[PATCH 04/17] tools lib api fs: Add filename__read_xll function

Jiri Olsa
2018-02-06T18:28:16Z

Adding filename__read_xll function to be able to read files
with hex numbers in, which do not have 0x prefix.

Link: http://lkml.kernel.org/n/tip-d9qv8n8xlmkywsb9vdrcj796@git.kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/lib/api/fs/fs.c | 29 ++++++++++++++++++++++-------
tools/lib/api/fs/fs.h | 1 +
2 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/tools/lib/api/fs/fs.c b/tools/lib/api/fs/fs.c
index b24afc0e6e81..8b0e4a4315bd 100644
--- a/tools/lib/api/fs/fs.c
+++ b/tools/lib/api/fs/fs.c
@@ -315,12 +315,8 @@ int filename__read_int(const char *filename, int *value)
return err;
}

-/*
- * Parses @value out of @filename with strtoull.
- * By using 0 for base, the strtoull detects the
- * base automatically (see man strtoull).
- */
-int filename__read_ull(const char *filename, unsigned long long *value)
+static int filename__read_ull_base(const char *filename,
+ unsigned long long *value, int base)
{
char line[64];
int fd = open(filename, O_RDONLY), err = -1;
@@ -329,7 +325,7 @@ int filename__read_ull(const char *filename, unsigned long long *value)
return -1;

if (read(fd, line, sizeof(line)) > 0) {
- *value = strtoull(line, NULL, 0);
+ *value = strtoull(line, NULL, base);
if (*value != ULLONG_MAX)
err = 0;
}
@@ -338,6 +334,25 @@ int filename__read_ull(const char *filename, unsigned long long *value)
return err;
}

+/*
+ * Parses @value out of @filename with strtoull.
+ * By using 16 for base to treat the number as hex.
+ */
+int filename__read_xll(const char *filename, unsigned long long *value)
+{
+ return filename__read_ull_base(filename, value, 16);
+}
+
+/*
+ * Parses @value out of @filename with strtoull.
+ * By using 0 for base, the strtoull detects the
+ * base automatically (see man strtoull).
+ */
+int filename__read_ull(const char *filename, unsigned long long *value)
+{
+ return filename__read_ull_base(filename, value, 0);
+}
+
#define STRERR_BUFSIZE 128 /* For the buffer size of strerror_r */

int filename__read_str(const char *filename, char **buf, size_t *sizep)
diff --git a/tools/lib/api/fs/fs.h b/tools/lib/api/fs/fs.h
index dda49deefb52..8ebee35a6395 100644
--- a/tools/lib/api/fs/fs.h
+++ b/tools/lib/api/fs/fs.h
@@ -30,6 +30,7 @@ FS(bpf_fs)

int filename__read_int(const char *filename, int *value);
int filename__read_ull(const char *filename, unsigned long long *value);
+int filename__read_xll(const char *filename, unsigned long long *value);
int filename__read_str(const char *filename, char **buf, size_t *sizep);

int filename__write_int(const char *filename, int value);
--
2.13.6