src/rt/RcontribSimulManager.cpp

#ifndef lint
static const char RCSid[] = "$Id: RcontribSimulManager.cpp,v 2.23 2025/11/11 02:08:52 greg Exp $";
#endif
/*
 *  RcontribSimulManager.cpp
 *
 *      Rcontrib simulation manager implementation
 *
 *  Created by Greg Ward on 10/17/2024.
 */

#include <unistd.h>
#include <ctype.h>
#include "platform.h"
#include "selcall.h"
#include "RcontribSimulManager.h"
#include "func.h"
#include "resolu.h"
#include "source.h"

char                    RCCONTEXT[] = "RC.";

extern const char       HDRSTR[];
extern const char       BIGEND[];
extern const char       FMTSTR[];

// new/exclusive, overwrite if exists, or recover data
int     RSDOflags[] = {RDSwrite|RDSexcl|RDSextend, RDSwrite|RDSextend,
                                RDSread|RDSwrite};

static const char       ROWZEROSTR[] = "NROWS=0000000000000000\n";
#define LNROWSTR        6

// Modifier channel for recording contributions (no constructor/destructor)
struct RcontribMod {
        RcontribOutput *        opl;            // pointer to first output channel
        char *                  params;         // parameters string
        EPNODE *                binv;           // bin expression (NULL if 1 bin)
        int                     nbins;          // bin count this modifier
        int                     coffset;        // column offset in bytes
        DCOLORV                 cbin[1];        // bin accumulator (extends struct)
                                /// Access specific (spectral) color bin
        DCOLORV *               operator[](int n) {
                                        if ((n < 0) | (n >= nbins)) return NULL;
                                        return cbin + n*NCSAMP;
                                }
};

// Struct used to assign record calculation to child
struct RowAssignment {
        uint32                  row;            // row to do
        uint32                  ac;             // accumulation count
};

static const char       ROW_DONE[] = "ROW FINISHED\n";

// allocate rcontrib accumulator
static RcontribMod *
NewRcMod(const char *prms, const char *binexpr, int ncbins)
{
        if (binexpr && !*binexpr) binexpr = NULL;
        if (!prms) prms = "";
        if ((ncbins > 1) & !binexpr) {
                error(USER, "missing bin expression");
                return NULL;
        }
        if (ncbins < 1) ncbins = 1;
        
        RcontribMod *   mp = (RcontribMod *)ecalloc(1, sizeof(RcontribMod) +
                                                sizeof(DCOLORV)*(NCSAMP*ncbins-1) +
                                                strlen(prms)+1);

        if (binexpr) {                          // get/check bin expression
                mp->binv = eparse(const_cast<char *>(binexpr));
                if (mp->binv->type == NUM) {    // constant expression (0)?
                        if ((int)evalue(mp->binv) != 0) {
                                sprintf(errmsg, "illegal non-zero constant for bin (%s)",
                                                binexpr);
                                error(USER, errmsg);
                        }
                        if (ncbins > 1) {
                                sprintf(errmsg, "bad bin count (%d should be 1)", ncbins);
                                error(USER, errmsg);
                        }
                        epfree(mp->binv, true);
                        mp->binv = NULL;
                        prms = "";
                        ncbins = 1;
                }
        }
        mp->params = strcpy((char *)(mp->cbin + ncbins*NCSAMP), prms);
        mp->nbins = ncbins;
        return mp;
}

// Free an RcontribMod (public for RcontribSimulManager constructor)
void
FreeRcMod(void *p)
{
        if (!p) return;
        EPNODE *        bep = (*(RcontribMod *)p).binv;
        if (bep) epfree(bep, true);
        efree(p);
}

// Get format identifier
const char *
formstr(int f)
{
        switch (f) {
        case 'a': return("ascii");
        case 'f': return("float");
        case 'd': return("double");
        case 'c': return(NCSAMP==3 ? COLRFMT : SPECFMT);
        }
        return("unknown");
}

