discovery: stop parser with XML_StopParser()

Signed-off-by: Michael Krelin <hacker@klever.net>

2 files changed, 16 insertions, 8 deletions

diff --git a/include/opkele/expat.h b/include/opkele/expat.h
index 60c41ac..97ed61a 100644
--- a/include/opkele/expat.h
+++ b/include/opkele/expat.h
@@ -1,91 +1,93 @@
 #ifndef __OPKELE_EXPAT_H
 #define __OPKELE_EXPAT_H
 
 #include <cassert>
 #include <expat.h>
 
 namespace opkele {
 
     namespace util {
 
 	class expat_t {
 	    public:
 		XML_Parser _x;
 
 		expat_t() : _x(0) { }
 		expat_t(XML_Parser x) : _x(x) { }
 		virtual ~expat_t() throw();
 
 		expat_t& operator=(XML_Parser x);
 
 		operator const XML_Parser(void) const { return _x; }
 		operator XML_Parser(void) { return _x; }
 
 		inline bool parse(const char *s,int len,bool final=false) {
 		    assert(_x);
-		    return XML_Parse(_x,s,len,final);
-		}
+		    return XML_Parse(_x,s,len,final); }
+		enum XML_Status stop_parser(bool resumable=false) {
+		    assert(_x);
+		    return XML_StopParser(_x,resumable); }
 
 		virtual void start_element(const XML_Char *n,const XML_Char **a) { }
 		virtual void end_element(const XML_Char *n) { }
 		void set_element_handler();
 
 		virtual void character_data(const XML_Char *s,int l) { }
 		void set_character_data_handler();
 
 		virtual void processing_instruction(const XML_Char *t,const XML_Char *d) { }
 		void set_processing_instruction_handler();
 
 		virtual void comment(const XML_Char *d) { }
 		void set_comment_handler();
 
 		virtual void start_cdata_section() { }
 		virtual void end_cdata_section() { }
 		void set_cdata_section_handler();
 
 		virtual void default_handler(const XML_Char *s,int l) { }
 		void set_default_handler();
 		void set_default_handler_expand();
 
 		virtual void start_namespace_decl(const XML_Char *p,const XML_Char *u) { }
 		virtual void end_namespace_decl(const XML_Char *p) { }
 		void set_namespace_decl_handler();
 
 		inline enum XML_Error get_error_code() {
 		    assert(_x); return XML_GetErrorCode(_x); }
 		static inline const XML_LChar *error_string(XML_Error c) {
 		    return XML_ErrorString(c); }
 
 		inline long get_current_byte_index() {
 		    assert(_x); return XML_GetCurrentByteIndex(_x); }
 		inline int get_current_line_number() {
 		    assert(_x); return XML_GetCurrentLineNumber(_x); }
 		inline int get_current_column_number() {
 		    assert(_x); return XML_GetCurrentColumnNumber(_x); }
 
 		inline void set_user_data() {
 		    assert(_x); XML_SetUserData(_x,this); }
 
 		inline bool set_base(const XML_Char *b) {
 		    assert(_x); return XML_SetBase(_x,b); }
 		inline const XML_Char *get_base() {
 		    assert(_x); return XML_GetBase(_x); }
 
 		inline int get_specified_attribute_count() {
 		    assert(_x); return XML_GetSpecifiedAttributeCount(_x); }
 
 		inline bool set_param_entity_parsing(enum XML_ParamEntityParsing c) {
 		    assert(_x); return XML_SetParamEntityParsing(_x,c); }
 
 		inline static XML_Parser parser_create(const XML_Char *e=0) {
 		    return XML_ParserCreate(e); }
 		inline static XML_Parser parser_create_ns(const XML_Char *e=0,XML_Char s='\t') {
 		    return XML_ParserCreateNS(e,s); }
 
 	};
 
