diff options
Diffstat (limited to 'cpukit/libcsupport/src/libio.c')
| -rw-r--r-- | cpukit/libcsupport/src/libio.c | 433 |
1 files changed, 433 insertions, 0 deletions
diff --git a/cpukit/libcsupport/src/libio.c b/cpukit/libcsupport/src/libio.c new file mode 100644 index 0000000000..ce41643a09 --- /dev/null +++ b/cpukit/libcsupport/src/libio.c @@ -0,0 +1,433 @@ +/* + * @(#)libio.c 1.1 - 95/06/02 + * + * + * Provide UNIX/POSIX-like io system calls for RTEMS using the + * RTEMS IO manager + * + * TODO + * + * $Id$ + */ + +#include <rtems.h> +#include <rtems/assoc.h> /* assoc.h not included by rtems.h */ + +#include <fcntl.h> /* O_RDONLY, et.al. */ +#if defined(solaris2) +#define O_NDELAY O_NONBLOCK +#endif +#include <errno.h> +#include <string.h> /* strcmp */ +#include <unistd.h> +#include <stdlib.h> /* calloc() */ + +#include "libio.h" /* libio.h not pulled in by rtems */ + +/* + * Semaphore to protect the io table + */ + +Objects_Id rtems_libio_semaphore; + +#define RTEMS_LIBIO_SEM rtems_build_name('L', 'B', 'I', 'O') +#define RTEMS_LIBIO_IOP_SEM(n) rtems_build_name('L', 'B', 'I', n) + +unsigned32 rtems_libio_number_iops; +rtems_libio_t *rtems_libio_iops; +rtems_libio_t *rtems_libio_last_iop; + +#define rtems_libio_iop(fd) ((((unsigned32)(fd)) < rtems_libio_number_iops) ? \ + &rtems_libio_iops[fd] : 0) + +#define rtems_libio_check_fd(fd) \ + do { \ + if ((fd) >= rtems_libio_number_iops) \ + { \ + errno = EBADF; \ + return -1; \ + } \ + } while (0) + +#define rtems_libio_check_buffer(buffer) \ + do { \ + if ((buffer) == 0) \ + { \ + errno = EINVAL; \ + return -1; \ + } \ + } while (0) + +#define rtems_libio_check_count(count) \ + do { \ + if ((count) == 0) \ + { \ + return 0; \ + } \ + } while (0) + +#define rtems_libio_check_permissions(iop, flag) \ + do { \ + if (((iop)->flags & (flag)) == 0) \ + { \ + errno = EINVAL; \ + return -1; \ + } \ + } while (0) + + +void +rtems_libio_config( + rtems_configuration_table *config, + unsigned32 max_fds + ) +{ + rtems_libio_number_iops = max_fds; + + /* + * tweak config to reflect # of semaphores we will need + */ + + config->maximum_semaphores += 1; /* one for iop table */ + config->maximum_semaphores += max_fds; +} + +/* + * Called by bsp startup code to init the libio area. + */ + +void +rtems_libio_init(void) +{ + rtems_status_code rc; + + if (rtems_libio_number_iops > 0) + { + rtems_libio_iops = (rtems_libio_t *) calloc(rtems_libio_number_iops, + sizeof(rtems_libio_t)); + if (rtems_libio_iops == NULL) + rtems_fatal_error_occurred(RTEMS_NO_MEMORY); + + rtems_libio_last_iop = rtems_libio_iops + (rtems_libio_number_iops - 1); + } + + rc = rtems_semaphore_create(RTEMS_LIBIO_SEM, + 1, + RTEMS_BINARY_SEMAPHORE | RTEMS_INHERIT_PRIORITY | RTEMS_PRIORITY, + &rtems_libio_semaphore); + if (rc != RTEMS_SUCCESSFUL) + rtems_fatal_error_occurred(rc); +} + +/* + * Convert RTEMS status to a UNIX errno + */ + +rtems_assoc_t