// Standard file data share function
RdataShare *
fileDataShare(const char *name, RCOutputOp op, size_t siz)
{
        if (op == RCOrecover && access(name, R_OK|W_OK) < 0) {
                sprintf(errmsg, "cannot recover from '%s'", name);
                error(SYSTEM, errmsg);
                return NULL;
        }
        RdataShare *    rds = new RdataShareFile(name, RSDOflags[op],
                                                 siz*(op != RCOforce));
                                                 
        if (!rds || (op == RCOforce && rds->Resize(siz) < siz)) {
                delete rds;
                sprintf(errmsg, "cannot create %lu byte output file '%s'",
                                        (unsigned long)siz, name);
                error(SYSTEM, errmsg);
                return NULL;
        }
        return rds;
}

// Memory-mapped data share function
RdataShare *
mapDataShare(const char *name, RCOutputOp op, size_t siz)
{
        if (op == RCOrecover && access(name, R_OK|W_OK) < 0) {
                sprintf(errmsg, "cannot recover from '%s'", name);
                error(SYSTEM, errmsg);
                return NULL;
        }
        RdataShare *    rds = new RdataShareMap(name, RSDOflags[op],
                                                 siz*(op != RCOforce));

        if (!rds || (op == RCOforce && rds->Resize(siz) < siz)) {
                delete rds;
                sprintf(errmsg, "cannot create %lu byte output map '%s'",
                                        (unsigned long)siz, name);
                error(SYSTEM, errmsg);
                return NULL;
        }
        return rds;
}

// Set output format ('f', 'd', or 'c')
bool
RcontribSimulManager::SetDataFormat(int ty)
{
        if (outList) {
                error(INTERNAL, "cannot call SetDataFormat() after AddModifier()");
                return false;
        }
        switch (ty) {
        case 'f':
                dsiz = sizeof(float)*NCSAMP;
                break;
        case 'd':
                dsiz = sizeof(double)*NCSAMP;
                break;
        case 'c':
                dsiz = LSCOLR;
                break;
        default:
                sprintf(errmsg, "unsupported output format '%c'", ty);
                error(INTERNAL, errmsg);
                return false;
        }
        dtyp = ty;
        return true;
}

// static call-back for rcontrib ray-tracing
int
RcontribSimulManager::RctCall(RAY *r, void *cd)
{
        int     i;

        if (!r->ro || (i = r->ro->omod) == OVOID)
                return 0;               // hit nothing

        if (r->rsrc >= 0 && source[r->rsrc].so != r->ro)
                return 0;               // shadow ray not on source

        const char *            mname = objptr(i)->oname;
        RcontribSimulManager *  rcp = (RcontribSimulManager *)cd;
        RcontribMod *           mp = (RcontribMod *)lu_find(&rcp->modLUT,mname)->data;
        if (!mp)
                return 0;               // not in our modifier list

        if (rcp->HasFlag(RCcontrib)) {  // pre-emptive check for zero
                for (i = NCSAMP; i--; )
                        if (r->rcoef[i]*r->rcol[i] > FTINY)
                                break;
                if (i < 0)
                        return 0;       // zero contribution
        } else if (sintens(r->rcoef) <= FTINY)
                return 0;               // zero coefficient

        int     bi = 0;                 // get bin index
        if (mp->binv) {
                worldfunc(RCCONTEXT, r);
                set_eparams(mp->params);
                double          bval = evalue(mp->binv);
                if (bval <= -.5)
                        return 0;       // silently ignore negative bin index
                bi = int(bval + .5);
        }
        DCOLORV *       dvp = (*mp)[bi];
        if (!dvp) {
                sprintf(errmsg, "bad bin number for '%s' (%d ignored)", mname, bi);
                error(WARNING, errmsg);
                return 0;
        }
        SCOLOR          contr;
        raycontrib(contr, r, PRIMARY);          // compute coefficient
        if (rcp->HasFlag(RCcontrib))
                smultscolor(contr, r->rcol);    // -> value contribution

        for (i = 0; i < NCSAMP; i++)
                *dvp++ += contr[i];             // accumulate color/spectrum
        return 1;
}

