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[PATCH] tools-perf: Change -1 by false

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Returning a negative value for a boolean function seem to have the
undesired effect of returning true. Replace -1 by false in a
bool-returning function.

The diff of the .s file before and after the change (for x86_64):
3907c3907
< 	movl	$1, %ebx
---
> 	xorl	%ebx, %ebx

while if -1 is replaced by true, the diff is empty.

This issue was found by the following Coccinelle semantic patch:
<smpl>
@@
identifier f;
constant C;
typedef bool;
@@
bool f (...){
<+...
* return -C;
...+>
}
</smpl>

Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
---
 tools/perf/util/util.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
index 49a5c6a..ce465b2 100644
--- a/tools/perf/util/util.c
+++ b/tools/perf/util/util.c
@@ -639,7 +639,7 @@ bool find_process(const char *name)
 
 	dir = opendir(procfs__mountpoint());
 	if (!dir)
-		return -1;
+		return false;
 
 	/* Walk through the directory. */
 	while (ret && (d = readdir(dir)) != NULL) {
-- 
2.1.0

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[PATCH] tools-perf: Change -1 by false Peter Senna Tschudin <peter.senna@gmail.com> - 2015-09-17 12:10 +0200
  Re: [PATCH] tools-perf: Change -1 by false Arnaldo Carvalho de Melo <acme@kernel.org> - 2015-09-17 20:40 +0200
  [tip:perf/urgent] perf tools: Bool functions shouldn't return -1 tip-bot for Peter Senna Tschudin <tipbot@zytor.com> - 2015-09-18 08:00 +0200

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