Date: Wed, 6 Apr 2016 17:15:45 +0300
Subject: [PATCH] [C++] Store SHELL value in command result

$(shell ...) command lines are executed using $(SHELL). We need to use
the same shell during regeneration check instead of hard-coding /bin/sh
or otherwise the results might be different when $(SHELL) is redefined
in the makefile.

Fixes https://github.com/google/kati/issues/53

Change-Id: I1f9809106f29f7e806324a82e2323a2f8df64b63
---
 func.cc  | 1 +
 func.h   | 1 +
 ninja.cc | 1 +
 regen.cc | 4 +++-
 4 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/func.cc b/func.cc
index e313c9e..42b8c62 100644
--- a/func.cc
+++ b/func.cc
@@ -569,6 +569,7 @@ void ShellFunc(const vector<Value*>& args, Evaluator* ev, string* s) {
   ShellFuncImpl(shell, cmd, &out, &fc);
   if (ShouldStoreCommandResult(cmd)) {
     CommandResult* cr = new CommandResult();
+    cr->shell = shell;
     cr->cmd = cmd;
     cr->find.reset(fc);
     cr->result = out;
diff --git a/func.h b/func.h
index 8db2c7a..e78deb7 100644
--- a/func.h
+++ b/func.h
@@ -42,6 +42,7 @@ FuncInfo* GetFuncInfo(StringPiece name);
 struct FindCommand;
 
 struct CommandResult {
+  string shell;
   string cmd;
   unique_ptr<FindCommand> find;
   string result;
diff --git a/ninja.cc b/ninja.cc
index f6e0481..41a28a5 100644
--- a/ninja.cc
+++ b/ninja.cc
@@ -735,6 +735,7 @@ class NinjaGenerator {
     const vector<CommandResult*>& crs = GetShellCommandResults();
     DumpInt(fp, crs.size());
     for (CommandResult* cr : crs) {
+      DumpString(fp, cr->shell);
       DumpString(fp, cr->cmd);
       DumpString(fp, cr->result);
       if (!cr->find.get()) {
diff --git a/regen.cc b/regen.cc
index 23151b4..3d03f67 100644
--- a/regen.cc
+++ b/regen.cc
@@ -52,6 +52,7 @@ class StampChecker {
   };
 
   struct ShellResult {
+    string shell;
     string cmd;
     string result;
     vector<string> missing_dirs;
@@ -230,6 +231,7 @@ class StampChecker {
     for (int i = 0; i < num_crs; i++) {
       ShellResult* sr = new ShellResult;
       commands_.push_back(sr);
+      LOAD_STRING(fp, &sr->shell);
       LOAD_STRING(fp, &sr->cmd);
       LOAD_STRING(fp, &sr->result);
       sr->has_condition = LOAD_INT(fp);
@@ -339,7 +341,7 @@ class StampChecker {
 
     COLLECT_STATS_WITH_SLOW_REPORT("shell time (regen)", sr->cmd.c_str());
     string result;
-    RunCommand("/bin/sh", sr->cmd, RedirectStderr::DEV_NULL, &result);
+    RunCommand(sr->shell, sr->cmd, RedirectStderr::DEV_NULL, &result);
     FormatForCommandSubstitution(&result);
     if (sr->result != result) {
       if (g_flags.dump_kati_stamp) {
-- 
2.5.5