JYCache/s3fs/s3fs_util.cpp

593 lines
16 KiB
C++

/*
* s3fs - FUSE-based file system backed by Amazon S3
*
* Copyright(C) 2007 Takeshi Nakatani <ggtakec.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include <cstdio>
#include <cstdlib>
#include <unistd.h>
#include <cerrno>
#include <grp.h>
#include <memory>
#include <pwd.h>
#include <libgen.h>
#include <dirent.h>
#include <sys/stat.h>
#include <sys/utsname.h>
#include <string>
#include <sstream>
#include "s3fs_logger.h"
#include "s3fs_util.h"
#include "string_util.h"
#include "s3fs_help.h"
#include "autolock.h"
//-------------------------------------------------------------------
// Global variables
//-------------------------------------------------------------------
std::string mount_prefix;
static size_t max_password_size;
static size_t max_group_name_length;
//-------------------------------------------------------------------
// Utilities
//-------------------------------------------------------------------
std::string get_realpath(const char *path)
{
std::string realpath = mount_prefix;
realpath += path;
return realpath;
}
void init_sysconf_vars()
{
// SUSv4tc1 says the following about _SC_GETGR_R_SIZE_MAX and
// _SC_GETPW_R_SIZE_MAX:
// Note that sysconf(_SC_GETGR_R_SIZE_MAX) may return -1 if
// there is no hard limit on the size of the buffer needed to
// store all the groups returned.
long res = sysconf(_SC_GETPW_R_SIZE_MAX);
if(0 > res){
if (errno != 0){
S3FS_PRN_WARN("could not get max pw length.");
abort();
}
res = 1024; // default initial length
}
max_password_size = res;
res = sysconf(_SC_GETGR_R_SIZE_MAX);
if(0 > res) {
if (errno != 0) {
S3FS_PRN_ERR("could not get max name length.");
abort();
}
res = 1024; // default initial length
}
max_group_name_length = res;
}
//-------------------------------------------------------------------
// Utility for UID/GID
//-------------------------------------------------------------------
// get user name from uid
std::string get_username(uid_t uid)
{
size_t maxlen = max_password_size;
int result;
struct passwd pwinfo;
struct passwd* ppwinfo = nullptr;
// make buffer
std::unique_ptr<char[]> pbuf(new char[maxlen]);
// get pw information
while(ERANGE == (result = getpwuid_r(uid, &pwinfo, pbuf.get(), maxlen, &ppwinfo))){
maxlen *= 2;
pbuf.reset(new char[maxlen]);
}
if(0 != result){
S3FS_PRN_ERR("could not get pw information(%d).", result);
return "";
}
// check pw
if(nullptr == ppwinfo){
return "";
}
std::string name = SAFESTRPTR(ppwinfo->pw_name);
return name;
}
int is_uid_include_group(uid_t uid, gid_t gid)
{
size_t maxlen = max_group_name_length;
int result;
struct group ginfo;
struct group* pginfo = nullptr;
// make buffer
std::unique_ptr<char[]> pbuf(new char[maxlen]);
// get group information
while(ERANGE == (result = getgrgid_r(gid, &ginfo, pbuf.get(), maxlen, &pginfo))){
maxlen *= 2;
pbuf.reset(new char[maxlen]);
}
if(0 != result){
S3FS_PRN_ERR("could not get group information(%d).", result);
return -result;
}
// check group
if(nullptr == pginfo){
// there is not gid in group.
return -EINVAL;
}
std::string username = get_username(uid);
char** ppgr_mem;
for(ppgr_mem = pginfo->gr_mem; ppgr_mem && *ppgr_mem; ppgr_mem++){
if(username == *ppgr_mem){
// Found username in group.
return 1;
}
}
return 0;
}
//-------------------------------------------------------------------
// Utility for file and directory
//-------------------------------------------------------------------
// [NOTE]
// basename/dirname returns a static variable pointer as the return value.
// Normally this shouldn't be a problem, but in macos10 we found a case
// where dirname didn't receive its return value correctly due to thread
// conflicts.
// To avoid this, exclusive control is performed by mutex.
