From: Michael Jeanson <mjeanson@efficios.com>
Date: Thu, 25 Mar 2021 17:19:34 +0000 (-0400)
Subject: Re-implement lttng_ust_strerr
X-Git-Tag: v2.13.0-rc1~189
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=d6d2eb792414485fa36c6c473f74235840c678d7;p=lttng-ust.git

Re-implement lttng_ust_strerr

Re-implement lttng_ust_strerr based on the tools internal
implementation.

 * Require a negative error code from enum lttng_ust_error_code or zero
 * Don't handle negative error codes as system errors anymore

Change-Id: I89a95f4f6b0c392c8fa7bdb3ad40a8d6ea918acf
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/include/lttng/ust-error.h b/include/lttng/ust-error.h
index de7e665f..543c894a 100644
--- a/include/lttng/ust-error.h
+++ b/include/lttng/ust-error.h
@@ -41,8 +41,11 @@ enum lttng_ust_error_code {
 };
 
 /*
- * Return a human-readable error message for an lttng-ust error code.
- * code must be a positive value (or 0).
+ * lttng_ust_strerror
+ * @code: must be a negative value of enum lttng_ust_error_code (or 0).
+ *
+ * Returns a ptr to a string representing a human readable error code from the
+ * ustcomm_return_code enum.
  */
 const char *lttng_ust_strerror(int code);
 
diff --git a/liblttng-ust-comm/lttng-ust-comm.c b/liblttng-ust-comm/lttng-ust-comm.c
index 0b6aa293..8141ace3 100644
--- a/liblttng-ust-comm/lttng-ust-comm.c
+++ b/liblttng-ust-comm/lttng-ust-comm.c
@@ -70,19 +70,18 @@ static const char *ustcomm_readable_code[] = {
 
 /*
  * lttng_ust_strerror
+ * @code: must be a negative value of enum lttng_ust_error_code (or 0).
  *
- * Receives positive error value.
- * Return ptr to string representing a human readable
- * error code from the ustcomm_return_code enum.
+ * Returns a ptr to a string representing a human readable error code from the
+ * ustcomm_return_code enum.
  */
 const char *lttng_ust_strerror(int code)
 {
-	if (code == LTTNG_UST_OK)
-		return ustcomm_readable_code[USTCOMM_CODE_OFFSET(code)];
-	if (code < LTTNG_UST_ERR)
-		return strerror(code);
-	if (code >= LTTNG_UST_ERR_NR)
+	code = -code;
+
+	if (code < LTTNG_UST_OK || code >= LTTNG_UST_ERR_NR)
 		code = LTTNG_UST_ERR;
+
 	return ustcomm_readable_code[USTCOMM_CODE_OFFSET(code)];
 }