| 1 | /* |
| 2 | * Copyright (c) 1987 by Ed James, UC Berkeley. All rights reserved. |
| 3 | * |
| 4 | * Copy permission is hereby granted provided that this notice is |
| 5 | * retained on all partial or complete copies. |
| 6 | * |
| 7 | * For more info on this and all of my stuff, mail edjames@berkeley.edu. |
| 8 | */ |
| 9 | |
| 10 | #ifndef lint |
| 11 | static char sccsid[] = "@(#)update.c 5.3 (Berkeley) %G%"; |
| 12 | #endif not lint |
| 13 | |
| 14 | #include "include.h" |
| 15 | |
| 16 | update() |
| 17 | { |
| 18 | int i, dir_diff, mask, unclean; |
| 19 | PLANE *pp, *p1, *p2, *p; |
| 20 | |
| 21 | #ifdef BSD |
| 22 | mask = sigblock(sigmask(SIGINT)); |
| 23 | #endif |
| 24 | #ifdef SYSV |
| 25 | alarm(0); |
| 26 | signal(SIGALRM, update); |
| 27 | #endif |
| 28 | |
| 29 | clock++; |
| 30 | |
| 31 | erase_all(); |
| 32 | |
| 33 | /* put some planes in the air */ |
| 34 | do { |
| 35 | unclean = 0; |
| 36 | for (pp = ground.head; pp != NULL; pp = pp->next) { |
| 37 | if (pp->new_altitude > 0) { |
| 38 | delete(&ground, pp); |
| 39 | append(&air, pp); |
| 40 | unclean = 1; |
| 41 | break; |
| 42 | } |
| 43 | } |
| 44 | } while (unclean); |
| 45 | |
| 46 | /* do altitude change and basic movement */ |
| 47 | for (pp = air.head; pp != NULL; pp = pp->next) { |
| 48 | /* type 0 only move every other turn */ |
| 49 | if (pp->plane_type == 0 && clock & 1) |
| 50 | continue; |
| 51 | |
| 52 | pp->fuel--; |
| 53 | if (pp->fuel < 0) |
| 54 | loser(pp, "ran out of fuel."); |
| 55 | |
| 56 | pp->altitude += SGN(pp->new_altitude - pp->altitude); |
| 57 | |
| 58 | if (!pp->delayd) { |
| 59 | dir_diff = pp->new_dir - pp->dir; |
| 60 | /* |
| 61 | * Allow for circle commands |
| 62 | */ |
| 63 | if (pp->new_dir >= 0 && pp->new_dir < MAXDIR) { |
| 64 | if (dir_diff > MAXDIR/2) |
| 65 | dir_diff -= MAXDIR; |
| 66 | else if (dir_diff < -(MAXDIR/2)) |
| 67 | dir_diff += MAXDIR; |
| 68 | } |
| 69 | if (dir_diff > 2) |
| 70 | dir_diff = 2; |
| 71 | else if (dir_diff < -2) |
| 72 | dir_diff = -2; |
| 73 | pp->dir += dir_diff; |
| 74 | if (pp->dir >= MAXDIR) |
| 75 | pp->dir -= MAXDIR; |
| 76 | else if (pp->dir < 0) |
| 77 | pp->dir += MAXDIR; |
| 78 | } |
| 79 | pp->xpos += displacement[pp->dir].dx; |
| 80 | pp->ypos += displacement[pp->dir].dy; |
| 81 | |
| 82 | if (pp->delayd && pp->xpos == sp->beacon[pp->delayd_no].x && |
| 83 | pp->ypos == sp->beacon[pp->delayd_no].y) { |
| 84 | pp->delayd = 0; |
| 85 | if (pp->status == S_UNMARKED) |
| 86 | pp->status = S_MARKED; |
| 87 | } |
| 88 | |
| 89 | switch (pp->dest_type) { |
| 90 | case T_AIRPORT: |
| 91 | if (pp->xpos == sp->airport[pp->dest_no].x && |
| 92 | pp->ypos == sp->airport[pp->dest_no].y && |
| 93 | pp->altitude == 0) { |
