Avoid a DNA parsing bug that would parse "float gravity [3];" as two

struct members "gravity" and "[3]". Now it throws an error in this case,
safer than trying to fix the parsing code. Also patches the old DNA of
ClothSimSettings which had this problem .. very ugly code.

Fixes #20330: cloth sim settings getting corrupted when read from 2.49.

3 files changed, 28 insertions, 7 deletions

diff --git a/source/blender/makesdna/DNA_cloth_types.h b/source/blender/makesdna/DNA_cloth_types.h
index 777c2ec8747..06ace29dbfe 100644
--- a/source/blender/makesdna/DNA_cloth_types.h
+++ b/source/blender/makesdna/DNA_cloth_types.h
@@ -47,10 +47,7 @@ typedef struct ClothSimSettings
 	float 	mingoal; 	/* see SB */
 	float	Cdis;		/* Mechanical damping of springs.		*/
 	float	Cvi;		/* Viscous/fluid damping.			*/
-	/* XXX the extra space here results in wrong DNA parsing,
-	 * and reconstruct fails and gives corrupt settings when
-	 * removing it because the old dna is wrong ... */
-	float	gravity [3];	/* Gravity/external force vector.		*/
+	float	gravity[3];	/* Gravity/external force vector.		*/
 	float	dt;		/* This is the duration of our time step, computed.	*/
 	float	mass;		/* The mass of the entire cloth.		*/
 	float	structural;	/* Structural spring stiffness.			*/
@@ -79,6 +76,7 @@ typedef struct ClothSimSettings
 	short	vgroup_struct;  /* vertex group for scaling structural stiffness */
 	short	presets; /* used for presets on GUI */
  	short 	reset;
+	int		pad;
 
 	struct EffectorWeights *effector_weights;
 } ClothSimSettings;
diff --git a/source/blender/makesdna/intern/dna_genfile.c b/source/blender/makesdna/intern/dna_genfile.c
index cbc433ed722..89219b114da 100644
--- a/source/blender/makesdna/intern/dna_genfile.c
+++ b/source/blender/makesdna/intern/dna_genfile.c
@@ -297,7 +297,7 @@ int DNA_struct_find_nr(SDNA *sdna, const char *str)
 static void init_structDNA(SDNA *sdna, int do_endian_swap)
 /* in sdna->data the data, now we convert that to something understandable */
 {
-	int *data, *verg;
+	int *data, *verg, gravity_fix= -1;
 	intptr_t nr;
 	short *sp;
 	char str[8], *cp;
@@ -330,6 +330,17 @@ static void init_structDNA(SDNA *sdna, int do_endian_swap)
 		cp= (char *)data;
 		while(nr<sdna->nr_names) {
 			sdna->names[nr]= cp;
+
+			/* "float gravity [3]" was parsed wrong giving both "gravity" and
+			   "[3]"  members. we rename "[3]", and later set the type of
+			   "gravity" to "void" so the offsets work out correct */
+			if(*cp == '[' && strcmp(cp, "[3]")==0) {
+				if(nr && strcmp(sdna->names[nr-1], "Cvi") == 0) {
+					sdna->names[nr]= "gravity[3]";
+					gravity_fix= nr;
+				}
+			}
+
 			while( *cp) cp++;
 			cp++;
 			nr++;
@@ -444,7 +455,7 @@ static void init_structDNA(SDNA *sdna, int do_endian_swap)
 			
 			nr++;
 		}
-		
+
 		/* finally pointerlen: use struct ListBase to test it, never change the size of it! */
 		sp= findstruct_name(sdna, "ListBase");
 		/* weird; i have no memory of that... I think I used sizeof(void *) before... (ton) */
@@ -457,6 +468,14 @@ static void init_structDNA(SDNA *sdna, int do_endian_swap)
 			/* well, at least sizeof(ListBase) is error proof! (ton) */
 		}
 		
+		/* second part of gravity problem, setting "gravity" type to void */
+		if(gravity_fix > -1) {
+			for(nr=0; nr<sdna->nr_structs; nr++) {
+				sp= sdna->structs[nr];
+				if(strcmp(sdna->types[sp[0]], "ClothSimSettings") == 0)
+					sp[10]= 9;
+			}
+		}
 	}
 }
 
diff --git a/source/blender/makesdna/intern/makesdna.c b/source/blender/makesdna/intern/makesdna.c
index 4ccabc95a32..2d62b81e81b 100644
--- a/source/blender/makesdna/intern/makesdna.c
+++ b/source/blender/makesdna/intern/makesdna.c
@@ -699,7 +699,7 @@ static int calculate_structlens(int firststruct)
 				for(b=0; b<structpoin[1]; b++, sp+=2) {
 					type= sp[0];
 					cp= names[sp[1]];
-					
+
 					namelen= (int) strlen(cp);
 					/* is it a pointer or function pointer? */
 					if(cp[0]=='*' || cp[1]=='*') {
@@ -729,6 +729,10 @@ static int calculate_structlens(int firststruct)
 						len += sizeof(void *) * mul;
 						alphalen += 8 * mul;
 
+					} else if(cp[0]=='[') {
+						/* parsing can cause names "var" and "[3]" to be found for "float var [3]" ... */
+						printf("Parse error in struct, invalid member name: %s %s\n", types[structtype], cp);
+						dna_error = 1;
 					} else if( typelens[type] ) {
 						/* has the name an extra length? (array) */
 						mul= 1;