1 files changed, 176 insertions, 0 deletions
diff --git a/libsanitizer/sanitizer_common/sanitizer_procmaps_common.cc b/libsanitizer/sanitizer_common/sanitizer_procmaps_common.cc
new file mode 100644
index 00000000000..ca9900fe9ee
--- /dev/null
+++ b/libsanitizer/sanitizer_common/sanitizer_procmaps_common.cc
@@ -0,0 +1,176 @@
+//===-- sanitizer_procmaps_common.cc --------------------------------------===//
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Information about the process mappings (common parts).
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_platform.h"
+#if SANITIZER_FREEBSD || SANITIZER_LINUX
+#include "sanitizer_common.h"
+#include "sanitizer_placement_new.h"
+#include "sanitizer_procmaps.h"
+
+namespace __sanitizer {
+
+// Linker initialized.
+ProcSelfMapsBuff MemoryMappingLayout::cached_proc_self_maps_;
+StaticSpinMutex MemoryMappingLayout::cache_lock_;  // Linker initialized.
+
+static int TranslateDigit(char c) {
+  if (c >= '0' && c <= '9')
+    return c - '0';
+  if (c >= 'a' && c <= 'f')
+    return c - 'a' + 10;
+  if (c >= 'A' && c <= 'F')
+    return c - 'A' + 10;
+  return -1;
+}
+
+// Parse a number and promote 'p' up to the first non-digit character.
+static uptr ParseNumber(const char **p, int base) {
+  uptr n = 0;
+  int d;
+  CHECK(base >= 2 && base <= 16);
+  while ((d = TranslateDigit(**p)) >= 0 && d < base) {
+    n = n * base + d;
+    (*p)++;
+  }
+  return n;
+}
+
+bool IsDecimal(char c) {
+  int d = TranslateDigit(c);
+  return d >= 0 && d < 10;
+}
+
+uptr ParseDecimal(const char **p) {
+  return ParseNumber(p, 10);
+}
+
+bool IsHex(char c) {
+  int d = TranslateDigit(c);
+  return d >= 0 && d < 16;
+}
+
+uptr ParseHex(const char **p) {
+  return ParseNumber(p, 16);
+}
+
+MemoryMappingLayout::MemoryMappingLayout(bool cache_enabled) {
+  ReadProcMaps(&proc_self_maps_);
+  if (cache_enabled) {
+    if (proc_self_maps_.mmaped_size == 0) {
+      LoadFromCache();
+      CHECK_GT(proc_self_maps_.len, 0);
+    }
+  } else {
+    CHECK_GT(proc_self_maps_.mmaped_size, 0);
+  }
+  Reset();
+  // FIXME: in the future we may want to cache the mappings on demand only.
+  if (cache_enabled)
+    CacheMemoryMappings();
+}
+
+MemoryMappingLayout::~MemoryMappingLayout() {
+  // Only unmap the buffer if it is different from the cached one. Otherwise
+  // it will be unmapped when the cache is refreshed.
+  if (proc_self_maps_.data != cached_proc_self_maps_.data) {
+    UnmapOrDie(proc_self_maps_.data, proc_self_maps_.mmaped_size);
+  }
+}
+
+void MemoryMappingLayout::Reset() {
+  current_ = proc_self_maps_.data;
+}
+
+// static
+void MemoryMappingLayout::CacheMemoryMappings() {
+  SpinMutexLock l(&cache_lock_);
+  // Don't invalidate the cache if the mappings are unavailable.
+  ProcSelfMapsBuff old_proc_self_maps;
+  old_proc_self_maps = cached_proc_self_maps_;
+  ReadProcMaps(&cached_proc_self_maps_);
+  if (cached_proc_self_maps_.mmaped_size == 0) {
+    cached_proc_self_maps_ = old_proc_self_maps;
+  } else {
+    if (old_proc_self_maps.mmaped_size) {
+      UnmapOrDie(old_proc_self_maps.data,
+                 old_proc_self_maps.mmaped_size);
+    }
+  }
+}
+
+void MemoryMappingLayout::LoadFromCache() {
+  SpinMutexLock l(&cache_lock_);
+  if (cached_proc_self_maps_.data) {
+    proc_self_maps_ = cached_proc_self_maps_;
+  }
+}
+
+uptr MemoryMappingLayout::DumpListOfModules(LoadedModule *modules,
+                                            uptr max_modules,
+                                            string_predicate_t filter) {
+  Reset();
+  uptr cur_beg, cur_end, cur_offset, prot;
+  InternalScopedBuffer<char> module_name(kMaxPathLength);
+  uptr n_modules = 0;
+  for (uptr i = 0; n_modules < max_modules &&
+                       Next(&cur_beg, &cur_end, &cur_offset, module_name.data(),
+                            module_name.size(), &prot);
+       i++) {
+    const char *cur_name = module_name.data();
+    if (cur_name[0] == '\0')
+      continue;
+    if (filter && !filter(cur_name))
+      continue;
+    void *mem = &modules[n_modules];
+    // Don't subtract 'cur_beg' from the first entry:
+    // * If a binary is compiled w/o -pie, then the first entry in
+    //   process maps is likely the binary itself (all dynamic libs
+    //   are mapped higher in address space). For such a binary,
+    //   instruction offset in binary coincides with the actual
+    //   instruction address in virtual memory (as code section
+    //   is mapped to a fixed memory range).
+    // * If a binary is compiled with -pie, all the modules are
+    //   mapped high at address space (in particular, higher than
+    //   shadow memory of the tool), so the module can't be the
+    //   first entry.
+    uptr base_address = (i ? cur_beg : 0) - cur_offset;
+    LoadedModule *cur_module = new(mem) LoadedModule(cur_name, base_address);
+    cur_module->addAddressRange(cur_beg, cur_end, prot & kProtectionExecute);
+    n_modules++;
+  }
+  return n_modules;
+}
+
+void GetMemoryProfile(fill_profile_f cb, uptr *stats, uptr stats_size) {
+  char *smaps = 0;
+  uptr smaps_cap = 0;
+  uptr smaps_len = ReadFileToBuffer("/proc/self/smaps",
+      &smaps, &smaps_cap, 64<<20);
+  uptr start = 0;
+  bool file = false;
+  const char *pos = smaps;
+  while (pos < smaps + smaps_len) {
+    if (IsHex(pos[0])) {
+      start = ParseHex(&pos);
+      for (; *pos != '/' && *pos > '\n'; pos++) {}
+      file = *pos == '/';
+    } else if (internal_strncmp(pos, "Rss:", 4) == 0) {
+      while (!IsDecimal(*pos)) pos++;
+      uptr rss = ParseDecimal(&pos) * 1024;
+      cb(start, rss, file, stats, stats_size);
+    }
+    while (*pos++ != '\n') {}
+  }
+  UnmapOrDie(smaps, smaps_cap);
+}
+
+}  // namespace __sanitizer
+
+#endif  // SANITIZER_FREEBSD || SANITIZER_LINUX