projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| c9be6cfe KB |
1 | /*- |
| 2 | * Copyright (c) 1990 The Regents of the University of California. | |
| 3 | * All rights reserved. | |
| 4 | * | |
| 5 | * This code is derived from software contributed to Berkeley by | |
| 6 | * Chris Torek. | |
| 7 | * | |
| 8 | * %sccs.include.redist.c% | |
| 9 | */ | |
| 10 | ||
| 11 | #if defined(LIBC_SCCS) && !defined(lint) | |
| 12 | static char sccsid[] = "@(#)flags.c 5.1 (Berkeley) %G%"; | |
| 13 | #endif /* LIBC_SCCS and not lint */ | |
| 14 | ||
| 15 | #include <sys/types.h> | |
| 16 | #include <sys/file.h> | |
| 17 | #include <stdio.h> | |
| 18 | #include <errno.h> | |
| 19 | ||
| 20 | /* | |
| 21 | * Return the (stdio) flags for a given mode. Store the flags | |
| 22 | * to be passed to an open() syscall through *optr. | |
| 23 | * Return 0 on error. | |
| 24 | */ | |
| 25 | __sflags(mode, optr) | |
| 26 | register char *mode; | |
| 27 | int *optr; | |
| 28 | { | |
| 29 | register int ret, m, o; | |
| 30 | ||
| 31 | switch (*mode++) { | |
| 32 | ||
| 33 | case 'r': /* open for reading */ | |
| 34 | ret = __SRD; | |
| 35 | m = O_RDONLY; | |
| 36 | o = 0; | |
| 37 | break; | |
| 38 | ||
| 39 | case 'w': /* open for writing */ | |
| 40 | ret = __SWR; | |
| 41 | m = O_WRONLY; | |
| 42 | o = O_CREAT | O_TRUNC; | |
| 43 | break; | |
| 44 | ||
| 45 | case 'a': /* open for appending */ | |
| 46 | ret = __SWR; | |
| 47 | m = O_WRONLY; | |
| 48 | o = O_CREAT | O_APPEND; | |
| 49 | break; | |
| 50 | ||
| 51 | default: /* illegal mode */ | |
| 52 | errno = EINVAL; | |
| 53 | return (0); | |
| 54 | } | |
| 55 | ||
| 56 | /* [rwa]\+ or [rwa]b\+ means read and write */ | |
| 57 | if (*mode == '+' || (*mode == 'b' && mode[1] == '+')) { | |
| 58 | ret = __SRW; | |
| 59 | m = O_RDWR; | |
| 60 | } | |
| 61 | *optr = m | o; | |
| 62 | return (ret); | |
| 63 | } |