| 1 | # |
| 2 | /* |
| 3 | * UNIX shell |
| 4 | * |
| 5 | * S. R. Bourne |
| 6 | * Bell Telephone Laboratories |
| 7 | * |
| 8 | */ |
| 9 | |
| 10 | #include "defs.h" |
| 11 | |
| 12 | PROC BOOL chkid(); |
| 13 | |
| 14 | |
| 15 | NAMNOD ps2nod = { NIL, NIL, ps2name}, |
| 16 | fngnod = { NIL, NIL, fngname}, |
| 17 | pathnod = { NIL, NIL, pathname}, |
| 18 | ifsnod = { NIL, NIL, ifsname}, |
| 19 | ps1nod = { &pathnod, &ps2nod, ps1name}, |
| 20 | homenod = { &fngnod, &ifsnod, homename}, |
| 21 | mailnod = { &homenod, &ps1nod, mailname}; |
| 22 | |
| 23 | NAMPTR namep = &mailnod; |
| 24 | |
| 25 | |
| 26 | /* ======== variable and string handling ======== */ |
| 27 | |
| 28 | syslook(w,syswds) |
| 29 | STRING w; |
| 30 | SYSTAB syswds; |
| 31 | { |
| 32 | REG CHAR first; |
| 33 | REG STRING s; |
| 34 | REG SYSPTR syscan; |
| 35 | |
| 36 | syscan=syswds; first = *w; |
| 37 | |
| 38 | WHILE s=syscan->sysnam |
| 39 | DO IF first == *s |
| 40 | ANDF eq(w,s) |
| 41 | THEN return(syscan->sysval); |
| 42 | FI |
| 43 | syscan++; |
| 44 | OD |
| 45 | return(0); |
| 46 | } |
| 47 | |
| 48 | setlist(arg,xp) |
| 49 | REG ARGPTR arg; |
| 50 | INT xp; |
| 51 | { |
| 52 | WHILE arg |
| 53 | DO REG STRING s=mactrim(arg->argval); |
| 54 | setname(s, xp); |
| 55 | arg=arg->argnxt; |
| 56 | IF flags&execpr |
| 57 | THEN prs(s); |
| 58 | IF arg THEN blank(); ELSE newline(); FI |
| 59 | FI |
| 60 | OD |
| 61 | } |
| 62 | |
| 63 | VOID setname(argi, xp) |
| 64 | STRING argi; |
| 65 | INT xp; |
| 66 | { |
| 67 | REG STRING argscan=argi; |
| 68 | REG NAMPTR n; |
| 69 | |
| 70 | IF letter(*argscan) |
| 71 | THEN WHILE alphanum(*argscan) DO argscan++ OD |
| 72 | IF *argscan=='=' |
| 73 | THEN *argscan = 0; |
| 74 | n=lookup(argi); |
| 75 | *argscan++ = '='; |
| 76 | attrib(n, xp); |
| 77 | IF xp&N_ENVNAM |
| 78 | THEN n->namenv = n->namval = argscan; |
| 79 | ELSE assign(n, argscan); |
| 80 | FI |
| 81 | return; |
| 82 | FI |
| 83 | FI |
| 84 | failed(argi,notid); |
| 85 | } |
| 86 | |
| 87 | replace(a, v) |
| 88 | REG STRING *a; |
| 89 | STRING v; |
| 90 | { |
| 91 | free(*a); *a=make(v); |
| 92 | } |
| 93 | |
| 94 | dfault(n,v) |
| 95 | NAMPTR n; |
| 96 | STRING v; |
| 97 | { |
| 98 | IF n->namval==0 |
| 99 | THEN assign(n,v) |
| 100 | FI |
| 101 | } |
| 102 | |
| 103 | assign(n,v) |
| 104 | NAMPTR n; |
| 105 | STRING v; |
| 106 | { |
| 107 | IF n->namflg&N_RDONLY |
| 108 | THEN failed(n->namid,wtfailed); |