// check for given format type in string, return last char position
static int
hasFormat(const char *tst, const char *match)
{
        static const char       allPoss[] = "%diouxXfFeEgGaAcsb";
        const char *            s = tst;
        while (*s) {
                if (*s++ != '%')
                        continue;
                while (!strchr(allPoss, *s))
                        s++;
                if (strchr(match, *s))
                        break;
                s++;
        }
        return (*s != '\0')*(s - tst);
}

// Add a modifier and arguments, opening output file(s)
bool
RcontribSimulManager::AddModifier(const char *modn, const char *outspec,
                                const char *prms, const char *binval, int bincnt)
{
        if (!modn | !outspec || !*modn | !*outspec) {
                error(WARNING, "ignoring bad call to AddModifier()");
                return false;
        }
        if (*outspec == '!') {
                error(USER, "command output not supported by RcontribSimulManager");
                return false;
        }
        if (!nChan) {                           // initial call?
                if ((xres < 0) | (yres <= 0)) {
                        error(USER, "xres, yres must be set before first modifier");
                        return false;
                }
                if (!SetDataFormat(dtyp))
                        return false;
                nChan = NCSAMP;
        } else if (nChan != NCSAMP) {
                error(USER, "# spectral channels must be fixed in AddModifier()");
                return false;
        }
        if (Ready()) {
                error(INTERNAL, "call to AddModifier() after PrepOutput()");
                return false;
        }
        LUENT *         lp = lu_find(&modLUT, modn);
        if (lp->data) {
                sprintf(errmsg, "duplicate modifier '%s'", modn);
                error(USER, errmsg);
                return false;
        }
        if (!lp->key)                   // create new entry
                lp->key = strcpy((char *)emalloc(strlen(modn)+1), modn);

        RcontribMod *   mp = NewRcMod(prms, binval, bincnt);
        if (!mp) return false;
        lp->data = (char *)mp;
        const int       modndx = hasFormat(outspec, "sb");
        const int       binndx = hasFormat(outspec, "diouxX");
        int             bin0 = 0;
        char            fnbuf[512];
        if (!modndx || (binndx > 0) & (modndx > binndx))
                sprintf(fnbuf, outspec, bin0, modn);
        else
                sprintf(fnbuf, outspec, modn, bin0);
        RcontribOutput *        olast = NULL;
        RcontribOutput *        op;
        for (op = outList; op; op = (olast=op)->next) {
                if (strcmp(op->GetName(), fnbuf))
                        continue;
                if (modndx) {           // this ain't right
                        sprintf(errmsg, "output name collision for '%s'", fnbuf);
                        error(USER, errmsg);
                        return false;
                }
                if ((binndx > 0) & (xres > 0)) {
                        sprintf(fnbuf, outspec, ++bin0);
                        continue;       // each bin goes to another image
                }
                mp->coffset = op->rowBytes;     // else add to what's there
                break;
        }
        if (!op) {                      // create new output channel?
                op = new RcontribOutput(fnbuf);
                if (olast) olast->next = op;
                else outList = op;
        }
        mp->opl = op;                   // first (maybe only) output channel
        if (modndx)                     // remember modifier if part of name
                op->omod = lp->key;
        if (binndx) {                   // append output image/bin list
                op->rowBytes += dsiz;
                op->obin = bin0;
                for (bincnt = 1; bincnt < mp->nbins; bincnt++) {
                        if (!modndx || (binndx > 0) &  (modndx > binndx))
                                sprintf(fnbuf, outspec, bin0+bincnt, modn);
                        else
                                sprintf(fnbuf, outspec, modn, bin0+bincnt);
                        if (!op->next) {
                                olast = op;
                                olast->next = op = new RcontribOutput(fnbuf);
                                if (modndx) op->omod = lp->key;
                                op->obin = bin0+bincnt;
                        } else {
                                op = op->next;
                                CHECK(op->obin != bin0+bincnt, CONSISTENCY,
                                        "bin number mismatch in AddModifier()");
                        }
                        CHECK(op->rowBytes != mp->coffset, CONSISTENCY,
                                        "row offset mismatch in AddModifier()");
                        op->rowBytes += dsiz;
                }
        } else                          // else send all results to this channel
                op->rowBytes += mp->nbins*dsiz;
        return true;
}

