Merge branch 'master' into iwyu

src/function.cpp

@@ -0,0 +1,389 @@
+/** \file function.c
+
+    Prototypes for functions for storing and retrieving function
+  information. These functions also take care of autoloading
+  functions in the $fish_function_path. Actual function evaluation
+  is taken care of by the parser and to some degree the builtin
+  handling library.
+*/
+
+#include "config.h" // IWYU pragma: keep
+
+#include <wchar.h>
+#include <pthread.h>
+#include <map>
+#include <set>
+#include <dirent.h>
+#include <stddef.h>
+#include <string>
+#include <utility>
+
+#include "wutil.h"
+#include "fallback.h" // IWYU pragma: keep
+
+#include "autoload.h"
+#include "function.h"
+#include "common.h"
+#include "intern.h"
+#include "event.h"
+#include "reader.h"
+#include "parser_keywords.h"
+#include "env.h"
+
+/**
+   Table containing all functions
+*/
+typedef std::map<wcstring, function_info_t> function_map_t;
+static function_map_t loaded_functions;
+
+/**
+   Functions that shouldn't be autoloaded (anymore).
+*/
+static std::set<wcstring> function_tombstones;
+
+/* Lock for functions */
+static pthread_mutex_t functions_lock;
+
+/* Autoloader for functions */
+class function_autoload_t : public autoload_t
+{
+public:
+    function_autoload_t();
+    virtual void command_removed(const wcstring &cmd);
+};
+
+static function_autoload_t function_autoloader;
+
+/** Constructor */
+function_autoload_t::function_autoload_t() : autoload_t(L"fish_function_path", NULL, 0)
+{
+}
+
+static bool function_remove_ignore_autoload(const wcstring &name, bool tombstone = true);
+
+/** Callback when an autoloaded function is removed */
+void function_autoload_t::command_removed(const wcstring &cmd)
+{
+    function_remove_ignore_autoload(cmd, false);
+}
+
+/**
+   Kludgy flag set by the load function in order to tell function_add
+   that the function being defined is autoloaded. There should be a
+   better way to do this...
+*/
+static bool is_autoload = false;
+
+/**
+   Make sure that if the specified function is a dynamically loaded
+   function, it has been fully loaded.
+*/
+static int load(const wcstring &name)
+{
+    ASSERT_IS_MAIN_THREAD();
+    scoped_lock lock(functions_lock);
+    bool was_autoload = is_autoload;
+    int res;
+
+    bool no_more_autoload = function_tombstones.count(name) > 0;
+    if (no_more_autoload)
+        return 0;
+
+    function_map_t::iterator iter = loaded_functions.find(name);
+    if (iter !=  loaded_functions.end() && !iter->second.is_autoload)
+    {
+        /* We have a non-autoload version already */
+        return 0;
+    }
+
+    is_autoload = true;
+    res = function_autoloader.load(name, true);
+    is_autoload = was_autoload;
+    return res;
+}
+
+/**
+   Insert a list of all dynamically loaded functions into the
+   specified list.
