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1.1 root 1: #include <stdio.h>
2: #include "typedef.h"
3: #include "basic.h"
4: #include "tokens.h"
5: #include <signal.h>
6:
7: #define SEEK_EOF 2
8: #define MAGIC 2249413169 /* magic number for image files */
9:
10: char *prompt = ">"; /* the prompt charcter */
11: int col = 1; /* current output column */
12: static int symsize = MAXSYMSPACE; /* size of symbol table */
13:
14: FILE *xopen();
15: char *sbrk(), *endstr();
16: void fpterr(), attn();
17: double fabs();
18: long ftell();
19:
20:
21: /*
22: * initsys --- perfor system-dependent initialization
23: */
24:
25: initsys()
26: {
27:
28: infile = stdin;
29: tty = isatty(fileno(stdin));
30: signal(SIGFPE, fpterr);
31: signal(SIGINT, attn);
32: lines = sbrk(MAXLINES + MAXSYMSPACE); /* base of line buffer */
33: endlines = lines + MAXSYMSPACE;
34: symspace = endlines; /* start of symbol table */
35: symend = sbrk(0);
36: if ((int)lines == -1)
37: error("unable to allocate initial space");
38: initio();
39: }
40:
41:
42: /*
43: * attn --- function invoked upon SIGINT
44: */
45:
46: void attn()
47: {
48:
49: signal(SIGINT, attn);
50: if (attnflg++)
51: err("attn!");
52: }
53:
54:
55: /*
56: * readline --- get a newline-terminated line from specified file
57: */
58:
59: readline(linep, inf)
60: char *linep;
61: FILE *inf;
62: {
63: register int c;
64: register char *p;
65:
66: for (p = linep; (c = getc(inf)) >= 0 ; ) {
67: if (c == '\r' || c == 0)
68: ;
69: else if (c == '\n') {
70: *p = 0;
71: if (inf == stdin)
72: col = 1;
73: return(p - linep);
74: }
75: else {
76: if (inf == stdin)
77: ++col;
78: if (p >= linep + MAXLINELEN)
79: err("line too long");
80: *p++ = c;
81: }
82: }
83: return(-1);
84: }
85:
86:
87: /*
88: * syserr --- do system-dependent error handling
89: */
90:
91: syserr()
92: {
93:
94: fseek(infile, 0L, SEEK_EOF); /* in case input is a file */
95: if (infile != stdin) { /* reset input to stdin */
96: xclose(infile);
97: infile = stdin;
98: }
99: }
100:
101:
102: /*
103: * error --- print an error message and exit
104: */
105:
106: error(fmt, d1, d2, d3)
107: {
108:
109: fprintf(stderr, fmt, d1, d2, d3);
110: exit(1);
111: }
112:
113:
114: /*
115: * err --- print an error message and jump back to main program
116: */
117:
118: err(fmt, d1, d2, d3)
119: {
120:
121: fprintf(stderr, fmt, d1, d2, d3);
122: if (curline != (Linep)NULL && curline != &immed)
123: fprintf(stderr, " at line %u", curline->l_lnr);
124: putc('\n', stderr);
125: attnflg = 0;
126: syserr();
127: leave(fmt);
128: exit(1);
129: }
130:
131:
132: /*
133: * fpterr --- function invoked upon SIGFPE
134: */
135:
136: void fpterr()
137: {
138:
139: signal(SIGFPE, fpterr);
140: err("floating point error");
141: }
142:
143:
144: /*
145: * fprint --- convert floating point to string
146: */
147:
148: char *fprint(f)
149: double f;
150: {
151: register char *s;
152: static char fpbuff[30];
153: double e;
154: int decpt, sign;
155:
156: #define MINF 0.00000001
157: #define MAXF 10000000.0
158: #define NDIGITS 5
159:
160: e = fabs(f);
161: if (e > MAXF || (e != 0.0 && e < MINF))
162: ftoa(f, fpbuff, NDIGITS, 'e');
163: else
164: ftoa(f, fpbuff, NDIGITS, 'f');
165: return(fpbuff);
166: }
167:
168:
169: /*
170: * ftoa --- do the real work for fprint
171: */
172:
173: ftoa(f, ptr, ndig, format)
174: double f;
175: char *ptr;
176: {
177: register char *s;
178:
179: if (format == 'e')
180: sprintf(ptr, "%.*e", ndig, f);
181: else {
182: sprintf(ptr, "%.*f", ndig, f);
183: s = endstr(ptr);
184: while (*--s == '0')
185: ;
186: if (*s == '.')
