specified file when the executable program runs, thereby implementing the executable program to call the dynamic library. The function of one or more functions in . Regardless of whether the link is used or dynamically loaded, the dynamic library is loaded as part of the executable, loaded into an address space of the executable, and called as if it were a native function.

However, in the process of implementing the present invention, the inventors have found that the use of existing such dynamic libraries has also brought about some problems. The first is that it may cause instability in the main program. Because the dynamic library may be provided by a third party, it is difficult for the provider of the main program to control its quality. Serious defects such as memory leaks and pointer abnormal access may occur in the dynamic library, which will directly cause the main program to run abnormally. And once the main program is abnormal, the location of the problem is more difficult due to its complicated and large structure.

Second, existing dynamic libraries cannot be flexibly configured. Based on the main program of an operating system, it can only call the dynamic library under the system. If you want to call the dynamic library under other operating systems, you need to recompile and port the dynamic library to the operating system. Sometimes it is possible to recompile a dynamic library even when the main program is based on a different version of the operating system or compiler. Also, if a main program under Windows is to be ported to Unix, its corresponding dynamic library must be migrated at the same time, otherwise the program will not work properly, and vice versa.

Summary of the invention In view of this, the purpose of the embodiments of the present invention is to provide a method for calling a dynamic library, which is used to accurately locate problems when an abnormality occurs in a dynamic library, and improve portability of the dynamic library.

Another object of embodiments of the present invention is to provide an apparatus for invoking a dynamic library for improving the accuracy of dynamic library problem location and portability of dynamic libraries.

A third object of the embodiments of the present invention is to provide a dynamic library server for implementing separation of a main program from a dynamic library function call.

A fourth object of the embodiments of the present invention is to provide a main program execution apparatus for realizing separation of a main program from a dynamic library function call.

An embodiment of the present invention provides a method for invoking a dynamic library, including: a dynamic library server receiving a request message sent by a main program and calling a function in a dynamic library, where the request message carries a parameter of a calling function;

The dynamic library server calls the function in the dynamic library according to the parameter, and returns the function execution result to the main program in the response message.

An embodiment of the present invention further provides an apparatus for calling a dynamic library, including:

a main program execution unit, configured to send a request message for calling a function in a dynamic library, where the request message carries a parameter of the calling function;

a dynamic library server, configured to complete a function of the function in the dynamic library unit according to the parameter, and return an execution result of the function to the main program execution unit in the response message;

The dynamic library unit is configured to run the function according to the call request of the dynamic library server, and report the execution result to the dynamic library server.

An embodiment of the present invention further provides a dynamic library server, including:

a message processing module, configured to receive a request message sent by the main program and carrying a parameter of the calling function, and send a call instruction according to the parameter; return the execution result to the main program through the response message; and call the module, according to the call The function name and the parameter list in the instruction call the corresponding function, and the execution result of the function is reported to the message processing module.

An embodiment of the present invention further provides a main program execution apparatus, including: a request message sending module, configured to send, to the dynamic library server, a request message for calling a function in the dynamic library, where the request message carries a parameter of the calling function;

And a receiving module, configured to receive, by the dynamic database server, a function in the dynamic library according to the parameter, and return a response message carrying the result of the function execution to the main program.

The embodiment of the present invention executes the calling of the main program to the dynamic library through the dynamic library server, and uses the message mechanism to transfer parameters and data between the main program and the dynamic library server, thereby realizing that the error of the dynamic library only affects the dynamic library server. And the main program only obtains the error information in the response message, and does not affect the operation of the main program; on the other hand, since the main program and the dynamic library server are two independent individuals, the embodiment of the present invention allows the main program Compared with the dynamic library server based on different operating systems, it can be set on different computers, which improves the portability of dynamic libraries.

DRAWINGS

1 is a flowchart of a method for calling a dynamic library in an embodiment of the present invention;

2 is a schematic diagram showing the relationship between a main program, a dynamic library server, and a dynamic library in an embodiment of the present invention;

FIG. 3 is a structural diagram of an apparatus for calling a dynamic library in an embodiment of the present invention.

detailed description

The embodiment of the present invention executes the calling of the main program to the dynamic library through the dynamic library server, and uses the message mechanism to transfer parameters and data between the main program and the dynamic library server, so that the error of the dynamic library only affects the dynamic library server. The main program only obtains the error information in the response message, and does not affect the operation of the main program; on the other hand, since the main program and the dynamic library server are two independent individuals, the embodiment of the present invention allows the main program and The dynamic library server can be set on different computers based on different operating systems, which improves the portability of dynamic libraries. Moreover, when the main program is transplanted to other systems for execution, it is not necessary to transplant all the dynamic libraries. Reduced product migration time.

