ART: Cut filename for DumpCFG
If the name/path is too long, we'd silently fail dumping. Cut the
name when it's too long, and write an error message if we still
fail opening.
Change-Id: Id439a3367a8fdb50027959dd8c183913d074e669
diff --git a/compiler/dex/mir_graph.cc b/compiler/dex/mir_graph.cc
index 312a6eb..abd3482 100644
--- a/compiler/dex/mir_graph.cc
+++ b/compiler/dex/mir_graph.cc
@@ -18,6 +18,7 @@
#include <inttypes.h>
#include <queue>
+#include <unistd.h>
#include "base/bit_vector-inl.h"
#include "base/stl_util.h"
@@ -876,6 +877,34 @@
return GetDataFlowAttributes(opcode);
}
+// The path can easily surpass FS limits because of parameters etc. Use pathconf to get FS
+// restrictions here. Note that a successful invocation will return an actual value. If the path
+// is too long for some reason, the return will be ENAMETOOLONG. Then cut off part of the name.
+//
+// It's possible the path is not valid, or some other errors appear. In that case return false.
+static bool CreateDumpFile(std::string& fname, const char* dir_prefix, NarrowDexOffset start_offset,
+ const char *suffix, int nr, std::string* output) {
+ std::string dir = StringPrintf("./%s", dir_prefix);
+ int64_t max_name_length = pathconf(dir.c_str(), _PC_NAME_MAX);
+ if (max_name_length <= 0) {
+ PLOG(ERROR) << "Could not get file name restrictions for " << dir;
+ return false;
+ }
+
+ std::string name = StringPrintf("%s%x%s_%d.dot", fname.c_str(), start_offset,
+ suffix == nullptr ? "" : suffix, nr);
+ std::string fpath;
+ if (static_cast<int64_t>(name.size()) > max_name_length) {
+ std::string suffix_str = StringPrintf("_%d.dot", nr);
+ name = name.substr(0, static_cast<size_t>(max_name_length) - suffix_str.size()) + suffix_str;
+ }
+ // Sanity check.
+ DCHECK_LE(name.size(), static_cast<size_t>(max_name_length));
+
+ *output = StringPrintf("%s%s", dir_prefix, name.c_str());
+ return true;
+}
+
// TODO: use a configurable base prefix, and adjust callers to supply pass name.
/* Dump the CFG into a DOT graph */
void MIRGraph::DumpCFG(const char* dir_prefix, bool all_blocks, const char *suffix) {
@@ -884,15 +913,19 @@
// Increment counter to get a unique file number.
cnt++;
+ int nr = cnt.LoadRelaxed();
std::string fname(PrettyMethod(cu_->method_idx, *cu_->dex_file));
ReplaceSpecialChars(fname);
- fname = StringPrintf("%s%s%x%s_%d.dot", dir_prefix, fname.c_str(),
- GetBasicBlock(GetEntryBlock()->fall_through)->start_offset,
- suffix == nullptr ? "" : suffix,
- cnt.LoadRelaxed());
- file = fopen(fname.c_str(), "w");
+ std::string fpath;
+ if (!CreateDumpFile(fname, dir_prefix, GetBasicBlock(GetEntryBlock()->fall_through)->start_offset,
+ suffix, nr, &fpath)) {
+ LOG(ERROR) << "Could not create dump file name for " << fname;
+ return;
+ }
+ file = fopen(fpath.c_str(), "w");
if (file == NULL) {
+ PLOG(ERROR) << "Could not open " << fpath << " for DumpCFG.";
return;
}
fprintf(file, "digraph G {\n");