Retro68/gcc/libsanitizer/sanitizer_common/sanitizer_procmaps_common.cc
2015-08-28 17:33:40 +02:00

177 lines
5.4 KiB
C++

//===-- 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