// Add a file of modifiers with associated arguments
bool
RcontribSimulManager::AddModFile(const char *modfn, const char *outspec,
                                                const char *prms,
                                                const char *binval, int bincnt)
{
        char *          path = getpath(const_cast<char *>(modfn),
                                        getrlibpath(), R_OK);
        FILE *          fp;
        if (!path || !(fp = fopen(path, "r"))) {
                sprintf(errmsg, "cannot %s modifier file '%s'",
                                path ? "open" : "find", modfn);
                error(SYSTEM, errmsg);
                return false;
        }
        char            mod[MAXSTR];
        while (fgetword(mod, sizeof(mod), fp))
                if (!AddModifier(mod, outspec, prms, binval, bincnt)) {
                        fclose(fp);
                        return false;
                }
        fclose(fp);
        return true;
}

// call-back to check if modifier has been loaded
static int
checkModExists(const LUENT *lp, void *p)
{
        OBJECT  mod = modifier(lp->key);

        if ((mod != OVOID) & (mod < nsceneobjs))
                return 1;

        sprintf(errmsg, "tracked modifier '%s' not found in main scene", lp->key);
        error(WARNING, errmsg);
        return 0;
}

// Prepare output channels and return # completed rows
int
RcontribSimulManager::PrepOutput()
{
        if (!outList || !RtraceSimulManager::Ready()) {
                error(INTERNAL, "PrepOutput() called before octree & modifiers set");
                return -1;
        }
        if (!cdsF) {
                error(INTERNAL, "missing RdataShare constructor call (cdsF)");
                return -1;
        }
        if (lu_doall(&modLUT, checkModExists, NULL) < 0)
                return -1;

        outList->nRows = yres * (xres + !xres); // all outputs have same #rows
        int     remWarnings = 20;
        for (RcontribOutput *op = outList; op; op = op->next) {
                if (op->rData) {
                        error(INTERNAL, "output channel already open in PrepOutput()");
                        return -1;
                }
                op->nRows = outList->nRows;
                op->rData = (*cdsF)(op->ofname, outOp,
                                        GetHeadLen()+1024 + op->nRows*op->rowBytes);
                freeqstr(op->ofname); op->ofname = NULL;
                if (outOp == RCOrecover) {
                        int     rd = op->CheckHeader(this);
                        if (rd < 0)
                                return -1;
                        if (rd >= op->nRows) {
                                if (remWarnings > 0) {
                                        sprintf(errmsg, "recovered output '%s' is complete",
                                                        op->GetName());
                                        error(WARNING, --remWarnings ? errmsg : "etc...");
                                }
                                rd = op->nRows;
                        }
                        if (!rInPos | (rInPos > rd)) rInPos = rd;
                } else if (!op->NewHeader(this))
                        return -1;
                                                // make sure there's room
                if (op->rData->GetSize() < op->begData + op->nRows*op->rowBytes &&
                                !op->rData->Resize(op->begData + op->nRows*op->rowBytes))
                        return -1;              // calls error() for us
        }
        rowsDone.NewBitMap(outList->nRows);     // create row completion map
        rowsDone.ClearBits(0, rInPos, true);
        return nrDone = rInPos;
}

// Create header in open write-only channel
bool
RcontribOutput::NewHeader(const RcontribSimulManager *rcp)
{
        int                     headlim = rcp->GetHeadLen() + 1024;
        char *                  hdr = (char *)rData->GetMemory(0, headlim, 0);
        int                     esiz;
        const int               etyp = rcp->GetFormat(&esiz);

