diff options
Diffstat (limited to 'libxml')
-rw-r--r-- | libxml/CMakeLists.txt | 19 | ||||
-rw-r--r-- | libxml/xml.h | 90 | ||||
-rw-r--r-- | libxml/xml.l | 497 |
3 files changed, 606 insertions, 0 deletions
diff --git a/libxml/CMakeLists.txt b/libxml/CMakeLists.txt new file mode 100644 index 0000000..96c5653 --- /dev/null +++ b/libxml/CMakeLists.txt @@ -0,0 +1,19 @@ +include_directories( + ${PROJECT_SOURCE_DIR}/libxml +) + +add_custom_command( + COMMAND ${PYTHON_EXECUTABLE} ${PROJECT_SOURCE_DIR}/src/scan_states.py ${PROJECT_SOURCE_DIR}/libxml/xml.l > ${GENERATED_SRC}/xml.l.h + DEPENDS ${PROJECT_SOURCE_DIR}/src/scan_states.py ${PROJECT_SOURCE_DIR}/libxml/xml.l + OUTPUT ${GENERATED_SRC}/xml.l.h +) +set_source_files_properties(${GENERATED_SRC}/xml.l.h PROPERTIES GENERATED 1) + +FLEX_TARGET(xml xml.l ${GENERATED_SRC}/xml.cpp COMPILE_FLAGS "${LEX_FLAGS}") + +add_library(xml +${GENERATED_SRC}/xml.cpp +${GENERATED_SRC}/xml.l.h +) + + diff --git a/libxml/xml.h b/libxml/xml.h new file mode 100644 index 0000000..9670837 --- /dev/null +++ b/libxml/xml.h @@ -0,0 +1,90 @@ +#ifndef XML_H +#define XML_H + +/****************************************************************************** + * + * Copyright (C) 1997-2021 by Dimitri van Heesch. + * + * Permission to use, copy, modify, and distribute this software and its + * documentation under the terms of the GNU General Public License is hereby + * granted. No representations are made about the suitability of this software + * for any purpose. It is provided "as is" without express or implied warranty. + * See the GNU General Public License for more details. + * + * Documents produced by Doxygen are derivative works derived from the + * input used in their production; they are not affected by this license. + * + */ + +#include <memory> +#include <functional> +#include <string> +#include <unordered_map> + +/*! @brief Event handlers that can installed by the client and called while parsing a XML document. + */ +class XMLHandlers +{ + public: + using Attributes = std::unordered_map<std::string,std::string>; + using StartDocType = void(); + using EndDocType = void(); + using StartElementType = void(const std::string &,const Attributes &); + using EndElementType = void(const std::string &); + using ErrorType = void(const std::string,int,const std::string &); + using CharsType = void(const std::string &); + + std::function<StartDocType> startDocument; /**< handler invoked at the start of the document */ + std::function<EndDocType> endDocument; /**< handler invoked at the end of the document */ + std::function<StartElementType> startElement; /**< handler invoked when an opening tag has been found */ + std::function<EndElementType> endElement; /**< handler invoked when a closing tag has been found */ + std::function<CharsType> characters; /**< handler invoked when content between tags has been found */ + std::function<ErrorType> error; /**< handler invoked when the parser encounters an error */ + + static std::string value(const Attributes &attrib,const std::string &key) + { + auto it = attrib.find(key); + if (it!