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/*
* Copyright 2008, The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "utility.h"
#include <errno.h>
#include <signal.h>
#include <string.h>
#include <unistd.h>
#include <sys/ptrace.h>
#include <sys/wait.h>
#include <backtrace/Backtrace.h>
#include <log/logd.h>
const int sleep_time_usec = 50000; // 0.05 seconds
const int max_total_sleep_usec = 10000000; // 10 seconds
static int write_to_am(int fd, const char* buf, int len) {
int to_write = len;
while (to_write > 0) {
int written = TEMP_FAILURE_RETRY(write(fd, buf + len - to_write, to_write));
if (written < 0) {
// hard failure
LOG("AM write failure (%d / %s)\n", errno, strerror(errno));
return -1;
}
to_write -= written;
}
return len;
}
void _LOG(log_t* log, int scopeFlags, const char* fmt, ...) {
bool want_tfd_write = log && log->tfd >= 0;
bool want_log_write = IS_AT_FAULT(scopeFlags) && (!log || !log->quiet);
bool want_amfd_write = IS_AT_FAULT(scopeFlags) && !IS_SENSITIVE(scopeFlags) && log && log->amfd >= 0;
char buf[512];
va_list ap;
va_start(ap, fmt);
vsnprintf(buf, sizeof(buf), fmt, ap);
va_end(ap);
size_t len = strlen(buf);
if (len <= 0) {
return;
}
if (want_tfd_write) {
TEMP_FAILURE_RETRY(write(log->tfd, buf, len));
}
if (want_log_write) {
__android_log_write(ANDROID_LOG_INFO, "DEBUG", buf);
if (want_amfd_write) {
int written = write_to_am(log->amfd, buf, len);
if (written <= 0) {
// timeout or other failure on write; stop informing the activity manager
log->amfd = -1;
}
}
}
}
int wait_for_signal(pid_t tid, int* total_sleep_time_usec) {
for (;;) {
int status;
pid_t n = waitpid(tid, &status, __WALL | WNOHANG);
if (n < 0) {
if (errno == EAGAIN)
continue;
LOG("waitpid failed: %s\n", strerror(errno));
return -1;
} else if (n > 0) {
XLOG("waitpid: n=%d status=%08x\n", n, status);
if (WIFSTOPPED(status)) {
return WSTOPSIG(status);
} else {
LOG("unexpected waitpid response: n=%d, status=%08x\n", n, status);
return -1;
}
}
if (*total_sleep_time_usec > max_total_sleep_usec) {
LOG("timed out waiting for tid=%d to die\n", tid);
return -1;
}
// not ready yet
XLOG("not ready yet\n");
usleep(sleep_time_usec);
*total_sleep_time_usec += sleep_time_usec;
}
}
void wait_for_stop(pid_t tid, int* total_sleep_time_usec) {
siginfo_t si;
while (TEMP_FAILURE_RETRY(ptrace(PTRACE_GETSIGINFO, tid, 0, &si)) < 0 && errno == ESRCH) {
if (*total_sleep_time_usec > max_total_sleep_usec) {
LOG("timed out waiting for tid=%d to stop\n", tid);
break;
}
usleep(sleep_time_usec);
*total_sleep_time_usec += sleep_time_usec;
}
}
#if defined (__mips__)
#define DUMP_MEMORY_AS_ASCII 1
#else
#define DUMP_MEMORY_AS_ASCII 0
#endif
void dump_memory(log_t* log, pid_t tid, uintptr_t addr, int scope_flags) {
char code_buffer[64];
char ascii_buffer[32];
uintptr_t p, end;
p = addr & ~(sizeof(long) - 1);
/* Dump 32 bytes before addr */
p -= 32;
if (p > addr) {
/* catch underflow */
p = 0;
}
/* Dump 256 bytes */
end = p + 256;
/* catch overflow; 'end - p' has to be multiples of 16 */
while (end < p) {
end -= 16;
}
/* Dump the code around PC as:
* addr contents ascii
* 0000000000008d34 ef000000e8bd0090 e1b00000512fff1e ............../Q
* 0000000000008d44 ea00b1f9e92d0090 e3a070fcef000000 ......-..p......
* On 32-bit machines, there are still 16 bytes per line but addresses and
* words are of course presented differently.
*/
while (p < end) {
char* asc_out = ascii_buffer;
int len = snprintf(code_buffer, sizeof(code_buffer), "%" PRIPTR " ", p);
for (size_t i = 0; i < 16/sizeof(long); i++) {
long data = ptrace(PTRACE_PEEKTEXT, tid, (void*)p, NULL);
if (data == -1 && errno != 0) {
// ptrace failed, probably because we're dumping memory in an
// unmapped or inaccessible page.
#ifdef __LP64__
len += sprintf(code_buffer + len, "---------------- ");
#else
len += sprintf(code_buffer + len, "-------- ");
#endif
} else {
len += sprintf(code_buffer + len, "%" PRIPTR " ",
static_cast<uintptr_t>(data));
}
#if DUMP_MEMORY_AS_ASCII
for (size_t j = 0; j < sizeof(long); j++) {
/*
* Our isprint() allows high-ASCII characters that display
* differently (often badly) in different viewers, so we
* just use a simpler test.
*/
char val = (data >> (j*8)) & 0xff;
if (val >= 0x20 && val < 0x7f) {
*asc_out++ = val;
} else {
*asc_out++ = '.';
}
}
#endif
p += sizeof(long);
}
*asc_out = '\0';
_LOG(log, scope_flags, " %s %s\n", code_buffer, ascii_buffer);
}
}
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