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| author | The Android Open Source Project <initial-contribution@android.com> | 2008-10-21 07:00:00 -0700 |
|---|---|---|
| committer | The Android Open Source Project <initial-contribution@android.com> | 2008-10-21 07:00:00 -0700 |
| commit | a27d2baa0c1a2ec70f47ea9199b1dd6762c8a349 (patch) | |
| tree | defd1cc07d16ad2f3b21154114e092d11c94c5bb /libc/kernel/common/linux/circ_buf.h | |
| download | bionic-a27d2baa0c1a2ec70f47ea9199b1dd6762c8a349.zip bionic-a27d2baa0c1a2ec70f47ea9199b1dd6762c8a349.tar.gz bionic-a27d2baa0c1a2ec70f47ea9199b1dd6762c8a349.tar.bz2 | |
Initial Contributionandroid-1.0
Diffstat (limited to 'libc/kernel/common/linux/circ_buf.h')
| -rw-r--r-- | libc/kernel/common/linux/circ_buf.h | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/libc/kernel/common/linux/circ_buf.h b/libc/kernel/common/linux/circ_buf.h new file mode 100644 index 0000000..438250c --- /dev/null +++ b/libc/kernel/common/linux/circ_buf.h @@ -0,0 +1,29 @@ +/**************************************************************************** + **************************************************************************** + *** + *** This header was automatically generated from a Linux kernel header + *** of the same name, to make information necessary for userspace to + *** call into the kernel available to libc. It contains only constants, + *** structures, and macros generated from the original header, and thus, + *** contains no copyrightable information. + *** + **************************************************************************** + ****************************************************************************/ +#ifndef _LINUX_CIRC_BUF_H +#define _LINUX_CIRC_BUF_H 1 + +struct circ_buf { + char *buf; + int head; + int tail; +}; + +#define CIRC_CNT(head,tail,size) (((head) - (tail)) & ((size)-1)) + +#define CIRC_SPACE(head,tail,size) CIRC_CNT((tail),((head)+1),(size)) + +#define CIRC_CNT_TO_END(head,tail,size) ({int end = (size) - (tail); int n = ((head) + end) & ((size)-1); n < end ? n : end;}) + +#define CIRC_SPACE_TO_END(head,tail,size) ({int end = (size) - 1 - (head); int n = (end + (tail)) & ((size)-1); n <= end ? n : end+1;}) + +#endif |
