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49 lines
1019 B
C
49 lines
1019 B
C
/*
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* l4/posix glue for lseek()
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*
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* Copyright (C) 2007 Bahadir Balban
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*/
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#include <errno.h>
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#include <stdio.h>
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#include <sys/types.h>
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#include <unistd.h>
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#include <l4lib/ipcdefs.h>
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#include <libposix.h>
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static inline off_t l4_lseek(int fildes, off_t offset, int whence)
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{
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off_t offres;
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write_mr(L4SYS_ARG0, fildes);
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write_mr(L4SYS_ARG1, offset);
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write_mr(L4SYS_ARG2, whence);
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/* Call pager with shmget() request. Check ipc error. */
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if ((offres = l4_sendrecv(pagerid, pagerid, L4_IPC_TAG_LSEEK)) < 0) {
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print_err("%s: L4 IPC Error: %d.\n", __FUNCTION__, offres);
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return offres;
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}
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/* Check if syscall itself was successful */
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if ((offres = l4_get_retval()) < 0) {
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print_err("%s: OPEN Error: %d.\n", __FUNCTION__, (int)offres);
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return offres;
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}
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return offres;
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}
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off_t lseek(int fildes, off_t offset, int whence)
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{
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int ret = l4_lseek(fildes, offset, whence);
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/* If error, return positive error code */
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if (ret < 0) {
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errno = -ret;
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return -1;
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}
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/* else return value */
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return ret;
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}
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