| 94 | if (pp->dir != sp->airport[pp->dest_no].dir) |
| 95 | loser(pp, "landed in the wrong direction."); |
| 96 | else { |
| 97 | pp->status = S_GONE; |
| 98 | continue; |
| 99 | } |
| 100 | } |
| 101 | break; |
| 102 | case T_EXIT: |
| 103 | if (pp->xpos == sp->exit[pp->dest_no].x && |
| 104 | pp->ypos == sp->exit[pp->dest_no].y) { |
| 105 | if (pp->altitude != 9) |
| 106 | loser(pp, "exited at the wrong altitude."); |
| 107 | else { |
| 108 | pp->status = S_GONE; |
| 109 | continue; |
| 110 | } |
| 111 | } |
| 112 | break; |
| 113 | default: |
| 114 | loser(pp, "has a bizarre destination, get help!"); |
| 115 | } |
| 116 | if (pp->altitude > 9) |
| 117 | /* "this is impossible" */ |
| 118 | loser(pp, "exceded flight ceiling."); |
| 119 | if (pp->altitude <= 0) { |
| 120 | for (i = 0; i < sp->num_airports; i++) |
| 121 | if (pp->xpos == sp->airport[i].x && |
| 122 | pp->ypos == sp->airport[i].y) { |
| 123 | if (pp->dest_type == T_AIRPORT) |
| 124 | loser(pp, |
| 125 | "landed at the wrong airport."); |
| 126 | else |
| 127 | loser(pp, |
| 128 | "landed instead of exited."); |
| 129 | } |
| 130 | loser(pp, "crashed on the ground."); |
| 131 | } |
| 132 | if (pp->xpos < 1 || pp->xpos >= sp->width - 1 || |
| 133 | pp->ypos < 1 || pp->ypos >= sp->height - 1) { |
| 134 | for (i = 0; i < sp->num_exits; i++) |
| 135 | if (pp->xpos == sp->exit[i].x && |
| 136 | pp->ypos == sp->exit[i].y) { |
| 137 | if (pp->dest_type == T_EXIT) |
| 138 | loser(pp, |
| 139 | "exited via the wrong exit."); |
| 140 | else |
| 141 | loser(pp, |
| 142 | "exited instead of landed."); |
| 143 | } |
| 144 | loser(pp, "illegally left the flight arena."); |
| 145 | } |
| 146 | } |
| 147 | |
| 148 | /* |
| 149 | * Traverse the list once, deleting the planes that are gone. |
| 150 | */ |
| 151 | for (pp = air.head; pp != NULL; pp = p2) { |
| 152 | p2 = pp->next; |
| 153 | if (pp->status == S_GONE) { |
| 154 | safe_planes++; |
| 155 | delete(&air, pp); |
| 156 | } |
| 157 | } |
| 158 | |
| 159 | draw_all(); |
| 160 | |
| 161 | for (p1 = air.head; p1 != NULL; p1 = p1->next) |
| 162 | for (p2 = p1->next; p2 != NULL; p2 = p2->next) |
| 163 | if (too_close(p1, p2, 1)) { |
| 164 | static char buf[80]; |
| 165 | |
| 166 | (void)sprintf(buf, "collided with plane '%c'.", |
| 167 | name(p2)); |
| 168 | loser(p1, buf); |
| 169 | } |
| 170 | /* |
| 171 | * Check every other update. Actually, only add on even updates. |
| 172 | * Otherwise, prop jobs show up *on* entrance. Remember that |
| 173 | * we don't update props on odd updates. |
| 174 | */ |
| 175 | if ((rand() % sp->newplane_time) == 0) |
| 176 | addplane(); |
| 177 | |
| 178 | #ifdef BSD |
| 179 | sigsetmask(mask); |
| 180 | #endif |
| 181 | #ifdef SYSV |
