platform_system_core/liblog/local_logger.c

550 lines
16 KiB
C

/*
* Copyright (C) 2017 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 <errno.h>
#include <fcntl.h>
#include <pthread.h>
#if !defined(__MINGW32__)
#include <pwd.h>
#endif
#include <log/uio.h>
#include <sched.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <cutils/list.h> /* template, no library dependency */
#include <log/log_transport.h>
#include <private/android_filesystem_config.h>
#include <private/android_logger.h>
#include <system/thread_defs.h>
#include "config_read.h"
#include "config_write.h"
#include "log_portability.h"
#include "logger.h"
static const char baseServiceName[] = "android.logd";
static int writeToLocalInit();
static int writeToLocalAvailable(log_id_t logId);
static void writeToLocalReset();
static int writeToLocalWrite(log_id_t logId, struct timespec* ts,
struct iovec* vec, size_t nr);
LIBLOG_HIDDEN struct android_log_transport_write localLoggerWrite = {
.node = { &localLoggerWrite.node, &localLoggerWrite.node },
.context.priv = NULL,
.name = "local",
.available = writeToLocalAvailable,
.open = writeToLocalInit,
.close = writeToLocalReset,
.write = writeToLocalWrite,
};
static int writeToLocalVersion(struct android_log_logger* logger,
struct android_log_transport_context* transp);
static int writeToLocalRead(struct android_log_logger_list* logger_list,
struct android_log_transport_context* transp,
struct log_msg* log_msg);
static int writeToLocalPoll(struct android_log_logger_list* logger_list,
struct android_log_transport_context* transp);
static void writeToLocalClose(struct android_log_logger_list* logger_list,
struct android_log_transport_context* transp);
static int writeToLocalClear(struct android_log_logger* logger,
struct android_log_transport_context* transp);
static ssize_t writeToLocalGetSize(struct android_log_logger* logger,
struct android_log_transport_context* transp);
static ssize_t writeToLocalSetSize(
struct android_log_logger* logger,
struct android_log_transport_context* transp __unused, size_t size);
static ssize_t writeToLocalGetReadbleSize(
struct android_log_logger* logger,
struct android_log_transport_context* transp);
struct android_log_transport_read localLoggerRead = {
.node = { &localLoggerRead.node, &localLoggerRead.node },
.name = "local",
.available = writeToLocalAvailable,
.version = writeToLocalVersion,
.read = writeToLocalRead,
.poll = writeToLocalPoll,
.close = writeToLocalClose,
.clear = writeToLocalClear,
.getSize = writeToLocalGetSize,
.setSize = writeToLocalSetSize,
.getReadableSize = writeToLocalGetReadbleSize,
.getPrune = NULL,
.setPrune = NULL,
.getStats = NULL,
};
struct LogBufferElement {
struct listnode node;
log_id_t logId;
pid_t tid;
log_time timestamp;
unsigned short len;
char msg[];
};
static const size_t MAX_SIZE_DEFAULT = 32768;
/*
* Number of log buffers we support with the following assumption:
* . . .
* LOG_ID_SECURITY = 5, // security logs go to the system logs only
* LOG_ID_KERNEL = 6, // place last, third-parties can not use it
* LOG_ID_MAX
* } log_id_t;
*
* Confirm the following should <log/log_id.h> be adjusted in the future.
