Manually revert "Make COMPUTE_OFFSET and COMPUTE_OFFSET_AND_REMAINING macros."

This reverts commit b136182ad41b0552421992f36f3b70fa497fd658

This function are already marked inline, and profiler don't show much difference in performance,
revert as previous version is cleaner.

Change-Id: I1ac2c30a91b46278730ceee127efa086c7fbc6d6
Reviewed-on: https://code.wireshark.org/review/2828
Reviewed-by: Anders Broman <a.broman58@gmail.com>

1 files changed, 79 insertions, 85 deletions

diff --git a/epan/tvbuff.c b/epan/tvbuff.c
index b892ec8b36..1ad77b7cf9 100644
--- a/epan/tvbuff.c
+++ b/epan/tvbuff.c
@@ -164,59 +164,67 @@ tvb_add_to_chain(tvbuff_t *parent, tvbuff_t *child)
 	}
 }
 
-#define COMPUTE_OFFSET(tvb, offset, offset_ptr, exception) \
-	if (offset >= 0) { \
-		/* Positive offset - relative to the beginning of the packet. */ \
-		if ((guint) offset <= tvb->length) { \
-			*offset_ptr = offset; \
-		} else if ((guint) offset <= tvb->reported_length) { \
-			exception = BoundsError; \
-		} else if (tvb->flags & TVBUFF_FRAGMENT) { \
-			exception = FragmentBoundsError; \
-		} else { \
-			exception = ReportedBoundsError; \
-		} \
-	} \
-	else { \
-		/* Negative offset - relative to the end of the packet. */ \
-		if ((guint) -offset <= tvb->length) { \
-			*offset_ptr = tvb->length + offset; \
-		} else if ((guint) -offset <= tvb->reported_length) { \
-			exception =  BoundsError; \
-		} else if (tvb->flags & TVBUFF_FRAGMENT) { \
-			exception = FragmentBoundsError; \
-		} else { \
-			exception = ReportedBoundsError; \
-		} \
-	} \
-
-#define COMPUTE_OFFSET_AND_REMAINING(tvb, offset, offset_ptr, rem_len, exception) \
-	if (offset >= 0) { \
-		/* Positive offset - relative to the beginning of the packet. */ \
-		if ((guint) offset <= tvb->length) { \
-			*offset_ptr = offset; \
-		} else if ((guint) offset <= tvb->reported_length) { \
-			exception = BoundsError; \
-		} else if (tvb->flags & TVBUFF_FRAGMENT) { \
-			exception = FragmentBoundsError; \
-		} else { \
-			exception = ReportedBoundsError; \
-		} \
-	} \
-	else { \
-		/* Negative offset - relative to the end of the packet. */ \
-		if ((guint) -offset <= tvb->length) { \
-			*offset_ptr = tvb->length + offset; \
-		} else if ((guint) -offset <= tvb->reported_length) { \
-			exception =  BoundsError; \
-		} else if (tvb->flags & TVBUFF_FRAGMENT) { \
-			exception = FragmentBoundsError; \
-		} else { \
-			exception = ReportedBoundsError; \
-		} \
-	} \
-	if (!exception) \
-		rem_len = tvb->length - *offset_ptr; \
+/*
+ * Check whether that offset goes more than one byte past the
+ * end of the buffer.
+ *
+ * If not, return 0; otherwise, return exception
+ */
+static inline int
+validate_offset(const tvbuff_t *tvb, const guint abs_offset)
+{
+	if (G_LIKELY(abs_offset <= tvb->length))
+		return 0;
+	else if (abs_offset <= tvb->reported_length)
+		return BoundsError;
+	else if (tvb->flags & TVBUFF_FRAGMENT)
+		return FragmentBoundsError;
+	else
+		return ReportedBoundsError;
+}
+
+static inline int
+compute_offset(const tvbuff_t *tvb, const gint offset, guint *offset_ptr)
+{
+	if (offset >= 0) {
+		/* Positive offset - relative to the beginning of the packet. */
+		if ((guint) offset <= tvb->length) {
+			*offset_ptr = offset;
+		} else if ((guint) offset <= tvb->reported_length) {
+			return BoundsError;
+		} else if (tvb->flags & TVBUFF_FRAGMENT) {
+			return FragmentBoundsError;
+		} else {
+			return ReportedBoundsError;
+		}
+	}
+	else {
+		/* Negative offset - relative to the end of the packet. */
+		if ((guint) -offset <= tvb->length) {
+			*offset_ptr = tvb->length + offset;
+		} else if ((guint) -offset <= tvb->reported_length) {
+			return BoundsError;
+		} else if (tvb->flags & TVBUFF_FRAGMENT) {
+			return FragmentBoundsError;
+		} else {
+			return ReportedBoundsError;
+		}
+	}
+
+	return 0;
+}
+
+static inline int
+compute_offset_and_remaining(const tvbuff_t *tvb, const gint offset, guint *offset_ptr, guint *rem_len)
+{
+	int exception;
+
+	exception = compute_offset(tvb, offset, offset_ptr);
+	if (!exception)
+		*rem_len = tvb->length - *offset_ptr;
+
+	return exception;
+}
 
