--- parser3/src/classes/op.C 2001/12/07 15:24:46 1.63 +++ parser3/src/classes/op.C 2002/06/20 14:50:22 1.97 @@ -1,18 +1,18 @@ /** @file Parser: parser @b operators. - Copyright (c) 2001 ArtLebedev Group (http://www.artlebedev.com) - Author: Alexander Petrosyan (http://paf.design.ru) + Copyright (c) 2001, 2002 ArtLebedev Group (http://www.artlebedev.com) + Author: Alexandr Petrosian (http://paf.design.ru) - $Id: op.C,v 1.63 2001/12/07 15:24:46 paf Exp $ + $Id: op.C,v 1.97 2002/06/20 14:50:22 paf Exp $ */ #include "classes.h" -#include "pa_config_includes.h" #include "pa_common.h" #include "pa_request.h" #include "pa_vint.h" #include "pa_sql_connection.h" +#include "pa_vdate.h" // limits @@ -20,7 +20,7 @@ // defines -#define OP_CLASS_NAME "OP" +#define CASE_DEFAULT_VALUE "DEFAULT" // class @@ -41,8 +41,8 @@ private: static void _if(Request& r, const String&, MethodParams *params) { Value& condition_code=params->as_junction(0, "condition must be expression"); - bool condition=r.process(condition_code, - 0/*no name*/, + bool condition=r.process_to_value(condition_code, + /*0/*no name* /,*/ false/*don't intercept string*/).as_bool(); if(condition) r.write_pass_lang(r.process(params->as_junction(1, "'then' parameter must be code"))); @@ -60,7 +60,7 @@ static void _untaint(Request& r, const S const String& lang_name=params->as_string(0, "lang must be string"); lang=untaint_lang_name2enum->get_int(lang_name); if(!lang) - throw Exception(0, 0, + throw Exception(0, &lang_name, "invalid taint language"); } @@ -83,7 +83,7 @@ static void _taint(Request& r, const Str const String& lang_name=params->as_string(0, "lang must be string"); lang=untaint_lang_name2enum->get_int(lang_name); if(!lang) - throw Exception(0, 0, + throw Exception(0, &lang_name, "invalid taint language"); } @@ -91,7 +91,7 @@ static void _taint(Request& r, const Str { Value& vbody=params->as_no_junction(params->size()-1, "body must not be code"); - String result(r.pool()); + String& result=*new(pool) String(pool); result.append( vbody.as_string(), // process marking tainted with that lang lang, true); // force result language to specified @@ -100,38 +100,52 @@ static void _taint(Request& r, const Str } static void _process(Request& r, const String& method_name, MethodParams *params) { + Pool& pool=r.pool(); // calculate pseudo file name of processed chars // would be something like "/some/file(4) process" - char place[MAX_STRING]; + char local_place[MAX_STRING]; #ifndef NO_STRING_ORIGIN const Origin& origin=method_name.origin(); - snprintf(place, MAX_STRING, "%s(%d) %s", - origin.file, 1+origin.line, - method_name.cstr()); + size_t place_size=snprintf(local_place, MAX_STRING, "%s(%d) %s", + origin.file?origin.file:"unknown_file", 1+origin.line, + method_name.cstr())+1; #else - strncpy(place, method_name.cstr(), MAX_STRING-1); place[MAX_STRING-1]=0; -#endif + strncpy(local_place, method_name.cstr(), MAX_STRING-1); place[MAX_STRING-1]=0; + size_t place_size=strlen(local_place)+1; +#endif + char *heap_place=(char *)r.malloc(place_size); + memcpy(heap_place, local_place, place_size); + VStateless_class& self_class=*r.self->get_class(); + const Method *main_method; { + // temporary remove language change + Temp_lang temp_lang(r, String::UL_PASS_APPENDED); // temporary zero @main so to maybe-replace it in processed code - Temp_method temp_method_main(self_class, *main_method_name, 0); + Temp_method temp_method_main(self_class, r.main_method_name, 0); // temporary zero @auto so it wouldn't be auto-called in Request::use_buf Temp_method temp_method_auto(self_class, *auto_method_name, 0); // evaluate source to process - const String& source= - r.process(params->as_junction(0, "body must be code")).as_string(); + const String& source=r.process_to_string(params->as_junction(0, "body