/* function: "write_png(bmp, path[, color_type, text_dict])\n
Writes the bitmap as a png at the given path.\n
Raises OSError on failure.\n
\n
Optional parameters:\n
- color_type: A constant from the png-module (e.g. png.RGB_ALPHA)\n
- text_dict: A dictionary of key-strings to value-strings\n
for png tEXt meta-data."
name: "write_png" */
static void write_png_py(const FilePath& p,
const Bitmap& bmp,
const Optional<int>& rawColorType,
const Optional<png_tEXt_map>& maybeTextChunks)
{
const auto defaultType = static_cast<int>(PngColorType::RGB_ALPHA);
const auto colorType =
to_enum<PngColorType>(rawColorType.Or(defaultType)).Visit(
[](const PngColorType t){
return t;
},
[]() -> PngColorType{
throw ValueError("color_type out of range.");
});
auto r = maybeTextChunks.Visit(
[&](const png_tEXt_map& textChunks){
return write_png(p, bmp, colorType, textChunks);
},
[&](){
return write_png(p, bmp, colorType);
});
if (!r.Successful()){
throw OSError(r.ErrorDescription());
}
}
/* function: "read_png(path)->(bmp, text_dict)\n
Reads the png-file at path, returning a Bitmap and a
dictionary of tEXt-entries.\n
Raises OSError on failure."
name: "read_png" */
static png_pair read_png_py(const FilePath& path){
return read_png_meta(path).Visit(
[](const Bitmap_and_tEXt& obj) -> png_pair{
return {obj.bmp, obj.text};
},
[](const utf8_string& error) -> png_pair{
throw OSError(error);
});
}
void write_numpy(const string& filename,int rank,const npy_intp* dimensions,int type_num,void* data) {
// Make header
const auto H = fill_numpy_header(rank,dimensions,type_num);
// Write npy file
FILE* file = fopen(filename.c_str(),"wb");
if(!file) throw OSError("Can't open "+filename+" for writing");
fwrite(H.x.data(),1,H.x.size(),file);
fwrite(data,1,H.y,file);
fclose(file);
}
void drop_privs(uid_t uid, gid_t gid) {
if (::getuid() == (uid_t)0) { // running as root
if (::setgid(gid) != 0) {
throw OSError("failed to drop group privileges");
}
// change the uid
// use panic() rather than throw ... you can't catch+ignore panic()
if (::setuid(uid) != 0) {
panic("failed to drop privileges");
}
}
}
void wait(void) {
int status;
for(;;) {
if (::waitpid(-1, &status, 0) == (pid_t)-1) {
if (errno == ECHILD) { // no more child processes
break;
}
throw OSError("failed waitpid() call, something wrong with child process");
}
}
}
void child_trampoline__(const std::function<void()>& func) {
int status;
switch(::fork()) {
case (pid_t)-1:
throw OSError("failed to fork off a child process");
break;
case (pid_t)0:
// child process; this is a forked copy
assign_tid();
func();
std::exit(0); // terminate child process
break;
default:
assign_tid();
if (::waitpid(-1, &status, WNOHANG) == (pid_t)-1 && errno != ECHILD) {
throw OSError("failed waitpid() call, something wrong with child process");
}
}
}
BoundedFile::BoundedFile( const string & path,
const int64_t end )
: m_sPath( path ),
m_iEnd( end ),
m_file( open( path.c_str(), O_RDONLY ) ),
m_pBIO( BIO_new( &boundedMethods ) )
{
if ( m_file < 0 )
throw OSError( "opening " + QS( path ) );
DEBUG( "bf: ctor: path=" << QS( path ) << ", end=" << end );
m_pBIO->ptr = this;
m_pBIO->init = 1;
}
Process::Process(const char* file, char *argv[]) {
static char none[] = "";
if(argv == 0) {
//For some unknow reason, 'argv = &none" is wrong:
//cannot convert 'char (*)[1]' to 'char**' in an assignament
char *p = none;
argv = &p;
}
Log::debug("Spawning the process %s.", file);
pid_t pid = fork();
if(pid == 0) {
// children process
execv(file, argv);
throw OSError("The process's image '%s' cannot be loaded.", file);
}else if(pid == -1) {
throw OSError("The process's children cannot be created (forked).");
}else {
// parent process
Log::debug("Spawned the process %s (PID %i).", file, pid);
this->pid = pid;
}
}
// launch function as thread
// invoked by go(func, arg1, arg2, ...)
void go_trampoline__(const std::function<void()>& func) {
std::lock_guard<std::mutex> guard(thread_mgr_lock);
std::atomic<int> start;
start = 0;
try {
// keep the thread as variable in the thread_mgr array
thread_mgr.push_back(std::thread(go_thread_main, func, &start));
} catch(std::system_error) {
throw OSError("failed to start thread");
}
// spinlock ... eek
// how to improve this, without destroying locks before the thread ever
// got to them, etc. ?
while(start == 0);
}
int
BoundedFile::read( char * buf, int bufLen )
{
const off64_t cur( lseek64( m_file, 0, SEEK_CUR ) );
if ( cur == static_cast< off64_t >( -1 ) )
throw OSError( "finding current offset in " + QS( m_sPath ) );
const size_t len(
static_cast< size_t >(
( m_iEnd < cur + bufLen ) ? m_iEnd - cur : bufLen
)
);
const int rv = static_cast< int >( ::read( m_file, buf, len ) );
DEBUG_FINE( "bf-rd: " << QS( m_sPath ) << ": "
"end=" << m_iEnd << ", cur=" << cur << ", "
"len=" << len << ", rv=" << rv );
return rv;
}
void daemonize(bool goto_background) {
if (getppid() == 1) {
// if started from init, skip the most part
goto_background = false;
// close all file descriptors
for(int fd = ::getdtablesize()-1; fd >= 0; fd--)
::close(fd);
// reopen stdin, stdout, stderr as /dev/null
int fd = ::open("/dev/null", O_RDWR);
if (fd >= 0) {
::dup(fd);
::dup(fd);
}
}
if (goto_background) {
::signal(SIGTTOU, SIG_IGN);
::signal(SIGTTIN, SIG_IGN);
::signal(SIGTSTP, SIG_IGN);
pid_t pid = ::fork();
if (pid == (pid_t)-1) {
throw OSError("failed to fork");
}
if (pid > 0) { // parent exits
std::exit(0);
}
::setsid();
// lose controlling tty
int fd = ::open("/dev/tty", O_WRONLY);
if (fd >= 0) {
::ioctl(fd, TIOCNOTTY, nullptr);
::close(fd);
}
::setpgrp();
// fork again
pid = ::fork();
if (pid == (pid_t)-1) {
throw OSError("failed to fork");
}
if (pid > 0) { // parent exits
std::exit(0);
}
// close all file descriptors
for(int fd = ::getdtablesize()-1; fd >= 0; fd--) {
::close(fd);
}
// reopen stdin, stdout, stderr as /dev/null
if ((fd = ::open("/dev/null", O_RDWR)) >= 0) {
::dup(fd);
::dup(fd);
}
}
::chdir("/");
::umask(022);
}
void Process::send_signal(int signal, bool expect_alive) {
if(kill(pid, signal) == -1) {
if(errno == ESRCH and not expect_alive) return
throw OSError("Error when sending a signal -%i to the process children with PID %i", signal, pid);
}
}
int Process::wait() {
int status = -1;
if(waitpid(pid, &status, 0) == -1)
throw OSError("Error when waiting for the process children with PID %i finish", pid);
return status;
}