| 182 | alarm(sp->update_secs); |
| 183 | #endif |
| 184 | } |
| 185 | |
| 186 | char * |
| 187 | command(pp) |
| 188 | PLANE *pp; |
| 189 | { |
| 190 | static char buf[50], *bp, *comm_start; |
| 191 | char *index(); |
| 192 | |
| 193 | buf[0] = '\0'; |
| 194 | bp = buf; |
| 195 | (void)sprintf(bp, "%c%d%c%c%d: ", name(pp), pp->altitude, |
| 196 | (pp->fuel < LOWFUEL) ? '*' : ' ', |
| 197 | (pp->dest_type == T_AIRPORT) ? 'A' : 'E', pp->dest_no); |
| 198 | |
| 199 | comm_start = bp = index(buf, '\0'); |
| 200 | if (pp->altitude == 0) |
| 201 | (void)sprintf(bp, "Holding @ A%d", pp->orig_no); |
| 202 | else if (pp->new_dir >= MAXDIR || pp->new_dir < 0) |
| 203 | strcpy(bp, "Circle"); |
| 204 | else if (pp->new_dir != pp->dir) |
| 205 | (void)sprintf(bp, "%d", dir_deg(pp->new_dir)); |
| 206 | |
| 207 | bp = index(buf, '\0'); |
| 208 | if (pp->delayd) |
| 209 | (void)sprintf(bp, " @ B%d", pp->delayd_no); |
| 210 | |
| 211 | bp = index(buf, '\0'); |
| 212 | if (*comm_start == '\0' && |
| 213 | (pp->status == S_UNMARKED || pp->status == S_IGNORED)) |
| 214 | strcpy(bp, "---------"); |
| 215 | return (buf); |
| 216 | } |
| 217 | |
| 218 | /* char */ |
| 219 | name(p) |
| 220 | PLANE *p; |
| 221 | { |
| 222 | if (p->plane_type == 0) |
| 223 | return ('A' + p->plane_no); |
| 224 | else |
| 225 | return ('a' + p->plane_no); |
| 226 | } |
| 227 | |
| 228 | number(l) |
| 229 | { |
| 230 | if (l < 'a' && l > 'z' && l < 'A' && l > 'Z') |
| 231 | return (-1); |
| 232 | else if (l >= 'a' && l <= 'z') |
| 233 | return (l - 'a'); |
| 234 | else |
| 235 | return (l - 'A'); |
| 236 | } |
| 237 | |
| 238 | next_plane() |
| 239 | { |
| 240 | static int last_plane = -1; |
| 241 | PLANE *pp; |
| 242 | int found, start_plane = last_plane; |
| 243 | |
| 244 | do { |
| 245 | found = 0; |
| 246 | last_plane++; |
| 247 | if (last_plane >= 26) |
| 248 | last_plane = 0; |
| 249 | for (pp = air.head; pp != NULL; pp = pp->next) |
| 250 | if (pp->plane_no == last_plane) { |
| 251 | found++; |
| 252 | break; |
| 253 | } |
| 254 | if (!found) |
| 255 | for (pp = ground.head; pp != NULL; pp = pp->next) |
| 256 | if (pp->plane_no == last_plane) { |
| 257 | found++; |
| 258 | break; |
| 259 | } |
| 260 | } while (found && last_plane != start_plane); |
| 261 | if (last_plane == start_plane) |
| 262 | return (-1); |
| 263 | return (last_plane); |
| 264 | } |
| 265 | |
| 266 | addplane() |
| 267 | { |
| 268 | PLANE p, *pp, *p1; |
| 269 | int i, num_starts, close, rnd, rnd2, pnum; |
| 270 | |
| 271 | bzero(&p, sizeof (p)); |
| 272 | |
| 273 | p.status = S_MARKED; |
| 274 | p.plane_type = random() % 2; |
| 275 | |
| 276 | num_starts = sp->num_exits + sp->num_airports; |
| 277 | rnd = random() % num_starts; |
| 278 | |
