Don't use "== {TRUE,FALSE}" when testing whether a Boolean is true or false.

"if (boolean)" suffices to test for true, and "if (!boolean)" suffices
to test for false.

Most of the time, explicitly comparing against TRUE or FALSE is
harmless, although possibly slightly less efficient, as you're
explicitly testing against 1 rather than testing for "not zero".

*However*, if you want to test whether a given bit is set in a flags
field, "if ((flags & flagbit) == TRUE)" *DOES NOT WORK* unless "flagbit"
is equal to 1, because TRUE is equal to 1, and if "flagbit" is not equal
to 1, "flags & flagbit" will *NEVER* be equal to 1.

So comparing "== TRUE" is a bad habit to get into, as it might lead to
its use when doing bit testing.

While we're at it, clean up some other tests:

	"if (!(x == FALSE))" really means "x is true", so write it as
	such, i.e. "if (x)";

		if (a && b)
			do this;
		if (a && !b)
			do that;

	reads better as

		if (a) {
			if (b)
				do this
			else
				do that
		}

	when doing bit testing, there's no need to shift the bit, just
	test it (and, no, that doesn't conflict with the bit about TRUE
	being 1 - *just test the bit*, it's the standard C idiom).

Fixes CID 1362119.

Change-Id: I011154caae45307796ffd270d265c05a2533b1db
Reviewed-on: https://code.wireshark.org/review/15585
Reviewed-by: Guy Harris <guy@alum.mit.edu>

1 files changed, 30 insertions, 28 deletions

diff --git a/plugins/profinet/packet-dcerpc-pn-io.c b/plugins/profinet/packet-dcerpc-pn-io.c
index 1dc9ad79b9..11ba68cc6e 100644
--- a/plugins/profinet/packet-dcerpc-pn-io.c
+++ b/plugins/profinet/packet-dcerpc-pn-io.c
@@ -7313,7 +7313,7 @@ dissect_IOCRBlockReq_block(tvbuff_t *tvb, int offset,
 
         /* Set global Variant for Number of IO Data Objects */
         /* Notice: Handle Input & Output seperate!!! */
-        if (pinfo->fd->flags.visited == FALSE) {
+        if (!pinfo->fd->flags.visited) {
             /* Get current conversation endpoints using MAC addresses */
             conversation = find_conversation(pinfo->num, &pinfo->dl_src, &pinfo->dl_dst, PT_NONE, 0, 0, 0);
             if (conversation == NULL) {
@@ -7355,7 +7355,7 @@ dissect_IOCRBlockReq_block(tvbuff_t *tvb, int offset,
 
             proto_item_set_len(sub_item, offset - u32SubStart);
 
-            if (pinfo->fd->flags.visited == FALSE && station_info != NULL) {
+            if (!pinfo->fd->flags.visited && station_info != NULL) {
                 io_data_object = wmem_new(wmem_file_scope(), ioDataObject);
                 io_data_object->slotNr = u16SlotNr;
                 io_data_object->subSlotNr = u16SubslotNr;
@@ -7397,7 +7397,7 @@ dissect_IOCRBlockReq_block(tvbuff_t *tvb, int offset,
                             hf_pn_io_number_of_iocs, &u16NumberOfIOCS);
 
         /* Set global Vairant for NumberOfIOCS */
-        if (pinfo->fd->flags.visited == FALSE) {
+        if (!pinfo->fd->flags.visited) {
             if (station_info != NULL) {
                 station_info->iocsNr = u16NumberOfIOCS;
             }
@@ -7424,7 +7424,7 @@ dissect_IOCRBlockReq_block(tvbuff_t *tvb, int offset,
 
             proto_item_set_len(sub_item, offset - u32SubStart);
 
-            if (pinfo->fd->flags.visited == FALSE) {
+            if (!pinfo->fd->flags.visited) {
                 if (station_info != NULL) {
                     if (u16IOCRType == PN_INPUT_CR) {
                         iocs_list = station_info->iocs_data_in;
@@ -8047,7 +8047,7 @@ dissect_DataDescription(tvbuff_t *tvb, int offset,
     proto_item_set_len(sub_item, offset - u32SubStart);
 
     /* Save new data for IO Data Objects */
-    if (pinfo->fd->flags.visited == FALSE) {
+    if (!pinfo->fd->flags.visited) {
         /* Get current conversation endpoints using MAC addresses */
         conversation = find_conversation(pinfo->num, &pinfo->dl_src, &pinfo->dl_dst, PT_NONE, 0, 0, 0);
         if (conversation == NULL) {
@@ -8242,7 +8242,7 @@ dissect_ExpectedSubmoduleBlockReq_block(tvbuff_t *tvb, int offset,
                             fp = NULL;
                         }
 
