projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 42d6e430 BJ |
1 | # |
| 2 | /* | |
| 3 | * UNIX shell | |
| 4 | * | |
| 5 | * S. R. Bourne | |
| 6 | * Bell Telephone Laboratories | |
| 7 | * | |
| 8 | */ | |
| 9 | ||
| 10 | #include "defs.h" | |
| 11 | #include "sym.h" | |
| 12 | ||
| 13 | ||
| 14 | /* ======== character handling for command lines ========*/ | |
| 15 | ||
| 16 | ||
| 17 | word() | |
| 18 | { | |
| 19 | REG CHAR c, d; | |
| 20 | REG CHAR *argp=locstak()+BYTESPERWORD; | |
| 21 | INT alpha=1; | |
| 22 | ||
| 23 | wdnum=0; wdset=0; | |
| 24 | ||
| 25 | WHILE (c=nextc(0), space(c)) DONE | |
| 26 | IF !eofmeta(c) | |
| 27 | THEN REP IF c==LITERAL | |
| 28 | THEN *argp++=(DQUOTE); | |
| 29 | WHILE (c=readc()) ANDF c!=LITERAL | |
| 30 | DO *argp++=(c|QUOTE); chkpr(c) OD | |
| 31 | *argp++=(DQUOTE); | |
| 32 | ELSE *argp++=(c); | |
| 33 | IF c=='=' THEN wdset |= alpha FI | |
| 34 | IF !alphanum(c) THEN alpha=0 FI | |
| 35 | IF qotchar(c) | |
| 36 | THEN d=c; | |
| 37 | WHILE (*argp++=(c=nextc(d))) ANDF c!=d | |
| 38 | DO chkpr(c) OD | |
| 39 | FI | |
| 40 | FI | |
| 41 | PER (c=nextc(0), !eofmeta(c)) DONE | |
| 42 | argp=endstak(argp); | |
| 43 | IF !letter(argp->argval[0]) THEN wdset=0 FI | |
| 44 | ||
| 45 | peekc=c|MARK; | |
| 46 | IF argp->argval[1]==0 ANDF (d=argp->argval[0], digit(d)) ANDF (c=='>' ORF c=='<') | |
| 47 | THEN word(); wdnum=d-'0'; | |
| 48 | ELSE /*check for reserved words*/ | |
| 49 | IF reserv==FALSE ORF (wdval=syslook(argp->argval,reserved))==0 | |
| 50 | THEN wdarg=argp; wdval=0; | |
| 51 | FI | |
| 52 | FI | |
| 53 | ||
| 54 | ELIF dipchar(c) | |
| 55 | THEN IF (d=nextc(0))==c | |
| 56 | THEN wdval = c|SYMREP; | |
| 57 | ELSE peekc = d|MARK; wdval = c; | |
| 58 | FI | |
| 59 | ELSE IF (wdval=c)==EOF | |
| 60 | THEN wdval=EOFSYM; | |
| 61 | FI | |
| 62 | IF iopend ANDF eolchar(c) | |
| 63 | THEN copy(iopend); iopend=0; | |
| 64 | FI | |
| 65 | FI | |
| 66 | reserv=FALSE; | |
| 67 | return(wdval); | |
| 68 | } | |
| 69 | ||
| 70 | nextc(quote) | |
| 71 | CHAR quote; | |
| 72 | { | |
| 73 | REG CHAR c, d; | |
| 74 | IF (d=readc())==ESCAPE | |
| 75 | THEN IF (c=readc())==NL | |
| 76 | THEN chkpr(NL); d=nextc(quote); | |
| 77 | ELIF quote ANDF c!=quote ANDF !escchar(c) | |
| 78 | THEN peekc=c|MARK; | |
| 79 | ELSE d = c|QUOTE; | |
| 80 | FI | |
| 81 | FI | |
| 82 | return(d); | |
| 83 | } | |
| 84 | ||
| 85 | readc() | |
| 86 | { | |
| 87 | REG CHAR c; | |
| 88 | REG INT len; | |
| 89 | REG FILE f; | |
| 90 | ||
| 91 | retry: | |
| 92 | IF peekc | |
| 93 | THEN c=peekc; peekc=0; | |
| 94 | ELIF (f=standin, f->fnxt!=f->fend) | |
| 95 | THEN IF (c = *f->fnxt++)==0 | |
| 96 | THEN IF f->feval | |
| 97 | THEN IF estabf(*f->feval++) | |
| 98 | THEN c=EOF; | |
| 99 | ELSE c=SP; | |
| 100 | FI | |
| 101 | ELSE goto retry; /* = c=readc(); */ | |
| 102 | FI | |
| 103 | FI | |
| 104 | IF flags&readpr ANDF standin->fstak==0 THEN prc(c) FI | |
| 105 | IF c==NL THEN f->flin++ FI | |
| 106 | ELIF f->feof ORF f->fdes<0 | |
| 107 | THEN c=EOF; f->feof++; | |
| 108 | ELIF (len=readb())<=0 | |
| 109 | THEN close(f->fdes); f->fdes = -1; c=EOF; f->feof++; | |
| 110 | ELSE f->fend = (f->fnxt = f->fbuf)+len; | |
| 111 | goto retry; | |
| 112 | FI | |
| 113 | return(c); | |
| 114 | } | |
| 115 | ||
| 116 | LOCAL readb() | |
| 117 | { | |
| 118 | REG FILE f=standin; | |
| 119 | REG INT len; | |
| 120 | ||
| 121 | REP IF trapnote&SIGSET THEN newline(); sigchk() FI | |
| 122 | PER (len=read(f->fdes,f->fbuf,f->fsiz))<0 ANDF trapnote DONE | |
| 123 | return(len); | |
| 124 | } |