Change the way some maps are printed.

Before, an anonymous map wound up printing the pc as relative.
Unfortunately, this meant that it was impossible to tell the actual
pc. The new code prints the map name as <anonymous:map_start> and
still prints the pc as relative.

In addition, add the start of the map for map names that begin with a
'[' character.

Bug: 25844836
Change-Id: Ie0b6149dde258fe13f0e5a3e5739d85374512f4b
This commit is contained in:
Christopher Ferris 2015-11-30 13:36:08 -08:00
parent e08e4656db
commit da750a79c9
2 changed files with 33 additions and 10 deletions

View File

@ -93,16 +93,26 @@ std::string Backtrace::FormatFrameData(size_t frame_num) {
}
std::string Backtrace::FormatFrameData(const backtrace_frame_data_t* frame) {
const char* map_name;
if (BacktraceMap::IsValid(frame->map) && !frame->map.name.empty()) {
map_name = frame->map.name.c_str();
uintptr_t relative_pc;
std::string map_name;
if (BacktraceMap::IsValid(frame->map)) {
relative_pc = BacktraceMap::GetRelativePc(frame->map, frame->pc);
if (!frame->map.name.empty()) {
map_name = frame->map.name.c_str();
if (map_name[0] == '[' && map_name[map_name.size() - 1] == ']') {
map_name.resize(map_name.size() - 1);
map_name += StringPrintf(":%" PRIPTR "]", frame->map.start);
}
} else {
map_name = StringPrintf("<anonymous:%" PRIPTR ">", frame->map.start);
}
} else {
map_name = "<unknown>";
relative_pc = frame->pc;
}
uintptr_t relative_pc = BacktraceMap::GetRelativePc(frame->map, frame->pc);
std::string line(StringPrintf("#%02zu pc %" PRIPTR " %s", frame->num, relative_pc, map_name));
std::string line(StringPrintf("#%02zu pc %" PRIPTR " ", frame->num, relative_pc));
line += map_name;
// Special handling for non-zero offset maps, we need to print that
// information.
if (frame->map.offset != 0) {

View File

@ -775,16 +775,29 @@ TEST(libbacktrace, format_test) {
backtrace->FormatFrameData(&frame));
// Check map name empty, but exists.
frame.map.start = 1;
frame.map.end = 1;
frame.pc = 0xb0020;
frame.map.start = 0xb0000;
frame.map.end = 0xbffff;
frame.map.load_base = 0;
#if defined(__LP64__)
EXPECT_EQ("#01 pc 0000000000000001 <unknown>",
EXPECT_EQ("#01 pc 0000000000000020 <anonymous:00000000000b0000>",
#else
EXPECT_EQ("#01 pc 00000001 <unknown>",
EXPECT_EQ("#01 pc 00000020 <anonymous:000b0000>",
#endif
backtrace->FormatFrameData(&frame));
// Check map name begins with a [.
frame.pc = 0xc0020;
frame.map.start = 0xc0000;
frame.map.end = 0xcffff;
frame.map.load_base = 0;
frame.map.name = "[anon:thread signal stack]";
#if defined(__LP64__)
EXPECT_EQ("#01 pc 0000000000000020 [anon:thread signal stack:00000000000c0000]",
#else
EXPECT_EQ("#01 pc 00000020 [anon:thread signal stack:000c0000]",
#endif
backtrace->FormatFrameData(&frame));
// Check relative pc is set and map name is set.
frame.pc = 0x12345679;