By libbpf_set_print(), users of libbpf are allowed to register he/she own debug, info and warning printing functions. Libbpf will use those functions to print messages. If not provided, default info and warning printing functions are fprintf(stderr, ...); defailt debug printing is NULL.
Signed-off-by: Wang Nan <wangn...@huawei.com> --- tools/lib/bpf/libbpf.c | 43 +++++++++++++++++++++++++++++++++++++++++++ tools/lib/bpf/libbpf.h | 4 ++++ 2 files changed, 47 insertions(+) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index bebe99a..d7a7869 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -8,8 +8,51 @@ */ #include <stdlib.h> +#include <stdio.h> +#include <stdarg.h> +#include <string.h> #include <unistd.h> #include <asm/unistd.h> #include <linux/bpf.h> #include "libbpf.h" + +#define __printf(a, b) __attribute__((format(printf, a, b))) + +__printf(1, 2) +static int __base_pr(const char *format, ...) +{ + va_list args; + int err; + + va_start(args, format); + err = vfprintf(stderr, format, args); + va_end(args); + return err; +} + +static __printf(1, 2) int (*__pr_warning)(const char *format, ...) = + __base_pr; +static __printf(1, 2) int (*__pr_info)(const char *format, ...) = + __base_pr; +static __printf(1, 2) int (*__pr_debug)(const char *format, ...) = + NULL; + +#define __pr(func, fmt, ...) \ +do { \ + if ((func)) \ + (func)("libbpf: " fmt, ##__VA_ARGS__); \ +} while(0) + +#define pr_warning(fmt, ...) __pr(__pr_warning, fmt, ##__VA_ARGS__) +#define pr_info(fmt, ...) __pr(__pr_info, fmt, ##__VA_ARGS__) +#define pr_debug(fmt, ...) __pr(__pr_debug, fmt, ##__VA_ARGS__) + +void libbpf_set_print(int (*warn)(const char *format, ...), + int (*info)(const char *format, ...), + int (*debug)(const char *format, ...)) +{ + __pr_warning = warn; + __pr_info = info; + __pr_debug = debug; +} diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 10845a0..eb306c0 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -9,4 +9,8 @@ #ifndef __BPF_LIBBPF_H #define __BPF_LIBBPF_H +void libbpf_set_print(int (*warn)(const char *format, ...), + int (*info)(const char *format, ...), + int (*debug)(const char *format, ...)); + #endif -- 1.8.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/