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail with reference to the accompanying drawings. As shown in FIG. 1 , it is a flowchart of a method for calling a dynamic library in an embodiment of the present invention. The method may be divided into two parts: an initialization and a function call, and specifically includes the following steps:

Step 101: The dynamic library server loads the dynamic library. The dynamic library server starts after the deployment is complete, and the step is executed at startup to get the dynamic library that it manages.

In the current common operating systems Windows and Unix, the statements used to load the dynamic library function are different. In Windows systems, the load library function is used, while on Unix systems, the dlopen function is used. By executing the load statement, the dynamic library server obtains a handle to its own managed dynamic library.

In the embodiment of the present invention, the dynamic library server and the dynamic library loaded thereon can be set on the same device, because the load library function and the dlopen function can only be loaded based on the existing Windows and Unix operating system architecture. A dynamic library of local computers.

Step 102: The main program requests to obtain a dynamic library list that the dynamic library server has successfully loaded.

In an embodiment of the invention, the dynamic library server is capable of loading and managing multiple dynamic libraries. By performing step 101, the dynamic library server obtains the handles of all the dynamic libraries managed by itself, and at this time, the main program does not know which dynamic library is specifically loaded by the dynamic library server, so this step is used to obtain the successfully loaded. Dynamic library list.

Step 103: The dynamic library server returns a dynamic library list that has been successfully loaded to the main program. The list contains the names of the loaded dynamic libraries, such as a.dll, b.dll and other dynamic libraries.

In the embodiment of the present invention, the relationship between the main program and the dynamic library server is many-to-many, that is, one main program can send a function call request to multiple dynamic library servers, and a dynamic library managed by a dynamic library server can be Called by the main program. The relationship between the main program, the dynamic library server, and the dynamic library is shown in Figure 2. The main program 1 can call the dynamic library servers 1, 2 and n, and the dynamic library managed by the dynamic library server 1 includes a.dll, and so on.

Through the above steps, the initialization of the dynamic library server is completed, and the main program also obtains a list of dynamic libraries that each dynamic library server loads successfully. The following process is to execute a specific function call. Step 104: The main program calls to call a function in the dynamic library. Suppose that the func function in the a.dll dynamic library is called here, a.dll is the dynamic library name, and funcl is the function name.

Step 105: The main program sends a request message of the function call to the dynamic library server. The request message carries a parameter of the calling function, and the parameter includes a dynamic library name, a function name, and a parameter list.

The main program refers to the dynamic library list, and sends a request message to the dynamic library server to which the a.dll dynamic library belongs, and the message carries the dynamic library name, the function name, and the parameter list. The parameter list includes the type, length, and parameter values of each parameter.

In the actual application process, when the main program sends a function call request to the dynamic library server, the called function may have a sequential relationship in the dynamic library. For example, some dynamic libraries require an initialization (init) function to complete the function of allocating the buffer (buffer), initializing variables, and then calling the execute (exe) function to complete the function call. For these two functions, the execution order is fixed, that is, the init function must be called before the exe function. If the function is not initialized and the exe is called directly, the execution of the function will be wrong. Another situation is that a state is stored in the dynamic library. Calls of different functions will cause changes to the state, such as opening the file (open), writing (do), and closing the file (close). Open a file, execute do to write to the file, and execute close to close the file. If the execution order is wrong, it will inevitably lead to failure of the file operation. The correct execution order is guaranteed by the user of the dynamic library. The user cannot decide the problem. When the functions with sequential execution order are assigned to different dynamic library servers, for example, the init function and the exe function are assigned. Different dynamic library servers, even if the user calls these two functions in the correct order, the two call requests are sent to different dynamic library servers. The dynamic library server executing the init function obtains the handle of the function, but calls exe Another dynamic library server for the function cannot execute the function correctly because there is no such function handle. The same is true for file operations. If the three functions open, do, and close are managed by different dynamic library servers, and these dynamic library servers may be set on different physical devices, then even if the users are called in the correct order. These three functions, these functions also cannot target the same file Take action.