        strcpy(hdr, HDRSTR);
        strcat(hdr, "RADIANCE\n");
        begData = strlen(hdr);
        strcpy(hdr+begData, rcp->GetHeadStr());
        begData += rcp->GetHeadLen();
        if (omod) {
                sprintf(hdr+begData, "MODIFIER=%s\n", omod);
                begData += strlen(hdr+begData);
        }
        if (obin >= 0) {
                sprintf(hdr+begData, "BIN=%d\n", obin);
                begData += strlen(hdr+begData);
        }
        strcpy(hdr+begData, ROWZEROSTR);
        rowCountPos = begData+LNROWSTR;
        begData += sizeof(ROWZEROSTR)-1;
        if (!rcp->xres | (rowBytes > esiz)) {
                sprintf(hdr+begData, "NCOLS=%d\n", int(rowBytes/esiz));
                begData += strlen(hdr+begData);
        }
        sprintf(hdr+begData, "%s%d\n", NCOMPSTR, NCSAMP);
        begData += strlen(hdr+begData);
        if (NCSAMP > 3) {
                sprintf(hdr+begData, "%s %g %g %g %g\n", WLSPLTSTR,
                                WLPART[0], WLPART[1], WLPART[2], WLPART[3]);
                begData += strlen(hdr+begData);
        }
        if (etyp != 'c') {
                sprintf(hdr+begData, "%s%d\n", BIGEND, nativebigendian());
                begData += strlen(hdr+begData);
        }
        int     align = 0;
        switch (etyp) {
        case 'f':
                align = sizeof(float);
                break;
        case 'd':
                align = sizeof(double);
                break;
        case 'c':
                break;
        default:
                error(INTERNAL, "unsupported data type in NewHeader()");
                return false;
        }
        strcpy(hdr+begData, FMTSTR);    // write format string
        begData += strlen(hdr+begData);
        strcpy(hdr+begData, formstr(etyp));
        begData += strlen(hdr+begData);
        if (align)                      // align data at end of header
                while ((begData+2) % align)
                        hdr[begData++] = ' ';
        hdr[begData++] = '\n';          // EOL for data format
        hdr[begData++] = '\n';          // end of nominal header
        if ((rcp->xres > 0) & (rowBytes == esiz)) {     // tack on resolution string?
                sprintf(hdr+begData, PIXSTDFMT, rcp->yres, rcp->xres);
                begData += strlen(hdr+begData);
        }
        return rData->ReleaseMemory(hdr, RDSwrite);
}

// find string argument in header for named variable
static const char *
findArgs(const char *hdr, const char *vnm, int len)
{
        const char *    npos = strnstr(hdr, vnm, len);

        if (!npos) return NULL;

        npos += strlen(vnm);            // find start of (first) argument
        len -= npos - hdr;
        while (len-- > 0 && (*npos == '=') | isspace(*npos))
                if (*npos++ == '\n')
                        return NULL;

        return (len >= 0) ? npos : NULL;
}

// Load and check header in read/write channel
int
RcontribOutput::CheckHeader(const RcontribSimulManager *rcp)
{
        int             esiz;
        const int       etyp = rcp->GetFormat(&esiz);
        const int       maxlen = rcp->GetHeadLen() + 1024;
        char *          hdr = (char *)rData->GetMemory(0, maxlen, RDSread);
        const char *    cp;
                                                // find end of header
        if (!hdr || !(cp = strnstr(hdr, "\n\n", maxlen))) {
                sprintf(errmsg, "cannot find end of header in '%s'", GetName());
                error(USER, errmsg);
                return -1;
        }
        begData = cp - hdr + 1;                 // increment again at end
                                                // check # components
        if (((cp = findArgs(hdr, NCOMPSTR, begData)) ? atoi(cp) : 3) != NCSAMP) {
                sprintf(errmsg, "expected %s%d in '%s'", NCOMPSTR, NCSAMP, GetName());
                error(USER, errmsg);
                return -1;
        }
                                                // check format
        if (!(cp = findArgs(hdr, FMTSTR, begData)) ||
                                strncmp(cp, formstr(etyp), strlen(formstr(etyp)))) {
                sprintf(errmsg, "expected %s%s in '%s'", FMTSTR, formstr(etyp), GetName());
                error(USER, errmsg);
                return -1;
        }
                                                // check #columns
        if ((cp = findArgs(hdr, "NCOLS=", begData)) ? (atoi(cp)*esiz != rowBytes)
                                                    : (!rcp->xres | (rowBytes > esiz))) {
                sprintf(errmsg, "expected NCOLS=%d in '%s'", int(rowBytes/esiz), GetName());
                error(USER, errmsg);
                return -1;
        }
                                                // find row count
        if (!(cp = findArgs(hdr, "NROWS=", begData))) {
                sprintf(errmsg, "missing NROWS in '%s'", GetName());
                error(USER, errmsg);
                return -1;
        }
        rowCountPos = cp - hdr;
        int     rlast = atoi(cp);
        begData++;                              // advance past closing EOL
        if ((rcp->xres > 0) & (rowBytes == esiz)) {     // check/skip resolution string?
                char    rbuf[64];
                sprintf(rbuf, PIXSTDFMT, rcp->yres, rcp->xres);
                int     rlen = strlen(rbuf);
                if (strncmp(rbuf, hdr+begData, rlen)) {
                        sprintf(errmsg, "bad resolution string in '%s'", GetName());
                        error(USER, errmsg);
                        return -1;
                }
                begData += rlen;
        }
        // XXX assume the rest is OK: endianness, wavelength splits, modifier, bin
        return rData->ReleaseMemory(hdr, 0) ? rlast : -1;
}

