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#include <stdint.h>
#include <string.h>
#include "entities.h"
#include "fmt.h"
#include "textcode.h"
#include "haveinline.h"
#include "scan.h"
#include "case.h"
#include "str.h"
static const char* lookup(size_t ofs,const char* t) {
if (ofs>entities.tab[0]) return 0;
while (ofs<entities.tab[0]) {
unsigned char ch=entities.tab[ofs]&0xff;
if (ch==(unsigned char)*t || (!ch && *t==';')) {
if (!ch || *t==';')
return entities.data+(entities.tab[ofs]>>8);
else
return lookup(entities.tab[ofs]>>8,t+1);
} else
++ofs;
if (!ch) break;
}
return NULL;
}
enum htmlmode { /* <a href="http://example.com/"foo">libowfat<home</a> */
OUTSIDE, /* ^^^^^^^^^^^^^^^^ -> libowfat<home */
TAGARG, /* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -> http://example.com/"foo */
};
static size_t scan_html_inner(const char *src,char *dest,size_t *destlen,enum htmlmode mode) {
register const unsigned char* s=(const unsigned char*) src;
size_t written=0,i;
int dq=0;
for (i=0; s[i]; ++i) {
if (s[i]=='&') {
const char* utf8;
if (s[i+1]=='#') {
unsigned long l;
size_t j;
if ((s[i+2]&~32)=='X') {
j=scan_xlong(src+i+3,&l);
if (j) j+=3;
} else {
j=scan_ulong(src+i+2,&l);
if (j) j+=2;
}
if (s[i+j]==';') {
i+=j;
written+=fmt_utf8(dest?dest+written:0,l);
} else {
if (dest) dest[written]='&';
++written;
}
continue;
}
utf8=lookup(1,src+i+1);
if (utf8) {
size_t l=strlen(utf8);
if (dest) memcpy(dest+written,utf8,l);
written+=l;
i+=2+str_chr(src+i+2,';');
continue;
} else
if (dest) dest[written]='&';
} else if (s[i]=='<') {
break;
} else if (s[i]=='"' && mode==TAGARG) {
if (i==0) { dq=1; continue; }
break;
} else if (mode==TAGARG && !dq && (s[i]==' ' || s[i]=='\t' || s[i]=='\n'))
break;
else
if (dest) dest[written]=s[i];
++written;
}
if (destlen) *destlen=written;
return i;
}
size_t scan_html_tagarg(const char *src,char *dest,size_t *destlen) {
return scan_html_inner(src,dest,destlen,TAGARG);
}
size_t scan_html(const char *src,char *dest,size_t *destlen) {
return scan_html_inner(src,dest,destlen,OUTSIDE);
}
#ifdef UNITTEST
#include <assert.h>
#undef UNITTEST
#include <scan/scan_fromhex.c>
#include <scan/scan_xlongn.c>
#include <scan/scan_xlong.c>
#include <scan/scan_ulongn.c>
#include <scan/scan_ulong.c>
#include <str/str_chr.c>
#include <fmt/fmt_utf8.c>
#include <stdio.h>
int main() {
char* html="<a href=\"http://example.com/"foo\">libowfat<home</a>";
char buf[100];
size_t destlen;
/* check that we stop at < */
assert(scan_html(html,buf,&destlen)==0 && destlen==0);
/* check that we properly decode < */
memset(buf,'?',sizeof(buf));
assert(scan_html(strchr(html,'>')+1,buf,&destlen)==16 && destlen==13 && !memcmp(buf,"libowfat<home?",14));
/* check that we stop at " and properly decode " */
memset(buf,'?',sizeof(buf));
assert(scan_html_tagarg(strchr(html,'"')+1,buf,&destlen)==28 && destlen==23 && !memcmp(buf,"http://example.com/\"foo?",24));
/* check that we pass through invalid escapes */
memset(buf,'?',sizeof(buf));
assert(scan_html("&fnord;",buf,&destlen)==7 && destlen==7 && !memcmp(buf,"&fnord;?",8));
memset(buf,'?',sizeof(buf));
assert(scan_html("&#x;",buf,&destlen)==4 && destlen==4 && !memcmp(buf,"&#x;?",5));
memset(buf,'?',sizeof(buf));
assert(scan_html("&#;",buf,&destlen)==3 && destlen==3 && !memcmp(buf,"&#;?",4));
/* check that &#x[hex]; is decoded properly */
memset(buf,'?',sizeof(buf));
assert(scan_html("",buf,&destlen)==5 && destlen==1 && buf[0]==1 && buf[1]=='?');
/* check that &#[decimal]; is decoded properly */
memset(buf,'?',sizeof(buf));
assert(scan_html("",buf,&destlen)==4 && destlen==1 && buf[0]==1 && buf[1]=='?');
}
#endif
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