     }
 
 }
 
 #endif /* __OPKELE_EXPAT_H */
diff --git a/lib/discovery.cc b/lib/discovery.cc
index 81727c0..8729cfb 100644
--- a/lib/discovery.cc
+++ b/lib/discovery.cc
@@ -1,388 +1,394 @@
 #include <list>
 #include <opkele/curl.h>
 #include <opkele/expat.h>
 #include <opkele/uris.h>
 #include <opkele/discovery.h>
 #include <opkele/exception.h>
 #include <opkele/util.h>
+#include <opkele/debug.h>
 
 #include "config.h"
 
 #define XRDS_HEADER "X-XRDS-Location"
 #define CT_HEADER "Content-Type"
 
 namespace opkele {
     using std::list;
     using xrd::XRD_t;
     using xrd::service_t;
 
     static const char *whitespace = " \t\r\n";
     static const char *i_leaders = "=@+$!(";
 
     static inline bool is_qelement(const XML_Char *n,const char *qen) {
 	return !strcasecmp(n,qen);
     }
     static inline bool is_element(const XML_Char *n,const char *en) {
 	if(!strcasecmp(n,en)) return true;
 	int nl = strlen(n), enl = strlen(en);
 	if( (nl>=(enl+1)) && n[nl-enl-1]=='\t'
 		&& !strcasecmp(&n[nl-enl],en) )
 	    return true;
 	return false;
     }
 
     static long element_priority(const XML_Char **a) {
 	for(;*a;++a)
 	    if(!strcasecmp(*(a++),"priority")) {
 		long rv;
 		return (sscanf(*a,"%ld",&rv)==1)?rv:-1;
 	    }
 	return -1;
     }
 
     class idigger_t : public util::curl_t, public util::expat_t {
 	public:
 	    string xri_proxy;
 
 	    enum {
 		xmode_html = 1, xmode_xrd = 2
 	    };
 	    int xmode;
 
 	    string xrds_location;
 	    string http_content_type;
 	    service_t html_openid1;
 	    service_t html_openid2;
 	    string cdata_buf;
 	    long status_code;
 	    string status_string;
 
 	    typedef list<string> pt_stack_t;
 	    pt_stack_t pt_stack;
 	    int skipping;
 
 	    XRD_t *xrd;
 	    service_t *xrd_service;
 	    string* cdata;
 
 	    idigger_t()
 		: util::curl_t(easy_init()),
 		util::expat_t(0),
 		xri_proxy(XRI_PROXY_URL) {
 		    CURLcode r;
 		    (r=misc_sets())
 			|| (r=set_write())
 			|| (r=set_header())
 			;
 		    if(r)
 			throw exception_curl(OPKELE_CP_ "failed to set curly options",r);
 		}
 	    ~idigger_t() throw() { }
 
