malloc_debug: reread /proc/pid/maps when entry is missing
Reread /proc/pid/maps on demand in case a new library has been loaded.
Change-Id: Iac8109b3e6a07bf02c38300b21eecabf4bcd54df
diff --git a/libc/malloc_debug/MapData.cpp b/libc/malloc_debug/MapData.cpp
index c38362b..8e9c806 100644
--- a/libc/malloc_debug/MapData.cpp
+++ b/libc/malloc_debug/MapData.cpp
@@ -110,7 +110,7 @@
}
}
-bool MapData::Initialize() {
+bool MapData::ReadMaps() {
FILE* fp = fopen("/proc/self/maps", "re");
if (fp == nullptr) {
return false;
@@ -120,23 +120,21 @@
while (fgets(buffer.data(), buffer.size(), fp) != nullptr) {
MapEntry* entry = parse_line(buffer.data());
if (entry == nullptr) {
+ fclose(fp);
return false;
}
- entries_.push_back(entry);
+
+ auto it = entries_.find(entry);
+ if (it == entries_.end()) {
+ entries_.insert(entry);
+ } else {
+ delete entry;
+ }
}
fclose(fp);
return true;
}
-MapData* MapData::Create() {
- MapData* maps = new MapData();
- if (!maps->Initialize()) {
- delete maps;
- return nullptr;
- }
- return maps;
-}
-
MapData::~MapData() {
for (auto* entry : entries_) {
delete entry;
@@ -146,19 +144,25 @@
// Find the containing map info for the PC.
const MapEntry* MapData::find(uintptr_t pc, uintptr_t* rel_pc) {
- for (auto* entry : entries_) {
- if ((pc >= entry->start) && (pc < entry->end)) {
- if (!entry->load_base_read) {
- read_loadbase(entry);
- }
- if (rel_pc) {
- *rel_pc = pc - entry->start + entry->load_base;
- }
- return entry;
- }
+ MapEntry pc_entry(pc);
+
+ std::lock_guard<std::mutex> lock(m_);
+
+ auto it = entries_.find(&pc_entry);
+ if (it == entries_.end()) {
+ ReadMaps();
+ }
+ it = entries_.find(&pc_entry);
+ if (it == entries_.end()) {
+ return nullptr;
+ }
+
+ MapEntry *entry = *it;
+ if (!entry->load_base_read) {
+ read_loadbase(entry);
}
if (rel_pc) {
- *rel_pc = pc;
+ *rel_pc = pc - entry->start + entry->load_base;
}
- return nullptr;
+ return entry;
}