=attrib.end()) + { + return it->second; + } + return ""; + } +}; + +class XMLLocator +{ + public: + virtual ~XMLLocator() {} + virtual int lineNr() const = 0; + virtual std::string fileName() const = 0; +}; + +/*! Very basic SAX style parser to parse XML documents. */ +class XMLParser : public XMLLocator +{ + public: + /*! Creates an instance of the parser object. Different instances can run on different + * threads without interference. + * + * @param handlers The event handlers passed by the client. + */ + XMLParser(const XMLHandlers &handlers); + /*! Destructor */ + ~XMLParser(); + + /*! Parses a file gives the contents of the file as a string. + * @param fileName the name of the file, used for error reporting. + * @param inputString the contents of the file as a zero terminated UTF-8 string. + * @param debugEnabled indicates if debugging via -d lex is enabled or not. + */ + void parse(const char *fileName,const char *inputString,bool debugEnabled); + + private: + virtual int lineNr() const override; + virtual std::string fileName() const override; + struct Private; + std::unique_ptr<Private> p; +}; + +#endif diff --git a/libxml/xml.l b/libxml/xml.l new file mode 100644 index 0000000..13ff219 --- /dev/null +++ b/libxml/xml.l @@ -0,0 +1,497 @@ +/****************************************************************************** + * + * Copyright (C) 1997-2020 by Dimitri van Heesch. + * + * Permission to use, copy, modify, and distribute this software and its + * documentation under the terms of the GNU General Public License is hereby + * granted. No representations are made about the suitability of this software + * for any purpose. It is provided "as is" without express or implied warranty. + * See the GNU General Public License for more details. + * + * Documents produced by Doxygen are derivative works derived from the + * input used in their production; they are not affected by this license. + * + */ +/****************************************************************************** + * Minimal flex based parser for XML + ******************************************************************************/ + +%option never-interactive +%option prefix="xmlYY" +%option reentrant +%option extra-type="struct xmlYY_state *" +%option 8bit noyywrap +%top{ +#include <stdint.h> +} + +%{ + +#include <ctype.h> +#include <vector> +#include <stdio.h> +#include "xml.h" +//#include "message.h" + +#define YY_NEVER_INTERACTIVE 1 +#define YY_NO_INPUT 1 +#define YY_NO_UNISTD_H 1 + +struct xmlYY_state +{ + std::string fileName; + int lineNr = 1; + const char * inputString = 0; //!< the code fragment as text + yy_size_t inputPosition = 0; //!< read offset during parsing + std::string name; + bool isEnd = false; + bool selfClose = false; + std::string data; + std::string attrValue; + std::string attrName; + XMLHandlers::Attributes attrs; + XMLHandlers handlers; + int cdataContext; + int commentContext; + char stringChar; + std::vector<std::string> xpath; +}; + +#if USE_STATE2STRING +static const char *stateToString(int state); +#endif + +static yy_size_t yyread(yyscan_t yyscanner,char *buf,yy_size_t max_size); +static void initElement(yyscan_t yyscanner); +static void addCharacters(yyscan_t yyscanner); +static void addElement(yyscan_t yyscanner); +static void addAttribute(yyscan_t yyscanner); +static void countLines(yyscan_t yyscanner, const char *txt,yy_size_t len); +static void reportError(yyscan_t yyscanner, const std::string &msg); +static std::string processData(yyscan_t yyscanner,const char *txt,yy_size_t len); + +#undef YY_INPUT +#define YY_INPUT(buf,result,max_size) result=yyread(yyscanner,buf,max_size); + +%} + +NL (\r\n|\r|\n) +SP [ \t\r\n]+ +OPEN {SP}?"