In order to solve the foregoing problems, embodiments of the present invention propose a concept of a session group, which sets a set of functions having successive calling relationships as a session, having the same session-id, and a group having the same session-id. The function is loaded into the dynamic library list of the same dynamic library server, and is saved and managed by the dynamic library server. When the main program calls the set of functions having successive calling relationships, the main program sends a call request to the same dynamic library server according to the session_id of the function.

Step 106: After receiving the request message, the dynamic library server invokes the corresponding function execution according to the dynamic library name and the function name.

The statements of the dynamic library server calling function based on different operating systems are different. The Windows and Unix operating systems are still taken as an example. In the Windows system, the dynamic library server obtains the result obtained in step 101 according to the name of the dynamic library a.dll. The handle of the dynamic library and the function name to be called are input parameters, using the get proc address statement. On Unix systems, the dlsym statement is used. After executing the statement, the dynamic library server obtains the address of the function to be called. Based on this address, the dynamic library server executes the function using the parameters of the corresponding function in the request message as input parameters. When executed correctly, the dynamic library server obtains the execution result and output parameter list of the function.

Step 107: The dynamic library server returns a response message to the main program, where the message carries the execution result of the function. The execution result includes a return value of the function execution and a list of output parameters.

In the embodiment of the present invention, since the main program and the dynamic library server transmit data by using a message mechanism, the two can be set on the same computer or on different computers. When set up on different computers, the two deliver messages over a network connection. The data transmitted in the network connection uses the network byte order, and the endian used by different operating systems may be different from the network byte order. Take the Windows operating system as an example. The trick is to use the Windows byte order with the opposite network byte order. Assuming that the network byte order of the four-byte data is 01, 02, 03, 04, the Windows byte order is 04, 03, 02, 01. When non-network byte order data is transmitted in the network, it will cause transmission errors; similarly, when the main program is based on the operating system and the dynamic library server is based on When the operating system uses different endianness, it will also cause errors in the data received by the peer. In order to solve the above problem, the embodiment of the present invention uses a scheme in which the byte order of data is unified as a network endian when the main program is used as a transmitting end or a dynamic library server, that is, at the sending end of the message. Cast the endianness of the data into a network endian.

Specifically, it includes: If the operating system of the sending end uses Windows byte order, and the transmitted data has an explicit parameter type, such as a single-byte integer, a single-byte integer pointer, and a two-byte integer (short), Two-byte integer pointer (short*), four-byte integer (long), four-byte integer pointer (long*), double-precision floating-point (double), double-precision floating-point pointer (double*) , the operating system uses a specific conversion statement, such as for short and short * data, using htons statement to convert to network byte order, for long and long * data, using htonl statement conversion. After the network byte order data is transferred to the peer, if the peer supports Windows byte order, the byte order of the data is also restored by the ntohs and ntohl statements. The conversion mode is implemented by the message mechanism. When the sender constructs the message, it determines whether the parameter or data carried in the message is of the foregoing type. If yes, it converts it into a network byte order through the corresponding statement, and the receiving end receives the message. After the message, the parameters or data are converted to the native byte order as needed.

However, in practical applications, there is another case where the transmitted data has no explicit parameter type, and the dynamic library and the dynamic library user use a non-universal endian. At this point, the user of the dynamic library and the dynamic library agree on the implementation of the endian. E.g:

Struct MYSTRUCT *pstr = (struct MYSTRUCT *)pStruct;

The function of the struct MYSTRUCT * statement is to cast the parameter pStmct to the MYSTRUCT structure agreed by the dynamic library and the user. This conversion is done at the transmitting end and the endian is restored at the receiving end. Unsigned short usReal Value;

Memcpy(&usRealValue,pStmct,sizeof(usRealValue))

The function of the memcpy statement is to copy the contents of one buffer to another. Among the three input parameters, the first two parameters are the buffer address, and the third parameter is the size of the copied content. The usRealValue is short and has a size of 2 bytes, so the 2-byte data in the pStmct buffer is copied into usRealValue, which also converts the data type of the pStmct buffer to the data type of the usRealValue buffer.

Through the above method, the conversion of the network byte order and the non-network byte order is realized, and the accuracy of the network data transmission between the main program and the dynamic library server is ensured to some extent.

Using the method of calling the dynamic library as shown in Figure 1, it can be called by the main program regardless of the system environment of the dynamic library, making the overall architecture of the system more flexible. If the main program is ported to a different operating system for market demand, using the method shown in Figure 1, it avoids the problem that the third-party dynamic library is not transplanted and the program cannot run, thus reducing The migration risks of different manufacturers' products, and because some dynamic libraries are not transplanted, also save the product migration time. Because of the compatibility problem, some technologies are difficult to be ported to other operating systems, such as Com technology under Windows. At this time, they can be made into dynamic libraries and still run under Windows system. This reduces the technical risk of product migration.

