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Use a union for pointer polymorphism in the .slvs file I/O routines 

The .slvs file I/O code was using "*((type *)pointer) = value" type-punning
dereferences, which are syntactically unwieldy and prone to annoying modern
compilers. A union pointer is more elegant, and better expresses the
polymorphism at issue.
pull/3/head
Daniel Richard G 2013-11-13 00:46:40 -05:00
parent 442197c907
commit 5429295492
1 changed files with 35 additions and 27 deletions
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62
file.cpp
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@ -201,35 +201,45 @@ const SolveSpace::SaveTable SolveSpace::SAVED[] = {
{ 0, NULL, 0, NULL } { 0, NULL, 0, NULL }
}; };
union SAVEDptr {
IdList<EntityMap,EntityId> M;
NameStr N;
char P;
bool b;
RgbColor c;
int d;
double f;
uint32_t x;
};
void SolveSpace::SaveUsingTable(int type) { void SolveSpace::SaveUsingTable(int type) {
int i; int i;
for(i = 0; SAVED[i].type != 0; i++) { for(i = 0; SAVED[i].type != 0; i++) {
if(SAVED[i].type != type) continue; if(SAVED[i].type != type) continue;
int fmt = SAVED[i].fmt; int fmt = SAVED[i].fmt;
void *p = SAVED[i].ptr; union SAVEDptr *p = (union SAVEDptr *)SAVED[i].ptr;
// Any items that aren't specified are assumed to be zero // Any items that aren't specified are assumed to be zero
if(fmt == 'd' && *((int *)p) == 0) continue; if(fmt == 'N' && p->N.str == '\0') continue;
if(fmt == 'x' && *((uint32_t *)p) == 0) continue; if(fmt == 'd' && p->d == 0) continue;
if(fmt == 'f' && *((double *)p) == 0.0) continue; if(fmt == 'f' && EXACT(p->f == 0.0)) continue;
if(fmt == 'N' && strlen(((NameStr *)p)->str) == 0) continue; if(fmt == 'x' && p->x == 0) continue;
fprintf(fh, "%s=", SAVED[i].desc); fprintf(fh, "%s=", SAVED[i].desc);
switch(fmt) { switch(fmt) {
case 'd': fprintf(fh, "%d", *((int *)p)); break; case 'N': fprintf(fh, "%s", p->N.str); break;
case 'b': fprintf(fh, "%d", *((bool *)p) ? 1 : 0); break; case 'P': fprintf(fh, "%s", &(p->P)); break;
case 'x': fprintf(fh, "%08x", *((uint32_t *)p)); break; case 'b': fprintf(fh, "%d", p->b ? 1 : 0); break;
case 'f': fprintf(fh, "%.20f", *((double *)p)); break; case 'c': fprintf(fh, "%08x", p->c.ToPackedInt()); break;
case 'N': fprintf(fh, "%s", ((NameStr *)p)->str); break; case 'd': fprintf(fh, "%d", p->d); break;
case 'c': fprintf(fh, "%08x", ((RgbColor *)p)->ToPackedInt());break; case 'f': fprintf(fh, "%.20f", p->f); break;
case 'P': fprintf(fh, "%s", (char *)p); break; case 'x': fprintf(fh, "%08x", p->x); break;
case 'M': { case 'M': {
int j; int j;
fprintf(fh, "{\n"); fprintf(fh, "{\n");
IdList<EntityMap,EntityId> *m = (IdList<EntityMap,EntityId> *)p; for(j = 0; j < p->M.n; j++) {
for(j = 0; j < m->n; j++) { EntityMap *em = &(p->M.elem[j]);
EntityMap *em = &(m->elem[j]);
fprintf(fh, " %d %08x %d\n", fprintf(fh, " %d %08x %d\n",
em->h.v, em->input.v, em->copyNumber); em->h.v, em->input.v, em->copyNumber);
} }
@ -360,32 +370,30 @@ void SolveSpace::LoadUsingTable(char *key, char *val) {
int i; int i;
for(i = 0; SAVED[i].type != 0; i++) { for(i = 0; SAVED[i].type != 0; i++) {
if(strcmp(SAVED[i].desc, key)==0) { if(strcmp(SAVED[i].desc, key)==0) {
void *p = SAVED[i].ptr; union SAVEDptr *p = (union SAVEDptr *)SAVED[i].ptr;
unsigned int u = 0; unsigned int u = 0;
switch(SAVED[i].fmt) { switch(SAVED[i].fmt) {
case 'd': *((int *)p) = atoi(val); break; case 'N': p->N.strcpy(val); break;
case 'b': *((bool *)p) = (atoi(val) != 0); break; case 'b': p->b = (atoi(val) != 0); break;
case 'x': sscanf(val, "%x", &u); *((uint32_t *)p) = u; break; case 'd': p->d = atoi(val); break;
case 'f': *((double *)p) = atof(val); break; case 'f': p->f = atof(val); break;
case 'N': ((NameStr *)p)->strcpy(val); break; case 'x': sscanf(val, "%x", &u); p->x = u; break;
case 'c': case 'c':
sscanf(val, "%x", &u); sscanf(val, "%x", &u);
*((RgbColor *)p) = RgbColor::FromPackedInt(u); p->c = RgbColor::FromPackedInt(u);
break; break;
case 'P': case 'P':
if(strlen(val)+1 < MAX_PATH) strcpy((char *)p, val); if(strlen(val)+1 < MAX_PATH) strcpy(&(p->P), val);
break; break;
case 'M': { case 'M': {
IdList<EntityMap,EntityId> *m =
(IdList<EntityMap,EntityId> *)p;
// Don't clear this list! When the group gets added, it // Don't clear this list! When the group gets added, it
// makes a shallow copy, so that would result in us // makes a shallow copy, so that would result in us
// freeing memory that we want to keep around. Just // freeing memory that we want to keep around. Just
// zero it out so that new memory is allocated. // zero it out so that new memory is allocated.
memset(m, 0, sizeof(*m)); memset(&(p->M), 0, sizeof(p->M));
for(;;) { for(;;) {
EntityMap em; EntityMap em;
char line2[1024]; char line2[1024];
@ -394,7 +402,7 @@ void SolveSpace::LoadUsingTable(char *key, char *val) {
if(sscanf(line2, "%d %x %d", &(em.h.v), &(em.input.v), if(sscanf(line2, "%d %x %d", &(em.h.v), &(em.input.v),
&(em.copyNumber)) == 3) &(em.copyNumber)) == 3)
{ {
m->Add(&em); p->M.Add(&em);
} else { } else {
break; break;
} }