+*/
+static void autoload_names(std::set<wcstring> &names, int get_hidden)
+{
+    size_t i;
+
+    const env_var_t path_var_wstr =  env_get_string(L"fish_function_path");
+    if (path_var_wstr.missing())
+        return;
+    const wchar_t *path_var = path_var_wstr.c_str();
+
+    wcstring_list_t path_list;
+
+    tokenize_variable_array(path_var, path_list);
+    for (i=0; i<path_list.size(); i++)
+    {
+        const wcstring &ndir_str = path_list.at(i);
+        const wchar_t *ndir = (wchar_t *)ndir_str.c_str();
+        DIR *dir = wopendir(ndir);
+        if (!dir)
+            continue;
+
+        wcstring name;
+        while (wreaddir(dir, name))
+        {
+            const wchar_t *fn = name.c_str();
+            const wchar_t *suffix;
+            if (!get_hidden && fn[0] == L'_')
+                continue;
+
+            suffix = wcsrchr(fn, L'.');
+            if (suffix && (wcscmp(suffix, L".fish") == 0))
+            {
+                wcstring name(fn, suffix - fn);
+                names.insert(name);
+            }
+        }
+        closedir(dir);
+    }
+}
+
+void function_init()
+{
+    /* PCA: This recursive lock was introduced early in my work. I would like to make this a non-recursive lock but I haven't fully investigated all the call paths (for autoloading functions, etc.) */
+    pthread_mutexattr_t a;
+    VOMIT_ON_FAILURE(pthread_mutexattr_init(&a));
+    VOMIT_ON_FAILURE(pthread_mutexattr_settype(&a,PTHREAD_MUTEX_RECURSIVE));
+    VOMIT_ON_FAILURE(pthread_mutex_init(&functions_lock, &a));
+    VOMIT_ON_FAILURE(pthread_mutexattr_destroy(&a));
+}
+
+static std::map<wcstring,env_var_t> snapshot_vars(const wcstring_list_t &vars)
+{
+    std::map<wcstring,env_var_t> result;
+    for (wcstring_list_t::const_iterator it = vars.begin(), end = vars.end(); it != end; ++it)
+    {
+        result.insert(std::make_pair(*it, env_get_string(*it)));
+    }
+    return result;
+}
+
+function_info_t::function_info_t(const function_data_t &data, const wchar_t *filename, int def_offset, bool autoload) :
+    definition(data.definition),
+    description(data.description),
+    definition_file(intern(filename)),
+    definition_offset(def_offset),
+    named_arguments(data.named_arguments),
+    inherit_vars(snapshot_vars(data.inherit_vars)),
+    is_autoload(autoload),
+    shadows(data.shadows)
+{
+}
+
+function_info_t::function_info_t(const function_info_t &data, const wchar_t *filename, int def_offset, bool autoload) :
+    definition(data.definition),
+    description(data.description),
+    definition_file(intern(filename)),
+    definition_offset(def_offset),
+    named_arguments(data.named_arguments),
+    inherit_vars(data.inherit_vars),
+    is_autoload(autoload),
+    shadows(data.shadows)
+{
+}
+
+void function_add(const function_data_t &data, const parser_t &parser, int definition_line_offset)
+{
+    ASSERT_IS_MAIN_THREAD();
+
+    CHECK(! data.name.empty(),);
+    CHECK(data.definition,);
+    scoped_lock lock(functions_lock);
+
+    /* Remove the old function */
+    function_remove(data.name);
+
+    /* Create and store a new function */
+    const wchar_t *filename = reader_current_filename();
+
+    const function_map_t::value_type new_pair(data.name, function_info_t(data, filename, definition_line_offset, is_autoload));
+    loaded_functions.insert(new_pair);
+
+    /* Add event handlers */
+    for (std::vector<event_t>::const_iterator iter = data.events.begin(); iter != data.events.end(); ++iter)
+    {
+        event_add_handler(*iter);
+    }
+}
+
+int function_exists(const wcstring &cmd)
+{
+    if (parser_keywords_is_reserved(cmd))
+        return 0;
+    scoped_lock lock(functions_lock);
+    load(cmd);
+    return loaded_functions.find(cmd) != loaded_functions.end();
+}
+
+int function_exists_no_autoload(const wcstring &cmd, const env_vars_snapshot_t &vars)
+{
+    if (parser_keywords_is_reserved(cmd))
+        return 0;
+    scoped_lock lock(functions_lock);
+    return loaded_functions.find(cmd) != loaded_functions.end() || function_autoloader.can_load(cmd, vars);
+}
+
+static bool function_remove_ignore_autoload(const wcstring &name, bool tombstone)
+{
+    // Note: the lock may be held at this point, but is recursive
+    scoped_lock lock(functions_lock);
+
+    function_map_t::iterator iter = loaded_functions.find(name);
+
+    // not found.  not erasing.
+    if (iter == loaded_functions.end())
+        return false;
+
+    // removing an auto-loaded function.  prevent it from being
+    // auto-reloaded.
