tools lib api fs: Add sysfs__write_int function

Add sysfs__write_int() to ease up writing int to sysfs.  New interface
is:

  int sysfs__write_int(const char *entry, int value);

Also, introducing filename__write_int() which is useful for new helpers
to write sysctl values.

Signed-off-by: Kan Liang <Kan.liang@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Elliott <elliott@hpe.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1495825538-5230-2-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Kan Liang 2017-05-26 12:05:37 -07:00 committed by Arnaldo Carvalho de Melo
parent fd25bf8b8c
commit 3b00ea9386
2 changed files with 34 additions and 0 deletions

View File

@ -387,6 +387,22 @@ int filename__read_str(const char *filename, char **buf, size_t *sizep)
return err; return err;
} }
int filename__write_int(const char *filename, int value)
{
int fd = open(filename, O_WRONLY), err = -1;
char buf[64];
if (fd < 0)
return err;
sprintf(buf, "%d", value);
if (write(fd, buf, sizeof(buf)) == sizeof(buf))
err = 0;
close(fd);
return err;
}
int procfs__read_str(const char *entry, char **buf, size_t *sizep) int procfs__read_str(const char *entry, char **buf, size_t *sizep)
{ {
char path[PATH_MAX]; char path[PATH_MAX];
@ -480,3 +496,17 @@ int sysctl__read_int(const char *sysctl, int *value)
return filename__read_int(path, value); return filename__read_int(path, value);
} }
int sysfs__write_int(const char *entry, int value)
{
char path[PATH_MAX];
const char *sysfs = sysfs__mountpoint();
if (!sysfs)
return -1;
if (snprintf(path, sizeof(path), "%s/%s", sysfs, entry) >= PATH_MAX)
return -1;
return filename__write_int(path, value);
}

View File

@ -31,6 +31,8 @@ int filename__read_int(const char *filename, int *value);
int filename__read_ull(const char *filename, unsigned long long *value); int filename__read_ull(const char *filename, unsigned long long *value);
int filename__read_str(const char *filename, char **buf, size_t *sizep); int filename__read_str(const char *filename, char **buf, size_t *sizep);
int filename__write_int(const char *filename, int value);
int procfs__read_str(const char *entry, char **buf, size_t *sizep); int procfs__read_str(const char *entry, char **buf, size_t *sizep);
int sysctl__read_int(const char *sysctl, int *value); int sysctl__read_int(const char *sysctl, int *value);
@ -38,4 +40,6 @@ int sysfs__read_int(const char *entry, int *value);
int sysfs__read_ull(const char *entry, unsigned long long *value); int sysfs__read_ull(const char *entry, unsigned long long *value);
int sysfs__read_str(const char *entry, char **buf, size_t *sizep); int sysfs__read_str(const char *entry, char **buf, size_t *sizep);
int sysfs__read_bool(const char *entry, bool *value); int sysfs__read_bool(const char *entry, bool *value);
int sysfs__write_int(const char *entry, int value);
#endif /* __API_FS__ */ #endif /* __API_FS__ */