diff options
Diffstat (limited to 'src/regexp_vtab.cc')
| -rw-r--r-- | src/regexp_vtab.cc | 643 |
1 files changed, 643 insertions, 0 deletions
diff --git a/src/regexp_vtab.cc b/src/regexp_vtab.cc new file mode 100644 index 0000000..e3ed4fa --- /dev/null +++ b/src/regexp_vtab.cc @@ -0,0 +1,643 @@ +/** + * Copyright (c) 2017, Timothy Stack + * + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * * Redistributions of source code must retain the above copyright notice, this + * list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * * Neither the name of Timothy Stack nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ''AS IS'' AND ANY + * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED + * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY + * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND + * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#ifdef __CYGWIN__ +# include <alloca.h> +#endif + +#include "base/lnav_log.hh" +#include "column_namer.hh" +#include "config.h" +#include "lnav_util.hh" +#include "pcrepp/pcre2pp.hh" +#include "scn/scn.h" +#include "sql_help.hh" +#include "sql_util.hh" +#include "vtab_module.hh" +#include "yajlpp/yajlpp.hh" +#include "yajlpp/yajlpp_def.hh" + +enum { + RC_COL_MATCH_INDEX, + RC_COL_INDEX, + RC_COL_NAME, + RC_COL_CAPTURE_COUNT, + RC_COL_RANGE_START, + RC_COL_RANGE_STOP, + RC_COL_CONTENT, + RC_COL_VALUE, + RC_COL_PATTERN, +}; + +struct regexp_capture { + static constexpr const char* NAME = "regexp_capture"; + static constexpr const char* CREATE_STMT = R"( +-- The regexp_capture() table-valued function allows you to execute a regular- +-- expression over a given string and get the captured data as rows in a table. +CREATE TABLE regexp_capture ( + match_index INTEGER, + capture_index INTEGER, + capture_name TEXT, + capture_count INTEGER, + range_start INTEGER, + range_stop INTEGER, + content TEXT, + value TEXT HIDDEN, + pattern TEXT HIDDEN +); +)"; + + struct cursor { + sqlite3_vtab_cursor base; + std::shared_ptr<lnav::pcre2pp::code> c_pattern; + lnav::pcre2pp::match_data c_match_data{ + lnav::pcre2pp::match_data::unitialized()}; + std::string c_content; + string_fragment c_remaining; + bool c_content_as_blob{false}; + int c_index{0}; + bool c_matched{false}; + int c_match_index{0}; + sqlite3_int64 c_rowid{0}; + + cursor(sqlite3_vtab* vt) : base({vt}) {} + + int reset() { return SQLITE_OK; } + + int next() + { + if (this->c_index >= (this->c_match_data.get_count() - 1)) { + auto match_res = this->c_pattern->capture_from(this->c_content) + .at(this->c_remaining) + .into(this->c_match_data) + .matches(PCRE2_NO_UTF_CHECK) + .ignore_error(); + if (match_res) { + this->c_remaining = match_res->f_remaining; + } + this->c_matched = match_res.has_value(); + this->c_index = -1; + this->c_match_index += 1; + } + + if (!this->c_matched) { + return SQLITE_OK; + } + + this->c_index += 1; + + return SQLITE_OK; + } + + int eof() { return this->c_pattern == nullptr || !this->c_matched; } + + int get_rowid(sqlite3_int64& rowid_out) + { + rowid_out = this->c_rowid; + + return SQLITE_OK; + } + }; + + int get_column(const cursor& vc, sqlite3_context* ctx, int col) + { + const auto cap = vc.c_match_data[vc.c_index]; + + switch (col) { + case RC_COL_MATCH_INDEX: + sqlite3_result_int64(ctx, vc.c_match_index); + break; + case RC_COL_INDEX: + sqlite3_result_int64(ctx, vc.c_index); + break; + case RC_COL_NAME: + if (vc.c_index == 0) { + sqlite3_result_null(ctx); + } else { + to_sqlite(ctx, + vc.c_pattern->get_name_for_capture(vc.c_index)); + } + break; + case RC_COL_CAPTURE_COUNT: + sqlite3_result_int64(ctx, vc.c_match_data.get_count()); + break; + case RC_COL_RANGE_START: + if (cap.has_value()) { + sqlite3_result_int64(ctx, cap->sf_begin + 1); + } else { + sqlite3_result_int64(ctx, 0); + } + break; + case RC_COL_RANGE_STOP: + if (cap.has_value()) { + sqlite3_result_int64(ctx, cap->sf_end + 1); + } else { + sqlite3_result_int64(ctx, 0); + } + break; + case RC_COL_CONTENT: + if (cap.has_value()) { + to_sqlite(ctx, cap.value()); + } else { + sqlite3_result_null(ctx); + } + break; + case RC_COL_VALUE: + if (vc.c_content_as_blob) { + sqlite3_result_blob64(ctx, + vc.c_content.c_str(), + vc.c_content.length(), + SQLITE_STATIC); + } else { + sqlite3_result_text(ctx, + vc.c_content.c_str(), + vc.c_content.length(), + SQLITE_STATIC); + } + break; + case RC_COL_PATTERN: { + to_sqlite(ctx, vc.c_pattern->get_pattern()); + break; + } + } + + return SQLITE_OK; + } +}; + +static int +rcBestIndex(sqlite3_vtab* tab, sqlite3_index_info* pIdxInfo) +{ + vtab_index_constraints vic(pIdxInfo); + vtab_index_usage viu(pIdxInfo); + + for (auto iter = vic.begin(); iter != vic.end(); ++iter) { + if (iter->op != SQLITE_INDEX_CONSTRAINT_EQ) { + continue; + } + + switch (iter->iColumn) { + case RC_COL_VALUE: + case RC_COL_PATTERN: + viu.column_used(iter); + break; + } + } + + viu.allocate_args(RC_COL_VALUE, RC_COL_PATTERN, 2); + return SQLITE_OK; +} + +static int +rcFilter(sqlite3_vtab_cursor* pVtabCursor, + int idxNum, + const char* idxStr, + int argc, + sqlite3_value** argv) +{ + regexp_capture::cursor* pCur = (regexp_capture::cursor*) pVtabCursor; + + if (argc != 2) { + pCur->c_content.clear(); + pCur->c_pattern.reset(); + return SQLITE_OK; + } + + auto byte_count = sqlite3_value_bytes(argv[0]); + auto blob = (const char*) sqlite3_value_blob(argv[0]); + + pCur->c_content_as_blob = (sqlite3_value_type(argv[0]) == SQLITE_BLOB); + pCur->c_content.assign(blob, byte_count); + + auto pattern = from_sqlite<string_fragment>()(argc, argv, 1); + auto compile_res = lnav::pcre2pp::code::from(pattern); + if (compile_res.isErr()) { + pVtabCursor->pVtab->zErrMsg + = sqlite3_mprintf("Invalid regular expression: %s", + compile_res.unwrapErr().get_message().c_str()); + return SQLITE_ERROR; + } + + pCur->c_pattern = compile_res.unwrap().to_shared(); + + pCur->c_index = 0; + pCur->c_match_data = pCur->c_pattern->create_match_data(); + + pCur->c_remaining.clear(); + auto match_res = pCur->c_pattern->capture_from(pCur->c_content) + .into(pCur->c_match_data) + .matches(PCRE2_NO_UTF_CHECK) + .ignore_error(); + if (match_res) { + pCur->c_remaining = match_res->f_remaining; + } + pCur->c_matched = match_res.has_value(); + pCur->c_match_index = 0; + + return SQLITE_OK; +} + +enum { + RCJ_COL_MATCH_INDEX, + RCJ_COL_CONTENT, + RCJ_COL_VALUE, + RCJ_COL_PATTERN, + RCJ_COL_FLAGS, +}; + +struct regexp_capture_flags { + bool convert_numbers{true}; +}; + +const typed_json_path_container<regexp_capture_flags> + regexp_capture_flags_handlers + = typed_json_path_container<regexp_capture_flags>{ + yajlpp::property_handler("convert-numbers") + .for_field(®exp_capture_flags::convert_numbers), + }; + +struct