// Rewind calculation (previous results unchanged)
bool
RcontribSimulManager::ResetRow(int r)
{
        if (!rowsDone.Length() | (0 > r) | (r >= rInPos)) {
                error(WARNING, "ignoring bad call to ResetRow()");
                return (r == rInPos);
        }
        FlushQueue();                   // finish current and reset
        for (RcontribOutput *op = outList; op; op = op->next)
                if (!op->SetRowsDone(r))
                        return false;

        rowsDone.ClearBits(r, rInPos-r, false);
        nrDone = rInPos = r;
        return true;
}

// call-back for averaging each modifier's contributions to assigned channel(s)
static int
putModContrib(const LUENT *lp, void *p)
{
        RcontribMod *                   mp = (RcontribMod *)lp->data;
        const RcontribSimulManager *    rcp = (const RcontribSimulManager *)p;
        const double                    sca = 1./rcp->accum;
        const DCOLORV *                 dvp = mp->cbin;
        RcontribOutput *                op = mp->opl;
        int                             i, n;

        switch (rcp->GetFormat()) {     // conversion based on output type
        case 'd': {
                double *        dvo = (double *)op->InsertionP(mp->coffset);
                for (n = mp->nbins; n--; ) {
                        for (i = 0; i < NCSAMP; i++)
                                *dvo++ = *dvp++ * sca;
                        if ((op->obin >= 0) & (n > 0))
                                dvo = (double *)(op = op->Next())->InsertionP(mp->coffset);
                }
                } break;
        case 'f': {
                float *         fvo = (float *)op->InsertionP(mp->coffset);
                for (n = mp->nbins; n--; ) {
                        for (i = 0; i < NCSAMP; i++)
                                *fvo++ = float(*dvp++ * sca);
                        if ((op->obin >= 0) & (n > 0))
                                fvo = (float *)(op = op->Next())->InsertionP(mp->coffset);
                }
                } break;
        case 'c': {
                COLRV *         cvo = (COLRV *)op->InsertionP(mp->coffset);
                for (n = mp->nbins; n--; ) {
                        SCOLOR  scol;
                        for (i = 0; i < NCSAMP; i++)
                                scol[i] = COLORV(*dvp++ * sca);
                        scolor_scolr(cvo, scol);
                        cvo += LSCOLR;
                        if ((op->obin >= 0) & (n > 0))
                                cvo = (COLRV *)(op = op->Next())->InsertionP(mp->coffset);
                }
                } break;
        default:
                error(CONSISTENCY, "unsupported output type in putModContrib()");
                return -1;
        }
                                                // clear for next tally
        memset(mp->cbin, 0, sizeof(DCOLORV)*NCSAMP*mp->nbins);
        return 1;
}