+    if (iter->second.is_autoload && tombstone)
+        function_tombstones.insert(name);
+
+    loaded_functions.erase(iter);
+
+    event_t ev(EVENT_ANY);
+    ev.function_name=name;
+    event_remove(ev);
+
+    return true;
+}
+
+void function_remove(const wcstring &name)
+{
+    if (function_remove_ignore_autoload(name))
+        function_autoloader.unload(name);
+}
+
+static const function_info_t *function_get(const wcstring &name)
+{
+    // The caller must lock the functions_lock before calling this; however our mutex is currently recursive, so trylock will never fail
+    // We need a way to correctly check if a lock is locked (or better yet, make our lock non-recursive)
+    //ASSERT_IS_LOCKED(functions_lock);
+    function_map_t::iterator iter = loaded_functions.find(name);
+    if (iter == loaded_functions.end())
+    {
+        return NULL;
+    }
+    else
+    {
+        return &iter->second;
+    }
+}
+
+bool function_get_definition(const wcstring &name, wcstring *out_definition)
+{
+    scoped_lock lock(functions_lock);
+    const function_info_t *func = function_get(name);
+    if (func && out_definition)
+    {
+        out_definition->assign(func->definition);
+    }
+    return func != NULL;
+}
+
+wcstring_list_t function_get_named_arguments(const wcstring &name)
+{
+    scoped_lock lock(functions_lock);
+    const function_info_t *func = function_get(name);
+    return func ? func->named_arguments : wcstring_list_t();
+}
+
+std::map<wcstring,env_var_t> function_get_inherit_vars(const wcstring &name)
+{
+    scoped_lock lock(functions_lock);
+    const function_info_t *func = function_get(name);
+    return func ? func->inherit_vars : std::map<wcstring,env_var_t>();
+}
+
+int function_get_shadows(const wcstring &name)
+{
+    scoped_lock lock(functions_lock);
+    const function_info_t *func = function_get(name);
+    return func ? func->shadows : false;
+}
+
+
+bool function_get_desc(const wcstring &name, wcstring *out_desc)
+{
+    /* Empty length string goes to NULL */
+    scoped_lock lock(functions_lock);
+    const function_info_t *func = function_get(name);
+    if (out_desc && func && ! func->description.empty())
+    {
+        out_desc->assign(_(func->description.c_str()));
+        return true;
+    }
+    else
+    {
+        return false;
+    }
+}
+
+void function_set_desc(const wcstring &name, const wcstring &desc)
+{
+    load(name);
+    scoped_lock lock(functions_lock);
+    function_map_t::iterator iter = loaded_functions.find(name);
+    if (iter != loaded_functions.end())
+    {
+        iter->second.description = desc;
+    }
+}
+
+bool function_copy(const wcstring &name, const wcstring &new_name)
+{
+    bool result = false;
+    scoped_lock lock(functions_lock);
+    function_map_t::const_iterator iter = loaded_functions.find(name);
+    if (iter != loaded_functions.end())
+    {
+        // This new instance of the function shouldn't be tied to the definition file of the original, so pass NULL filename, etc.
+        const function_map_t::value_type new_pair(new_name, function_info_t(iter->second, NULL, 0, false));
+        loaded_functions.insert(new_pair);
+        result = true;
+    }
+    return result;
+}
+
+wcstring_list_t function_get_names(int get_hidden)
+{
+    std::set<wcstring> names;
+    scoped_lock lock(functions_lock);
+    autoload_names(names, get_hidden);
+
+    function_map_t::const_iterator iter;
+    for (iter = loaded_functions.begin(); iter != loaded_functions.end(); ++iter)
+    {
+        const wcstring &name = iter->first;
+
+        /* Maybe skip hidden */
+        if (! get_hidden)
+        {
+            if (name.empty() || name.at(0) == L'_') continue;
+        }
+        names.insert(name);
+    }
+    return wcstring_list_t(names.begin(), names.end());
+}
+
+const wchar_t *function_get_definition_file(const wcstring &name)
+{
+    scoped_lock lock(functions_lock);
+    const function_info_t *func = function_get(name);
+    return func ? func->definition_file : NULL;
+}
+
+
+int function_get_definition_offset(const wcstring &name)
+{
+    scoped_lock lock(functions_lock);
+    const function_info_t *func = function_get(name);
+    return func ? func->definition_offset : -1;
+}