187: --s;
188: s[1] = 0;
189: }
190: }
191:
192:
193: /*
194: * morelines --- try to allocate more space for line storage
195: */
196:
197: morelines()
198: {
199: register char *p;
200:
201: p = endlines + EXPANDLINES;
202: if ((int)sbrk(EXPANDLINES) == -1)
203: return(NO);
204: endlines = p;
205: symspace = endlines;
206: symend = symspace + symsize;
207: clrsym();
208: return(YES);
209: }
210:
211:
212: /*
213: * moresym --- try to allocate more space for the symbol table
214: */
215:
216: moresym(p)
217: char *p;
218: {
219: register int n;
220:
221: n = p - symend;
222: n = (n + EXPANDSYM - 1) & ~(EXPANDSYM - 1); /* make it even */
223: if (p < symend || (int)sbrk(n) == -1)
224: return(NO);
225: symend += n;
226: symsize = symend - symspace;
227: return(YES);
228: }
229:
230:
231: /*
232: * old --- read a program from the file with specified name
233: */
234:
235: void old(file)
236: char *file;
237: {
238: register FILE *i, *oldfile;
239:
240: if (*file == 0)
241: err("file name expected");
242: if ((i = xopen(file, "r")) == (FILE *)NULL)
243: err("can't open %s", file);
244: if (file != tempfile)
245: strcpy(curfile, file); /* save current file name */
246: init();
247: oldfile = infile;
248: infile = i;
249: if (readline(line, infile) > 0 && fastload(line, infile) == NO) {
250: compile();
251: while (readline(line, infile) > 0)
252: compile();
253: }
254: xclose(infile);
255: infile = oldfile;
256: }
257:
258:
259: /*
260: * fastload --- try to load a program image from the specified file
261: */
262:
263: fastload(lp, file)
264: register char *lp;
265: FILE *file;
266: {
267: int magic, bcount, nlines, check;
268:
269: if (sscanf(lp, "#%d %d %d %d\n", &magic, &bcount, &nlines, &check) != 4
270: || magic != MAGIC
271: || (magic ^ bcount ^ nlines ^ check))
272: return(NO);
273: while (endlines - lines < bcount && morelines())
274: ;
275: if (bcount > endlines - lines)
276: err("program image too big");
277: lastline = lines + bcount;
278: linecnt = nlines;
279: lseek(fileno(file), ftell(file), 0);
280: if (read(fileno(file), lines, bcount) != bcount)
281: err("error in loading program image");
282: return(YES);
283: }
284:
285:
286: /*
287: * save --- write the program onto the named file
288: */
289:
290: save(file)
291: char *file;
292: {
293: register FILE *f;
294: int i, j;
295:
296: for (i = j = 0; file[i] != '\0'; i++)
297: if (file[i] != ' ')
298: file[j++] = file[i];
299: file[j] = '\0';
300:
301: /* remove the blanks from the name */
302:
303:
304: if (file[0] == 0 || (f = xopen(file, "w")) == (FILE *)NULL)
305: err("can't create file %s", file);
306: inptr = endstr(inptr);
307: list(MINLNR, MAXLNR, f);
308: xclose(f);
309: }
310:
311:
312: /*
313: * fastsave --- write a program image to the named file
314: */
315:
316: fastsave(file)
317: char *file;
318: {
319: register FILE *f;
320: register int check, bcount;
321:
322: if (file[0] == 0 || (f = xopen(file, "w")) == (FILE *)NULL)
323: err("can't create file %s", file);
324: inptr = endstr(inptr);
325: bcount = lastline - lines;
326: check = MAGIC ^ bcount ^ linecnt;
327: fprintf(f, "#%u %u %u %u\n", MAGIC, bcount, linecnt, check);
328: fflush(f);
329: if (write(fileno(f), lines, bcount) != bcount)
330: err("error in writing program image");
331: xclose(f);
332: }
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