 	    void discover(idiscovery_t& result,const string& identity) {
 		result.clear();
 		string::size_type fsc = identity.find_first_not_of(whitespace);
 		if(fsc==string::npos)
 		    throw bad_input(OPKELE_CP_ "whtiespace-only identity");
 		string::size_type lsc = identity.find_last_not_of(whitespace);
 		assert(lsc!=string::npos);
 		if(!strncasecmp(identity.c_str()+fsc,"xri://",sizeof("xri://")-1))
 		    fsc += sizeof("xri://")-1;
 		if((fsc+1)>=lsc)
 		    throw bad_input(OPKELE_CP_ "not a character of importance in identity");
 		string id(identity,fsc,lsc-fsc+1);
 		if(strchr(i_leaders,id[0])) {
 		    result.normalized_id = id;
 		    result.xri_identity = true;
 		    /* TODO: further canonicalize xri identity? Like folding case  or whatever... */
 		    discover_at(
 			    result,
 			    xri_proxy + util::url_encode(id)+
 			    "?_xrd_r=application/xrd+xml;sep=false", xmode_xrd);
 		    if(status_code!=100)
 			throw failed_xri_resolution(OPKELE_CP_
 				"XRI resolution failed with '"+status_string+"' message",status_code);
 		    if(result.xrd.canonical_ids.empty())
 			throw opkele::failed_discovery(OPKELE_CP_ "No CanonicalID for XRI identity found");
 		    result.canonicalized_id = result.xrd.canonical_ids.begin()->second;
 		}else{
 		    result.xri_identity = false;
 		    if(id.find("://")==string::npos)
 			id.insert(0,"http://");
 		    string::size_type fp = id.find('#');
 		    if(fp!=string::npos) {
 			string::size_type qp = id.find('?');
 			if(qp==string::npos || qp<fp)
 			    id.erase(fp);
 			else if(qp>fp)
 			    id.erase(fp,qp-fp);
 		    }
 		    result.normalized_id = util::rfc_3986_normalize_uri(id);
 		    discover_at(result,id,xmode_html|xmode_xrd);
 		    const char * eu = 0;
 		    CURLcode r = easy_getinfo(CURLINFO_EFFECTIVE_URL,&eu);
 		    if(r)
 			throw exception_curl(OPKELE_CP_ "failed to get CURLINFO_EFFECTIVE_URL",r);
 		    result.canonicalized_id = util::rfc_3986_normalize_uri(eu); /* XXX: strip fragment part? */
 		    if(xrds_location.empty()) {
 			html2xrd(result.xrd);
 		    }else{
 			discover_at(result,xrds_location,xmode_xrd);
 			if(result.xrd.empty())
 			    html2xrd(result.xrd);
 		    }
 		}
 	    }
 
 	    void discover_at(idiscovery_t& result,const string& url,int xm) {
 		CURLcode r = easy_setopt(CURLOPT_URL,url.c_str());
 		if(r)
 		    throw exception_curl(OPKELE_CP_ "failed to set culry urlie",r);
 
 		(*(expat_t*)this) = parser_create_ns();
 		set_user_data(); set_element_handler();
 		set_character_data_handler();
 
 		http_content_type.clear();
 		xmode = xm;
 		if(xmode&xmode_html) {
 		    xrds_location.clear();
 		    html_openid1.clear(); html_openid2.clear();
 		}
 		xrd = &result.xrd;
 		cdata = 0; xrd_service = 0; skipping = 0;
 		status_code = 100; status_string.clear();
 
 		r = easy_perform();
 		if(r && r!=CURLE_WRITE_ERROR)
 		    throw exception_curl(OPKELE_CP_ "failed to perform curly request",r);
 
 		parse(0,0,true);
 	    }
 
 	    void html2xrd(XRD_t& x) {
 		if(!html_openid1.uris.empty()) {
 		    html_openid1.types.insert(STURI_OPENID11);
 		    x.services.add(-1,html_openid1);
 		}
 		if(!html_openid2.uris.empty()) {
 		    html_openid2.types.insert(STURI_OPENID20);
 		    x.services.add(-1,html_openid2);
 		}
 	    }
 
 	    size_t write(void *p,size_t s,size_t nm) {
 		if(skipping<0) return 0;
 		/* TODO: limit total size */
 		size_t bytes = s*nm;
-		parse((const char *)p,bytes,false);
+		bool rp = parse((const char *)p,bytes,false);
+		if(!rp) {
+		    skipping = -1;
+		    bytes = 0;
+		}
 		return bytes;
 	    }
 	    size_t header(void *p,size_t s,size_t nm) {
 		size_t bytes = s*nm;
 		const char *h = (const char*)p;
 		const char *colon = (const char*)memchr(p,':',bytes);
 		const char *space = (const char*)memchr(p,' ',bytes);
 		if(space && ( (!colon) || space<colon ) ) {
 		    xrds_location.clear(); http_content_type.clear();
 		}else if(colon) {
 		    const char *hv = ++colon;
 		    int hnl = colon-h;
 		    int rb;
 		    for(rb = bytes-hnl-1;rb>0 && isspace(*hv);++hv,--rb);
 		    while(rb>0 && isspace(hv[rb-1])) --rb;
 		    if(rb) {
 			if( (hnl>=sizeof(XRDS_HEADER))
 				&& !strncasecmp(h,XRDS_HEADER":",
 				    sizeof(XRDS_HEADER)) ) {
 			    xrds_location.assign(hv,rb);
 			}else if( (hnl>=sizeof(CT_HEADER))
 				&& !strncasecmp(h,CT_HEADER":",
 				    sizeof(CT_HEADER)) ) {
 			    const char *sc = (const char*)memchr(
 				    hv,';',rb);
 			    http_content_type.assign(hv,sc?(sc-hv):rb);
 			}
 		    }
 		}
 		return curl_t::header(p,s,nm);
 	    }
 
