Subject: [PATCH AUTOSEL 4.20 180/304] tools: bpftool: fix -Wmissing declaration warnings

From: Sasha Levin <[email-masked]>
Date: Mon, 28 Jan 2019 10:41:37 -0500

From: Quentin Monnet <[email-masked]>

[ Upstream commit c101189bc9680675a2686bafe908015a07a0da51 ]

Help compiler check arguments for several utility functions used to
print items to the console by adding the "printf" attribute when
declaring those functions.

Also, declare as "static" two functions that are only used in prog.c.

All of them discovered by compiling bpftool with
-Wmissing-format-attribute -Wmissing-declarations.

Signed-off-by: Quentin Monnet <[email-masked]>
Reviewed-by: Jakub Kicinski <[email-masked]>
Signed-off-by: Daniel Borkmann <[email-masked]>
Signed-off-by: Sasha Levin <[email-masked]>
---
 tools/bpf/bpftool/common.c        | 4 ++--
 tools/bpf/bpftool/json_writer.c   | 6 ++++--
 tools/bpf/bpftool/prog.c          | 4 ++--
 tools/bpf/bpftool/xlated_dumper.c | 7 ++++---
 4 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c
index 70fd48d79f61..05d715e6b128 100644
--- a/tools/bpf/bpftool/common.c
+++ b/tools/bpf/bpftool/common.c
@@ -58,7 +58,7 @@
 #define BPF_FS_MAGIC		0xcafe4a11
 #endif
 
-void p_err(const char *fmt, ...)
+void __printf(1, 2) p_err(const char *fmt, ...)
 {
 	va_list ap;
 
@@ -76,7 +76,7 @@ void p_err(const char *fmt, ...)
 	va_end(ap);
 }
 
-void p_info(const char *fmt, ...)
+void __printf(1, 2) p_info(const char *fmt, ...)
 {
 	va_list ap;
 
diff --git a/tools/bpf/bpftool/json_writer.c b/tools/bpf/bpftool/json_writer.c
index c6eef76322ae..4e4149421d07 100644
--- a/tools/bpf/bpftool/json_writer.c
+++ b/tools/bpf/bpftool/json_writer.c
@@ -19,6 +19,7 @@
 #include <malloc.h>
 #include <inttypes.h>
 #include <stdint.h>
+#include <linux/compiler.h>
 
 #include "json_writer.h"
 
@@ -156,7 +157,8 @@ void jsonw_name(json_writer_t *self, const char *name)
 		putc(' ', self->out);
 }
 
-void jsonw_vprintf_enquote(json_writer_t *self, const char *fmt, va_list ap)
+void __printf(2, 0)
+jsonw_vprintf_enquote(json_writer_t *self, const char *fmt, va_list ap)
 {
 	jsonw_eor(self);
 	putc('"', self->out);
@@ -164,7 +166,7 @@ void jsonw_vprintf_enquote(json_writer_t *self, const char *fmt, va_list ap)
 	putc('"', self->out);
 }
 
-void jsonw_printf(json_writer_t *self, const char *fmt, ...)
+void __printf(2, 3) jsonw_printf(json_writer_t *self, const char *fmt, ...)
 {
 	va_list ap;
 
diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index ccee180dfb76..69b01a6158bd 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -84,7 +84,7 @@ static const char * const attach_type_strings[] = {
 	[__MAX_BPF_ATTACH_TYPE] = NULL,
 };
 
-enum bpf_attach_type parse_attach_type(const char *str)
+static enum bpf_attach_type parse_attach_type(const char *str)
 {
 	enum bpf_attach_type type;
 
@@ -713,7 +713,7 @@ struct map_replace {
 	char *name;
 };
 
-int map_replace_compar(const void *p1, const void *p2)
+static int map_replace_compar(const void *p1, const void *p2)
 {
 	const struct map_replace *a = p1, *b = p2;
 
diff --git a/tools/bpf/bpftool/xlated_dumper.c b/tools/bpf/bpftool/xlated_dumper.c
index 3284759df98a..98083e4dc0f9 100644
--- a/tools/bpf/bpftool/xlated_dumper.c
+++ b/tools/bpf/bpftool/xlated_dumper.c
@@ -114,7 +114,7 @@ struct kernel_sym *kernel_syms_search(struct dump_data *dd,
 		       sizeof(*dd->sym_mapping), kernel_syms_cmp) : NULL;
 }
 
-static void print_insn(void *private_data, const char *fmt, ...)
+static void __printf(2, 3) print_insn(void *private_data, const char *fmt, ...)
 {
 	va_list args;
 
@@ -123,7 +123,7 @@ static void print_insn(void *private_data, const char *fmt, ...)
 	va_end(args);
 }
 
-static void
+static void __printf(2, 3)
 print_insn_for_graph(void *private_data, const char *fmt, ...)
 {
 	char buf[64], *p;
@@ -154,7 +154,8 @@ print_insn_for_graph(void *private_data, const char *fmt, ...)
 	printf("%s", buf);
 }
 
-static void print_insn_json(void *private_data, const char *fmt, ...)
+static void __printf(2, 3)
+print_insn_json(void *private_data, const char *fmt, ...)
 {
 	unsigned int l = strlen(fmt);
 	char chomped_fmt[l];
-- 
2.19.1