[PATCH] perf jvmti: Properly handle return value checks in jvmti_write_code

[Luo Yifan]

Following the approach in the jvmti_write_debug_info function, add
some return value checks in jvmti_write_code.

Signed-off-by: Luo Yifan <luoyifan@xxxxxxxxxxxxxxxxxxxx>
---
 tools/perf/jvmti/jvmti_agent.c | 27 +++++++++++++++++----------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/tools/perf/jvmti/jvmti_agent.c b/tools/perf/jvmti/jvmti_agent.c
index 526dcaf9f..b52466a0c 100644
--- a/tools/perf/jvmti/jvmti_agent.c
+++ b/tools/perf/jvmti/jvmti_agent.c
@@ -361,9 +361,8 @@ jvmti_write_code(void *agent, char const *sym,
 {
 	static int code_generation = 1;
 	struct jr_code_load rec;
-	size_t sym_len;
+	size_t sret, sym_len;
 	FILE *fp = agent;
-	int ret = -1;
 
 	/* don't care about 0 length function, no samples */
 	if (size == 0)
@@ -400,17 +399,25 @@ jvmti_write_code(void *agent, char const *sym,
 	 */
 	rec.code_index = code_generation++;
 
-	ret = fwrite_unlocked(&rec, sizeof(rec), 1, fp);
-	fwrite_unlocked(sym, sym_len, 1, fp);
-
-	if (code)
-		fwrite_unlocked(code, size, 1, fp);
+	sret = fwrite_unlocked(&rec, sizeof(rec), 1, fp);
+	if (sret != 1)
+		goto error;
 
-	funlockfile(fp);
+	sret = fwrite_unlocked(sym, sym_len, 1, fp);
+	if (sret != 1)
+		goto error;
 
-	ret = 0;
+	if (code) {
+		sret = fwrite_unlocked(code, size, 1, fp);
+		if (sret != 1)
+			goto error;
+	}
 
-	return ret;
+	funlockfile(fp);
+	return 0;
+error:
+	funlockfile(fp);
+	return -1;
 }
 
 int
-- 
2.33.0