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author | Joel Sherrill <joel.sherrill@OARcorp.com> | 1999-11-02 18:00:15 +0000 |
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committer | Joel Sherrill <joel.sherrill@OARcorp.com> | 1999-11-02 18:00:15 +0000 |
commit | 799c767d319d65c94b3770e82490c8dd4dc80378 (patch) | |
tree | bf9909c7f3ae617a34e401a0f88dc314f982f772 /cpukit/posix/src/semopen.c | |
parent | Split some more stuff out of psignal.c. (diff) | |
download | rtems-799c767d319d65c94b3770e82490c8dd4dc80378.tar.bz2 |
Split the POSIX semaphore manager into multiple files.
Diffstat (limited to '')
-rw-r--r-- | cpukit/posix/src/semopen.c | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/cpukit/posix/src/semopen.c b/cpukit/posix/src/semopen.c new file mode 100644 index 0000000000..c0ac7ffe3b --- /dev/null +++ b/cpukit/posix/src/semopen.c @@ -0,0 +1,109 @@ +/* + * $Id$ + */ + +#include <stdarg.h> + +#include <errno.h> +#include <fcntl.h> +#include <pthread.h> +#include <semaphore.h> +#include <limits.h> + +#include <rtems/system.h> +#include <rtems/score/object.h> +#include <rtems/posix/semaphore.h> +#include <rtems/posix/time.h> +#include <rtems/posix/seterr.h> + +/*PAGE + * + * 11.2.3 Initialize/Open a Named Semaphore, P1003.1b-1993, p.221 + * + * NOTE: When oflag is O_CREAT, then optional third and fourth + * parameters must be present. + */ + +sem_t *sem_open( + const char *name, + int oflag, + ... + /* mode_t mode, */ + /* unsigned int value */ +) +{ + va_list arg; + mode_t mode; + unsigned int value = 0; + int status; + Objects_Id the_semaphore_id; + POSIX_Semaphore_Control *the_semaphore; + Objects_Locations location; + + + if ( oflag & O_CREAT ) { + va_start(arg, oflag); + /*mode = (mode_t) va_arg( arg, mode_t * );*/ + mode = va_arg( arg, mode_t ); + /*value = (unsigned int) va_arg( arg, unsigned int * );*/ + value = va_arg( arg, unsigned int ); + va_end(arg); + } + + status = _POSIX_Semaphore_Name_to_id( name, &the_semaphore_id ); + + /* + * If the name to id translation worked, then the semaphore exists + * and we can just return a pointer to the id. Otherwise we may + * need to check to see if this is a "semaphore does not exist" + * or some other miscellaneous error on the name. + */ + + if ( status ) { + + if ( status == EINVAL ) { /* name -> ID translation failed */ + if ( !(oflag & O_CREAT) ) { /* willing to create it? */ + set_errno_and_return_minus_one_cast( ENOENT, sem_t * ); + } + /* we are willing to create it */ + } + /* some type of error */ + /*set_errno_and_return_minus_one_cast( status, sem_t * );*/ + + } else { /* name -> ID translation succeeded */ + + if ( (oflag & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL) ) { + set_errno_and_return_minus_one_cast( EEXIST, sem_t * ); + } + + /* + * XXX In this case we need to do an ID->pointer conversion to + * check the mode. This is probably a good place for a subroutine. + */ + + the_semaphore = _POSIX_Semaphore_Get( &the_semaphore_id, &location ); + the_semaphore->open_count += 1; + + return (sem_t *)&the_semaphore->Object.id; + + } + + /* XXX verify this comment... + * + * At this point, the semaphore does not exist and everything has been + * checked. We should go ahead and create a semaphore. + */ + + status = _POSIX_Semaphore_Create_support( + name, + FALSE, /* not shared across processes */ + value, + &the_semaphore + ); + + if ( status == -1 ) + return (sem_t *) -1; + + return (sem_t *) &the_semaphore->Object.id; + +} |