88 results about "C programming language" patented technology

The invention discloses an Android application reinforcing method based on C source code mixing. The method comprises writing program key codes by using C programming languages and mixing C source codes. The reinforcement of Android application is achieved by mixing the C source codes in the Android application program, and the Android application program codes are protected. The Android application reinforcing method based on C source code mixing specifically includes the steps of writing the key part of the program by using C programming languages, writing programs into .so dynamic-link library file, invoking the dynamic-link library by using JNI technology in Java language, and then mixing the C source codes, so as to achieve the reinforcement of Android application. According to the Android application reinforcing method based on C source code mixing, important codes are saved in the C dynamic-link library by adopting NDK programming, and then the C source codes are mixed, the software protection is improved. At the same time, the important codes are written in a so library, the reusability of the codes are increased, ready-made so library can be directly introduced into other applications, so as to eliminate the troubles of secondary development.

The invention relates to a static analysis-based checking method of safety rules of C language, which comprises the following steps: 1) checking the type of the C language to avoid the occurrence of compulsory type conversion and prohibiting the declaration of the type of a generic pointer; 2) stipulating that a global variable and a local variable can not be in homonymy, and the global variable and a formal parameter of a function can not be in tautonomy; 3) limiting a cyclic variable of a control flow statement; 4) strengthening the declaration and the definition of the C language; and 5) carrying out analysis of accidence, grammar and semanteme on source codes, and finding out places which do not meet the stipulation from the source codes. The method has the advantages of being capable of finding out possible loopholes on programming of the C language under the premise that the codes do not need to be executed and effectively making up for the deficiency of insufficient safety of the C language in soft engineering.

The invention relates to an automatic code generation method from AADL to C language. The method comprises the following steps that 1, a transformational rule from an AADL meta model to the C language is defined according to the semantic meaning of the AADL meta model, the semantic meaning of an object run environment and the grammar semantic meaning of the C language; 2, an automatic code generation template is made according to the adopted meta model capable of being obtained by an AADL model, the semantic meaning of the meta model and the transformational rule from the AADL meta model to the C language; 3, a template transformation engine is compiled according to the automatic code generation template; 4, after the AADL model is input, the input AADL model is automatically analyzed, and information of the AADL meta model is extracted, and is generated into C language codes through the template transformation template according to the automatic code generation template. The method has the following advantages that the transformational rule from the AADL meta model to the C language is defined, and semantic mapping of the AADL and the C language is effectively achieved; the code transformation efficiency is improved through the template engine.

The invention relates to the electronic field of autocar, and the whole circuit adopts regional design, altogether divided into power supply region, microprocessor region, input region, output region, communication debugging region and failure diagnosis region, and other functional regions. By loading the application software of the controlled object of the autocar, and inputting the needed input signals, it can control the target actuator based on the given control policy and makes on-line failure diagnosis on all the sensors and actuators, able to implement the development and design of autocar engine management system, auto gear box control system, ABS control system, autocar body control system, instrument and information system, and other electronic control systems. And the user only need possess the basis of C language so as to be able to make functional operation on all the interfaces and it can provide a friendly development environment of electronic control system for autocar and engine engineers of nonelectornic and computer specialties.

The invention relates to a computer language transformation system. The computer language transformation system is used for transforming C language program into MSVL (Modeling, Simulation and Verification Language) program, and comprises a lexical analysis module, a syntax analysis module and a transformation processing module, wherein the lexical analysis module is used for transforming character sequences into word sequences; the character sequences comprise definitions of key words, identification characters, constants, operators, header files and comment lines in C language; the syntax analysis module is used for identifying specific sentences in C language based on related lexical rules of C language specified in yacc (Yet Another Compiler Compiler); and the transformation processing module is used for transforming C language into MSVL language according to a language transformation rule between C language and MSVL language.

An algorithm C description describing an algorithm of computation or control of a logic circuit in a C language is split into a plurality of states in units of processing, and the execution order of the split processing is described as state transition, to generate a functional C description with a control description embedded therein. A clock description as the conception of time is inserted in the functional C description, to be converted into a RT level C description. The RT level C description is converted into a RT level description in HDL with an existing conversion tool.