*/
#define NUMBER_OF_LOG_BUFFERS \
((LOG_ID_SECURITY == (LOG_ID_MAX - 2)) ? LOG_ID_SECURITY : LOG_ID_KERNEL)
#define BLOCK_LOG_BUFFERS(id) \
(((id) == LOG_ID_SECURITY) || ((id) == LOG_ID_KERNEL))
static struct LogBuffer {
struct listnode head;
pthread_rwlock_t listLock;
char* serviceName; /* Also indicates ready by having a value */
/* Order and proximity important for memset */
size_t number[NUMBER_OF_LOG_BUFFERS]; /* clear memset */
size_t size[NUMBER_OF_LOG_BUFFERS]; /* clear memset */
size_t totalSize[NUMBER_OF_LOG_BUFFERS]; /* init memset */
size_t maxSize[NUMBER_OF_LOG_BUFFERS]; /* init MAX_SIZE_DEFAULT */
struct listnode* last[NUMBER_OF_LOG_BUFFERS]; /* init &head */
} logbuf = {
.head = { &logbuf.head, &logbuf.head }, .listLock = PTHREAD_RWLOCK_INITIALIZER,
};
static void LogBufferInit(struct LogBuffer* log) {
size_t i;
pthread_rwlock_wrlock(&log->listLock);
list_init(&log->head);
memset(log->number, 0,
sizeof(log->number) + sizeof(log->size) + sizeof(log->totalSize));
for (i = 0; i < NUMBER_OF_LOG_BUFFERS; ++i) {
log->maxSize[i] = MAX_SIZE_DEFAULT;
log->last[i] = &log->head;
}
#ifdef __BIONIC__
asprintf(&log->serviceName, "%s@%d:%d", baseServiceName, __android_log_uid(),
getpid());
#else
char buffer[sizeof(baseServiceName) + 1 + 5 + 1 + 5 + 8];
snprintf(buffer, sizeof(buffer), "%s@%d:%d", baseServiceName,
__android_log_uid(), getpid());
log->serviceName = strdup(buffer);
#endif
pthread_rwlock_unlock(&log->listLock);
}
static void LogBufferClear(struct LogBuffer* log) {
size_t i;
struct listnode* node;
pthread_rwlock_wrlock(&log->listLock);
memset(log->number, 0, sizeof(log->number) + sizeof(log->size));
for (i = 0; i < NUMBER_OF_LOG_BUFFERS; ++i) {
log->last[i] = &log->head;
}
while ((node = list_head(&log->head)) != &log->head) {
struct LogBufferElement* element;
element = node_to_item(node, struct LogBufferElement, node);
list_remove(node);
free(element);
}
pthread_rwlock_unlock(&log->listLock);
}
static inline void LogBufferFree(struct LogBuffer* log) {
pthread_rwlock_wrlock(&log->listLock);
free(log->serviceName);
log->serviceName = NULL;
pthread_rwlock_unlock(&log->listLock);
LogBufferClear(log);
}
static int LogBufferLog(struct LogBuffer* log,
struct LogBufferElement* element) {
log_id_t logId = element->logId;
pthread_rwlock_wrlock(&log->listLock);
log->number[logId]++;
log->size[logId] += element->len;
log->totalSize[logId] += element->len;
/* prune entry(s) until enough space is available */
if (log->last[logId] == &log->head) {
log->last[logId] = list_tail(&log->head);
}
while (log->size[logId] > log->maxSize[logId]) {
struct listnode* node = log->last[logId];
struct LogBufferElement* e;
struct android_log_logger_list* logger_list;
e = node_to_item(node, struct LogBufferElement, node);
log->number[logId]--;
log->size[logId] -= e->len;
logger_list_rdlock();
logger_list_for_each(logger_list) {
struct android_log_transport_context* transp;
transport_context_for_each(transp, logger_list) {
if ((transp->transport == &localLoggerRead) &&
(transp->context.node == node)) {
if (node == &log->head) {
transp->context.node = &log->head;
} else {
transp->context.node = node->next;
}
}
}
}
logger_list_unlock();
if (node != &log->head) {
log->last[logId] = node->prev;
}
list_remove(node);
free(e);
}
/* add entry to list */
list_add_head(&log->head, &element->node);
/* ToDo: wake up all readers */
pthread_rwlock_unlock(&log->listLock);
return element->len;
}
/*
* return zero if permitted to log directly to logd,
* return 1 if binder server started and
* return negative error number if failed to start binder server.