-                        if(vendorMatch == TRUE && deviceMatch == TRUE) {
+                        if(vendorMatch && deviceMatch) {
                             break;        /* Found correct GSD-file! -> Break the searchloop */
                         }
                         else {
@@ -8259,7 +8259,7 @@ dissect_ExpectedSubmoduleBlockReq_block(tvbuff_t *tvb, int offset,
             }
 
             /* ---- Found the correct GSD-file -> set Flag and save the completed path ---- */
-            if((vendorMatch == TRUE) && (deviceMatch == TRUE)) {
+            if(vendorMatch && deviceMatch) {
                 gsdmlFoundFlag = TRUE;
                 station_info->gsdFound = TRUE;
                 station_info->gsdLocation = wmem_strdup(wmem_file_scope(), diropen);
@@ -8351,7 +8351,7 @@ dissect_ExpectedSubmoduleBlockReq_block(tvbuff_t *tvb, int offset,
             if (diropen != NULL) {
                 fp = ws_fopen(diropen, "r");
             }
-            if(gsdmlFoundFlag == TRUE && fp != NULL) {
+            if(gsdmlFoundFlag && fp != NULL) {
                 fseek(fp, 0, SEEK_SET);
 
                 /* Find Indexnumber for fParameter */
@@ -8552,7 +8552,7 @@ dissect_ModuleDiffBlock_block(tvbuff_t *tvb, int offset,
                 u16NumberOfSubmodules);
 
 
-            if (pinfo->fd->flags.visited == FALSE) {
+            if (!pinfo->fd->flags.visited) {
                 /* Get current conversation endpoints using MAC addresses */
                 conversation = find_conversation(pinfo->num, &pinfo->dl_src, &pinfo->dl_dst, PT_NONE, 0, 0, 0);
                 if (conversation == NULL) {
@@ -9802,7 +9802,7 @@ dissect_ProfiSafeParameterRequest(tvbuff_t *tvb, int offset,
                     hf_pn_io_ps_f_wd_time, &wd_time);
 
     /* Dissection for F_iPar_CRC: see F_Prm_Flag2 -> F_Block_ID */
-    if( ((prm_flag2_f_block_id & 0x08)>>3) == TRUE && ((prm_flag2_f_block_id & 0x20)>>5) == FALSE ) {
+    if( (prm_flag2_f_block_id & 0x08) && !(prm_flag2_f_block_id & 0x20) ) {
         offset = dissect_dcerpc_uint32(tvb, offset, pinfo, f_item, drep,
                         hf_pn_io_ps_f_ipar_crc, &ipar_crc);
     }
@@ -9812,7 +9812,7 @@ dissect_ProfiSafeParameterRequest(tvbuff_t *tvb, int offset,
 
 
     /* Differniate between ipar_crc and no_ipar_crc */
-    if( ((prm_flag2_f_block_id & 0x08)>>3) == TRUE && ((prm_flag2_f_block_id & 0x20)>>5) == FALSE ) {    /* include ipar_crc display */
+    if( (prm_flag2_f_block_id & 0x08) && !(prm_flag2_f_block_id & 0x20) ) {    /* include ipar_crc display */
         col_append_fstr(pinfo->cinfo, COL_INFO,
                         ", F-Parameter record, prm_flag1:0x%02x, prm_flag2:0x%02x, src:0x%04x,"
                          " dst:0x%04x, wd_time:%d, ipar_crc:0x%04x, crc:0x%04x",
@@ -9831,7 +9831,7 @@ dissect_ProfiSafeParameterRequest(tvbuff_t *tvb, int offset,
                 prm_flag1, prm_flag2, src_addr, dst_addr, wd_time, par_crc);
     }
 
-    if (pinfo->fd->flags.visited == FALSE) {
+    if (!pinfo->fd->flags.visited) {
         /* Get current conversation endpoints using MAC addresses */
         conversation = find_conversation(pinfo->num, &pinfo->dl_src, &pinfo->dl_dst, PT_NONE, 0, 0, 0);
         if (conversation == NULL) {
@@ -9847,11 +9847,12 @@ dissect_ProfiSafeParameterRequest(tvbuff_t *tvb, int offset,
                 io_data_object->f_src_adr = src_addr;
                 io_data_object->f_dest_adr = dst_addr;
                 io_data_object->f_crc_seed = prm_flag1 & 0x40;
-                if ((prm_flag1 & 0x10) == FALSE && (prm_flag1 & 0x20) == FALSE) {
-                    io_data_object->f_crc_len = 3;
-                }
-                if ((prm_flag1 & 0x10) == FALSE && (prm_flag1 & 0x20) == TRUE) {
-                    io_data_object->f_crc_len = 4;
+                if (!(prm_flag1 & 0x10)) {
+                    if (prm_flag1 & 0x20) {
+                        io_data_object->f_crc_len = 4;
+                    } else {
+                        io_data_object->f_crc_len = 3;
+                    }
                 }
             }
 
