From 126d6ab2b69417e2f1ad0d182443838fed073372 Mon Sep 17 00:00:00 2001
From: Daniel Kolesa <daniel@octaforge.org>
Date: Fri, 19 Mar 2021 01:31:34 +0100
Subject: [PATCH] use a stolen buffer for strupper/lower

---
 include/cubescript/cubescript.hh |  3 +++
 src/cs_vm.hh                     |  8 ++++++++
 src/lib_str.cc                   | 29 ++++++++++++++++++++---------
 3 files changed, 31 insertions(+), 9 deletions(-)

diff --git a/include/cubescript/cubescript.hh b/include/cubescript/cubescript.hh
index d48b285..8abeb8e 100644
--- a/include/cubescript/cubescript.hh
+++ b/include/cubescript/cubescript.hh
@@ -70,6 +70,8 @@ OSTD_EXPORT bool cs_code_is_empty(cs_bcode *code);
 
 struct OSTD_EXPORT cs_strref {
     friend struct cs_value;
+    /* FIXME: eliminate this */
+    friend inline cs_strref cs_make_strref(char const *p, cs_shared_state &cs);
 
     cs_strref() = delete;
     cs_strref(cs_shared_state &cs, ostd::string_range str);
@@ -381,6 +383,7 @@ struct OSTD_EXPORT cs_state {
     friend struct cs_strref;
     friend struct cs_value;
     friend struct cs_gen_state;
+    friend inline cs_shared_state *cs_get_sstate(cs_state &);
 
     cs_shared_state *p_state;
     cs_ident_link *p_callstack = nullptr;
diff --git a/src/cs_vm.hh b/src/cs_vm.hh
index 29bb898..a63b1ce 100644
--- a/src/cs_vm.hh
+++ b/src/cs_vm.hh
@@ -155,6 +155,14 @@ struct cs_shared_state {
     }
 };
 
+inline cs_shared_state *cs_get_sstate(cs_state &cs) {
+    return cs.p_state;
+}
+
+inline cs_strref cs_make_strref(char const *p, cs_shared_state &cs) {
+    return cs_strref{p, cs};
+}
+
 struct CsBreakException {
 };
 
diff --git a/src/lib_str.cc b/src/lib_str.cc
index 1c75d2f..0bd197f 100644
--- a/src/lib_str.cc
+++ b/src/lib_str.cc
@@ -3,6 +3,7 @@
 #include <cubescript/cubescript.hh>
 
 #include "cs_util.hh"
+#include "cs_vm.hh"
 
 namespace cscript {
 
@@ -56,20 +57,30 @@ void cs_init_lib_string(cs_state &cs) {
         res.set_str(ostd::string_range{static_cast<char const *>(p)});
     });
 
-    cs.new_command("strlower", "s", [](auto &, auto args, auto &res) {
-        cs_string s{ostd::string_range{args[0].get_str()}};
-        for (auto i: ostd::range(s.size())) {
-            s[i] = tolower(s[i]);
+    cs.new_command("strlower", "s", [](auto &ccs, auto args, auto &res) {
+        auto inps = ostd::string_range{args[0].get_str()};
+        auto *ics = cs_get_sstate(ccs);
+        auto *buf = ics->strman->alloc_buf(inps.size());
+        for (auto i: ostd::range(inps.size())) {
+            buf[i] = tolower(inps[i]);
         }
-        res.set_str(s);
+        auto const *cbuf = ics->strman->steal(buf);
+        auto sr = cs_make_strref(cbuf, *ics);
+        sman->unref(cbuf);
+        res.set_str(sr);
     });
 
     cs.new_command("strupper", "s", [](auto &, auto args, auto &res) {
-        cs_string s{ostd::string_range{args[0].get_str()}};
-        for (auto i: ostd::range(s.size())) {
-            s[i] = toupper(s[i]);
+        auto inps = ostd::string_range{args[0].get_str()};
+        auto *ics = cs_get_sstate(ccs);
+        auto *buf = ics->strman->alloc_buf(inps.size());
+        for (auto i: ostd::range(inps.size())) {
+            buf[i] = toupper(inps[i]);
         }
-        res.set_str(s);
+        auto const *cbuf = ics->strman->steal(buf);
+        auto sr = cs_make_strref(cbuf, *ics);
+        sman->unref(cbuf);
+        res.set_str(sr);
     });
 
     cs.new_command("escape", "s", [](auto &, auto args, auto &res) {