*/
static int writeToLocalInit() {
pthread_attr_t attr;
struct LogBuffer* log;
if (writeToLocalAvailable(LOG_ID_MAIN) < 0) {
return -EPERM;
}
log = &logbuf;
if (!log->serviceName) {
LogBufferInit(log);
}
if (!log->serviceName) {
LogBufferFree(log);
return -ENOMEM;
}
return EPERM; /* successful local-only logging */
}
static void writeToLocalReset() {
LogBufferFree(&logbuf);
}
static int writeToLocalAvailable(log_id_t logId) {
#if !defined(__MINGW32__)
uid_t uid;
#endif
if ((logId >= NUMBER_OF_LOG_BUFFERS) || BLOCK_LOG_BUFFERS(logId)) {
return -EINVAL;
}
/* Android hard coded permitted, system goes to logd */
#if !defined(__MINGW32__)
if (__android_log_transport == LOGGER_DEFAULT) {
uid = __android_log_uid();
if ((uid < AID_APP) && (getpwuid(uid) != NULL)) {
return -EPERM;
}
}
#endif
/* ToDo: Ask package manager for LOGD permissions */
/* Assume we do _not_ have permissions to go to LOGD, so must go local */
return 0;
}
static int writeToLocalWrite(log_id_t logId, struct timespec* ts,
struct iovec* vec, size_t nr) {
size_t len, i;
struct LogBufferElement* element;
if ((logId >= NUMBER_OF_LOG_BUFFERS) || BLOCK_LOG_BUFFERS(logId)) {
return -EINVAL;
}
len = 0;
for (i = 0; i < nr; ++i) {
len += vec[i].iov_len;
}
if (len > LOGGER_ENTRY_MAX_PAYLOAD) {
len = LOGGER_ENTRY_MAX_PAYLOAD;
}
element = (struct LogBufferElement*)calloc(
1, sizeof(struct LogBufferElement) + len + 1);
if (!element) {
return errno ? -errno : -ENOMEM;
}
element->timestamp.tv_sec = ts->tv_sec;
element->timestamp.tv_nsec = ts->tv_nsec;
#ifdef __BIONIC__
element->tid = gettid();
#else
element->tid = getpid();
#endif
element->logId = logId;
element->len = len;
char* cp = element->msg;
for (i = 0; i < nr; ++i) {
size_t iov_len = vec[i].iov_len;
if (iov_len > len) {
iov_len = len;
}
memcpy(cp, vec[i].iov_base, iov_len);
len -= iov_len;
if (len == 0) {
break;
}
cp += iov_len;
}
return LogBufferLog(&logbuf, element);
}
static int writeToLocalVersion(struct android_log_logger* logger __unused,
struct android_log_transport_context* transp
__unused) {
return 3;
}
/* within reader lock, serviceName already validated */
static struct listnode* writeToLocalNode(
struct android_log_logger_list* logger_list,
struct android_log_transport_context* transp) {
struct listnode* node;
unsigned logMask;
unsigned int tail;
node = transp->context.node;
if (node) {
return node;
}
if (!logger_list->tail) {
return transp->context.node = &logbuf.head;
}
logMask = transp->logMask;
tail = logger_list->tail;
for (node = list_head(&logbuf.head); node != &logbuf.head; node = node->next) {
struct LogBufferElement* element;
log_id_t logId;
element = node_to_item(node, struct LogBufferElement, node);
logId = element->logId;
if ((logMask & (1 << logId)) && !--tail) {
node = node->next;
break;
}
}
return transp->context.node = node;
}
static int writeToLocalRead(struct android_log_logger_list* logger_list,
struct android_log_transport_context* transp,
struct log_msg* log_msg) {
int ret;
struct listnode* node;
unsigned logMask;
pthread_rwlock_rdlock(&logbuf.listLock);
if (!logbuf.serviceName) {
pthread_rwlock_unlock(&logbuf.listLock);
return (logger_list->mode & ANDROID_LOG_NONBLOCK) ? -ENODEV : 0;
}
logMask = transp->logMask;
node = writeToLocalNode(logger_list, transp);
ret = 0;
while (node != list_head(&logbuf.head)) {
struct LogBufferElement* element;
log_id_t logId;
node = node->prev;
element = node_to_item(node, struct LogBufferElement, node);
logId = element->logId;
if (logMask & (1 << logId)) {
ret = log_msg->entry_v3.len = element->len;
log_msg->entry_v3.hdr_size = sizeof(log_msg->entry_v3);