@@ -9859,18 +9860,19 @@ dissect_ProfiSafeParameterRequest(tvbuff_t *tvb, int offset,
             for (frame_out = wmem_list_head(station_info->ioobject_data_out); frame_out != NULL; frame_out = wmem_list_frame_next(frame_out)) {
                 io_data_object = (ioDataObject*)wmem_list_frame_data(frame_out);
                 if (u16Index == io_data_object->fParameterIndexNr &&    /* Check F-Parameter Indexnumber */
-                    io_data_object->profisafeSupported == TRUE &&       /* Arrayelement has to be PS-Module */
+                    io_data_object->profisafeSupported &&               /* Arrayelement has to be PS-Module */
                     io_data_object->f_par_crc1 == 0) {                  /* Find following object with no f_par_crc1 */
 
                     io_data_object->f_par_crc1 = par_crc;
                     io_data_object->f_src_adr = src_addr;
                     io_data_object->f_dest_adr = dst_addr;
                     io_data_object->f_crc_seed = prm_flag1 & 0x40;
-                    if ((prm_flag1 & 0x10) == FALSE && (prm_flag1 & 0x20) == FALSE) {
-                        io_data_object->f_crc_len = 3;
-                    }
-                    if ((prm_flag1 & 0x10) == FALSE && (prm_flag1 & 0x20) == TRUE) {
-                        io_data_object->f_crc_len = 4;
+                    if (!(prm_flag1 & 0x10)) {
+                        if (prm_flag1 & 0x20) {
+                            io_data_object->f_crc_len = 4;
+                        } else {
+                            io_data_object->f_crc_len = 3;
+                        }
                     }
 
                     break;
@@ -9903,12 +9905,12 @@ dissect_RecordDataWrite(tvbuff_t *tvb, int offset,
 
     station_info = (stationInfo*)conversation_get_proto_data(conversation, proto_pn_dcp);
     if (station_info != NULL) {
-        if (pinfo->fd->flags.visited == FALSE) {
+        if (!pinfo->fd->flags.visited) {
             /* Search within the entire existing list for current input object data */
             for (frame = wmem_list_head(station_info->ioobject_data_in); frame != NULL; frame = wmem_list_frame_next(frame)) {
                 io_data_object = (ioDataObject*)wmem_list_frame_data(frame);
                 if (u16Index == io_data_object->fParameterIndexNr &&    /* Check F-Parameter Indexnumber */
-                    io_data_object->profisafeSupported == TRUE &&       /* Arrayelement has to be PS-Module */
+                    io_data_object->profisafeSupported &&               /* Arrayelement has to be PS-Module */
                     io_data_object->f_par_crc1 == 0) {                  /* Find following object with no f_par_crc1 */
 
                     return dissect_ProfiSafeParameterRequest(tvb, offset, pinfo, tree, drep, u16Index, frame);
@@ -9923,7 +9925,7 @@ dissect_RecordDataWrite(tvbuff_t *tvb, int offset,
             for (frame = wmem_list_head(station_info->ioobject_data_in); frame != NULL; frame = wmem_list_frame_next(frame)) {
                 io_data_object = (ioDataObject*)wmem_list_frame_data(frame);
                 if (u16Index == io_data_object->fParameterIndexNr &&    /* Check F-Parameter Indexnumber */
-                    io_data_object->profisafeSupported == TRUE) {       /* Arrayelement has to be PS-Module */
+                    io_data_object->profisafeSupported) {               /* Arrayelement has to be PS-Module */
 
                     return dissect_ProfiSafeParameterRequest(tvb, offset, pinfo, tree, drep, u16Index, frame);
                 }
@@ -9932,7 +9934,7 @@ dissect_RecordDataWrite(tvbuff_t *tvb, int offset,
             for (frame = wmem_list_head(station_info->ioobject_data_out); frame != NULL; frame = wmem_list_frame_next(frame)) {
                 io_data_object = (ioDataObject*)wmem_list_frame_data(frame);
                 if (u16Index == io_data_object->fParameterIndexNr &&    /* Check F-Parameter Indexnumber */
-                    io_data_object->profisafeSupported == TRUE) {       /* Arrayelement has to be PS-Module */
+                    io_data_object->profisafeSupported) {               /* Arrayelement has to be PS-Module */
 
                     return dissect_ProfiSafeParameterRequest(tvb, offset, pinfo, tree, drep, u16Index, frame);
                 }
@@ -10137,7 +10139,7 @@ dissect_PNIO_C_SDU(tvbuff_t *tvb, int offset,
     }
 
     /*dissect_dcerpc_uint16(tvb, offset, pinfo, data_tree, drep, hf_pn_io_packedframe_SFCRC, &u16SFCRC);*/
-    if (!(dissect_CSF_SDU_heur(tvb, pinfo, data_tree, NULL) == FALSE))
+    if (dissect_CSF_SDU_heur(tvb, pinfo, data_tree, NULL))
         return(tvb_captured_length(tvb));
 
     /* XXX - dissect the remaining data */