/* projection initialization and closure */ #ifndef lint static const char SCCSID[]="@(#)pj_init.c 4.13 95/09/05 GIE REL"; #endif #define PJ_LIB__ #include #include #include #include static paralist *start; extern FILE *pj_open_lib(char *, char *); static paralist * get_opt(FILE *fid, char *name, paralist *next) { char sword[52], *word = sword+1; int first = 1, len, c; len = strlen(name); *sword = 't'; while (fscanf(fid, "%50s", word) == 1) if (*word == '#') /* skip comments */ while((c = fgetc(fid)) != EOF && c != '\n') ; else if (*word == '<') { /* control name */ if (first && !strncmp(name, word + 1, len) && word[len + 1] == '>') first = 0; else if (!first && word[1] == '>') break; } else if (!first && !pj_param(start, sword).i) { /* don't default ellipse if datum is set */ if( strncmp(word,"ellps=",6) != 0 || !pj_param(start, "tdatum").i ) { next = next->next = pj_mkparam(word); } } if (errno == 25) errno = 0; return next; } static paralist * get_defaults(paralist *next, char *name) { FILE *fid; if (fid = pj_open_lib("proj_def.dat", "r")) { next = get_opt(fid, "general", next); rewind(fid); next = get_opt(fid, name, next); (void)fclose(fid); } if (errno) errno = 0; /* don't care if can't open file */ return next; } static paralist * get_init(paralist *next, char *name) { char fname[MAX_PATH_FILENAME+ID_TAG_MAX+3], *opt; FILE *fid; (void)strncpy(fname, name, MAX_PATH_FILENAME + ID_TAG_MAX + 1); if (opt = strrchr(fname, ':')) *opt++ = '\0'; else { pj_errno = -3; return(0); } if (fid = pj_open_lib(fname, "r")) next = get_opt(fid, opt, next); else return(0); (void)fclose(fid); if (errno == 25) errno = 0; /* unknown problem with some sys errno<-25 */ return next; } /************************************************************************/ /* pj_init() */ /* */ /* Main entry point for initialing a PJ projections */ /* definition. Note that the projection specific function is */ /* called to do the initial allocation so it can be created */ /* large enough to hold projection specific parameters. */ /************************************************************************/ PJ * pj_init(int argc, char **argv) { char *s, *name; void *(*proj)(PJ *); paralist *curr; int i; PJ *PIN = 0; errno = pj_errno = 0; /* put arguments into internal linked list */ if (argc <= 0) { pj_errno = -1; goto bum_call; } for (i = 0; i < argc; ++i) if (i) curr = curr->next = pj_mkparam(argv[i]); else start = curr = pj_mkparam(argv[i]); if (pj_errno) goto bum_call; /* check if +init present */ if (pj_param(start, "tinit").i) { paralist *last = curr; if (!(curr = get_init(curr, pj_param(start, "sinit").s))) goto bum_call; if (curr == last) { pj_errno = -2; goto bum_call; } } /* find projection selection */ if (!(name = pj_param(start, "sproj").s)) { pj_errno = -4; goto bum_call; } for (i = 0; (s = pj_list[i].id) && strcmp(name, s) ; ++i) ; if (!s) { pj_errno = -5; goto bum_call; } /* set defaults, unless inhibited */ if (!pj_param(start, "bno_defs").i) curr = get_defaults(curr, name); proj = pj_list[i].proj; /* allocate projection structure */ if (!(PIN = (*proj)(0))) goto bum_call; PIN->params = start; PIN->is_latlong = 0; /* set datum parameters */ if (pj_datum_set(start, PIN)) goto bum_call; /* set ellipsoid/sphere parameters */ if (pj_ell_set(start, &PIN->a, &PIN->es)) goto bum_call; PIN->e = sqrt(PIN->es); PIN->ra = 1. / PIN->a; PIN->one_es = 1. - PIN->es; if (PIN->one_es == 0.) { pj_errno = -6; goto bum_call; } PIN->rone_es = 1./PIN->one_es; /* Now that we have ellipse information check for WGS84 datum */ if( PIN->datum_type == PJD_3PARAM && PIN->datum_params[0] == 0.0 && PIN->datum_params[1] == 0.0 && PIN->datum_params[2] == 0.0 && PIN->a == 6378137.0 && ABS(PIN->es - 0.006694379990) < 0.000000000050 )/*WGS84/GRS80*/ { PIN->datum_type = PJD_WGS84; } /* set PIN->geoc coordinate system */ PIN->geoc = (PIN->es && pj_param(start, "bgeoc").i); /* over-ranging flag */ PIN->over = pj_param(start, "bover").i; /* central meridian */ PIN->lam0=pj_param(start, "rlon_0").f; /* central latitude */ PIN->phi0 = pj_param(start, "rlat_0").f; /* false easting and northing */ PIN->x0 = pj_param(start, "dx_0").f; PIN->y0 = pj_param(start, "dy_0").f; /* general scaling factor */ if (pj_param(start, "tk_0").i) PIN->k0 = pj_param(start, "dk_0").f; else if (pj_param(start, "tk").i) PIN->k0 = pj_param(start, "dk").f; else PIN->k0 = 1.; if (PIN->k0 <= 0.) { pj_errno = -31; goto bum_call; } /* set units */ s = 0; if (name = pj_param(start, "sunits").s) { for (i = 0; (s = pj_units[i].id) && strcmp(name, s) ; ++i) ; if (!s) { pj_errno = -7; goto bum_call; } s = pj_units[i].to_meter; } if (s || (s = pj_param(start, "sto_meter").s)) { PIN->to_meter = strtod(s, &s); if (*s == '/') /* ratio number */ PIN->to_meter /= strtod(++s, 0); PIN->fr_meter = 1. / PIN->to_meter; } else PIN->to_meter = PIN->fr_meter = 1.; /* projection specific initialization */ if (!(PIN = (*proj)(PIN)) || errno || pj_errno) { bum_call: /* cleanup error return */ if (!pj_errno) pj_errno = errno; if (PIN) pj_free(PIN); else for ( ; start; start = curr) { curr = start->next; pj_dalloc(start); } PIN = 0; } return PIN; } /************************************************************************/ /* pj_free() */ /* */ /* This is the application callable entry point for destroying */ /* a projection definition. It does work generic to all */ /* projection types, and then calls the projection specific */ /* free function (P->pfree()) to do local work. This maps to */ /* the FREEUP code in the individual projection source files. */ /************************************************************************/ void pj_free(PJ *P) { if (P) { paralist *t = P->params, *n; /* free parameter list elements */ for (t = P->params; t; t = n) { n = t->next; pj_dalloc(t); } /* free projection parameters */ P->pfree(P); } }