730760e90a
Some locking documentation and a cleanup. uml_exitcode is copied into a local before sprintf sees it, in case sprintf does anything non-atomic with it. The rest are comments about why certain globals don't need any kind of locking. Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
58 lines
1.3 KiB
C
58 lines
1.3 KiB
C
/*
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* Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
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* Licensed under the GPL
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*/
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#include <stdlib.h>
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#include <errno.h>
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#include "chan_user.h"
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#include "os.h"
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/* This address is used only as a unique identifer */
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static int null_chan;
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static void *null_init(char *str, int device, const struct chan_opts *opts)
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{
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return(&null_chan);
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}
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static int null_open(int input, int output, int primary, void *d,
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char **dev_out)
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{
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*dev_out = NULL;
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return(os_open_file(DEV_NULL, of_rdwr(OPENFLAGS()), 0));
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}
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static int null_read(int fd, char *c_out, void *unused)
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{
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return(-ENODEV);
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}
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static void null_free(void *data)
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{
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}
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const struct chan_ops null_ops = {
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.type = "null",
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.init = null_init,
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.open = null_open,
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.close = generic_close,
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.read = null_read,
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.write = generic_write,
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.console_write = generic_console_write,
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.window_size = generic_window_size,
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.free = null_free,
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.winch = 0,
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};
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/*
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* Overrides for Emacs so that we follow Linus's tabbing style.
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* Emacs will notice this stuff at the end of the file and automatically
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* adjust the settings for this buffer only. This must remain at the end
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* of the file.
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* ---------------------------------------------------------------------------
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* Local variables:
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* c-file-style: "linux"
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* End:
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*/
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