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#ifdef USE_PCH
#include "pch.h"
#else
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/ipc.h>
#include <sys/sem.h>
#include <errno.h>
#include <iostream>
#include <fstream>
#include <cassert>
#include "sitecing/sitecing_util.h"
#endif
namespace sitecing {
/*
* XXX: all of these utilities could be sheerly optimized.
*/
string strip_prefix(const string& str,const string& prefix) {
if( (str.length()<prefix.length()) || str.compare(0,prefix.length(),prefix))
throw utility_no_prefix(CODEPOINT,"no such prefix");
return str.substr(prefix.length());
}
string strip_suffix(const string& str,const string& suffix) {
if( (str.length()<suffix.length()) || str.compare(str.length()-suffix.length(),suffix.length(),suffix))
throw utility_no_suffix(CODEPOINT,"no such suffix");
return str.substr(0,str.length()-suffix.length());
}
void file_lock::lock(const string& f) {
unlock();
fd = open(f.c_str(),O_CREAT|O_RDWR,S_IRUSR|S_IWUSR);
if(fd<0)
throw konforka::exception(CODEPOINT,"failed to open/create lockfile");
try {
lock();
}catch(konforka::exception& ke) {
ke.see(CODEPOINT);
close(fd); fd=-1;
throw;
}catch(...) {
close(fd); fd=-1;
throw;
}
}
void file_lock::lock() {
assert(fd>=0);
struct flock fl;
fl.l_type = F_WRLCK;
fl.l_whence=SEEK_SET;
fl.l_start=fl.l_len=0;
for(int tries=3;tries;tries--) {
if(!fcntl(fd,F_SETLK,&fl))
return;
sleep(8);
}
throw konforka::exception(CODEPOINT,"failed to obtain file lock");
}
void file_lock::unlock() {
if(fd<0)
return;
struct flock fl;
fl.l_type = F_UNLCK;
fl.l_whence=SEEK_SET;
fl.l_start=fl.l_len=0;
int rv = fcntl(fd,F_SETLK,&fl);
close(fd);
fd=-1;
if(rv)
throw konforka::exception(CODEPOINT,"failed to release file lock");
}
void pid_file::set(const string& f,bool u) {
ofstream of(f.c_str(),ios::trunc);
if(!of)
throw konforka::exception(CODEPOINT,"failed to open file for writing pid");
of << getpid() << endl;
of.close();
file_name = f;
unlink_pid = u;
}
void pid_file::unlink() {
if(!unlink_pid)
return;
::unlink(file_name.c_str());
}
void semaphore::init() {
deinit();
semid = semget(IPC_PRIVATE,1,IPC_CREAT|0600);
if(semid<0)
throw konforka::exception(CODEPOINT,"failed to semget()");
if(semctl(semid,0,SETVAL,1))
throw konforka::exception(CODEPOINT,"failed to semctl()");
}
void semaphore::deinit() {
if(semid<0)
return;
semctl(semid,0,IPC_RMID,0);
}
void semaphore::on() {
assert(semid>=0);
struct sembuf sb;
sb.sem_num=0;
sb.sem_op=-1;
sb.sem_flg = SEM_UNDO;
while(semop(semid,&sb,1)<0) {
if(errno!=EINTR)
throw konforka::exception(CODEPOINT,"failed to semop()");
}
}
void semaphore::off() {
assert(semid>=0);
struct sembuf sb;
sb.sem_num=0;
sb.sem_op=1;
sb.sem_flg = SEM_UNDO;
while(semop(semid,&sb,1)<0) {
if(errno!=EINTR)
throw konforka::exception(CODEPOINT,"failed to semop()");
}
}
void semaphore_lock::lock() {
assert(sem);
if(locked)
return;
sem->on();
locked = true;
}
void semaphore_lock::unlock() {
if(!sem)
return;
if(!locked)
return;
sem->off();
locked=false;
}
void auto_chdir::pushdir(const string& td,bool ap) {
/* TODO: make use of fchdir(2) instead */
char *tmp = getcwd(0,0);
assert(tmp);
saved_pwd = tmp;
free(tmp);
autopop=ap;
if(chdir(td.c_str()))
throw konforka::exception(CODEPOINT,"failed to chdir()");
}
void auto_chdir::popdir() {
autopop=false;
if(chdir(saved_pwd.c_str()))
throw konforka::exception(CODEPOINT,"failed to chdir()");
// XXX: or should it be thrown? after all we call it from destructor...
}
}
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