// Add a ray/bundle to compute next record
int
RcontribSimulManager::ComputeRecord(const FVECT orig_direc[])
{
        if (!Ready())
                return 0;
        if (rInPos >= outList->nRows) {
                error(WARNING, "ComputeRecord() called after last record");
                return 0;
        }
        if (nkids > 0) {                        // in parent process?
                int     k = GetChild(false);    // updates output rows
                if (k < 0) return -1;           // someone died?
                RowAssignment   rass;
                rass.row = kidRow[k] = rInPos++;
                rass.ac = accum;
                if (write(kid[k].w, &rass, sizeof(rass)) != sizeof(rass) ||
                                writebuf(kid[k].w, orig_direc, sizeof(FVECT)*2*accum)
                                                != sizeof(FVECT)*2*accum) {
                        error(SYSTEM, "cannot write to child; dead process?");
                        return -1;
                }
                return accum;                   // tracing/output happens in child
        }
        if (NCSAMP != nChan) {
                error(INTERNAL, "number of color channels must remain fixed");
                return -1;
        }
                                                // actual work is done here...
        if (EnqueueBundle(orig_direc, accum) < 0)
                return -1;

        RcontribOutput *        op;             // prepare output buffers
        for (op = outList; op; op = op->next)
                if (!op->GetRow(rInPos))
                        return -1;
                                                // convert averages & clear
        if (lu_doall(&modLUT, putModContrib, this) < 0)
                return -1;
                                                // write buffers
        for (op = outList; op; op = op->next)
                op->DoneRow();

        if (!nkids)                             // update row if solo process
                UpdateRowsDone(rInPos++);       // XXX increment here is critical

        return accum;
}

// Get next available child, returning index or -1 if forceWait & idling
int
RcontribSimulManager::GetChild(bool forceWait)
{
        if (nkids <= 0)
                return -1;
                                                // take inventory
        int     pn, n = 0;
        fd_set  readset, errset;
        FD_ZERO(&readset); FD_ZERO(&errset);
        for (pn = nkids; pn--; ) {
                if (kidRow[pn] < 0) {           // child already ready?
                        if (forceWait) continue;
                        return pn;              // good enough
                }
                FD_SET(kid[pn].r, &readset);    // will check on this one
                FD_SET(kid[pn].r, &errset);
                if (kid[pn].r >= n)
                        n = kid[pn].r + 1;
        }
        if (!n)                                 // every child is idle?
                return -1;
                                                // wait on "busy" child(ren)
        while ((n = select(n, &readset, NULL, &errset, NULL)) <= 0)
                if (errno != EINTR) {
                        error(SYSTEM, "select call failed in GetChild()");
                        return -1;
                }
        char    buf[sizeof(ROW_DONE)] = "X";
        pn = -1;                                // get flags set by select
        for (n = nkids; n--; )
                if (kidRow[n] >= 0 &&
                                FD_ISSET(kid[n].r, &readset) |
                                FD_ISSET(kid[n].r, &errset)) {
                                                // check for error
                        if (FD_ISSET(kid[n].r, &errset) ||
                                        read(kid[n].r, buf, sizeof(ROW_DONE)) <= 0 ||
                                        memcmp(buf, ROW_DONE, sizeof(ROW_DONE)))
                                return -1;
                                                // update output row counts
                        UpdateRowsDone(kidRow[n]);
                        kidRow[n] = -1;         // flag child available
                        pn = n;
                }
        return pn;
}

// Update row completion bitmap and update outputs (does not change rInPos)
bool
RcontribSimulManager::UpdateRowsDone(int r)
{
        if (!rowsDone.TestAndSet(r)) {
                error(WARNING, "redundant call to UpdateRowsDone()");
                return false;
        }
        GetRowFinished();
        if (nrDone <= r)
                return true;                    // nothing to update, yet
        for (RcontribOutput *op = outList; op; op = op->next)
                if (!op->SetRowsDone(nrDone))
                        return false;
        return true;                            // up-to-date
}

