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Diffstat (limited to 'libbuild2/script/parser.hxx')
| -rw-r--r-- | libbuild2/script/parser.hxx | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/libbuild2/script/parser.hxx b/libbuild2/script/parser.hxx new file mode 100644 index 0000000..a63ecde --- /dev/null +++ b/libbuild2/script/parser.hxx @@ -0,0 +1,189 @@ +// file : libbuild2/script/parser.hxx -*- C++ -*- +// license : MIT; see accompanying LICENSE file + +#ifndef LIBBUILD2_SCRIPT_PARSER_HXX +#define LIBBUILD2_SCRIPT_PARSER_HXX + +#include <libbuild2/types.hxx> +#include <libbuild2/forward.hxx> +#include <libbuild2/utility.hxx> + +#include <libbuild2/parser.hxx> +#include <libbuild2/diagnostics.hxx> + +#include <libbuild2/script/token.hxx> +#include <libbuild2/script/lexer.hxx> // redirect_aliases +#include <libbuild2/script/script.hxx> + +namespace build2 +{ + namespace script + { + class lexer; + struct lexer_mode; + + class parser: protected build2::parser + { + public: + parser (context& c): build2::parser (c) {} + + // Helpers. + // + // Parse attribute string and perform attribute-guided assignment. + // Issue diagnostics and throw failed in case of an error. + // + void + apply_value_attributes (const variable*, // Optional. + value& lhs, + value&& rhs, + const string& attributes, + token_type assign_kind, + const path_name&); // For diagnostics. + + using build2::parser::apply_value_attributes; + + // Commonly used parsing functions. Issue diagnostics and throw failed + // in case of an error. + // + // Usually (but not always) parse functions receive the token/type + // from which it should start consuming and in return the token/type + // should contain the first token that has not been consumed. + // + // Functions that are called parse_*() rather than pre_parse_*() can be + // used for both stages. + // + protected: + value + parse_variable_line (token&, token_type&); + + // Ordered sequence of here-document redirects that we can expect to + // see after the command line. + // + struct here_redirect + { + size_t expr; // Index in command_expr. + size_t pipe; // Index in command_pipe. + int fd; // Redirect fd (0 - in, 1 - out, 2 - err). + }; + + struct here_doc + { + // Redirects that share here_doc. Most of the time we will have no + // more than 2 (2 - for the roundtrip cases). Doesn't refer overridden + // redirects and thus can be empty. + // + small_vector<here_redirect, 2> redirects; + + string end; + bool literal; // Literal (single-quote). + string modifiers; + + // Regex introducer ('\0' if not a regex, so can be used as bool). + // + char regex; + + // Regex global flags. Meaningful if regex != '\0'. + // + string regex_flags; + }; + using here_docs = vector<here_doc>; + + pair<command_expr, here_docs> + parse_command_expr (token&, token_type&, const redirect_aliases&); + + command_exit + parse_command_exit (token&, token_type&); + + void + parse_here_documents (token&, token_type&, + pair<command_expr, here_docs>&); + + struct parsed_doc + { + union + { + string str; // Here-document literal. + regex_lines regex; // Here-document regex. + }; + + bool re; // True if regex. + uint64_t end_line; // Here-document end marker location. + uint64_t end_column; + + parsed_doc (string, uint64_t line, uint64_t column); + parsed_doc (regex_lines&&, uint64_t line, uint64_t column); + parsed_doc (parsed_doc&&); // Note: move constuctible-only type. + ~parsed_doc (); + }; + + parsed_doc + parse_here_document (token&, token_type&, + const string&, + const string& mode, + char re_intro); // '\0' if not a regex. + + // Start pre-parsing a script line returning its type, detected based on + // the first two tokens. Use the specified lexer mode to peek the second + // token. + // + line_type + pre_parse_line_start (token&, token_type&, lexer_mode); + + // Execute. + // + protected: + // Return false if the execution of the script should be terminated with + // the success status (e.g., as a result of encountering the exit + // builtin). For unsuccessful termination the failed exception is thrown. + // + using exec_set_function = void (const variable&, + token&, token_type&, + const location&); + + using exec_cmd_function = void (token&, token_type&, + size_t li, + bool single, + const location&); + + using exec_if_function = bool (token&, token_type&, + size_t li, + const location&); + + // If a parser implementation doesn't pre-enter variables into a pool + // during the pre-parsing phase, then they are entered during the + // execution phase and so the variable pool must be provided. Note that + // in this case the variable pool insertions are not MT-safe. + // + bool + exec_lines (lines::const_iterator b, lines::const_iterator e, + const function<exec_set_function>&, + const function<exec_cmd_function>&, + const function<exec_if_function>&, + size_t& li, + variable_pool* = nullptr); + + // Set lexer pointers for both the current and the base classes. + // + protected: + void + set_lexer (lexer*); + + // Number of quoted tokens since last reset. Note that this includes + // the peeked token, if any. + // + protected: + size_t + quoted () const; + + void + reset_quoted (token& current); + + size_t replay_quoted_; + + protected: + lexer* lexer_ = nullptr; + }; + } +} + +#endif // LIBBUILD2_SCRIPT_PARSER_HXX |