The invention discloses a video key frame extraction algorithm, and belongs to the technical field of information security. According to the algorithm, firstly the black border width of the horizontaldirection and the black border height of the vertical direction of a certain frame in the current input video stream and the width and height of the effective image area of the frame are calculated;then the feature information of the effective image area of the frame is calculated and compared with that of the last frame so as to calculate the degree of difference; when the degree of differenceis greater than the threshold, the data in the difference frame are compared with each frame of data of a cache area so as to calculate the similarity of the frame; and when the similarity of the difference frame is greater than the threshold, the difference frame is regarded to be similar to the certain frame in the cache area, one non-difference frame is added, the maximum cumulative number of the non-difference frame is reached, the frame is outputted as the difference frame and written in the cache area, statistics of the variance value of the Y value and the variance value of the UY valueof the frame is performed and the key frame and the blank frame are outputted. The algorithm is realized by the C programming language and can be applied to multi-video and multi-thread calling so that the algorithm is high in adaptability and efficient and rapid.

In one embodiment, an improved programming system and language for application development is provided that combines elements of the C and Objective-C languages without the constraints imposed by a requirement to maintain compatibility with the C language. The language provides the functionality of the C language compatibility in certain areas to improve the inherent safety of software written in the language. The new language includes default safety considerations such as bounds and overflow checking.

A dual-chaotic system dynamic key and RSA jointed streaming media secret communication method relates to the technical field of communication encryption and solve the problem of certain potential safety hazards and poor secrecy of streaming media communication due to the fact that the root key is not effectively protected in the network transmission process of streaming media communication. Chaotic system parameters, iterative step length generated in a chaotic sequence and the preset iteration times serve as dynamic parameters, values meeting the conditions are generated randomly before each communication and form the root key, and the root key is subject to secrecy synchronization through the RSA algorithm. Difference of root keys makes the chaotic key sequences used for each encryption and deception are different. Meanwhile, the chaotic key sequences are formed by interweaving combination of two hyper-chaotic sequences so the chaotic key sequences are more complicated. The dual-chaotic system dynamic key and RSA jointed streaming media secret communication method reduces the generating time of the chaotic key sequences and improves the encryption speed. Testing of software written through C programming language in the local area network proves that the dual-chaotic system dynamic key and RSA jointed streaming media secret communication method can meet requirements of streaming media communication for safety and timeliness.

The embodiment of the invention discloses an embedded multimedia playing system. The embedded multimedia playing system comprises a foreground interface, a middleware and a background control module, wherein the foreground interface is a graphical user interface based on hypertext markup language (HTML), cascading style sheet (CSS) and JavaScript language; the middleware is based on Qt/Embedded, is used for providing an interface and supporting display output, and is connected with the background control module; the background control module adopts standard C language; and a user inputs information from the graphical user interface, the middleware receives the information input by the user through the interface, and the background control module processes the input information, does corresponding operation and invokes a drive to perform decoding play. The Qt/Embedded serves as the middleware, the graphical user interface and the background control module are separated from the Qt/Embedded frame, the interface for accessing mutually is provided, and background control is realized by using the C language, so the coupling degree of the foreground module and the background module is reduced, the fault tolerance and the stability of the system are improved, and the using efficiency of resources is improved. The invention also discloses an embedded multimedia playing method with high fault tolerance and stability.

The invention discloses an embedded automation development method which comprises the following steps of: parsing a requirement document into a data format which can be understood by python through VB (Visual Basic); translating the generated Python data to generate a related frame code of a C programming language or C++ programming language again by the python according to the actual customization needs, and supplying the frame code to a coder to use; carrying out writing by the coder on the basis of the frame code so as to realize the needed features and functions; uploading the code after writing to a code server to finish a complete code project; formulating a compiling specification and a compiling time of an item through an automatic compiling tool bamboo; if compiling succeeds, generating an executable program, introducing the executable program into a target machine through a script, carrying out automation test based on robot framework, and finally issuing a version through the test; and if the compiling fails, carrying out mail notification on the coder with a revise history on the code server, and in addition, recording an error reason and an error causing person.

The invention provides a C language programming teaching and test comprehensive system and method. The C language programming teaching and test comprehensive system comprises a C language teaching and test server and a plurality of learning machines, the C language teaching and test server is connected with the learning machines through the network to form a C language programming teaching and test integrated platform, exercise and test of C language programming can be achieved for students by means of the C language programming teaching and test integrated platform, examination of the practical programming ability of the students is achieved, the programming environment where the students learn can be standardized and unified, management can be conveniently conducted on every student, and therefore the practical programming ability of the students can be effectively improved.