<" +OPENSPECIAL {SP}?"<?" +CLOSE ">"{NL}? +CLOSESPECIAL "?>"{NL}? +NAMESTART [:A-Za-z\200-\377_] +NAMECHAR [:A-Za-z\200-\377_0-9.-] +NAME {NAMESTART}{NAMECHAR}* +ESC "&#"[0-9]+";"|"&#x"[0-9a-fA-F]+";" +COLON ":" +PCDATA [^<]+ +COMMENT {OPEN}"!--" +COMMENTEND "--"{CLOSE} +STRING \"([^"&]|{ESC})*\"|\'([^'&]|{ESC})*\' +DOCTYPE {SP}?"<!DOCTYPE"{SP} +CDATA {SP}?"<![CDATA[" +ENDCDATA "]]>" + +%option noyywrap + +%s Initial +%s Content +%s CDataSection +%s Element +%s Attributes +%s AttributeValue +%s AttrValueStr +%s Prolog +%s Comment + +%% + +<Initial>{ + {SP} { countLines(yyscanner,yytext,yyleng); } + {DOCTYPE} { countLines(yyscanner,yytext,yyleng); } + {OPENSPECIAL} { countLines(yyscanner,yytext,yyleng); BEGIN(Prolog); } + {OPEN} { countLines(yyscanner,yytext,yyleng); + initElement(yyscanner); + BEGIN(Element); } + {COMMENT} { yyextra->commentContext = YY_START; + BEGIN(Comment); + } +} +<Content>{ + {CDATA} { countLines(yyscanner,yytext,yyleng); + yyextra->cdataContext = YY_START; + BEGIN(CDataSection); + } + {PCDATA} { yyextra->data += processData(yyscanner,yytext,yyleng); } + {OPEN} { countLines(yyscanner,yytext,yyleng); + addCharacters(yyscanner); + initElement(yyscanner); + BEGIN(Element); + } + {COMMENT} { yyextra->commentContext = YY_START; + countLines(yyscanner,yytext,yyleng); + BEGIN(Comment); + } +} +<Element>{ + "/" { yyextra->isEnd = true; } + {NAME} { yyextra->name = yytext; + BEGIN(Attributes); } + {CLOSE} { addElement(yyscanner); + countLines(yyscanner,yytext,yyleng); + yyextra->data = ""; + BEGIN(Content); + } + {SP} { countLines(yyscanner,yytext,yyleng); } +} +<Attributes>{ + "/" { yyextra->selfClose = true; } + {NAME} { yyextra->attrName = yytext; } + "=" { BEGIN(AttributeValue); } + {CLOSE} { addElement(yyscanner); + countLines(yyscanner,yytext,yyleng); + yyextra->data = ""; + BEGIN(Content); + } + {SP} { countLines(yyscanner,yytext,yyleng); } +} +<AttributeValue>{ + {SP} { countLines(yyscanner,yytext,yyleng); } + ['"] { yyextra->stringChar = *yytext; + yyextra->attrValue = ""; + BEGIN(AttrValueStr); + } + . { std::string msg = std::string("Missing attribute value. Unexpected character `")+yytext+"` found"; + reportError(yyscanner,msg); + unput(*yytext); + BEGIN(Attributes); + } +} +<AttrValueStr>{ + [^'"\n]+ { yyextra->attrValue += processData(yyscanner,yytext,yyleng); } + ['"] { if (*yytext==yyextra->stringChar) + { + addAttribute(yyscanner); + BEGIN(Attributes); + } + else + { + yyextra->attrValue += processData(yyscanner,yytext,yyleng); + } + } + \n { yyextra->lineNr++; yyextra->attrValue+=' '; } +} +<CDataSection>{ + {ENDCDATA} { BEGIN(yyextra->cdataContext); } + [^]\n]+ { yyextra->data += yytext; } + \n { yyextra->data += yytext; + yyextra->lineNr++; + } + . { yyextra->data += yytext; } +} +<Prolog>{ + {CLOSESPECIAL} { countLines(yyscanner,yytext,yyleng); + BEGIN(Initial); + } + [^?