 	    void start_element(const XML_Char *n,const XML_Char **a) {
 		if(skipping<0) return;
 		if(skipping) {
 		    if(xmode&xmode_html)
 			html_start_element(n,a);
 		    ++skipping; return;
 		}
 		if(pt_stack.empty()) {
 		    if(is_qelement(n,NSURI_XRDS "\tXRDS"))
 			return;
 		    if(is_qelement(n,NSURI_XRD "\tXRD")) {
 			assert(xrd);
 			xrd->clear();
 			pt_stack.push_back(n);
 		    }else if(xmode&xmode_html) {
 			html_start_element(n,a);
 		    }else{
-			skipping = -1;
+			skipping = -1; stop_parser();
 		    }
 		}else{
 		    int pt_s = pt_stack.size();
 		    if(pt_s==1) {
 			if(is_qelement(n,NSURI_XRD "\tCanonicalID")) {
 			    assert(xrd);
 			    cdata = &(xrd->canonical_ids.add(element_priority(a),string()));
 			}else if(is_qelement(n,NSURI_XRD "\tLocalID")) {
 			    assert(xrd);
 			    cdata = &(xrd->local_ids.add(element_priority(a),string()));
 			}else if(is_qelement(n,NSURI_XRD "\tProviderID")) {
 			    assert(xrd);
 			    cdata = &(xrd->provider_id);
 			}else if(is_qelement(n,NSURI_XRD "\tService")) {
 			    assert(xrd);
 			    xrd_service = &(xrd->services.add(element_priority(a),
 					service_t()));
 			    pt_stack.push_back(n);
 			}else if(is_qelement(n,NSURI_XRD "\tStatus")) {
 			    for(;*a;) {
 				if(!strcasecmp(*(a++),"code")) {
 				    if(sscanf(*(a++),"%ld",&status_code)==1 && status_code!=100) {
 					cdata = &status_string;
 					pt_stack.push_back(n);
 					break;
 				    }
 				}
 			    }
 			}else if(is_qelement(n,NSURI_XRD "\tExpires")) {
 			    assert(xrd);
 			    cdata_buf.clear();
 			    cdata = &cdata_buf;
 			}else if(xmode&xmode_html) {
 			    html_start_element(n,a);
 			}else{
 			    skipping = 1;
 			}
 		    }else if(pt_s==2) {
 			if(is_qelement(pt_stack.back().c_str(), NSURI_XRD "\tService")) {
 			    if(is_qelement(n,NSURI_XRD "\tType")) {
 				assert(xrd); assert(xrd_service);
 				cdata_buf.clear();
 				cdata = &cdata_buf;
 			    }else if(is_qelement(n,NSURI_XRD "\tURI")) {
 				assert(xrd); assert(xrd_service);
 				cdata = &(xrd_service->uris.add(element_priority(a),string()));
 			    }else if(is_qelement(n,NSURI_XRD "\tLocalID")
 				    || is_qelement(n,NSURI_OPENID10 "\tDelegate") ) {
 				assert(xrd); assert(xrd_service);
 				cdata = &(xrd_service->local_ids.add(element_priority(a),string()));
 			    }else if(is_qelement(n,NSURI_XRD "\tProviderID")) {
 				    assert(xrd); assert(xrd_service);
 				    cdata = &(xrd_service->provider_id);
 			    }else{
 				skipping = 1;
 			    }
 			}else
 			    skipping = 1;
 		    }else if(xmode&xmode_html) {
 			html_start_element(n,a);
 		    }else{
 			skipping = 1;
 		    }
 		}
 	    }
 	    void end_element(const XML_Char *n) {
 		if(skipping<0) return;
 		if(skipping) {
 		    --skipping; return;
 		}
 		if(is_qelement(n,NSURI_XRD "\tType")) {
 		    assert(xrd); assert(xrd_service); assert(cdata==&cdata_buf);
 		    xrd_service->types.insert(cdata_buf);
 		}else if(is_qelement(n,NSURI_XRD "\tService")) {
 		    assert(xrd); assert(xrd_service);
 		    assert(!pt_stack.empty());
 		    assert(pt_stack.back()==(NSURI_XRD "\tService"));
 		    pt_stack.pop_back();
 		    xrd_service = 0;
 		}else if(is_qelement(n,NSURI_XRD "\tStatus")) {
 		    assert(xrd);
 		    if(is_qelement(pt_stack.back().c_str(),n)) {
 			assert(cdata==&status_string);
 			pt_stack.pop_back();
-			if(status_code!=100)
-			    skipping = -1;
+			if(status_code!=100) {
+			    skipping = -1; stop_parser();
+			}
 		    }
 		}else if(is_qelement(n,NSURI_XRD "\tExpires")) {
 		    assert(xrd);
 		    xrd->expires = util::w3c_to_time(cdata_buf);
 		}else if((xmode&xmode_html) && is_element(n,"head")) {
-		    skipping = -1;
+		    skipping = -1; stop_parser();
 		}
 		cdata = 0;
 	    }
 	    void character_data(const XML_Char *s,int l) {
 		if(skipping) return;
 		if(cdata) cdata->append(s,l);
 	    }
 
