summaryrefslogtreecommitdiff
path: root/tools/lib
diff options
context:
space:
mode:
authorArnaldo Carvalho de Melo <acme@redhat.com>2016-07-06 11:56:20 -0300
committerArnaldo Carvalho de Melo <acme@redhat.com>2016-07-12 15:19:47 -0300
commitc8b5f2c96d1bf6cefcbe12f67dce0b892fe20512 (patch)
treee6f40aa67f1a3ea28c53bf74fc1d51c9c3ec74c2 /tools/lib
parentffe3a28a8b90879c21acf7a1a8f5277785b05ff6 (diff)
tools: Introduce str_error_r()
The tools so far have been using the strerror_r() GNU variant, that returns a string, be it the buffer passed or something else. But that, besides being tricky in cases where we expect that the function using strerror_r() returns the error formatted in a provided buffer (we have to check if it returned something else and copy that instead), breaks the build on systems not using glibc, like Alpine Linux, where musl libc is used. So, introduce yet another wrapper, str_error_r(), that has the GNU interface, but uses the portable XSI variant of strerror_r(), so that users rest asured that the provided buffer is used and it is what is returned. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-d4t42fnf48ytlk8rjxs822tf@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/lib')
-rw-r--r--tools/lib/str_error_r.c26
1 files changed, 26 insertions, 0 deletions
diff --git a/tools/lib/str_error_r.c b/tools/lib/str_error_r.c
new file mode 100644
index 000000000000..503ae072244c
--- /dev/null
+++ b/tools/lib/str_error_r.c
@@ -0,0 +1,26 @@
+#undef _GNU_SOURCE
+#include <string.h>
+#include <stdio.h>
+#include <linux/string.h>
+
+/*
+ * The tools so far have been using the strerror_r() GNU variant, that returns
+ * a string, be it the buffer passed or something else.
+ *
+ * But that, besides being tricky in cases where we expect that the function
+ * using strerror_r() returns the error formatted in a provided buffer (we have
+ * to check if it returned something else and copy that instead), breaks the
+ * build on systems not using glibc, like Alpine Linux, where musl libc is
+ * used.
+ *
+ * So, introduce yet another wrapper, str_error_r(), that has the GNU
+ * interface, but uses the portable XSI variant of strerror_r(), so that users
+ * rest asured that the provided buffer is used and it is what is returned.
+ */
+char *str_error_r(int errnum, char *buf, size_t buflen)
+{
+ int err = strerror_r(errnum, buf, buflen);
+ if (err)
+ snprintf(buf, buflen, "INTERNAL ERROR: strerror_r(%d, %p, %zd)=%d", errnum, buf, buflen, err);
+ return buf;
+}