In addition, using the method shown in Figure 1, the exception of the dynamic library does not affect the main program, ensuring the stability of the main program running. Since the dynamic library is loaded and executed by the dynamic library server, even if the dynamic inventory is executed incorrectly, the error is transferred to the dynamic library server, and the main program only receives the error response message, and the main program is not caused by the error. The operation is abnormal, and through the error response message, the main program can accurately know which dynamic library has an error, thereby realizing rapid fault location. Finally, since there may be multiple dynamic library servers in the embodiment of the present invention, one of the exceptions does not affect other dynamic database servers, which also ensures the stability of the service operation.

As shown in FIG. 3, a device structure diagram for calling a dynamic library in an embodiment of the present invention specifically includes: a main program execution unit 31, configured to invoke a function in a dynamic library by sending a request message during a process of running a main program. The request message carries a parameter of the calling function.

The dynamic library server 32 is configured to complete the calling of the function according to the parameter, and return a function execution result and an output parameter to the main program execution unit in the response message;

The dynamic library unit 33 is configured to run the function according to the request of the dynamic library server 32, and report the function execution result and the output parameter to the dynamic library server.

The main program execution unit 31 and the dynamic library server 32 may be disposed on different computer devices, and the dynamic library server 32 and the dynamic library 33 are disposed on the same computer device.

The dynamic library server 32 may specifically include:

The loading module 321 is configured to load the dynamic library managed by the dynamic library server to the local when the dynamic library server starts. The load module loads the dynamic library when the dynamic library server starts, and the result of the loading is to obtain the handle of the dynamic library. And through the initialization process, the list of dynamically loaded dynamic libraries is sent to the main program.

The message processing module 322 is configured to receive a request message sent by the main program execution unit, and send a call instruction according to the dynamic library name, the function name, and the parameter list carried in the message; and return the execution result and the output parameter of the function through the response message. The unit is executed by the main program. In the process of message creation, the end program is converted by the main program module and the message processing module, and the parameters or data are transmitted using a unified network byte order.

The calling module 323 is configured to invoke a corresponding function according to the function name and the parameter list in the calling instruction, and report the execution result and the return parameter to the message processing module.

For the sake of simplicity, in FIG. 3, only the internal structure of one dynamic library server is described, and the other is the same, and the correspondence between the main program execution unit, the dynamic library server, and the dynamic library is similar to that of FIG. 2. The device for calling the dynamic library provided by the embodiment of the present invention performs the calling of the main program to the dynamic library through the dynamic library server, and the message system and the dynamic database server use the message mechanism to transmit parameters and data, thereby realizing the dynamic library. The error only affects the dynamic library server, and the main program only gets the error information in the response message, which does not affect the running of the main program. On the other hand, since the main program and the dynamic library server are two independent individuals, The device for calling the dynamic library provided by the embodiment of the present invention allows the main program and the dynamic library server to be set on different computers based on different operating systems, thereby improving the portability of the dynamic library.

In another embodiment of the present invention, a dynamic library server is provided, including:

a loading module, configured to load a dynamic library managed by itself to a local device at startup, and return a list of dynamically loaded dynamic libraries to the main program;

a message processing module, configured to receive a request message sent by the main program, and send a call instruction according to a parameter such as a dynamic library name, a function name, and a parameter list of the function carried in the message; returning the execution result of the function to the main program through the response message ;

The calling module is configured to invoke a corresponding function according to the function name and the parameter list in the calling instruction, and report the execution result and the output parameter to the message processing module.

The implementation of the dynamic library server adopts a modular manner, and the functions and structures are relatively simple, and can be easily compiled and executed under different operating systems, so that dynamic libraries under different operating systems are It can be loaded by the corresponding dynamic library server, which realizes the purpose that different dynamic libraries can be called by the main program under various system environments.

In a further embodiment of the present invention, a main program execution apparatus is provided, including: a request message sending module, configured to send a request message to a dynamic library server to call a function in a dynamic library, where the request message carries a call The argument of the function;

The main program execution device achieves the purpose of separating the main program from the dynamic library function by sending a request message to the dynamic library server and calling a function in the dynamic library. When the dynamic library has an error, Does not affect the operation of the main program.