regexp_capture_into_json { + static constexpr const char* NAME = "regexp_capture_into_json"; + static constexpr const char* CREATE_STMT = R"( +-- The regexp_capture_into_json() table-valued function allows you to execute a +-- regular-expression over a given string and get the captured data as rows in +-- a table. +CREATE TABLE regexp_capture_into_json ( + match_index INTEGER, + content TEXT, + value TEXT HIDDEN, + pattern TEXT HIDDEN, + flags TEXT HIDDEN +); +)"; + + struct cursor { + sqlite3_vtab_cursor base; + std::shared_ptr<lnav::pcre2pp::code> c_pattern; + lnav::pcre2pp::match_data c_match_data{ + lnav::pcre2pp::match_data::unitialized()}; + std::unique_ptr<column_namer> c_namer; + std::string c_content; + string_fragment c_remaining; + bool c_content_as_blob{false}; + bool c_matched{false}; + size_t c_match_index{0}; + sqlite3_int64 c_rowid{0}; + std::string c_flags_string; + nonstd::optional<regexp_capture_flags> c_flags; + + cursor(sqlite3_vtab* vt) : base({vt}) {} + + int reset() { return SQLITE_OK; } + + int next() + { + auto match_res = this->c_pattern->capture_from(this->c_content) + .at(this->c_remaining) + .into(this->c_match_data) + .matches(PCRE2_NO_UTF_CHECK) + .ignore_error(); + if (match_res) { + this->c_remaining = match_res->f_remaining; + } + this->c_matched = match_res.has_value(); + this->c_match_index += 1; + + if (!this->c_matched) { + return SQLITE_OK; + } + + return SQLITE_OK; + } + + int eof() { return this->c_pattern == nullptr || !this->c_matched; } + + int get_rowid(sqlite3_int64& rowid_out) + { + rowid_out = this->c_rowid; + + return SQLITE_OK; + } + }; + + int get_column(const cursor& vc, sqlite3_context* ctx, int col) + { + switch (col) { + case RCJ_COL_MATCH_INDEX: + sqlite3_result_int64(ctx, vc.c_match_index); + break; + case RCJ_COL_CONTENT: { + yajlpp_gen gen; + yajl_gen_config(gen, yajl_gen_beautify, false); + + { + yajlpp_map root_map(gen); + + for (int lpc = 1; lpc < vc.c_match_data.get_count(); lpc++) + { + const auto& colname = vc.c_namer->cn_names[lpc]; + const auto cap = vc.c_match_data[lpc]; + + if (!cap) { + continue; + } + + yajl_gen_pstring(gen, colname.data(), colname.length()); + + if (!vc.c_flags || vc.c_flags->convert_numbers) { + auto cap_view = cap->to_string_view(); + auto scan_int_res + = scn::scan_value<int64_t>(cap_view); + + if (scan_int_res && scan_int_res.range().empty()) { + yajl_gen_integer(gen, scan_int_res.value()); + continue; + } + + auto scan_float_res + = scn::scan_value<double>(cap_view); + if (scan_float_res + && scan_float_res.range().empty()) + { + yajl_gen_number( + gen, cap_view.data(), cap_view.length()); + continue; + } + + yajl_gen_pstring( + gen, cap_view.data(), cap_view.length()); + } else { + yajl_gen_pstring(gen, cap->data(), cap->length()); + } + } + } + + auto sf = gen.to_string_fragment(); + sqlite3_result_text( + ctx, sf.data(), sf.length(), SQLITE_TRANSIENT); + sqlite3_result_subtype(ctx, JSON_SUBTYPE); + break; + } + case RCJ_COL_VALUE: + if (vc.c_content_as_blob) { + sqlite3_result_blob64(ctx, + vc.c_content.c_str(), + vc.c_content.length(), + SQLITE_STATIC); + } else { + sqlite3_result_text(ctx, + vc.c_content.c_str(), + vc.c_content.length(), + SQLITE_STATIC); + } + break; + case RCJ_COL_PATTERN: { + to_sqlite(ctx, vc.c_pattern->get_pattern()); + break; + } + case RCJ_COL_FLAGS: { + if (!vc.c_flags) { + sqlite3_result_null(ctx); + } else { + to_sqlite(ctx, vc.c_flags_string); + } + break; + } + } + + return SQLITE_OK; + } +}; + +static int +rcjBestIndex(sqlite3_vtab* tab, sqlite3_index_info* pIdxInfo) +{ + vtab_index_constraints vic(pIdxInfo); + vtab_index_usage viu(pIdxInfo); + + for (auto iter = vic.begin(); iter != vic.end(); ++iter) { + if (iter->op != SQLITE_INDEX_CONSTRAINT_EQ) { + continue; + } + + switch (iter->iColumn) { + case RCJ_COL_VALUE: + case RCJ_COL_PATTERN: + case RCJ_COL_FLAGS: + viu.column_used(iter); + break; + } + } + + viu.allocate_args(RCJ_COL_VALUE, RCJ_COL_FLAGS, 2); + return SQLITE_OK; +} + +static int +rcjFilter(sqlite3_vtab_cursor* pVtabCursor, + int idxNum, + const char* idxStr, + int argc, + sqlite3_value** argv) +{ + auto* pCur = (regexp_capture_into_json::cursor*) pVtabCursor; + + if (argc < 2 || argc > 3) { + pCur->c_content.clear(); + pCur->c_pattern.reset(); + pCur->c_flags_string.clear(); + pCur->c_flags = nonstd::nullopt; + return SQLITE_OK; + } + + auto byte_count = sqlite3_value_bytes(argv[0]); + const auto* blob = (const char*) sqlite3_value_blob(argv[0]); + + pCur->c_content_as_blob = (sqlite3_value_type(argv[0]) == SQLITE_BLOB); + pCur->c_content.assign(blob, byte_count); + + auto pattern = from_sqlite<string_fragment>()(argc, argv, 1); + auto compile_res = lnav::pcre2pp::code::from(pattern); + if (compile_res.isErr()) { + pVtabCursor->pVtab->zErrMsg + = sqlite3_mprintf("Invalid regular expression: %s", + compile_res.unwrapErr().get_message().c_str()); + return SQLITE_ERROR; + } + + pCur->c_flags_string.clear(); + pCur->c_flags = nonstd::nullopt; + if (argc == 3) { + static const intern_string_t FLAGS_SRC = intern_string::lookup("flags"); + const auto flags_json = from_sqlite<string_fragment>()(argc, argv, 2); + + if (!flags_json.empty()) { + const auto parse_res + = regexp_capture_flags_handlers.parser_for(FLAGS_SRC).of( + flags_json); + + if (parse_res.isErr()) { + auto um = lnav::console::user_message::error( + "unable to parse flags") + .with_reason(parse_res.unwrapErr()[0]); + + pVtabCursor->pVtab->zErrMsg = sqlite3_mprintf( + "%s%s", sqlitepp::ERROR_PREFIX, lnav::to_json(um).c_str()); + return SQLITE_ERROR; + } + + pCur->c_flags_string = flags_json.to_string(); + pCur->c_flags = parse_res.unwrap(); + } + } + + pCur->c_pattern = compile_res.unwrap().to_shared(); + pCur->c_namer + = std::make_unique<column_namer>(column_namer::language::JSON); + pCur->c_namer->add_column(string_fragment::from_const("__all__")); + for (int lpc = 1; lpc <= pCur->c_pattern->get_capture_count(); lpc++) { + pCur->c_namer->add_column(string_fragment::from_c_str( + pCur->c_pattern->get_name_for_capture(lpc))); + } + + pCur->c_match_data = pCur->c_pattern->create_match_data(); + pCur->c_remaining.clear(); + auto match_res = pCur->c_pattern->capture_from(pCur->c_content) + .into(pCur->c_match_data) + .matches(PCRE2_NO_UTF_CHECK) + .ignore_error(); + if (match_res) { + pCur->c_remaining = match_res->f_remaining; + } + pCur->c_matched = match_res.has_value(); + pCur->c_match_index = 0; + + return SQLITE_OK; +} + +int +register_regexp_vtab(sqlite3* db) +{ + static vtab_module<tvt_no_update<regexp_capture>> REGEXP_CAPTURE_MODULE; + static help_text regexp_capture_help + = help_text("regexp_capture", + "A table-valued function that executes a " + "regular-expression over a " + "string and returns the captured values. If the regex " + "only matches a " + "subset of the input string, it will be rerun on the " + "remaining parts " + "of the string until no more matches are found.") + .sql_table_valued_function() + .with_parameter( + {"string", "The string to match against the given pattern."