diff options
Diffstat (limited to 'libbuild2/build/script/script.hxx')
| -rw-r--r-- | libbuild2/build/script/script.hxx | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/libbuild2/build/script/script.hxx b/libbuild2/build/script/script.hxx new file mode 100644 index 0000000..2118568 --- /dev/null +++ b/libbuild2/build/script/script.hxx @@ -0,0 +1,156 @@ +// file : libbuild2/build/script/script.hxx -*- C++ -*- +// license : MIT; see accompanying LICENSE file + +#ifndef LIBBUILD2_BUILD_SCRIPT_SCRIPT_HXX +#define LIBBUILD2_BUILD_SCRIPT_SCRIPT_HXX + +#include <libbuild2/types.hxx> +#include <libbuild2/forward.hxx> +#include <libbuild2/utility.hxx> + +#include <libbuild2/variable.hxx> +#include <libbuild2/filesystem.hxx> // auto_rmdir + +#include <libbuild2/script/script.hxx> + +namespace build2 +{ + namespace build + { + namespace script + { + using build2::script::line; + using build2::script::line_type; + using build2::script::redirect; + using build2::script::redirect_type; + using build2::script::expr_term; + using build2::script::command_expr; + + // Notes: + // + // - Once parsed, the script can be executed in multiple threads with + // the state (variable values, etc) maintained in the environment. + // + // - The default script command redirects semantics is 'none' for stdin, + // 'merge' into stderr for stdout, and 'pass' for stderr. + // + class script + { + public: + // Note that the variables are not pre-entered into a pool during the + // parsing phase, so the line variable pointers are NULL. + // + build2::script::lines lines; + + // Referenced ordinary (non-special) variables. + // + // Used for the script semantics change tracking. The variable list is + // filled during the pre-parsing phase and is checked against during + // the execution phase. If during execution some non-script-local + // variable is not found in the list (may happen for a computed name), + // then the execution fails since the script semantics may not be + // properly tracked (the variable value change will not trigger the + // target rebuild). + // + small_vector<string, 2> vars; // 2 for command and options. + + // True if script references the $~ special variable. + // + bool temp_dir = false; + + location start_loc; + location end_loc; + }; + + class environment: public build2::script::environment + { + public: + using target_type = build2::target; + + environment (action, const target_type&, bool temp_dir); + + environment (environment&&) = delete; + environment (const environment&) = delete; + environment& operator= (environment&&) = delete; + environment& operator= (const environment&) = delete; + + public: + // Primary target this environment is for. + // + const target_type& target; + + // Script-local variable pool and map. + // + // Note that if we lookup the variable by passing name as a string, + // then it will be looked up in the wrong pool. + // + variable_pool var_pool; + variable_map vars; + + // Temporary directory for the script run. + // + // Currently this directory is removed regardless of the script + // execution success or failure. Later, to help with troubleshooting, + // we may invent an option that suppresses the removal of temporary + // files in general. + // + // This directory is available to the user via the $~ special + // variable. Note, however, that the following filesystem entry + // prefixes are reserved: + // + // stdin* + // stdout* + // stderr* + // + auto_rmdir temp_dir; + + virtual void + set_variable (string&& name, + names&&, + const string& attrs, + const location&) override; + + virtual void + create_temp_dir () override; + + // Variables. + // + public: + // Lookup the variable starting from this environment, then the + // primary target, and then outer buildfile scopes. + // + using lookup_type = build2::lookup; + + lookup_type + lookup (const variable&) const; + + lookup_type + lookup (const string&) const; + + // As above but only look for buildfile variables. + // + lookup_type + lookup_in_buildfile (const string&) const; + + // Return a value suitable for assignment. If the variable does not + // exist in this environment's variable map, then a new one with the + // NULL value is added and returned. Otherwise the existing value is + // returned. + // + value& + assign (const variable& var) {return vars.assign (var);} + + // Return a value suitable for append/prepend. If the variable does + // not exist in this environment's variable map, then outer scopes are + // searched for the same variable. If found then a new variable with + // the found value is added to the environment and returned. Otherwise + // this function proceeds as assign() above. + // + value& + append (const variable&); + }; + } + } +} + +#endif // LIBBUILD2_BUILD_SCRIPT_SCRIPT_HXX |