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1.1 root 1: #include "e.h"
2: #include "e.def"
3:
4: #define SSIZE 400
5: char token[SSIZE];
6: int sp;
7: #define putbak(c) *ip++ = c;
8: #define PUSHBACK 300 /* maximum pushback characters */
9: char ibuf[PUSHBACK+SSIZE]; /* pushback buffer for definitions, etc. */
10: char *ip = ibuf;
11:
12: gtc() {
13: loop:
14: if (ip > ibuf)
15: return(*--ip); /* already present */
16: lastchar = getc(curfile);
17: if (lastchar=='\n')
18: linect++;
19: if (lastchar != EOF)
20: return(lastchar);
21: if (++ifile > svargc) {
22: return(EOF);
23: }
24: fclose(curfile);
25: linect = 1;
26: if ((curfile=fopen(svargv[ifile], "r")) != NULL)
27: goto loop;
28: error(FATAL, "can't open file %s", svargv[ifile]);
29: return(EOF);
30: }
31:
32: pbstr(str)
33: register char *str;
34: {
35: register char *p;
36:
37: p = str;
38: while (*p++);
39: --p;
40: if (ip >= &ibuf[PUSHBACK])
41: error( FATAL, "pushback overflow");
42: while (p > str)
43: putbak(*--p);
44: }
45:
46: yylex() {
47: register int c;
48: tbl *tp, *lookup();
49: extern tbl **keytbl, **deftbl;
50:
51: beg:
52: while ((c=gtc())==' ' || c=='\n')
53: ;
54: yylval=c;
55: switch(c) {
56:
57: case EOF:
58: return(EOF);
59: case '~':
60: return(SPACE);
61: case '^':
62: return(THIN);
63: case '\t':
64: return(TAB);
65: case '{':
66: return('{');
67: case '}':
68: return('}');
69: case '"':
70: for (sp=0; (c=gtc())!='"' && c != '\n'; ) {
71: if (c == '\\')
72: if ((c = gtc()) != '"')
73: token[sp++] = '\\';
74: token[sp++] = c;
75: if (sp>=SSIZE)
76: error(FATAL, "quoted string %.20s... too long", token);
77: }
78: token[sp]='\0';
79: yylval = (int) &token[0];
80: if (c == '\n')
81: error(!FATAL, "missing \" in %.20s", token);
82: return(QTEXT);
83: }
84: if (c==righteq)
85: return(EOF);
86:
87: putbak(c);
88: getstr(token, SSIZE);
89: if (dbg)printf(".\tlex token = |%s|\n", token);
90: if ((tp = lookup(&deftbl, token, NULL)) != NULL) {
91: putbak(' ');
92: pbstr(tp->defn);
93: putbak(' ');
94: if (dbg)
95: printf(".\tfound %s|=%s|\n", token, tp->defn);
96: }
97: else if ((tp = lookup(&keytbl, token, NULL)) == NULL) {
98: if(dbg)printf(".\t%s is not a keyword\n", token);
99: return(CONTIG);
100: }
101: else if (tp->defn == (char *) DEFINE || tp->defn == (char *) NDEFINE || tp->defn == (char *) TDEFINE)
102: define(tp->defn);
103: else if (tp->defn == (char *) DELIM)
104: delim();
105: else if (tp->defn == (char *) GSIZE)
106: globsize();
107: else if (tp->defn == (char *) GFONT)
108: globfont();
109: else if (tp->defn == (char *) INCLUDE)
110: include();
111: else {
112: return((int) tp->defn);
113: }
114: goto beg;
115: }
116:
117: getstr(s, n) char *s; register int n; {
118: register int c;
119: register char *p;
120:
121: p = s;
122: while ((c = gtc()) == ' ' || c == '\n')
123: ;
124: if (c == EOF) {
125: *s = 0;
126: return;
127: }
128: while (c != ' ' && c != '\t' && c != '\n' && c != '{' && c != '}'
129: && c != '"' && c != '~' && c != '^' && c != righteq) {
130: if (c == '\\')
131: if ((c = gtc()) != '"')
132: *p++ = '\\';
133: *p++ = c;
134: if (--n <= 0)
135: error(FATAL, "token %.20s... too long", s);
136: c = gtc();
137: }
138: if (c=='{' || c=='}' || c=='"' || c=='~' || c=='^' || c=='\t' || c==righteq)
139: putbak(c);
140: *p = '\0';
141: yylval = (int) s;
142: }
143:
144: cstr(s, quote, maxs) char *s; int quote; {
145: int del, c, i;
146:
147: while((del=gtc()) == ' ' || del == '\t' || del == '\n');
148: if (quote)
149: for (i=0; (c=gtc()) != del && c != EOF;) {
150: s[i++] = c;
151: if (i >= maxs)
152: return(1); /* disaster */
153: }
154: else {
155: s[0] = del;
156: for (i=1; (c=gtc())!=' ' && c!= '\t' && c!='\n' && c!=EOF;) {
157: s[i++]=c;
158: if (i >= maxs)
159: return(1); /* disaster */
160: }
161: }
162: s[i] = '\0';
163: if (c == EOF)
164: error(FATAL, "Unexpected end of input at %.20s", s);
165: return(0);
166: }
167:
168: define(type) int type; {
169: char *strsave(), *p1, *p2;
170: tbl *lookup();
171: extern tbl **deftbl;
172:
173: getstr(token, SSIZE); /* get name */
174: if (type != DEFINE) {
175: cstr(token, 1, SSIZE); /* skip the definition too */
176: return;
177: }
178: p1 = strsave(token);
179: if (cstr(token, 1, SSIZE))
180: error(FATAL, "Unterminated definition at %.20s", token);
181: p2 = strsave(token);
182: lookup(&deftbl, p1, p2);
183: if (dbg)printf(".\tname %s defined as %s\n", p1, p2);
184: }
185:
186: char *strsave(s)
187: char *s;
188: {
189: char *malloc();
190: register char *q;
191:
192: q = malloc(strlen(s)+1);
193: if (q == NULL)
194: error(FATAL, "out of space in strsave on %s", s);
195: strcpy(q, s);
196: return(q);
197: }
198:
199: include() {
200: error(!FATAL, "Include not yet implemented");
201: }
202:
203: delim() {
204: yyval = eqnreg = 0;
205: if (cstr(token, 0, SSIZE))
206: error(FATAL, "Bizarre delimiters at %.20s", token);
207: lefteq = token[0];
208: righteq = token[1];
209: if (lefteq == 'o' && righteq == 'f')
210: lefteq = righteq = '\0';
211: }
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