| 109 | ELSE replace(&n->namval,v); |
| 110 | FI |
| 111 | } |
| 112 | |
| 113 | INT readvar(names) |
| 114 | STRING *names; |
| 115 | { |
| 116 | FILEBLK fb; |
| 117 | REG FILE f = &fb; |
| 118 | REG CHAR c; |
| 119 | REG INT rc=0; |
| 120 | NAMPTR n=lookup(*names++); /* done now to avoid storage mess */ |
| 121 | STKPTR rel=relstak(); |
| 122 | |
| 123 | push(f); initf(dup(0)); |
| 124 | IF lseek(0,0L,1)==-1 |
| 125 | THEN f->fsiz=1; |
| 126 | FI |
| 127 | |
| 128 | LOOP c=nextc(0); |
| 129 | IF (*names ANDF any(c, ifsnod.namval)) ORF eolchar(c) |
| 130 | THEN zerostak(); |
| 131 | assign(n,absstak(rel)); setstak(rel); |
| 132 | IF *names |
| 133 | THEN n=lookup(*names++); |
| 134 | ELSE n=0; |
| 135 | FI |
| 136 | IF eolchar(c) |
| 137 | THEN break; |
| 138 | FI |
| 139 | ELSE pushstak(c); |
| 140 | FI |
| 141 | POOL |
| 142 | WHILE n |
| 143 | DO assign(n, nullstr); |
| 144 | IF *names THEN n=lookup(*names++); ELSE n=0; FI |
| 145 | OD |
| 146 | |
| 147 | IF eof THEN rc=1 FI |
| 148 | lseek(0, (long)(f->fnxt-f->fend), 1); |
| 149 | pop(); |
| 150 | return(rc); |
| 151 | } |
| 152 | |
| 153 | assnum(p, i) |
| 154 | STRING *p; |
| 155 | INT i; |
| 156 | { |
| 157 | itos(i); replace(p,numbuf); |
| 158 | } |
| 159 | |
| 160 | STRING make(v) |
| 161 | STRING v; |
| 162 | { |
| 163 | REG STRING p; |
| 164 | |
| 165 | IF v |
| 166 | THEN movstr(v,p=alloc(length(v))); |
| 167 | return(p); |
| 168 | ELSE return(0); |
| 169 | FI |
| 170 | } |
| 171 | |
| 172 | |
| 173 | NAMPTR lookup(nam) |
| 174 | REG STRING nam; |
| 175 | { |
| 176 | REG NAMPTR nscan=namep; |
| 177 | REG NAMPTR *prev; |
| 178 | INT LR; |
| 179 | |
| 180 | IF !chkid(nam) |
| 181 | THEN failed(nam,notid); |
| 182 | FI |
| 183 | WHILE nscan |
| 184 | DO IF (LR=cf(nam,nscan->namid))==0 |
| 185 | THEN return(nscan); |
| 186 | ELIF LR<0 |
| 187 | THEN prev = &(nscan->namlft); |
| 188 | ELSE prev = &(nscan->namrgt); |
| 189 | FI |
| 190 | nscan = *prev; |
| 191 | OD |
| 192 | |
| 193 | /* add name node */ |
| 194 | nscan=alloc(sizeof *nscan); |
| 195 | nscan->namlft=nscan->namrgt=NIL; |
| 196 | nscan->namid=make(nam); |
| 197 | nscan->namval=0; nscan->namflg=N_DEFAULT; nscan->namenv=0; |
| 198 | return(*prev = nscan); |
| 199 | } |
| 200 | |
| 201 | LOCAL BOOL chkid(nam) |
| 202 | STRING nam; |
| 203 | { |
| 204 | REG CHAR * cp=nam; |
| 205 | |
| 206 | IF !letter(*cp) |
| 207 | THEN return(FALSE); |
| 208 | ELSE WHILE *++cp |
