File: open.c

package info (click to toggle)
9base 1%3A6-7
  • links: PTS, VCS
  • area: main
  • in suites: buster, stretch
  • size: 5,376 kB
  • sloc: ansic: 61,051; yacc: 1,991; asm: 1,621; cs: 1,150; perl: 965; makefile: 613; sh: 12; sed: 4
file content (62 lines) | stat: -rw-r--r-- 1,082 bytes parent folder | download | duplicates (3)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
#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;
}