commit 7939382f7e2188b93a4a30957a73a4bae37a807b
author Varsha Kaverappa <vkaverap@in.ibm.com> Wed Aug 07 00:40:13 2024 -0500
committer Varsha Kaverappa <vkaverap@in.ibm.com> Thu Sep 19 01:41:47 2024 -0500
tree 47e4c80bf09935606aeed1a369195a4ac7a3867c
parent 6476c9685745feedf2bf7ccb63b466a1787d86c5

msgbuf: Allow pldm_msgbuf_span_required to accept NULL

Allow pldm_msgbuf_span_required to accept NULL as an argument
so we can use this API to skip past data in the msg buffer which
is not required and extract only the relevant data.

Change-Id: I08d233b8efe415732fb7c01c00a9925f04666fe2
Signed-off-by: Varsha Kaverappa <vkaverap@in.ibm.com>

src/msgbuf.h

diff --git a/src/msgbuf.h b/src/msgbuf.h
index 38c7055..6f50b05 100644
--- a/src/msgbuf.h
+++ b/src/msgbuf.h
@@ -1056,12 +1056,12 @@
 		char: pldm_msgbuf_insert_array_char)(dst, count, src,          \
 						     src_count)
 
-LIBPLDM_CC_NONNULL
+LIBPLDM_CC_NONNULL_ARGS(1)
 LIBPLDM_CC_ALWAYS_INLINE int pldm_msgbuf_span_required(struct pldm_msgbuf *ctx,
 						       size_t required,
 						       void **cursor)
 {
-	if (!ctx->cursor || *cursor) {
+	if (!ctx->cursor || (cursor && *cursor)) {
 		return pldm_msgbuf_status(ctx, EINVAL);
 	}
 
@@ -1080,7 +1080,9 @@
 		return pldm_msgbuf_status(ctx, EOVERFLOW);
 	}
 
-	*cursor = ctx->cursor;
+	if (cursor) {
+		*cursor = ctx->cursor;
+	}
 	ctx->cursor += required;
 
 	return 0;

tests/msgbuf.cpp

diff --git a/tests/msgbuf.cpp b/tests/msgbuf.cpp
index 111200a..7ddd2fb 100644
--- a/tests/msgbuf.cpp
+++ b/tests/msgbuf.cpp
@@ -873,6 +873,7 @@
     struct pldm_msgbuf* ctx = &_ctx;
     uint8_t src[6] = {0x11, 0x22, 0x44, 0x55, 0x66, 0x77};
     uint8_t buf[6] = {0};
+    const size_t required = 4;
     uint16_t testVal;
     [[maybe_unused]] uint8_t* retBuff = NULL;
 
@@ -887,6 +888,8 @@
     ASSERT_EQ(pldm_msgbuf_init_cc(ctxExtract, 0, buf, sizeof(buf)),
               PLDM_SUCCESS);
     EXPECT_EQ(pldm_msgbuf_extract_uint16(ctxExtract, &testVal), PLDM_SUCCESS);
+    EXPECT_EQ(pldm_msgbuf_span_required(ctxExtract, required, NULL),
+              PLDM_SUCCESS);
 
     EXPECT_EQ(pldm_msgbuf_destroy(ctxExtract), PLDM_SUCCESS);
     EXPECT_EQ(pldm_msgbuf_destroy(ctx), PLDM_SUCCESS);