| 279 | if (rnd < sp->num_exits) { |
| 280 | p.dest_type = T_EXIT; |
| 281 | p.dest_no = rnd; |
| 282 | } else { |
| 283 | p.dest_type = T_AIRPORT; |
| 284 | p.dest_no = rnd - sp->num_exits; |
| 285 | } |
| 286 | |
| 287 | /* loop until we get a plane not near another */ |
| 288 | for (i = 0; i < num_starts; i++) { |
| 289 | /* loop till we get a different start point */ |
| 290 | while ((rnd2 = random() % num_starts) == rnd) |
| 291 | ; |
| 292 | if (rnd2 < sp->num_exits) { |
| 293 | p.orig_type = T_EXIT; |
| 294 | p.orig_no = rnd2; |
| 295 | p.xpos = sp->exit[rnd2].x; |
| 296 | p.ypos = sp->exit[rnd2].y; |
| 297 | p.new_dir = p.dir = sp->exit[rnd2].dir; |
| 298 | p.altitude = p.new_altitude = 7; |
| 299 | close = 0; |
| 300 | for (p1 = air.head; p1 != NULL; p1 = p1->next) |
| 301 | if (too_close(p1, &p, 4)) { |
| 302 | close++; |
| 303 | break; |
| 304 | } |
| 305 | if (close) |
| 306 | continue; |
| 307 | } else { |
| 308 | p.orig_type = T_AIRPORT; |
| 309 | p.orig_no = rnd2 - sp->num_exits; |
| 310 | p.xpos = sp->airport[p.orig_no].x; |
| 311 | p.ypos = sp->airport[p.orig_no].y; |
| 312 | p.new_dir = p.dir = sp->airport[p.orig_no].dir; |
| 313 | p.altitude = p.new_altitude = 0; |
| 314 | } |
| 315 | p.fuel = sp->width + sp->height; |
| 316 | break; |
| 317 | } |
| 318 | if (i >= num_starts) |
| 319 | return (-1); |
| 320 | pnum = next_plane(); |
| 321 | if (pnum < 0) |
| 322 | return (-1); |
| 323 | p.plane_no = pnum; |
| 324 | |
| 325 | pp = newplane(); |
| 326 | bcopy(&p, pp, sizeof (p)); |
| 327 | |
| 328 | if (pp->orig_type == T_AIRPORT) |
| 329 | append(&ground, pp); |
| 330 | else |
| 331 | append(&air, pp); |
| 332 | |
| 333 | return (pp->dest_type); |
| 334 | } |
| 335 | |
| 336 | PLANE * |
| 337 | findplane(n) |
| 338 | { |
| 339 | PLANE *pp; |
| 340 | |
| 341 | for (pp = air.head; pp != NULL; pp = pp->next) |
| 342 | if (pp->plane_no == n) |
| 343 | return (pp); |
| 344 | for (pp = ground.head; pp != NULL; pp = pp->next) |
| 345 | if (pp->plane_no == n) |
| 346 | return (pp); |
| 347 | return (NULL); |
| 348 | } |
| 349 | |
| 350 | too_close(p1, p2, dist) |
| 351 | PLANE *p1, *p2; |
| 352 | { |
| 353 | if (ABS(p1->altitude - p2->altitude) <= dist && |
| 354 | ABS(p1->xpos - p2->xpos) <= dist && ABS(p1->ypos - p2->ypos) <= dist) |
| 355 | return (1); |
| 356 | else |
| 357 | return (0); |
| 358 | } |
| 359 | |
| 360 | dir_deg(d) |
| 361 | { |
| 362 | switch (d) { |
| 363 | case 0: return (0); |
| 364 | case 1: return (45); |
| 365 | case 2: return (90); |
| 366 | case 3: return (135); |
| 367 | case 4: return (180); |
| 368 | case 5: return (225); |
| 369 | case 6: return (270); |
| 370 | case 7: return (315); |
| 371 | default: |
| 372 | return (-1); |
| 373 | } |
| 374 | } |