Make $pipestatus thread safe and other misc cleanup

src/env.cpp

@@ -1392,13 +1392,13 @@ maybe_t<env_var_t> env_stack_t::get(const wcstring &key, env_mode_flags_t mode)
             if (history) history->get_history(result);
             return env_var_t(L"history", result);
         } else if (key == L"pipestatus") {
-            const auto& js = proc_get_last_job_statuses();
+            const auto js = proc_get_last_job_statuses();
             wcstring_list_t result;
-            result.reserve(js->size());
-            for (auto&& i : *js) {
-                result.emplace_back(to_string(i));
+            result.reserve(js.size());
+            for (int i : js) {
+                result.push_back(to_string(i));
             }
-            return env_var_t(L"pipestatus", result);
+            return env_var_t(L"pipestatus", std::move(result));
         } else if (key == L"status") {
             return env_var_t(L"status", to_string(proc_get_last_status()));
         } else if (key == L"umask") {

src/event.cpp

@@ -275,7 +275,7 @@ static void event_fire_internal(const event_t &event) {
         // non-interactive.
         proc_push_interactive(0);
         int prev_status = proc_get_last_status();
-        const auto& saved_job_statuses = proc_get_last_job_statuses();
+        auto saved_job_statuses = proc_get_last_job_statuses();
         parser_t &parser = parser_t::principal_parser();
 
         event_block_t *b = parser.push_block<event_block_t>(event);

src/exec.cpp

@@ -1066,7 +1066,7 @@ static int exec_subshell_internal(const wcstring &cmd, parser_t &parser, wcstrin
     ASSERT_IS_MAIN_THREAD();
     bool prev_subshell = is_subshell;
     const int prev_status = proc_get_last_status();
-    const auto& prev_job_statuses = proc_get_last_job_statuses();
+    auto prev_job_statuses = proc_get_last_job_statuses();
     bool split_output = false;
 
     const auto ifs = parser.vars().get(L"IFS");

src/input.cpp

@@ -367,7 +367,7 @@ static void input_mapping_execute(const input_mapping_t &m, bool allow_commands)
         // FIXME(snnw): if commands add stuff to input queue (e.g. commandline -f execute), we won't
         // see that until all other commands have also been run.
         int last_status = proc_get_last_status();
-        const auto& last_job_statuses = proc_get_last_job_statuses();
+        auto last_job_statuses = proc_get_last_job_statuses();
         for (const wcstring &cmd : m.commands) {
             parser_t::principal_parser().eval(cmd, io_chain_t(), TOP);
         }

src/parse_execution.cpp

@@ -717,8 +717,9 @@ parse_execution_result_t parse_execution_context_t::handle_command_not_found(
     }
 
     // Set the last proc status appropriately.
-    proc_set_last_status(err_code == ENOENT ? STATUS_CMD_UNKNOWN : STATUS_NOT_EXECUTABLE);
-    proc_set_last_job_statuses(proc_get_last_status());
+    int status = err_code == ENOENT ? STATUS_CMD_UNKNOWN : STATUS_NOT_EXECUTABLE;
+    proc_set_last_status(status);
+    proc_set_last_job_statuses({status});
 
     return parse_execution_errored;
 }

src/proc.cpp

@@ -54,7 +54,7 @@
 static int last_status = 0;
 
 /// Statuses of last job's processes to exit - ensure we start off with one entry of 0.
-static std::shared_ptr<std::vector<int>> last_job_statuses = std::make_shared<std::vector<int>>(1);
+static owning_lock<std::vector<int>> last_job_statuses{std::vector<int>(1u, 0)};
 
 /// The signals that signify crashes to us.
 static const int crashsignals[] = {SIGABRT, SIGBUS, SIGFPE, SIGILL, SIGSEGV, SIGSYS};
@@ -144,30 +144,21 @@ int proc_get_last_status() { return last_status; }
 
 void proc_set_last_job_statuses(const job_t &last_job) {
     ASSERT_IS_MAIN_THREAD();
-    auto ljs = std::make_shared<std::vector<int>>();
-    ljs->reserve(last_job.processes.size());
-    for (auto &&p : last_job.processes) {
-        ljs->emplace_back(p->pid ? proc_format_status(p->status) : p->status);
+    std::vector<int> ljs;
+    ljs.reserve(last_job.processes.size());
+    for (const auto &p : last_job.processes) {
+        ljs.push_back(p->pid ? proc_format_status(p->status) : p->status);
     }
-    last_job_statuses = std::move(ljs);
+    proc_set_last_job_statuses(std::move(ljs));
 }
 
-void proc_set_last_job_statuses(std::shared_ptr<std::vector<int>> job_statuses) {
+void proc_set_last_job_statuses(std::vector<int> statuses) {
     ASSERT_IS_MAIN_THREAD();
-    last_job_statuses = std::move(job_statuses);
+    auto vals = last_job_statuses.acquire();
+    *vals = std::move(statuses);
 }
 
-void proc_set_last_job_statuses(const int job_status) {
-    ASSERT_IS_MAIN_THREAD();
-    auto ljs = std::make_shared<std::vector<int>>(1);
-    (*ljs)[0] = job_status;
-    last_job_statuses = std::move(ljs);
-}
-
-std::shared_ptr<std::vector<int>> proc_get_last_job_statuses() {
-    ASSERT_IS_MAIN_THREAD();
-    return last_job_statuses;
-}
+std::vector<int> proc_get_last_job_statuses() { return *last_job_statuses.acquire(); }
 
 // Basic thread safe job IDs. The vector consumed_job_ids has a true value wherever the job ID
 // corresponding to that slot is in use. The job ID corresponding to slot 0 is 1.

src/proc.h

@@ -418,11 +418,10 @@ int proc_get_last_status();
 
 /// Sets the status of the last job's processes to exit from last_job.
 void proc_set_last_job_statuses(const job_t &last_job);
-void proc_set_last_job_statuses(std::shared_ptr<std::vector<int>>);
-void proc_set_last_job_statuses(const int); // for errors where pipe is unknown
+void proc_set_last_job_statuses(std::vector<int> statuses);
 
-/// Returns the status of the last job's processes to exit.
-std::shared_ptr<std::vector<int>> proc_get_last_job_statuses();
+/// Returns the statuses of the last job's processes to exit.
+std::vector<int> proc_get_last_job_statuses();
 
 /// Notify the user about stopped or terminated jobs. Delete terminated jobs from the job list.
 ///