llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_common.cc

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//===-- sanitizer_common.cc -----------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file is shared between AddressSanitizer and ThreadSanitizer
// run-time libraries.
//===----------------------------------------------------------------------===//
#include "sanitizer_common.h"
#include "sanitizer_libc.h"
namespace __sanitizer {
uptr GetPageSizeCached() {
static uptr PageSize;
if (!PageSize)
PageSize = GetPageSize();
return PageSize;
}
static bool log_to_file = false; // Set to true by __sanitizer_set_report_path
// By default, dump to stderr. If |log_to_file| is true and |report_fd_pid|
// isn't equal to the current PID, try to obtain file descriptor by opening
// file "report_path_prefix.<PID>".
static fd_t report_fd = kStderrFd;
static char report_path_prefix[4096]; // Set via __sanitizer_set_report_path.
// PID of process that opened |report_fd|. If a fork() occurs, the PID of the
// child thread will be different from |report_fd_pid|.
static int report_fd_pid = 0;
static void (*DieCallback)(void);
void SetDieCallback(void (*callback)(void)) {
DieCallback = callback;
}
void NORETURN Die() {
if (DieCallback) {
DieCallback();
}
Exit(1);
}
static CheckFailedCallbackType CheckFailedCallback;
void SetCheckFailedCallback(CheckFailedCallbackType callback) {
CheckFailedCallback = callback;
}
void NORETURN CheckFailed(const char *file, int line, const char *cond,
u64 v1, u64 v2) {
if (CheckFailedCallback) {
CheckFailedCallback(file, line, cond, v1, v2);
}
Report("Sanitizer CHECK failed: %s:%d %s (%lld, %lld)\n", file, line, cond,
v1, v2);
Die();
}
static void MaybeOpenReportFile() {
if (!log_to_file || (report_fd_pid == GetPid())) return;
char report_path_full[4096];
internal_snprintf(report_path_full, sizeof(report_path_full),
"%s.%d", report_path_prefix, GetPid());
fd_t fd = internal_open(report_path_full, true);
if (fd == kInvalidFd) {
report_fd = kStderrFd;
log_to_file = false;
Report("ERROR: Can't open file: %s\n", report_path_full);
Die();
}
if (report_fd != kInvalidFd) {
// We're in the child. Close the parent's log.
internal_close(report_fd);
}
report_fd = fd;
report_fd_pid = GetPid();
}
bool PrintsToTty() {
MaybeOpenReportFile();
return internal_isatty(report_fd);
}
void RawWrite(const char *buffer) {
static const char *kRawWriteError = "RawWrite can't output requested buffer!";
uptr length = (uptr)internal_strlen(buffer);
MaybeOpenReportFile();
if (length != internal_write(report_fd, buffer, length)) {
internal_write(report_fd, kRawWriteError, internal_strlen(kRawWriteError));
Die();
}
}
uptr ReadFileToBuffer(const char *file_name, char **buff,
uptr *buff_size, uptr max_len) {
uptr PageSize = GetPageSizeCached();
uptr kMinFileLen = PageSize;
uptr read_len = 0;
*buff = 0;
*buff_size = 0;
// The files we usually open are not seekable, so try different buffer sizes.
for (uptr size = kMinFileLen; size <= max_len; size *= 2) {
fd_t fd = internal_open(file_name, /*write*/ false);
if (fd == kInvalidFd) return 0;
UnmapOrDie(*buff, *buff_size);
*buff = (char*)MmapOrDie(size, __FUNCTION__);
*buff_size = size;
// Read up to one page at a time.
read_len = 0;
bool reached_eof = false;
while (read_len + PageSize <= size) {
uptr just_read = internal_read(fd, *buff + read_len, PageSize);
if (just_read == 0) {
reached_eof = true;
break;
}
read_len += just_read;
}
internal_close(fd);
if (reached_eof) // We've read the whole file.
break;
}
return read_len;
}
// We don't want to use std::sort to avoid including <algorithm>, as
// we may end up with two implementation of std::sort - one in instrumented
// code, and the other in runtime.
// qsort() from stdlib won't work as it calls malloc(), which results
// in deadlock in ASan allocator.
// We re-implement in-place sorting w/o recursion as straightforward heapsort.
void SortArray(uptr *array, uptr size) {
if (size < 2)
return;
// Stage 1: insert elements to the heap.
for (uptr i = 1; i < size; i++) {
uptr j, p;
for (j = i; j > 0; j = p) {
p = (j - 1) / 2;
if (array[j] > array[p])
Swap(array[j], array[p]);
else
break;
}
}
// Stage 2: swap largest element with the last one,
// and sink the new top.
for (uptr i = size - 1; i > 0; i--) {
Swap(array[0], array[i]);
uptr j, max_ind;
for (j = 0; j < i; j = max_ind) {
uptr left = 2 * j + 1;
uptr right = 2 * j + 2;
max_ind = j;
if (left < i && array[left] > array[max_ind])
max_ind = left;
if (right < i && array[right] > array[max_ind])
max_ind = right;
if (max_ind != j)
Swap(array[j], array[max_ind]);
else
break;
}
}
}
// We want to map a chunk of address space aligned to 'alignment'.
// We do it by maping a bit more and then unmaping redundant pieces.
// We probably can do it with fewer syscalls in some OS-dependent way.
void *MmapAlignedOrDie(uptr size, uptr alignment, const char *mem_type) {
// uptr PageSize = GetPageSizeCached();
CHECK(IsPowerOfTwo(size));
CHECK(IsPowerOfTwo(alignment));
uptr map_size = size + alignment;
uptr map_res = (uptr)MmapOrDie(map_size, mem_type);
uptr map_end = map_res + map_size;
uptr res = map_res;
if (res & (alignment - 1)) // Not aligned.
res = (map_res + alignment) & ~(alignment - 1);
uptr end = res + size;
if (res != map_res)
UnmapOrDie((void*)map_res, res - map_res);
if (end != map_end)
UnmapOrDie((void*)end, map_end - end);
return (void*)res;
}
} // namespace __sanitizer
using namespace __sanitizer; // NOLINT
extern "C" {
void __sanitizer_set_report_path(const char *path) {
if (!path) return;
uptr len = internal_strlen(path);
if (len > sizeof(report_path_prefix) - 100) {
Report("ERROR: Path is too long: %c%c%c%c%c%c%c%c...\n",
path[0], path[1], path[2], path[3],
path[4], path[5], path[6], path[7]);
Die();
}
internal_strncpy(report_path_prefix, path, sizeof(report_path_prefix));
report_path_prefix[len] = '\0';
report_fd = kInvalidFd;
log_to_file = true;
}
void __sanitizer_set_report_fd(int fd) {
if (report_fd != kStdoutFd &&
report_fd != kStderrFd &&
report_fd != kInvalidFd)
internal_close(report_fd);
report_fd = fd;
}
void NOINLINE __sanitizer_sandbox_on_notify(void *reserved) {
(void)reserved;
PrepareForSandboxing();
}
} // extern "C"