In the dynamic library server provided by the embodiment of the present invention, the calling of the main program to the dynamic library is performed by the dynamic library server, and the parameter and the data are transmitted between the main program and the dynamic database server, thereby realizing the error of the dynamic library. Will affect the dynamic library server, and the main program only gets error information in the response message, does not affect the operation of the main program; on the other hand, since the main program and the dynamic library server are two independent individuals, the present invention The dynamic library server provided by the embodiment allows the main program and the dynamic library server to be set on different computers based on different operating systems, thereby improving the portability of the dynamic library.

The above is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any technical person skilled in the art can disclose the technical scope of the present invention and the technical idea of the present invention. Variations or substitutions that are conceivable within the scope of the invention are intended to be included within the scope of the invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

Claim

A method for calling a dynamic library, comprising:

The dynamic library server receives a request message sent by the main program and calls a function in the dynamic library, where the request message carries a parameter of the calling function;

2. The method of calling a dynamic library according to claim 1, further comprising the steps of: loading, by the dynamic library server, a dynamic library managed by the dynamic library server itself at startup, and according to the main program Request, return to the main program a list of dynamically loaded libraries.

The method for calling a dynamic library according to claim 2, wherein the dynamic library server sets a plurality of function calls having successive calling relationships in the same session group when loading the dynamic library managed by the dynamic library server. Multiple calls belonging to the same session group are only sent to the same dynamic library server.

4. The method of calling a dynamic library according to claim 1, wherein the carried parameter comprises a dynamic library name, a function name, and a parameter list of the function.

The method of calling a dynamic library according to any one of claims 1 to 4, wherein the returning the function execution result to the main program further comprises:

The dynamic library server returns the output parameters of the function execution to the main program through the response message.

The method for calling a dynamic library according to claim 5, wherein a function return value and a parameter carried in the request message and the response message use a network byte order, when the main program or the dynamic When the library server uses non-network byte order, the function return value and parameters are converted to network byte order.

7. The method of calling a dynamic library according to claim 6, wherein the converting the function return value and the parameter into a network byte order comprises the following steps:

The function return value and the parameter have an explicit parameter type, and the dynamic byte server or the main program's message sending and receiving mechanism completes the conversion of the native byte order and the network byte order; or The return value and the parameter do not have an explicit parameter type, and the user of the dynamic library negotiates with the dynamic library to realize the unification of the endian.

8. A device for invoking a dynamic library, comprising:

a main program execution unit, configured to send a request message for calling a function in the dynamic library, where the request message carries a parameter of the calling function;

a dynamic library server, configured to complete a function call in the dynamic library unit according to the parameter, and return an execution result of the function to the main program execution unit in the response message;

a dynamic library unit, configured to run the function according to the call request of the dynamic library server, and report the execution result to the dynamic library server.

The device for invoking a dynamic library according to claim 8, wherein the dynamic library server comprises:

a loading module, configured to load a dynamic library managed by the dynamic library server to the local site when the dynamic library server starts;

a message processing module, configured to receive a request message sent by the main program execution unit, and send a call instruction according to the dynamic library name, the function name, and the parameter list carried in the message; return the execution result and the output parameter of the function to the response message The main program execution unit;

The calling module is configured to call a corresponding function according to the function name and the parameter list in the calling instruction, and report the execution result and the return parameter to the message processing module.

10. The apparatus for calling a dynamic library according to claim 8 or 9, wherein the main program execution unit calls one or more dynamic library servers, and the dynamic library server manages one or more dynamic libraries. unit.

The apparatus for calling a dynamic library according to claim 8 or 9, wherein the dynamic library server and the dynamic library are disposed on the same computer.

12. A dynamic library server, comprising:

a message processing module, configured to receive a request message sent by the main program and carry a parameter of the calling function, and send a call instruction according to the parameter; return the execution result to the main program through the response message; The calling module is configured to invoke a corresponding function according to the function name and the parameter list in the calling instruction, and report the execution result of the function to the message processing module.

The dynamic library server according to claim 12, further comprising: a loading module, configured to load the dynamic library managed by itself to the local at startup.

14. A main program execution device, comprising:

a request message sending module, configured to send, to the dynamic library server, a request message for calling a function in the dynamic library, where the request message carries a parameter of the calling function;

The receiving module is configured to receive a response message that the dynamic library server invokes a function in the dynamic library according to the parameter, and returns a result of carrying the function execution to the main program.