Let Stat() have an err outparam instead of writing to stderr.

Also check for Stat() failure in a few more places.

This way, ninja doesn't print two "ninja: error: " lines if stat() fails
during a build.  It also makes it easier to keep the stat tests quiet.
Every caller of Stat() needs to explicitly log the error string if
that's desired.

1 files changed, 16 insertions, 11 deletions

diff --git a/src/build.cc b/src/build.cc
index 1e10c7c..d898929 100644
--- a/src/build.cc
+++ b/src/build.cc
@@ -560,10 +560,12 @@ void Builder::Cleanup() {
         // need to rebuild an output because of a modified header file
         // mentioned in a depfile, and the command touches its depfile
         // but is interrupted before it touches its output file.)
-        if (!depfile.empty() ||
-            (*o)->mtime() != disk_interface_->Stat((*o)->path())) {
+        string err;
+        TimeStamp new_mtime = disk_interface_->Stat((*o)->path(), &err);
+        if (new_mtime == -1)  // Log and ignore Stat() errors.
+          Error("%s", err.c_str());
+        if (!depfile.empty() || (*o)->mtime() != new_mtime)
           disk_interface_->RemoveFile((*o)->path());
-        }
       }
       if (!depfile.empty())
         disk_interface_->RemoveFile(depfile);
@@ -760,7 +762,9 @@ bool Builder::FinishCommand(CommandRunner::Result* result, string* err) {
 
     for (vector<Node*>::iterator o = edge->outputs_.begin();
          o != edge->outputs_.end(); ++o) {
-      TimeStamp new_mtime = disk_interface_->Stat((*o)->path());
+      TimeStamp new_mtime = disk_interface_->Stat((*o)->path(), err);
+      if (new_mtime == -1)
+        return false;
       if ((*o)->mtime() == new_mtime) {
         // The rule command did not change the output.  Propagate the clean
         // state through the build graph.
@@ -776,14 +780,18 @@ bool Builder::FinishCommand(CommandRunner::Result* result, string* err) {
       // (existing) non-order-only input or the depfile.
       for (vector<Node*>::iterator i = edge->inputs_.begin();
            i != edge->inputs_.end() - edge->order_only_deps_; ++i) {
-        TimeStamp input_mtime = disk_interface_->Stat((*i)->path());
+        TimeStamp input_mtime = disk_interface_->Stat((*i)->path(), err);
+        if (input_mtime == -1)
+          return false;
         if (input_mtime > restat_mtime)
           restat_mtime = input_mtime;
       }
 
       string depfile = edge->GetUnescapedDepfile();
       if (restat_mtime != 0 && deps_type.empty() && !depfile.empty()) {
-        TimeStamp depfile_mtime = disk_interface_->Stat(depfile);
+        TimeStamp depfile_mtime = disk_interface_->Stat(depfile, err);
+        if (depfile_mtime == -1)
+          return false;
         if (depfile_mtime > restat_mtime)
           restat_mtime = depfile_mtime;
       }
@@ -812,12 +820,9 @@ bool Builder::FinishCommand(CommandRunner::Result* result, string* err) {
   if (!deps_type.empty() && !config_.dry_run) {
     assert(edge->outputs_.size() == 1 && "should have been rejected by parser");
     Node* out = edge->outputs_[0];
-    TimeStamp deps_mtime = disk_interface_->Stat(out->path());
-    if (deps_mtime == -1) {
-      // TODO: Let DiskInterface::Stat() take err instead of it calling Error().
-      *err = "stat failed";
+    TimeStamp deps_mtime = disk_interface_->Stat(out->path(), err);
+    if (deps_mtime == -1)
       return false;
-    }
     if (!scan_.deps_log()->RecordDeps(out, deps_mtime, deps_nodes)) {
       *err = string("Error writing to deps log: ") + strerror(errno);
       return false;