| 209 | DO IF !alphanum(*cp) |
| 210 | THEN return(FALSE); |
| 211 | FI |
| 212 | OD |
| 213 | FI |
| 214 | return(TRUE); |
| 215 | } |
| 216 | |
| 217 | LOCAL VOID (*namfn)(); |
| 218 | namscan(fn) |
| 219 | VOID (*fn)(); |
| 220 | { |
| 221 | namfn=fn; |
| 222 | namwalk(namep); |
| 223 | } |
| 224 | |
| 225 | LOCAL VOID namwalk(np) |
| 226 | REG NAMPTR np; |
| 227 | { |
| 228 | IF np |
| 229 | THEN namwalk(np->namlft); |
| 230 | (*namfn)(np); |
| 231 | namwalk(np->namrgt); |
| 232 | FI |
| 233 | } |
| 234 | |
| 235 | VOID printnam(n) |
| 236 | NAMPTR n; |
| 237 | { |
| 238 | REG STRING s; |
| 239 | |
| 240 | sigchk(); |
| 241 | IF s=n->namval |
| 242 | THEN prs(n->namid); |
| 243 | prc('='); prs(s); |
| 244 | newline(); |
| 245 | FI |
| 246 | } |
| 247 | |
| 248 | LOCAL STRING staknam(n) |
| 249 | REG NAMPTR n; |
| 250 | { |
| 251 | REG STRING p; |
| 252 | |
| 253 | p=movstr(n->namid,staktop); |
| 254 | p=movstr("=",p); |
| 255 | p=movstr(n->namval,p); |
| 256 | return(getstak(p+1-ADR(stakbot))); |
| 257 | } |
| 258 | |
| 259 | VOID exname(n) |
| 260 | REG NAMPTR n; |
| 261 | { |
| 262 | IF n->namflg&N_EXPORT |
| 263 | THEN free(n->namenv); |
| 264 | n->namenv = make(n->namval); |
| 265 | ELSE free(n->namval); |
| 266 | n->namval = make(n->namenv); |
| 267 | FI |
| 268 | } |
| 269 | |
| 270 | VOID printflg(n) |
| 271 | REG NAMPTR n; |
| 272 | { |
| 273 | IF n->namflg&N_EXPORT |
| 274 | THEN prs(export); blank(); |
| 275 | FI |
| 276 | IF n->namflg&N_RDONLY |
| 277 | THEN prs(readonly); blank(); |
| 278 | FI |
| 279 | IF n->namflg&(N_EXPORT|N_RDONLY) |
| 280 | THEN prs(n->namid); newline(); |
| 281 | FI |
| 282 | } |
| 283 | |
| 284 | VOID getenv() |
| 285 | { |
| 286 | REG STRING *e=environ; |
| 287 | |
| 288 | WHILE *e |
| 289 | DO setname(*e++, N_ENVNAM) OD |
| 290 | } |
| 291 | |
| 292 | LOCAL INT namec; |
| 293 | |
| 294 | VOID countnam(n) |
| 295 | NAMPTR n; |
| 296 | { |
| 297 | namec++; |
| 298 | } |
| 299 | |
| 300 | LOCAL STRING *argnam; |
| 301 | |
| 302 | VOID pushnam(n) |
| 303 | NAMPTR n; |
| 304 | { |
| 305 | IF n->namval |
| 306 | THEN *argnam++ = staknam(n); |
| 307 | FI |
| 308 | } |
| 309 | |
| 310 | STRING *setenv() |
| 311 | { |
| 312 | REG STRING *er; |
| 313 | |
| 314 | namec=0; |
| 315 | namscan(countnam); |
| 316 | argnam = er = getstak(namec*BYTESPERWORD+BYTESPERWORD); |
| 317 | namscan(pushnam); |
| 318 | *argnam++ = 0; |
| 319 | return(er); |
| 320 | } |