must be code")); // process source code, append processed methods to 'self' class // maybe-define new @main - r.use_buf(source.cstr(String::UL_UNSPECIFIED, r.connection), place, &self_class); + r.use_buf( + source.cstr(String::UL_UNSPECIFIED, r.connection(0)), + *new(pool) String(pool, heap_place, place_size, true /*tainted*/), + heap_place, + &self_class); - // maybe-execute @main[] - if(const Method *method=self_class.get_method(*main_method_name)) { - // execute! - r.execute(*method->parser_code); - } + // main_method + main_method=self_class.get_method(r.main_method_name); + } + // after restoring current-request-lang + // maybe-execute @main[] + if(main_method) { + // execute! + r.execute(*main_method->parser_code); } } @@ -149,14 +163,12 @@ static void _while(Request& r, const Str int endless_loop_count=0; while(true) { if(++endless_loop_count>=MAX_LOOPS) // endless loop? - throw Exception(0, 0, + throw Exception("parser.runtime", &method_name, "endless loop detected"); - bool condition= - r.process( - vcondition, - 0/*no name*/, + bool condition=r.process_to_value(vcondition, + /*0/*no name* /,*/ false/*don't intercept string*/).as_bool(); if(!condition) // ...condition is true break; @@ -180,17 +192,17 @@ static void _for(Request& r, const Strin Value *delim_maybe_code=params->size()>4?¶ms->get(4):0; if(to-from>=MAX_LOOPS) // too long loop? - throw Exception(0, 0, + throw Exception("parser.runtime", &method_name, "endless loop detected"); bool need_delim=false; VInt *vint=new(pool) VInt(pool, 0); + r.root->put_element(var_name, vint); for(int i=from; i<=to; i++) { vint->set_int(i); - r.root->put_element(var_name, vint); - Value& processed_body=r.process(body_code); + StringOrValue processed_body=r.process(body_code); if(delim_maybe_code) { // delimiter set? const String *string=processed_body.get_string(); if(need_delim && string && string->size()) // need delim & iteration produced string? @@ -204,32 +216,20 @@ static void _for(Request& r, const Strin static void _eval(Request& r, const String& method_name, MethodParams *params) { Value& expr=params->as_junction(0, "need expression"); // evaluate expresion - Value *result=r.process(expr, - 0/*no name YET*/, + Value *value_result=r.process_to_value(expr, + /*0/*no name YET* /,*/ true/*don't intercept string*/).as_expr_result(); if(params->size()>1) { Value& fmt=params->as_no_junction(1, "fmt must not be code"); Pool& pool=r.pool(); String& string=*new(pool) String(pool); - string.APPEND_CONST(format(pool, result->as_double(), fmt.as_string().cstr())); - result=new(pool) VString(string); - } - result->set_name(method_name); - r.write_no_lang(*result); + string.APPEND_CONST(format(pool, value_result->as_double(), fmt.as_string().cstr())); + r.write_no_lang(string); + } else + r.write_no_lang(*value_result); } -static void _error(Request& r, const String& method_name, MethodParams *params) { - Pool& pool=r.pool(); - - const String& serror=params->as_string(0, "message must be string"); - throw Exception(0, 0, - &method_name, - "%s", serror.cstr()); -} - - -/// @todo rewrite ugly code with try/try to autoobject TempConnection static void _connect(Request& r, const String& method_name, MethodParams *params) { Pool& pool=r.pool(); #ifdef RESOURCES_DEBUG @@ -246,7 +246,7 @@ struct timeval mt[2]; gettimeofday(&mt[0],NULL); #endif // connect - SQL_Connection& connection=SQL_driver_manager->get_connection( + SQL_Connection_ptr connection=SQL_driver_manager->get_connection( url.as_string(), method_name, protocol2driver_and_client); #ifdef RESOURCES_DEBUG @@ -259,55 +259,37 @@ for(int i=0;i<2;i++) r.sql_connect_time+=t[1]-t[0]; #endif - // remember/set current connection - SQL_Connection *saved_connection=r.connection; - r.connection=&connection; + Temp_connection