log_msg->entry_v3.pid = getpid();
log_msg->entry_v3.tid = element->tid;
log_msg->entry_v3.sec = element->timestamp.tv_sec;
log_msg->entry_v3.nsec = element->timestamp.tv_nsec;
log_msg->entry_v3.lid = logId;
memcpy(log_msg->entry_v3.msg, element->msg, ret);
ret += log_msg->entry_v3.hdr_size;
break;
}
}
transp->context.node = node;
/* ToDo: if blocking, and no entry, put reader to sleep */
pthread_rwlock_unlock(&logbuf.listLock);
return ret;
}
static int writeToLocalPoll(struct android_log_logger_list* logger_list,
struct android_log_transport_context* transp) {
int ret = (logger_list->mode & ANDROID_LOG_NONBLOCK) ? -ENODEV : 0;
pthread_rwlock_rdlock(&logbuf.listLock);
if (logbuf.serviceName) {
unsigned logMask = transp->logMask;
struct listnode* node = writeToLocalNode(logger_list, transp);
ret = (node != list_head(&logbuf.head));
if (ret) {
do {
ret = !!(logMask &
(1 << (node_to_item(node->prev, struct LogBufferElement, node))
->logId));
} while (!ret && ((node = node->prev) != list_head(&logbuf.head)));
}
transp->context.node = node;
}
pthread_rwlock_unlock(&logbuf.listLock);
return ret;
}
static void writeToLocalClose(struct android_log_logger_list* logger_list
__unused,
struct android_log_transport_context* transp) {
pthread_rwlock_wrlock(&logbuf.listLock);
transp->context.node = list_head(&logbuf.head);
pthread_rwlock_unlock(&logbuf.listLock);
}
static int writeToLocalClear(struct android_log_logger* logger,
struct android_log_transport_context* unused
__unused) {
log_id_t logId = logger->logId;
struct listnode *node, *n;
if ((logId >= NUMBER_OF_LOG_BUFFERS) || BLOCK_LOG_BUFFERS(logId)) {
return -EINVAL;
}
pthread_rwlock_wrlock(&logbuf.listLock);
logbuf.number[logId] = 0;
logbuf.last[logId] = &logbuf.head;
list_for_each_safe(node, n, &logbuf.head) {
struct LogBufferElement* element;
element = node_to_item(node, struct LogBufferElement, node);
if (logId == element->logId) {
struct android_log_logger_list* logger_list;
logger_list_rdlock();
logger_list_for_each(logger_list) {
struct android_log_transport_context* transp;
transport_context_for_each(transp, logger_list) {
if ((transp->transport == &localLoggerRead) &&
(transp->context.node == node)) {
transp->context.node = node->next;
}
}
}
logger_list_unlock();
list_remove(node);
free(element);
}
}
pthread_rwlock_unlock(&logbuf.listLock);
return 0;
}
static ssize_t writeToLocalGetSize(struct android_log_logger* logger,
struct android_log_transport_context* transp
__unused) {
ssize_t ret = -EINVAL;
log_id_t logId = logger->logId;
if ((logId < NUMBER_OF_LOG_BUFFERS) && !BLOCK_LOG_BUFFERS(logId)) {
pthread_rwlock_rdlock(&logbuf.listLock);
ret = logbuf.maxSize[logId];
pthread_rwlock_unlock(&logbuf.listLock);
}
return ret;
}
static ssize_t writeToLocalSetSize(
struct android_log_logger* logger,
struct android_log_transport_context* transp __unused, size_t size) {
ssize_t ret = -EINVAL;
if ((size > LOGGER_ENTRY_MAX_LEN) || (size < (4 * 1024 * 1024))) {
log_id_t logId = logger->logId;
if ((logId < NUMBER_OF_LOG_BUFFERS) || !BLOCK_LOG_BUFFERS(logId)) {
pthread_rwlock_wrlock(&logbuf.listLock);
ret = logbuf.maxSize[logId] = size;
pthread_rwlock_unlock(&logbuf.listLock);
}
}
return ret;
}
static ssize_t writeToLocalGetReadbleSize(
struct android_log_logger* logger,
struct android_log_transport_context* transp __unused) {
ssize_t ret = -EINVAL;
log_id_t logId = logger->logId;
if ((logId < NUMBER_OF_LOG_BUFFERS) && !BLOCK_LOG_BUFFERS(logId)) {
pthread_rwlock_rdlock(&logbuf.listLock);
ret = logbuf.serviceName ? (ssize_t)logbuf.size[logId] : -EBADF;
pthread_rwlock_unlock(&logbuf.listLock);
}
return ret;
}