//
static pthread_mutex_t* pbasename_lock = nullptr;
bool init_basename_lock()
{
if(pbasename_lock){
S3FS_PRN_ERR("already initialized mutex for posix dirname/basename function.");
return false;
}
pbasename_lock = new pthread_mutex_t;
pthread_mutexattr_t attr;
pthread_mutexattr_init(&attr);
#if S3FS_PTHREAD_ERRORCHECK
pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_ERRORCHECK);
#endif
int result;
if(0 != (result = pthread_mutex_init(pbasename_lock, &attr))){
S3FS_PRN_ERR("failed to init pbasename_lock: %d.", result);
delete pbasename_lock;
pbasename_lock = nullptr;
return false;
}
return true;
}
bool destroy_basename_lock()
{
if(!pbasename_lock){
S3FS_PRN_ERR("the mutex for posix dirname/basename function is not initialized.");
return false;
}
int result;
if(0 != (result = pthread_mutex_destroy(pbasename_lock))){
S3FS_PRN_ERR("failed to destroy pbasename_lock: %d", result);
return false;
}
delete pbasename_lock;
pbasename_lock = nullptr;
return true;
}
std::string mydirname(const std::string& path)
{
AutoLock auto_lock(pbasename_lock);
return mydirname(path.c_str());
}
// safe variant of dirname
// dirname clobbers path so let it operate on a tmp copy
std::string mydirname(const char* path)
{
if(!path || '\0' == path[0]){
return "";
}
char *buf = strdup(path);
std::string result = dirname(buf);
free(buf);
return result;
}
std::string mybasename(const std::string& path)
{
AutoLock auto_lock(pbasename_lock);
return mybasename(path.c_str());
}
// safe variant of basename
// basename clobbers path so let it operate on a tmp copy
std::string mybasename(const char* path)
{
if(!path || '\0' == path[0]){
return "";
}
char *buf = strdup(path);
std::string result = basename(buf);
free(buf);
return result;
}
// mkdir --parents
int mkdirp(const std::string& path, mode_t mode)
{
std::string base;
std::string component;
std::istringstream ss(path);
while (getline(ss, component, '/')) {
base += component + "/";
struct stat st;
if(0 == stat(base.c_str(), &st)){
if(!S_ISDIR(st.st_mode)){
return EPERM;
}
}else{
if(0 != mkdir(base.c_str(), mode) && errno != EEXIST){
return errno;
}
}
}
return 0;
}
// get existed directory path
std::string get_exist_directory_path(const std::string& path)
{
std::string existed("/"); // "/" is existed.
std::string base;
std::string component;
std::istringstream ss(path);
while (getline(ss, component, '/')) {
if(base != "/"){
base += "/";
}
base += component;
struct stat st;
if(0 == stat(base.c_str(), &st) && S_ISDIR(st.st_mode)){
existed = base;
}else{
break;
}
}
return existed;
}
bool check_exist_dir_permission(const char* dirpath)
{
if(!dirpath || '\0' == dirpath[0]){
return false;
}
// exists
struct stat st;
if(0 != stat(dirpath, &st)){
if(ENOENT == errno){
// dir does not exist
return true;
}
if(EACCES == errno){
// could not access directory
return false;
}
// something error occurred
return false;
}
// check type
if(!S_ISDIR(st.st_mode)){
// path is not directory
return false;
}
// check permission
uid_t myuid = geteuid();
if(myuid == st.st_uid){
if(S_IRWXU != (st.st_mode & S_IRWXU)){
return false;
}
}else{
if(1 == is_uid_include_group(myuid, st.st_gid)){
if(S_IRWXG != (st.st_mode & S_IRWXG)){
return false;
}
}else{
if(S_IRWXO != (st.st_mode & S_IRWXO)){
return false;
}
}
}
return true;
}
bool delete_files_in_dir(const char* dir, bool is_remove_own)
{
DIR* dp;
struct dirent* dent;
if(nullptr == (dp = opendir(dir))){
S3FS_PRN_ERR("could not open dir(%s) - errno(%d)", dir, errno);
return false;
}
for(dent = readdir(dp); dent; dent = readdir(dp)){
if(0 == strcmp(dent->d_name, "..") || 0 == strcmp(dent->d_name, ".")){
continue;
}
std::string fullpath = dir;
fullpath += "/";
fullpath += dent->d_name;
struct stat st;
if(0 != lstat(fullpath.c_str(), &st)){
S3FS_PRN_ERR("could not get stats of file(%s) - errno(%d)", fullpath.c_str(), errno);
closedir(dp);
return false;
}
if(S_ISDIR(st.st_mode)){
// dir -> Reentrant
if(!delete_files_in_dir(fullpath.c_str(), true)){
S3FS_PRN_ERR("could not remove sub dir(%s) - errno(%d)", fullpath.c_str(), errno);
closedir(dp);
return false;
}
}else{
if(0 != unlink(fullpath.c_str())){
S3FS_PRN_ERR("could not remove file(%s) - errno(%d)", fullpath.c_str(), errno);
closedir(dp);
return false;
}
}
}
closedir(dp);
if(is_remove_own && 0 != rmdir(dir)){
S3FS_PRN_ERR("could not remove dir(%s) - errno(%d)", dir, errno);
return false;
}
return true;
}
//-------------------------------------------------------------------
// Utility for system information
//-------------------------------------------------------------------
bool compare_sysname(const char* target)
{
// [NOTE]
// The buffer size of sysname member in struct utsname is
// OS dependent, but 512 bytes is sufficient for now.