 	    void html_start_element(const XML_Char *n,const XML_Char **a) {
 		if(is_element(n,"meta")) {
 		    bool heq = false;
 		    string l;
 		    for(;*a;a+=2) {
 			if(!( strcasecmp(a[0],"http-equiv")
 				|| strcasecmp(a[1],XRDS_HEADER) ))
 			    heq = true;
 			else if(!strcasecmp(a[0],"content"))
 			    l.assign(a[1]);
 		    }
 		    if(heq)
 			xrds_location = l;
 		}else if(is_element(n,"link")) {
 		    string rels;
 		    string href;
 		    for(;*a;a+=2) {
 			if( !strcasecmp(a[0],"rel") ) {
 			    rels.assign(a[1]);
 			}else if( !strcasecmp(a[0],"href") ) {
 			    const char *ns = a[1];
 			    for(;*ns && isspace(*ns);++ns);
 			    href.assign(ns);
 			    string::size_type lns=href.find_last_not_of(whitespace);
 			    href.erase(lns+1);
 			}
 		    }
 		    for(string::size_type ns=rels.find_first_not_of(whitespace);
 			    ns!=string::npos; ns=rels.find_first_not_of(whitespace,ns)) {
 			string::size_type s = rels.find_first_of(whitespace,ns);
 			string rel;
 			if(s==string::npos) {
 			    rel.assign(rels,ns,string::npos);
 			    ns = string::npos;
 			}else{
 			    rel.assign(rels,ns,s-ns);
 			    ns = s;
 			}
 			if(rel=="openid.server")
 			    html_openid1.uris.add(-1,href);
 			else if(rel=="openid.delegate")
 			    html_openid1.local_ids.add(-1,href);
 			else if(rel=="openid2.provider")
 			    html_openid2.uris.add(-1,href);
 			else if(rel=="openid2.local_id")
 			    html_openid2.local_ids.add(-1,href);
 		    }
 		}else if(is_element(n,"body")) {
-		    skipping = -1;
+		    skipping = -1; stop_parser();
 		}
 	    }
 
     };
 
     void idiscover(idiscovery_t& result,const string& identity) {
 	idigger_t idigger;
 	idigger.discover(result,identity);
     }
 
 }