temp_connection(r, connection.get()); // execute body try { - try { - r.write_assign_lang(r.process(body_code)); - - connection.commit(); - } catch(...) { // process/commit problem - connection.rollback(); - - /*re*/throw; - } - - } catch(...) { - // close connection [cache it] - connection.close(); - // recall current connection from remembered - r.connection=saved_connection; - - /*re*/throw; + r.write_assign_lang(r.process(body_code)); + } catch(...) { // process problem + connection->mark_to_rollback(); + /*re*/throw; } - - // and anyway - // close connection [cache it] - connection.close(); - // recall current connection from remembered - r.connection=saved_connection; } #ifndef DOXYGEN struct Switch_data { + Request *r; Value *searching; Value *found; Value *_default; }; #endif static void _switch(Request& r, const String&, MethodParams *params) { - void *backup=r.classes_conf.get(*switch_data_name); - Switch_data data={&r.process(params->get(0))}; - r.classes_conf.put(*switch_data_name, &data); - - r.process(params->as_junction(1, "switch cases must be code")); // and ignore result - - r.classes_conf.put(*switch_data_name, backup); + Switch_data data={&r, &r.process_to_value(params->get(0))}; + Temp_hash_value switch_data_setter(r.classes_conf, *switch_data_name, &data); - if(Value *code=data.found ? data.found : data._default) - r.write_pass_lang(r.process(*code)); + Value& cases_code=params->as_junction(1, "switch cases must be code"); + // execution of found ^case[...]{code} must be in context of ^switch[...]{code} + // because of stacked WWrapper used there as wcontext + r.process(cases_code, true/*intercept_string*/); + if(Value *selected_code=data.found ? data.found : data._default) { + // setting code context, would execute in ^switch[...]{>>context<<} + selected_code->get_junction()->change_context(cases_code.get_junction()); + r.write_pass_lang(r.process(*selected_code)); + } } static void _case(Request& r, const String& method_name, MethodParams *params) { @@ -315,16 +297,21 @@ static void _case(Request& r, const Stri Switch_data *data=static_cast(r.classes_conf.get(*switch_data_name)); if(!data) - throw Exception(0, 0, + throw Exception("parser.runtime", &method_name, "without switch"); int count=params->size(); Value *code=¶ms->as_junction(--count, "case result must be code"); + + // killing context for safety, would execute in ^switch[...]{>>context<<} + // reason: context is stacked, and it would become invalid afterwards + code->get_junction()->change_context(0); + for(int i=0; iget(i)); + Value& value=r.process_to_value(params->get(i)); - if(value.as_string() == *case_default_value) { + if(value.as_string() == CASE_DEFAULT_VALUE) { data->_default=code; break; } @@ -336,6 +323,11 @@ static void _case(Request& r, const Stri matches=data->searching->as_double() == value.as_double(); if(matches) { + if(data->found) + throw Exception("parser.runtime", + &method_name, + "duplicate found"); + data->found=code; break; } @@ -346,110 +338,310 @@ static void _case(Request& r, const Stri // consts -const int DATA_STRING_SERIALIZED_VERSION=0x0001; +const int DATA_STRING_SERIALIZED_VERSION=0x0002; // helper types #ifndef DOXYGEN struct Data_string_serialized_prolog { int version; + time_t expires; }; #endif -void cache_delete(Pool& pool, const String& file_spec) { - file_delete(pool, file_spec, false/*fail_on_read_problem*/); +void cache_delete(const String& file_spec) { + file_delete(file_spec, false/*fail_on_read_problem*/); } -void cache_put(Pool& pool, const String& file_spec, const String& data_string) { - void *data; size_t data_size; - data_string.serialize( - sizeof(Data_string_serialized_prolog), - data, data_size); - Data_string_serialized_prolog& prolog= - *static_cast(data); - - prolog.version=DATA_STRING_SERIALIZED_VERSION; - - file_write(pool, - file_spec, - data, data_size, - false/*as_text*/); + +#ifndef