//
static const char* psysname = nullptr;
static char sysname[512];
if(!psysname){
struct utsname sysinfo;
if(0 != uname(&sysinfo)){
S3FS_PRN_ERR("could not initialize system name to internal buffer(errno:%d), thus use \"Linux\".", errno);
strcpy(sysname, "Linux");
}else{
S3FS_PRN_INFO("system name is %s", sysinfo.sysname);
sysname[sizeof(sysname) - 1] = '\0';
strncpy(sysname, sysinfo.sysname, sizeof(sysname) - 1);
}
psysname = &sysname[0];
}
if(!target || 0 != strcmp(psysname, target)){
return false;
}
return true;
}
//-------------------------------------------------------------------
// Utility for print message at launching
//-------------------------------------------------------------------
void print_launch_message(int argc, char** argv)
{
std::string message = short_version();
if(argv){
message += " :";
for(int cnt = 0; cnt < argc; ++cnt){
if(argv[cnt]){
message += " ";
if(0 == cnt){
message += basename(argv[cnt]);
}else{
message += argv[cnt];
}
}
}
}
S3FS_PRN_LAUNCH_INFO("%s", message.c_str());
}
int flock_set(int fd, int type)
{
struct flock lock;
lock.l_whence = SEEK_SET;
lock.l_start = 0;
lock.l_len = 0;
lock.l_type = type;
lock.l_pid = -1;
return fcntl(fd, F_SETLKW, &lock);
}
//
// result: -1 ts1 < ts2
// 0 ts1 == ts2
// 1 ts1 > ts2
//
int compare_timespec(const struct timespec& ts1, const struct timespec& ts2)
{
if(ts1.tv_sec < ts2.tv_sec){
return -1;
}else if(ts1.tv_sec > ts2.tv_sec){
return 1;
}else{
if(ts1.tv_nsec < ts2.tv_nsec){
return -1;
}else if(ts1.tv_nsec > ts2.tv_nsec){
return 1;
}
}
return 0;
}
//
// result: -1 st < ts
// 0 st == ts
// 1 st > ts
//
int compare_timespec(const struct stat& st, stat_time_type type, const struct timespec& ts)
{
struct timespec st_ts;
set_stat_to_timespec(st, type, st_ts);
return compare_timespec(st_ts, ts);
}
void set_timespec_to_stat(struct stat& st, stat_time_type type, const struct timespec& ts)
{
if(stat_time_type::ATIME == type){
#if defined(__APPLE__)
st.st_atime = ts.tv_sec;
st.st_atimespec.tv_nsec = ts.tv_nsec;
#else
st.st_atim.tv_sec = ts.tv_sec;
st.st_atim.tv_nsec = ts.tv_nsec;
#endif
}else if(stat_time_type::MTIME == type){
#if defined(__APPLE__)
st.st_mtime = ts.tv_sec;
st.st_mtimespec.tv_nsec = ts.tv_nsec;
#else
st.st_mtim.tv_sec = ts.tv_sec;
st.st_mtim.tv_nsec = ts.tv_nsec;
#endif
}else if(stat_time_type::CTIME == type){
#if defined(__APPLE__)
st.st_ctime = ts.tv_sec;
st.st_ctimespec.tv_nsec = ts.tv_nsec;
#else
st.st_ctim.tv_sec = ts.tv_sec;
st.st_ctim.tv_nsec = ts.tv_nsec;
#endif
}else{
S3FS_PRN_ERR("unknown type(%d), so skip to set value.", static_cast<int>(type));
}
}
struct timespec* set_stat_to_timespec(const struct stat& st, stat_time_type type, struct timespec& ts)
{
if(stat_time_type::ATIME == type){
#if defined(__APPLE__)
ts.tv_sec = st.st_atime;
ts.tv_nsec = st.st_atimespec.tv_nsec;
#else
ts = st.st_atim;
#endif
}else if(stat_time_type::MTIME == type){
#if defined(__APPLE__)
ts.tv_sec = st.st_mtime;
ts.tv_nsec = st.st_mtimespec.tv_nsec;
#else
ts = st.st_mtim;
#endif
}else if(stat_time_type::CTIME == type){
#if defined(__APPLE__)
ts.tv_sec = st.st_ctime;
ts.tv_nsec = st.st_ctimespec.tv_nsec;
#else
ts = st.st_ctim;
#endif
}else{
S3FS_PRN_ERR("unknown type(%d), so use 0 as timespec.", static_cast<int>(type));
ts.tv_sec = 0;
ts.tv_nsec = 0;
}
return &ts;
}
std::string str_stat_time(const struct stat& st, stat_time_type type)
{
struct timespec ts;
return str(*set_stat_to_timespec(st, type, ts));
}
struct timespec* s3fs_realtime(struct timespec& ts)
{
if(-1 == clock_gettime(static_cast<clockid_t>(CLOCK_REALTIME), &ts)){
S3FS_PRN_WARN("failed to clock_gettime by errno(%d)", errno);
ts.tv_sec = time(nullptr);
ts.tv_nsec = 0;
}
return &ts;
}
std::string s3fs_str_realtime()
{
struct timespec ts;
return str(*s3fs_realtime(ts));
}
int s3fs_fclose(FILE* fp)
{
if(fp == nullptr){
return 0;
}
return fclose(fp);
}
/*
* Local variables:
* tab-width: 4
* c-basic-offset: 4
* End:
* vim600: expandtab sw=4 ts=4 fdm=marker
* vim<600: expandtab sw=4 ts=4
*/