The invention discloses an instrumentation and dynamic test coverage information extraction method of C-language embedded software. The method comprises the following steps of: regarding a C-language program as an array which is formed by all branch points, wherein each branch point corresponds to an element in the array; defining each element to be in two states, wherein 1 represents that the branch points are executed, and 0 represents that the branch points are unexecuted; defining the array in a special storage area; at each branch point of the C-language program, adding an operation code into a branch point information array which is defined in the special storage area, wherein the operation code is used for outputting information which indicates whether the branch points are executed; executing the C-language program into which the operation code is added, and then extracting the branch point information array from the special storage area; and according to the state of each element in the branch point information array, determining the execution situation of each branch point in the C-language program, and thus obtaining the dynamic test coverage of the C-language program. The instrumentation and dynamic test coverage information extraction method of the C-language embedded software has the characteristics of low code expansion rate, small storage space of branch point information, and convenience for extraction of coverage information.

Provided is a security method for enhancing Java distribution software based on JavaAgent and dll. The security method comprises the following steps that step 1, an encryption program programmed withC language and jar package offline c language encryption program only needing to be released perform encryption operation; and a to-be-encrypted package jar path is transmitted to the encryption program; step 2, the encrypted jar package adds the JavaAgent into a startup script of an application, and after decryption, the JavaAgent is loaded by a Classloader and then operates. Related commands ofthe JavaAgent are used for carrying out decryption work before a jvm is loaded; the JavaAgent is a program performing intercept and modification on byte codes before Java loads a class file, and is connected to an executable file of a jar package address for decryption in a shared function library through a dll dynamic link library.

The invention discloses an alarmed fan module of a temperature-control industrial personal computer (IPC). A single-chip A/D (analog-to-digital) converter, and a pulse width modulator (PWM) and a single-chip selector based on C programming language are arranged in a single-chip; the control module of the single-chip comprises a test circuit composed of thermistors and the single-chip A/D converter, a control circuit composed of the PWM and a chassis fan, and an alarm circuit composed of the single-chip selector, an LED (light-emitting diode) and a buzzer; a 74HC151 chip-selection integrated chip is arranged in the single-chip selector; and the single-chip is a 8-bit single-chip. Since the functional circuits are integrated by the single-chip, and most functions are achieved by the C programming language in the single-chip, the invention has the advantages of simple circuit design, low cost and good performance; and the invention provides an alarm device, thereby better solving the problem that faults occurring to the cooling fan cannot be found in a timely manner and providing reliable guarantee for the safe operation of the IPC.

The invention discloses a method for SWF confusion encryption. The method specifically comprises the following steps: (1) determining a to-be-protected core AS3.0 engineering file source code; (2) compiling a universal confusion class, and confusing the contents of the files in the source packet; (3) compiling the mixed source code into a source SWF file through a Felx SDK; (4) comiling an encryption tool, enabling the encryption tool adopt an encryption method compiled by a C language, and after an SWF file is read according to byte streams, conducting AES encryption on the SWF file; (5) compiling an application for loading the SWF for loading the SWF file generated in the last step; and (6) compiling and publishing the application in the step (5) into a formal SWF file, and externally providing the formal SWF file for a client to use. The method has the beneficial effects that the personal technology is protected from being stolen by a hacker for reuse, byte stream encryption is carried out on the SWF file generated by compiling, and the effects of double encryption and technical privacy protection are achieved.

The invention provides an analysis method for a C language simulation model. A C code analysis method category is generated by grammar files in advance, wherein the C code analysis method category comprises a syntax analysis module, a lexical analysis module and a syntax tree generation module. The method includes the steps that the lexical analysis module in the C code analysis method category is called to analyze lexical content of the imported C language simulation model, so as to form a token flow; the syntax analysis module is called to analyze the syntax content of the imported C language simulation model according to the token flow; the syntax tree generation module is called to generate a corresponding syntax tree according to the syntax content obtained through analysis; and information is extracted from the syntax tree and stored in a model information file. The invention further provides a monitoring method of the C language simulation model. The monitoring method comprises the analysis method. The analysis method and the monitoring method provided by the invention fill in the present blanks in the C language simulation model analysis and monitoring technology in china, and the implementation processes of the analysis method and the monitoring method are simple.

The invention discloses a database server performance evaluation implementation method based on Informix. The C programming language and the SQL are used for development, the method is compatible with host systems of different structures, and a performance evaluation standard model is provided for an Informix data system; the performance evaluation standard model mainly comprises a starting module, a pressure generating module, a result recording module and a performance monitoring module; the performance evaluation method achieves standardization and routinization of an Informix pressure testing model, meanwhile avoids harmful effects on later performance evaluation of complex SQL statements and programmer levels, is convenient to transplant, and is compatible with the host systems of different structures.

This invention discloses a method to use C language non local jump tool analogue abnormal mechanism, which comprises the following steps: in each needed jump flow control point using setjmp to record transfer environment; when the transfer function enters next layer flow to keep front layer transfer environment variable; when executing flow jump, transferring non local jump tool to front record transfer environment.