\n]+ { } + \n { yyextra->lineNr++; } + . { } +} +<Comment>{ + {COMMENTEND} { countLines(yyscanner,yytext,yyleng); + BEGIN(yyextra->commentContext); + } + [^\n-]+ { } + \n { yyextra->lineNr++; } + . { } +} +\n { yyextra->lineNr++; } +. { std::string msg = "Unexpected character `"; + msg+=yytext; + msg+="` found"; + reportError(yyscanner,msg); + } + +%% + +//---------------------------------------------------------------------------------------- + +static yy_size_t yyread(yyscan_t yyscanner,char *buf,size_t max_size) +{ + struct yyguts_t *yyg = (struct yyguts_t*)yyscanner; + yy_size_t inputPosition = yyextra->inputPosition; + const char *s = yyextra->inputString + inputPosition; + yy_size_t c=0; + while( c < max_size && *s) + { + *buf++ = *s++; + c++; + } + yyextra->inputPosition += c; + return c; +} + +static void countLines(yyscan_t yyscanner, const char *txt,yy_size_t len) +{ + struct yyguts_t *yyg = (struct yyguts_t*)yyscanner; + for (yy_size_t i=0;i<len;i++) + { + if (txt[i]=='\n') yyextra->lineNr++; + } +} + +static void initElement(yyscan_t yyscanner) +{ + struct yyguts_t *yyg = (struct yyguts_t*)yyscanner; + yyextra->isEnd = false; // true => </tag> + yyextra->selfClose = false; // true => <tag/> + yyextra->name = ""; + yyextra->attrs.clear(); +} + +static void checkAndUpdatePath(yyscan_t yyscanner) +{ + struct yyguts_t *yyg = (struct yyguts_t*)yyscanner; + if (yyextra->xpath.empty()) + { + std::string msg = "found closing tag '"+yyextra->name+"' without matching opening tag"; + reportError(yyscanner,msg); + } + else + { + std::string expectedTagName = yyextra->xpath.back(); + if (expectedTagName!=yyextra->name) + { + std::string msg = "Found closing tag '"+yyextra->name+"' that does not match the opening tag '"+expectedTagName+"' at the same level"; + reportError(yyscanner,msg); + } + else // matching end tag + { + yyextra->xpath.pop_back(); + } + } +} + +static void addElement(yyscan_t yyscanner) +{ + struct yyguts_t *yyg = (struct yyguts_t*)yyscanner; + if (!yyextra->isEnd) + { + yyextra->xpath.push_back(yyextra->name); + if (yyextra->handlers.startElement) + { + yyextra->handlers.startElement(yyextra->name,yyextra->attrs); + } + if (yy_flex_debug) + { + fprintf(stderr,"%d: startElement(%s,attr=[",yyextra->lineNr,yyextra->name.data()); + for (auto attr : yyextra->attrs) + { + fprintf(stderr,"%s='%s' ",attr.first.c_str(),attr.second.c_str()); + } + fprintf(stderr,"])\n"); + } + } + if (yyextra->isEnd || yyextra->selfClose) + { + if (yy_flex_debug) + { + fprintf(stderr,"%d: endElement(%s)\n",yyextra->lineNr,yyextra->name.data()); + } + checkAndUpdatePath(yyscanner); + if (yyextra->handlers.endElement) + { + yyextra->handlers.endElement(yyextra->name); + } + } +} + +static std::string trimSpaces(const std::string &str) +{ + const int l = static_cast<int>(str.length()); + int s=0, e=l-1; + while (s<l && isspace(str.at(s))) s++; + while (e>s && isspace(str.at(e))) e--; + return str.substr(s,1+e-s); +} + +static void addCharacters(yyscan_t yyscanner) +{ + struct yyguts_t *yyg = (struct yyguts_t*)yyscanner; + std::string data = trimSpaces(yyextra->data); + if (yyextra->handlers.characters) + { + yyextra->handlers.characters(data); + } + if (!data.empty()) + { + if (yy_flex_debug) + { + fprintf(stderr,"characters(%s)\n",data.c_str()); + } + } +} + +static void addAttribute(yyscan_t yyscanner) +{ + struct yyguts_t *yyg = (struct yyguts_t*)yyscanner; + yyextra->attrs.insert(std::make_pair(yyextra->attrName,yyextra->attrValue)); +} + +static void reportError(yyscan_t yyscanner,const std::string &msg) +{ + struct yyguts_t *yyg = (struct yyguts_t*)yyscanner; + if (yy_flex_debug) + { + fprintf(stderr,"%s:%d: Error '%s'\n",yyextra->fileName.c_str(),yyextra->lineNr,msg.c_str()); + } + if (yyextra->handlers.error) + { + yyextra->handlers.error(yyextra->fileName,yyextra->lineNr,msg); + } +} + +static const char *entities_enc[] = { "amp", "quot", "gt", "lt", "apos" }; +static const char entities_dec[] = { '&', '"', '>', '<', '\'' }; +static const int num_entities = 5; + +// replace character entities such as & in txt and return the string where entities +// are replaced +static std::string processData(yyscan_t yyscanner,const char *txt,yy_size_t len) +{ + std::string result; + result.reserve(len); + for (yy_size_t i=0; i<len; i++) + { + char c = txt[i]; + if (c=='&') + { + const int maxEntityLen = 10; + char entity[maxEntityLen+1]; + entity[maxEntityLen]='\0'; + for (yy_size_t j=0; j<maxEntityLen && i+j+1<len; j++) + { + if (txt[i+j+1]!=';') + { + entity[j]=txt[i+j+1]; + } + else + { + entity[j]=0; + break; + } + } + bool found=false; + for (int e=0; !found && e<num_entities; e++) + { + if (strcmp(entity,entities_enc[e])==0) + { + result+=entities_dec[e]; + i+=strlen(entities_enc[e])+1; + found=true; + } + } + if (!found) + { + std::string msg = std::string("Invalid character entity '&") + entity + ";' found\n"; + reportError(yyscanner,msg); + } + } + else + { + result+=c; + } + } + return result; +} + +//-------------------------------------------------------------- + +struct XMLParser::Private +{ + yyscan_t yyscanner; + struct xmlYY_state xmlYY_extra; +}; + +XMLParser::XMLParser(const XMLHandlers &handlers) : p(new Private) +{ + xmlYYlex_init_extra(&p->xmlYY_extra,&p->yyscanner); + p->xmlYY_extra.handlers = handlers; +} + +XMLParser::~XMLParser() +{ + xmlYYlex_destroy(p->yyscanner); +} + +void XMLParser::parse(const char *fileName,const char *inputStr, bool debugEnabled) +{ + yyscan_t yyscanner = p->yyscanner; + struct yyguts_t *yyg = (struct yyguts_t*)yyscanner; + +#ifdef FLEX_DEBUG + xmlYYset_debug(1,p->yyscanner); +#endif + + if (inputStr==nullptr || inputStr[0]=='\0') return; // empty input + + FILE *output = 0; + const char *enter_txt = 0; + const char *finished_txt = 0; + const char *pre_txt = 0; + if (yy_flex_debug) { output=stderr; pre_txt="--"; enter_txt="entering"; finished_txt="finished"; } + else if (debugEnabled) { output=stdout; pre_txt=""; enter_txt="Entering"; finished_txt="Finished"; } + + if (output) + { + fprintf(output,"%s%s lexical analyzer: %s (for: %s)\n",pre_txt,enter_txt, __FILE__, fileName); + } + + BEGIN(Initial); + yyextra->fileName = fileName; + yyextra->lineNr = 1; + yyextra->inputString = inputStr; + yyextra->inputPosition = 0; + + xmlYYrestart( 0, yyscanner ); + + if (yyextra->handlers.startDocument) + { + yyextra->handlers.startDocument(); + } + xmlYYlex(yyscanner); + if (yyextra->handlers.endDocument) + { + yyextra->handlers.endDocument(); + } + + if (!yyextra->xpath.empty()) + { + std::string tagName = yyextra->xpath.back(); + std::string msg = "End of file reached while expecting closing tag '"+tagName+"'"; + reportError(yyscanner,msg); + } + + if (output) + { + fprintf(output,"%s%s lexical analyzer: %s (for: %s)\n",pre_txt,finished_txt, __FILE__, fileName); + } +} + +int XMLParser::lineNr() const +{ + struct yyguts_t *yyg = (struct yyguts_t*)p->yyscanner; + return yyextra->lineNr; +} + +std::string XMLParser::fileName() const +{ + struct yyguts_t *yyg = (struct yyguts_t*)p->yyscanner; + return yyextra->fileName; +} + +#if USE_STATE2STRING +#include "xml.l.h" +#endif |