errno_assoc[] = { + { "OK", RTEMS_SUCCESSFUL, 0 }, + { "TIMEOUT", RTEMS_TIMEOUT, ETIME }, + { "NO MEMORY", RTEMS_NO_MEMORY, ENOMEM }, + { 0, 0, 0 }, +}; + +static unsigned32 +rtems_libio_errno(rtems_status_code code) +{ + int rc; + + if ((rc = rtems_assoc_remote_by_local(errno_assoc, (unsigned32) code))) + { + errno = rc; + return -1; + } + return 0; +} + +/* + * Convert UNIX fnctl(2) flags to ones that RTEMS drivers understand + */ + +rtems_assoc_t access_modes_assoc[] = { + { "READ", LIBIO_FLAGS_READ, O_RDONLY }, + { "WRITE", LIBIO_FLAGS_WRITE, O_WRONLY }, + { "READ/WRITE", LIBIO_FLAGS_READ_WRITE, O_RDWR }, + { 0, 0, 0 }, +}; + +rtems_assoc_t status_flags_assoc[] = { + { "NO DELAY", LIBIO_FLAGS_NO_DELAY, O_NDELAY }, + { "APPEND", LIBIO_FLAGS_APPEND, O_APPEND }, + { "CREATE", LIBIO_FLAGS_CREATE, O_CREAT }, + { 0, 0, 0 }, +}; + +static unsigned32 +rtems_libio_fcntl_flags(unsigned32 fcntl_flags) +{ + unsigned32 flags = 0; + unsigned32 access_modes; + + /* + * Access mode is a small integer + */ + + access_modes = fcntl_flags & O_ACCMODE; + fcntl_flags &= ~O_ACCMODE; + flags = rtems_assoc_local_by_remote(access_modes_assoc, access_modes); + + /* + * Everything else is single bits + */ + + flags |= rtems_assoc_local_by_remote_bitfield(status_flags_assoc, fcntl_flags); + return flags; +} + + +static rtems_libio_t * +rtems_libio_allocate(void) +{ + rtems_libio_t *iop; + rtems_status_code rc; + + rtems_semaphore_obtain(rtems_libio_semaphore, RTEMS_WAIT, RTEMS_NO_TIMEOUT); + + for (iop = rtems_libio_iops; iop <= rtems_libio_last_iop; iop++) + if ((iop->flags & LIBIO_FLAGS_OPEN) == 0) + { + /* + * Got one; create a semaphore for it + */ + + rc = rtems_semaphore_create(RTEMS_LIBIO_IOP_SEM(iop - rtems_libio_iops), + 1, RTEMS_BINARY_SEMAPHORE | RTEMS_INHERIT_PRIORITY | RTEMS_PRIORITY, + &iop->sem); + if (rc != RTEMS_SUCCESSFUL) + goto failed; + + iop->flags = LIBIO_FLAGS_OPEN; + goto done; + } + +failed: + iop = 0; + +done: + rtems_semaphore_release(rtems_libio_semaphore); + return iop; +} + +static void +rtems_libio_free(rtems_libio_t *iop) +{ + rtems_semaphore_obtain(rtems_libio_semaphore, RTEMS_WAIT, RTEMS_NO_TIMEOUT); + + if (iop->sem) + rtems_semaphore_delete(iop->sem); + (void) memset(iop, 0, sizeof(*iop)); + + rtems_semaphore_release(rtems_libio_semaphore); +} + +int +__open( + const char *pathname, + unsigned32 flag, + unsigned32 mode) +{ + rtems_status_code rc; + rtems_libio_t *iop = 0; + rtems_driver_name_t *np; + rtems_libio_open_close_args_t args; + + if ((rc = rtems_io_lookup_name(pathname, &np)) != RTEMS_SUCCESSFUL) + goto done; + + iop = rtems_libio_allocate(); + if (iop == 0) + { + rc = RTEMS_TOO_MANY; + goto done; + } + + iop->driver = np; + iop->pathname = (char *) pathname; + iop->flags |= rtems_libio_fcntl_flags(flag); + + args.iop = iop; + args.flags = iop->flags; + args.mode = mode; + + rc = rtems_io_open(np->major, np->minor, (void *) &args); + +done: + if (rc != RTEMS_SUCCESSFUL) + { + if (iop) + rtems_libio_free(iop); + return rtems_libio_errno(rc); + } + + return iop - rtems_libio_iops; +} + +int +__close( + int fd + ) +{ + rtems_status_code rc; + rtems_driver_name_t *np; + rtems_libio_t *iop = rtems_libio_iop(fd); + rtems_libio_open_close_args_t args; + + rtems_libio_check_fd(fd); + + np = iop->driver; + + args.iop = iop; + args.flags = 0; + args.mode = 0; + + rc = rtems_io_close(np->major, np->minor, (void *) &args); + + if (rc != RTEMS_SUCCESSFUL) + return rtems_libio_errno(rc); + return 0; +} + +int +__read( + int fd, + void * buffer, + unsigned32 count + ) +{ + rtems_status_code rc; + rtems_driver_name_t *np; + rtems_libio_t *iop = rtems_libio_iop(fd); + rtems_libio_rw_args_t args; + + rtems_libio_check_fd(fd); + rtems_libio_check_buffer(buffer); + rtems_libio_check_count(count); + rtems_libio_check_permissions(iop, LIBIO_FLAGS_READ); + + np = iop->driver; + + args.iop = iop; + args.offset = iop->offset; + args.buffer = buffer; + args.count = count; + args.flags = iop->flags; + args.bytes_moved = 0; + + rc = rtems_io_read(np->major, np->minor, (void *) &args); + + iop->offset += args.bytes_moved; + + if (rc != RTEMS_SUCCESSFUL) + return rtems_libio_errno(rc); + + return args.bytes_moved; +} + +int +__write( + int fd, + const void *buffer, + unsigned32 count + ) +{ + rtems_status_code rc; + rtems_driver_name_t *np; + rtems_libio_t *iop = rtems_libio_iop(fd); + rtems_libio_rw_args_t args; + + rtems_libio_check_fd(fd); + rtems_libio_check_buffer(buffer); + rtems_libio_check_count(count); + rtems_libio_check_permissions(iop, LIBIO_FLAGS_WRITE); + + np = iop->driver; + + args.iop = iop; + args.offset = iop->offset; + args.buffer = (void *) buffer; + args.count = count; + args.flags = iop->flags; + args.bytes_moved = 0; + + rc = rtems_io_write(np->major, np->minor, (void *) &args); + + iop->offset += args.bytes_moved; + + if (rc != RTEMS_SUCCESSFUL) + return rtems_libio_errno(rc); + + return args.bytes_moved; +} + +int +__ioctl( + int fd, + unsigned32 command, + void * buffer) +{ + rtems_status_code rc; + rtems_driver_name_t *np; + rtems_libio_t *iop = rtems_libio_iop(fd); + rtems_libio_ioctl_args_t args; + + rtems_libio_check_fd(fd); + + np = iop->driver; + + args.iop = iop; + args.command = command; + args.buffer = buffer; + + rc = rtems_io_control(np->major, np->minor, (void *) &args); + + if (rc != RTEMS_SUCCESSFUL) + return rtems_libio_errno(rc); + + return args.ioctl_return; +} + +/* + * internal only?? + */ + + +int +__lseek( + int fd, + rtems_libio_offset_t offset, + int whence + ) +{ + rtems_libio_t *iop = rtems_libio_iop(fd); + + rtems_libio_check_fd(fd); + + switch (whence) + { + case SEEK_SET: + iop->offset = offset; + break; + + case SEEK_CUR: + iop->offset += offset; + break; + + case SEEK_END: + iop->offset = iop->size - offset; + break; + + default: + errno = EINVAL; + return -1; + } + return 0; +} |