// Run rcontrib child process (never returns)
void
RcontribSimulManager::RunChild()
{
        FVECT *         vecList = NULL;
        RowAssignment   rass;
        ssize_t         nr;

        accum = 0;
        errno = 0;
        while ((nr = read(0, &rass, sizeof(rass))) == sizeof(rass)) {
                if (!rass.ac) {
                        error(CONSISTENCY, "bad accumulator count in child");
                        exit(1);
                }
                if (rass.ac > accum) {
                        efree(vecList);
                        vecList = (FVECT *)emalloc(sizeof(FVECT)*2*rass.ac);
                }
                accum = rass.ac;
                rInPos = rass.row;

                if (readbuf(0, vecList, sizeof(FVECT)*2*accum) !=
                                        sizeof(FVECT)*2*accum)
                        break;

                if (ComputeRecord(vecList) <= 0)
                        exit(1);
                                                // signal this row is done
                if (write(1, ROW_DONE, sizeof(ROW_DONE)) != sizeof(ROW_DONE))
                        exit(1);
        }
        if (nr) {
                error(SYSTEM, "read error in child process");
                exit(1);
        }
        exit(0);
}

// Add child processes as indicated
bool
RcontribSimulManager::StartKids(int n2go)
{
        if ((n2go <= 0) | (nkids + n2go <= 1))
                return false;

        if (!nkids)
                cow_memshare();                 // preload objects

        n2go += nkids;          // => desired brood size
        kid = (SUBPROC *)erealloc(kid, sizeof(SUBPROC)*n2go);
        kidRow = (int32 *)erealloc(kidRow, sizeof(int32)*n2go);

        fflush(stdout);                         // shouldn't use, anyway
        while (nkids < n2go) {
                kid[nkids] = sp_inactive;
                int     rv = open_process(&kid[nkids], NULL);
                if (!rv) {                      // in child process?
                        while (nkids-- > 0) {
                                close(kid[nkids].r);
                                close(kid[nkids].w);
                        }
                        free(kid); free(kidRow);
                        kid = NULL; kidRow = NULL;
                        RunChild();             // should never return
                        _exit(1);
                }
                if (rv < 0) {
                        error(SYSTEM, "cannot fork worker process");
                        return false;
                }
                kidRow[nkids++] = -1;           // newborn is ready
        }
        return true;
}

// Reap the indicated number of children (all if 0)
int
RcontribSimulManager::StopKids(int n2end)
{
        if (nkids <= 0)
                return 0;
        FlushQueue();
        int     status = 0;
        if (!n2end | (n2end >= nkids)) {        // end all subprocesses?
                status = close_processes(kid, nkids);
                free(kid); free(kidRow);
                kid = NULL; kidRow = NULL;
                nkids = 0;
        } else {                                // else shrink family
                int     st;
                while (n2end-- > 0)
                        if ((st = close_process(&kid[--nkids])) > 0)
                                status = st;
                // could call realloc(), but it hardly matters
        }
        if (status) {
                sprintf(errmsg, "non-zero (%d) status from child", status);
                error(WARNING, errmsg);
        }
        return status;
}

// Set number of computation threads (0 => #cores)
int
RcontribSimulManager::SetThreadCount(int nt)
{
        if (!Ready()) {
                error(INTERNAL, "must call PrepOutput() before SetThreadCount()");
                return 0;
        }
        if (nt < 0)
                return NThreads();
        if (!nt) nt = GetNCores();
        int     status = 0;
        if (nt == 1)
                status = StopKids();
        else if (nt < nkids)
                status = StopKids(nkids-nt);
        else if (nt > nkids)
                StartKids(nt-nkids);
        if (status) {
                sprintf(errmsg, "non-zero (%d) status from child", status);
                error(WARNING, errmsg);
        }
        return NThreads();
}
Revision:	2.24
Committed:	Wed Nov 12 19:41:21 2025 UTC (30 hours, 24 minutes ago) by greg
Branch:	MAIN
CVS Tags:	HEAD
Changes since 2.23:	+9 -8 lines
Log Message:	perf(rtcontrib,rxfluxmtx): Minor optimization