 /* Computes the absolute offset and length based on a possibly-negative offset
  * and a length that is possible -1 (which means "to the end of the data").
@@ -237,13 +245,13 @@ check_offset_length_no_exception(const tvbuff_t *tvb,
 				 guint *offset_ptr, guint *length_ptr)
 {
 	guint end_offset;
-	int   exception = 0;
+	int   exception;
 
 	DISSECTOR_ASSERT(offset_ptr);
 	DISSECTOR_ASSERT(length_ptr);
 
 	/* Compute the offset */
-	COMPUTE_OFFSET(tvb, offset, offset_ptr, exception);
+	exception = compute_offset(tvb, offset, offset_ptr);
 	if (exception)
 		return exception;
 
@@ -269,21 +277,7 @@ check_offset_length_no_exception(const tvbuff_t *tvb,
 	if (end_offset < *offset_ptr)
 		return BoundsError;
 
-	/*
-	 * Check whether that offset goes more than one byte past the
-	 * end of the buffer.
-	 *
-	 * If not, return 0; otherwise, return exception
-	 */
-	if (G_LIKELY(end_offset <= tvb->length))
-		return 0;
-	else if (end_offset <= tvb->reported_length)
-		return BoundsError;
-	else if (tvb->flags & TVBUFF_FRAGMENT)
-		return FragmentBoundsError;
-	else
-		return ReportedBoundsError;
-
+	return validate_offset(tvb, end_offset);
 }
 
 /* Checks (+/-) offset and length and throws an exception if
@@ -434,9 +428,9 @@ static inline gint
 _tvb_captured_length_remaining(const tvbuff_t *tvb, const gint offset)
 {
 	guint abs_offset, rem_length;
-	int   exception = 0;
+	int   exception;
 
-	COMPUTE_OFFSET_AND_REMAINING(tvb, offset, &abs_offset, rem_length, exception);
+	exception = compute_offset_and_remaining(tvb, offset, &abs_offset, &rem_length);
 	if (exception)
 		return 0;
 
@@ -447,11 +441,11 @@ gint
 tvb_captured_length_remaining(const tvbuff_t *tvb, const gint offset)
 {
 	guint abs_offset, rem_length;
-	int   exception = 0;
+	int   exception;
 
 	DISSECTOR_ASSERT(tvb && tvb->initialized);
 
-	COMPUTE_OFFSET_AND_REMAINING(tvb, offset, &abs_offset, rem_length, exception);
+	exception = compute_offset_and_remaining(tvb, offset, &abs_offset, &rem_length);
 	if (exception)
 		return 0;
 
@@ -462,11 +456,11 @@ guint
 tvb_ensure_captured_length_remaining(const tvbuff_t *tvb, const gint offset)
 {
 	guint abs_offset, rem_length;
-	int   exception = 0;
+	int   exception;
 
 	DISSECTOR_ASSERT(tvb && tvb->initialized);
 
-	COMPUTE_OFFSET_AND_REMAINING(tvb, offset, &abs_offset, rem_length, exception);
+	exception = compute_offset_and_remaining(tvb, offset, &abs_offset, &rem_length);
 	if (exception)
 		THROW(exception);
 
@@ -585,19 +579,19 @@ tvb_ensure_bytes_exist(const tvbuff_t *tvb, const gint offset, const gint length
 gboolean
 tvb_offset_exists(const tvbuff_t *tvb, const gint offset)
 {
-	guint offset_ptr;
-	int   exception = 0;
+	guint abs_offset;
+	int   exception;
 
 	DISSECTOR_ASSERT(tvb && tvb->initialized);
 
-	COMPUTE_OFFSET(tvb, offset, &offset_ptr, exception);
+	exception = compute_offset(tvb, offset, &abs_offset);
 	if (exception)
 		return FALSE;
 
 	/* compute_offset only throws an exception on >, not >= because of the
 	 * comment above check_offset_length_no_exception, but here we want the
 	 * opposite behaviour so we check ourselves... */
-	if (offset_ptr < tvb->length) {
+	if (abs_offset < tvb->length) {
 		return TRUE;
 	}
 	else {
@@ -616,17 +610,17 @@ tvb_reported_length(const tvbuff_t *tvb)
 gint
 tvb_reported_length_remaining(const tvbuff_t *tvb, const gint offset)
 {
-	guint offset_ptr;
-	int   exception = 0;
+	guint abs_offset;
+	int   exception;
 
 	DISSECTOR_ASSERT(tvb && tvb->initialized);
 
-	COMPUTE_OFFSET(tvb, offset, &offset_ptr, exception);
+	exception = compute_offset(tvb, offset, &abs_offset);
 	if (exception)
 		return 0;
 
-	if (tvb->reported_length >= offset_ptr)
-		return tvb->reported_length - offset_ptr;
+	if (tvb->reported_length >= abs_offset)
+		return tvb->reported_length - abs_offset;
 	else
 		return 0;
 }