DOXYGEN +struct Cache_data { + time_t expires; +}; +struct Locked_process_and_cache_put_action_info { + Request *r; + Cache_data *data; + Value *body_code; const String *evaluated_body; +}; +#endif +static void locked_process_and_cache_put_action(int f, void *context) { + Locked_process_and_cache_put_action_info& info= + *static_cast(context); + + // body->process + info.evaluated_body=&info.r->process_to_string(*info.body_code); + + // expiration time not spoiled by ^cache(0) or something? + if(info.data->expires > time(0)) { + // string -serialize> buffer + void *data; size_t data_size; + info.evaluated_body->serialize( + sizeof(Data_string_serialized_prolog), + data, data_size); + Data_string_serialized_prolog& prolog= + *static_cast(data); + prolog.version=DATA_STRING_SERIALIZED_VERSION; + prolog.expires=info.data->expires; + + // buffer -write> file + write(f, data, data_size); + } else // expired! + info.data->expires=0; // flag it so that could be easily checked by caller +} +const String *locked_process_and_cache_put(Request& r, + Value& body_code, + Cache_data& data, + const String& file_spec) { + Locked_process_and_cache_put_action_info info={ + &r, + &data, + &body_code + }; + + const String *result=file_write_action_under_lock( + file_spec, + "cache_put", locked_process_and_cache_put_action, &info, + false/*as_text*/, + false/*do_append*/, + false/*block*/, + false/*fail on lock problem*/) ? info.evaluated_body: 0; + if(data.expires==0) + cache_delete(file_spec); + return result; } -String *cache_get(Pool& pool, const String& file_spec) { +String *cache_get(Pool& pool, const String& file_spec, time_t now) { void* data; size_t data_size; - if(!file_read(pool, file_spec, + if(file_read(pool, file_spec, data, data_size, false/*as_text*/, - false/*fail_on_read_problem*/)) - return 0; + false/*fail_on_read_problem*/) + && data_size/* ignore reads which are empty due to + non-unary open+lockEX conflict with lockSH */) { - Data_string_serialized_prolog& prolog= - *static_cast(data); + Data_string_serialized_prolog& prolog= + *static_cast(data); - if(data_size=sizeof(Data_string_serialized_prolog) + && prolog.version==DATA_STRING_SERIALIZED_VERSION + && prolog.expires > now + && result->deserialize( + sizeof(Data_string_serialized_prolog), data, data_size, file_spec.cstr())) + return result; + } + + return 0; +} +static time_t as_expires(Request& r, const String& method_name, MethodParams *params, + int index, time_t now) { + time_t result; + Value& vlifespan_or_expires=params->get(index); + if(strcmp(vlifespan_or_expires.type(), VDATE_TYPE)==0) + result=static_cast(vlifespan_or_expires).get_time(); + else + result=now+(time_t)params->as_double(index, "lifespan must be date or number", r); - return &result; + return result; +} +static const String as_file_spec(Request&r, MethodParams *params, int index) { + return r.absolute(params->as_string(index, "filespec must be string")); } static void _cache(Request& r, const String& method_name, MethodParams *params) { - // ^cache[file_spec](lifespan){code} time=0 no cache Pool& pool=r.pool(); + time_t now=time(0); + + // ^cache[filename] ^cache(seconds) ^cache[expires date] + if(params->size()==1) { + if(params->get(0).is_string()) { // filename? + cache_delete(as_file_spec(r, params, 0)); + return; + } + + // secods|expires date + Cache_data *data=static_cast(r.classes_conf.get(*cache_data_name)); + if(!data) + throw Exception("parser.runtime", + &method_name, + "expire-time reducing instruction without cache"); + + time_t expires=as_expires(r, method_name, params, 0, now); + if(expires < data->expires) + data->expires=expires; + + return; + } // file_spec, expires, body code - const String &file_spec=params->as_string(0, "key must be string"); - time_t lifespan=(time_t)params->as_double(1, "lifespan must be number", r); + const String &file_spec=r.absolute(params->as_string(0, "filespec must be string")); + + Cache_data data; + Temp_hash_value cache_data_setter(r.classes_conf, *cache_data_name, &data); + data.expires=as_expires(r, method_name, params, 1, now); Value& body_code=params->as_junction(2, "body must be code"); - if(lifespan) { // 'lifespan' specified? try cached copy... - size_t size; - time_t atime, mtime, ctime; - // {file_spec} modification time - if(!file_stat(file_spec, size, atime, mtime, ctime, false/*no exception on error*/) - || (time(0)-mtime) > lifespan) // cached file expired - cache_delete(pool, file_spec); - else - if(String *cached_body=cache_get(pool, file_spec)) { // have cached copy? + if(data.expires>now) { // valid 'expires' specified? try cached copy... + // hence we don't hope to have unary create/lockEX + // we need some plan to live in a life like that, so... + // worst races plan: + // A B + // open + // |open + // lockSH + // |nonblocking-lockEX fails + // unlockSH + // close, cache_get returns 0 + // open + // nonblocking-lockEX succeeds; process, write, close + // |retry1: open + // ... + // |lockSH succeeds; ... + + for(int retry=0; retry<2; retry++) { + if(String *cached_body=cache_get(pool, file_spec, now)) { // have cached copy? // write it out r.write_assign_lang(*cached_body); // happy with it return; } - } else // 'lifespan'=0, forget cached copy - cache_delete(pool, file_spec); - - // process - Value& processed_body=r.process(body_code); - - // put it to cache if 'lifespan' specified - if(lifespan) - cache_put(pool, file_spec, processed_body.as_string()); + // non-blocked lock; process; cache it + if(const String*processed_body= + locked_process_and_cache_put(r, body_code, data, file_spec)) { + // write it out + r.write_assign_lang(*processed_body); + // happy with it + return; + } else { // somebody writing result right now + pa_sleep(0, 500000); // waiting half a second + retry=0; // prolonging our wait, than could cache_get it, without processing body_code + } + } + throw Exception(0, + &file_spec, + "locking problem"); + } else { + // instructed not to cache; forget cached copy + cache_delete(file_spec); + // process + const String& processed_body=r.process_to_string(body_code); + // write it out + r.write_assign_lang(processed_body); + // happy with it + return; + } + // never reached +} + +// also used in pa_request.C to pass param to @unhandled_exception +VHash& exception2vhash(Pool& pool, const Exception& e) { + VHash& result=*new(pool) VHash(pool); + Hash& hash=result.hash(0); + if(const char *type=e.type(true)) + hash.put(*exception_type_part_name, new(pool) VString(*new(pool) String(pool, type))); + if(const String *asource=e.problem_source()) { + String& source=*new(pool) String(pool); + source.append(*asource, String::UL_TAINTED, true/*forced*/); + + hash.put(*exception_source_part_name, new(pool) VString(source)); +#ifndef NO_STRING_ORIGIN + const Origin& origin=source.origin(); + hash.put(*new(pool) String(pool, "file", 0, true), + new(pool) VString(*new(pool) String(pool, origin.file))); + hash.put(*new(pool) String(pool, "lineno"), + new(pool) VInt(pool, 1+origin.line)); +#endif + } + if(const char *ecomment=e.comment(true)) { + int comment_size=strlen(ecomment); + char *pcomment=(char *)pool.malloc(comment_size); + memcpy(pcomment, ecomment, comment_size); + hash.put(*exception_comment_part_name, + new(pool) VString(*new(pool) String(pool, pcomment, comment_size, true/*tainted*/))); + } + hash.put(*exception_handled_part_name, + new(pool) VBool(pool, false)); + + return result; +} + +static void _try_operator(Request& r, const String& method_name, MethodParams *params) { + Pool& pool=r.pool(); + + Value& body_code=params->as_junction(0, "body_code must be code"); + Value& catch_code=params->as_junction(1, "catch_code must be code"); + + StringOrValue result; + + // taking snapshot of request processing status + //int ssexception_trace=r.exception_trace.top_index(); + int sstack=r.stack.top_index(); + Value *sself=r.self, *sroot=r.root, *srcontext=r.rcontext; + WContext *swcontext=r.wcontext; + try { + result=r.process(body_code); + } catch(const Exception& e) { + // restoring request processing status + //r.exception_trace.top_index(ssexception_trace); + r.stack.top_index(sstack); + r.self=sself; r.root=sroot, r.rcontext=srcontext; r.wcontext=swcontext; + + + VHash& vhash=exception2vhash(pool, e); + + Junction *junction=catch_code.get_junction(); + Value *saved_exception_var_value=junction->root->get_element(*exception_var_name); + junction->root->put_element(*exception_var_name, &vhash); + result=r.process(catch_code); + bool handled=false; + if(Value *value=static_cast(vhash.hash(0).get(*exception_handled_part_name))) + handled=value->as_bool(); + junction->root->put_element(*exception_var_name, saved_exception_var_value); + + if(!handled) + throw(e); // rethrow + } // write it out - r.write_assign_lang(processed_body); + r.write_pass_lang(result); } +static void _throw_operator(Request& r, const String& method_name, MethodParams *params) { + Pool& pool=r.pool(); + + if(params->size()==1) { + Value& param0=params->get(0); + if(Hash *hash=param0.get_hash(&method_name)) { + const char *type=0; + if(Value *value=static_cast(hash->get(*exception_type_part_name))) + type=value->as_string().cstr(); + const String *source=0; + if(Value *value=static_cast(hash->get(*exception_source_part_name))) + source=&value->as_string(); + const char *comment=0; + if(Value *value= + static_cast(hash->get(*exception_comment_part_name))) + comment=value->as_string().cstr(); + + throw Exception(type, + source?source:&method_name, + comment); + } else + throw Exception("parser.runtime", + &method_name, + "one-param version has hash param"); + } else { + const char *type=params->as_string(0, "type must be string").cstr(); + const String& source=params->as_string(1, "source must be string"); + const char *comment=params->size()>2?params->as_string(2, "comment must be string").cstr():0; + throw Exception(type, &source, "%s", comment?comment:""); + } +} + // constructor -MOP::MOP(Pool& apool) : Methoded(apool), +MOP::MOP(Pool& apool) : Methoded(apool, "OP"), main_sql_name(apool, MAIN_SQL_NAME), main_sql_drivers_name(apool, MAIN_SQL_DRIVERS_NAME) { - set_name(*NEW String(pool(), OP_CLASS_NAME)); - // ^if(condition){code-when-true} // ^if(condition){code-when-true}{code-when-false} add_native_method("if", Method::CT_ANY, _if, 2, 3); @@ -479,16 +671,13 @@ MOP::MOP(Pool& apool) : Methoded(apool), // ^eval(expr)[format] add_native_method("eval", Method::CT_ANY, _eval, 1, 2); - // ^error[msg] - add_native_method("error", Method::CT_ANY, _error, 1, 1); - - // ^connect[protocol://user:pass@host[:port]/database]{code with ^sql-s} add_native_method("connect", Method::CT_ANY, _connect, 2, 2); + // ^cache[file_spec] delete cache // ^cache[file_spec](time){code} time=0 no cache - add_native_method("cache", Method::CT_ANY, _cache, 3, 3); + add_native_method("cache", Method::CT_ANY, _cache, 1, 3); // switch @@ -497,6 +686,15 @@ MOP::MOP(Pool& apool) : Methoded(apool), // ^case[value]{code} add_native_method("case", Method::CT_ANY, _case, 2, 10000); + + // try-catch + + // ^try{code}{catch code} + add_native_method("try", Method::CT_ANY, _try_operator, 2, 2); + // ^throw[$exception hash] + // ^throw[type;source;comment] + add_native_method("throw", Method::CT_ANY, _throw_operator, 1, 3); + } // constructor & configurator