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#define _GNU_SOURCE /* for Linux O_DIRECT */
#include <u.h>
#define NOPLAN9DEFINES
#include <sys/file.h>
#include <libc.h>
#ifndef O_DIRECT
#define O_DIRECT 0
#endif
int
p9open(char *name, int mode)
{
int cexec, rclose;
int fd, umode, lock, rdwr;
struct flock fl;
rdwr = mode&3;
umode = rdwr;
cexec = mode&OCEXEC;
rclose = mode&ORCLOSE;
lock = mode&OLOCK;
mode &= ~(3|OCEXEC|ORCLOSE|OLOCK);
if(mode&OTRUNC){
umode |= O_TRUNC;
mode ^= OTRUNC;
}
if(mode&ODIRECT){
umode |= O_DIRECT;
mode ^= ODIRECT;
}
if(mode&ONONBLOCK){
umode |= O_NONBLOCK;
mode ^= ONONBLOCK;
}
if(mode&OAPPEND){
umode |= O_APPEND;
mode ^= OAPPEND;
}
if(mode){
werrstr("mode 0x%x not supported", mode);
return -1;
}
fd = open(name, umode);
if(fd >= 0){
if(lock){
fl.l_type = (rdwr==OREAD) ? F_RDLCK : F_WRLCK;
fl.l_whence = SEEK_SET;
fl.l_start = 0;
fl.l_len = 0;
if(fcntl(fd, F_SETLK, &fl) < 0){
close(fd);
werrstr("lock: %r");
return -1;
}
}
if(cexec)
fcntl(fd, F_SETFD, FD_CLOEXEC);
if(rclose)
remove(name);
}
return fd;
}
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