}) + .with_parameter({"pattern", "The regular expression to match."}) + .with_result({ + "match_index", + "The match iteration. This value will increase " + "each time a new match is found in the input string.", + }) + .with_result( + {"capture_index", "The index of the capture in the regex."}) + .with_result( + {"capture_name", "The name of the capture in the regex."}) + .with_result({"capture_count", + "The total number of captures in the regex."}) + .with_result({"range_start", + "The start of the capture in the input string."}) + .with_result({"range_stop", + "The stop of the capture in the input string."}) + .with_result({"content", "The captured value from the string."}) + .with_tags({"string"}) + .with_example({ + "To extract the key/value pairs 'a'/1 and 'b'/2 " + "from the string 'a=1; b=2'", + "SELECT * FROM regexp_capture('a=1; b=2', " + "'(\\w+)=(\\d+)')", + }); + + int rc; + + REGEXP_CAPTURE_MODULE.vm_module.xBestIndex = rcBestIndex; + REGEXP_CAPTURE_MODULE.vm_module.xFilter = rcFilter; + + rc = REGEXP_CAPTURE_MODULE.create(db, "regexp_capture"); + sqlite_function_help.insert( + std::make_pair("regexp_capture", ®exp_capture_help)); + regexp_capture_help.index_tags(); + + ensure(rc == SQLITE_OK); + + static vtab_module<tvt_no_update<regexp_capture_into_json>> + REGEXP_CAPTURE_INTO_JSON_MODULE; + static help_text regexp_capture_into_json_help + = help_text( + "regexp_capture_into_json", + "A table-valued function that executes a " + "regular-expression over a string and returns the captured " + "values as a JSON object. If the regex only matches a " + "subset of the input string, it will be rerun on the " + "remaining parts of the string until no more matches are found.") + .sql_table_valued_function() + .with_parameter( + {"string", "The string to match against the given pattern."}) + .with_parameter({"pattern", "The regular expression to match."}) + .with_parameter(help_text{ + "options", + "A JSON object with the following option: " + "convert-numbers - True (default) if text that looks like " + "numeric data should be converted to JSON numbers, " + "false if they should be captured as strings."} + .optional()) + .with_result({ + "match_index", + "The match iteration. This value will increase " + "each time a new match is found in the input string.", + }) + .with_result({"content", "The captured values from the string."}) + .with_tags({"string"}) + .with_example({ + "To extract the key/value pairs 'a'/1 and 'b'/2 " + "from the string 'a=1; b=2'", + "SELECT * FROM regexp_capture_into_json('a=1; b=2', " + "'(\\w+)=(\\d+)')", + }); + + REGEXP_CAPTURE_INTO_JSON_MODULE.vm_module.xBestIndex = rcjBestIndex; + REGEXP_CAPTURE_INTO_JSON_MODULE.vm_module.xFilter = rcjFilter; + + rc = REGEXP_CAPTURE_INTO_JSON_MODULE.create(db, "regexp_capture_into_json"); + sqlite_function_help.insert(std::make_pair("regexp_capture_into_json", + ®exp_capture_into_json_help)); + regexp_capture_into_json_help.index_tags(); + + ensure(rc == SQLITE_OK); + + return rc; +} |