diff options
Diffstat (limited to 'tkhtml1/tools/sgmlparse.c')
| -rw-r--r-- | tkhtml1/tools/sgmlparse.c | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/tkhtml1/tools/sgmlparse.c b/tkhtml1/tools/sgmlparse.c new file mode 100644 index 0000000..d85806e --- /dev/null +++ b/tkhtml1/tools/sgmlparse.c @@ -0,0 +1,207 @@ +/* +** This file contains code used to tokenize SGML. +*/ +#include <stdio.h> +#include <ctype.h> +#include <string.h> +#include <stdlib.h> +#include <assert.h> +#include "sgmlparse.h" + +#define stricmp strcasecmp + +/* These three pointers define certain special handlers. All whitespace +** is sent to xSpaceHandler. Non-whitespace is given to xWordHandler. +** Any markup that isn't specifically directed elsewhere is given +** to xDefaultMarkupHandlers. +*/ +static void (*xSpaceHandler)(const char*,void*); +static void (*xWordHandler)(const char*,void*); +static void (*xCommentHandler)(const char*,void*); +static void (*xDefaultMarkupHandler)(int, const char**, void*); + +/* Each handler is stored in a hash table as an instance of the +** following structure. +*/ +typedef struct sgHandler Handler; +struct sgHandler { + char *zName; /* Name of markup to handle */ + void (*xHandler)(int, const char**, void*); /* Routine to do the work */ + Handler *pCollide; /* Next handler with same hash */ +}; + +/* The size of the handler hash table. +** For best results, this should be a prime number which is larger than +** the number of markups in the hash table. +*/ +#define SGML_HASH_SIZE 203 + +/* The handler hash table */ +static Handler *apHandler[SGML_HASH_SIZE]; + +/* Hash a handler name */ +static int SgmlHash(const char *zName){ + int h = 0; + char c; + while( (c=*zName)!=0 ){ + if( isupper(c) ) c = tolower(c); + h = h<<5 ^ h ^ c; + zName++; + } + if( h<0 ) h = -h; + return h % SGML_HASH_SIZE; +} + +/* Given a pointer to an input file, read and parse that file +** as if it were SGML. +** +** This is not a true SGML parser because it handles some unusual +** cases differently, and ignores the & operator completely. +*/ +void SgmlParse(FILE *in, void *pArg){ + int c; + int i, j; + int argc; + Handler *pHandler; + char *argv[100]; + char zBuf[10000]; + + c = getc(in); + while( c!=EOF ){ + if( isspace(c) ){ + /* Case 1: spaces */ + zBuf[0] = c; + i = 1; + while( i<sizeof(zBuf)-2 && (c=getc(in))!=EOF && isspace(c) ){ + zBuf[i++] = c; + } + zBuf[i] = 0; + /* Dispose of space */ + if( xSpaceHandler ){ + (*xSpaceHandler)(zBuf,pArg); + } + }else if( c=='<' ){ + int cQuote = 0; + i = 0; + zBuf[i++] = c; + while( (c=getc(in))!=EOF && (cQuote || c!='>') ){ + if( i<sizeof(zBuf)-3 ) zBuf[i++] = c; + if( cQuote ){ + if( cQuote==c ) cQuote = 0; + }else if( c=='"' || c=='\'' ){ + cQuote = c; + } + } + if( c=='>' ) c = getc(in); + zBuf[i] = 0; + if( strncmp(zBuf,"<!--",4)==0 ){ + zBuf[i++] = '>'; + zBuf[i] = 0; + if( xCommentHandler ){ + (*xCommentHandler)(zBuf,pArg); + } + continue; + } + argc = 0; + argv[0] = &zBuf[1]; + for(j=1; zBuf[j] && !isspace(zBuf[j]); j++){} + if( zBuf[j] ){ + zBuf[j++] = 0; + while( argc<(sizeof(argv)/sizeof(argv[0])) - 4 && zBuf[j] ){ + while( isspace(zBuf[j]) ) j++; + argv[++argc] = &zBuf[j]; + while( zBuf[j] && !isspace(zBuf[j]) && zBuf[j]!='=' ) j++; + if( zBuf[j]!='=' ){ + argv[argc+1] = argv[argc]; + argc++; + if( zBuf[j] ) zBuf[j++] = 0; + continue; + } + zBuf[j++] = 0; + if( zBuf[j]=='"' || zBuf[j]=='\'' ){ + cQuote = zBuf[j++]; + }else{ + cQuote = 0; + } + argv[++argc] = &zBuf[j]; + if( cQuote ){ + while( zBuf[j] && zBuf[j]!=cQuote ) j++; + }else{ + while( zBuf[j] && !isspace(zBuf[j]) ) j++; + } + if( zBuf[j] ) zBuf[j++] = 0; + } + } + argv[++argc] = 0; + /* Despose of a markup */ + pHandler = apHandler[SgmlHash(argv[0])]; + while( pHandler && stricmp(pHandler->zName,argv[0])!=0 ){ + pHandler = pHandler->pCollide; + } + if( pHandler ){ + if( pHandler->xHandler ){ + (*pHandler->xHandler)(argc,(const char**)argv,pArg); + } + }else if( xDefaultMarkupHandler ){ + (*xDefaultMarkupHandler)(argc,(const char**)argv,pArg); + } + }else{ + zBuf[0] = c; + i = 1; + while( i<sizeof(zBuf)-2 && (c=getc(in))!=EOF && c!='<' && !isspace(c) ){ + zBuf[i++] = c; + } + zBuf[i] = 0; + /* Dispose of a word */ + if( xWordHandler ){ + (*xWordHandler)(zBuf,pArg); + } + } + } +} + +/* +** Clear out the handler hash table +*/ +void SgmlHandlerReset(void){ + Handler *pHandler; + int i; + + for(i=0; i<SGML_HASH_SIZE; i++){ + Handler *pNext; + for(pHandler=apHandler[i]; pHandler; pHandler=pNext){ + pNext = pHandler->pCollide; + free(pHandler); + } + apHandler[i] = 0; + } +} + +/* Install a new handler +*/ +void SgmlHandler(const char *zName, void (*xFunc)(int,const char**,void*)){ + int h = SgmlHash(zName); + extern void *malloc(); + Handler *pNew = malloc( sizeof(Handler) + strlen(zName) + 1 ); + if( pNew==0 ) return; + pNew->zName = (char*)&pNew[1]; + strcpy(pNew->zName,zName); + pNew->pCollide = apHandler[h]; + pNew->xHandler = xFunc; + apHandler[h] = pNew; +} + +/* Install the default handlers +*/ +void SgmlWordHandler(void (*xWord)(const char*,void*)){ + xWordHandler = xWord; +} +void SgmlSpaceHandler(void (*xSpace)(const char*,void*)){ + xSpaceHandler = xSpace; +} +void SgmlCommentHandler(void (*xComment)(const char*,void*)){ + xCommentHandler = xComment; +} +void SgmlDefaultMarkupHandler(void (*xMarkup)(int,const char**,void*)){ + xDefaultMarkupHandler = xMarkup; +} |