1 /* main.c: The main program for bc. */
2
3 /* This file is part of bc written for MINIX.
4 Copyright (C) 1991, 1992 Free Software Foundation, Inc.
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License , or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; see the file COPYING. If not, write to
18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
19
20 You may contact the author by:
21 e-mail: phil@cs.wwu.edu
22 us-mail: Philip A. Nelson
23 Computer Science Department, 9062
24 Western Washington University
25 Bellingham, WA 98226-9062
26
27 *************************************************************************/
28
29 #include "bcdefs.h"
30 #include <signal.h>
31 #include "global.h"
32 #include "proto.h"
33
34 /* Variables for processing multiple files. */
35 char first_file;
36 extern FILE *yyin;
37
38
39 /* The main program for bc. */
40 int
main(argc,argv)41 main (argc, argv)
42 int argc;
43 char *argv[];
44 {
45 int ch;
46
47 /* Initialize many variables. */
48 compile_only = FALSE;
49 use_math = FALSE;
50 warn_not_std = FALSE;
51 std_only = FALSE;
52 if (isatty(0) && isatty(1))
53 interactive = TRUE;
54 else
55 interactive = FALSE;
56
57 /* Parse the command line */
58 ch = getopt (argc, argv, "lcisvw");
59 while (ch != EOF)
60 {
61 switch (ch)
62 {
63 case 'c': /* compile only */
64 compile_only = TRUE;
65 break;
66 case 'l': /* math lib */
67 use_math = TRUE;
68 break;
69 case 'i': /* force interactive */
70 interactive = TRUE;
71 break;
72 case 'w': /* Non standard features give warnings. */
73 warn_not_std = TRUE;
74 break;
75 case 's': /* Non standard features give errors. */
76 std_only = TRUE;
77 break;
78 case 'v': /* Print the version. */
79 printf ("%s\n", BC_VERSION);
80 break;
81 }
82 ch = getopt (argc, argv, "lcisvw");
83 }
84
85 /* Initialize the machine. */
86 init_storage();
87 init_load();
88
89 /* Set up interrupts to print a message. */
90 if (interactive)
91 signal (SIGINT, use_quit);
92
93 /* Initialize the front end. */
94 init_tree();
95 init_gen ();
96 g_argv = argv;
97 g_argc = argc;
98 is_std_in = FALSE;
99 first_file = TRUE;
100 if (!open_new_file ())
101 exit (1);
102
103 /* Do the parse. */
104 yyparse ();
105
106 /* End the compile only output with a newline. */
107 if (compile_only)
108 printf ("\n");
109
110 exit (0);
111 }
112
113
114 /* This is the function that opens all the files.
115 It returns TRUE if the file was opened, otherwise
116 it returns FALSE. */
117
118 int
open_new_file()119 open_new_file ()
120 {
121 FILE *new_file;
122
123 /* Set the line number. */
124 line_no = 1;
125
126 /* Check to see if we are done. */
127 if (is_std_in) return (FALSE);
128
129 /* Open the other files. */
130 if (use_math && first_file)
131 {
132 #ifdef BC_MATH_FILE
133 /* Make the first file be the math library. */
134 new_file = fopen (BC_MATH_FILE, "r");
135 use_math = FALSE;
136 if (new_file != NULL)
137 {
138 new_yy_file (new_file);
139 return TRUE;
140 }
141 else
142 {
143 fprintf (stderr, "Math Library unavailable.\n");
144 exit (1);
145 }
146 #else
147 /* Load the code from a precompiled version of the math libarary. */
148 extern char libmath[];
149 char tmp;
150 /* These MUST be in the order of first mention of each function.
151 That is why "a" comes before "c" even though "a" is defined after
152 after "c". "a" is used in "s"! */
153 tmp = lookup ("e", FUNCT);
154 tmp = lookup ("l", FUNCT);
155 tmp = lookup ("s", FUNCT);
156 tmp = lookup ("a", FUNCT);
157 tmp = lookup ("c", FUNCT);
158 tmp = lookup ("j", FUNCT);
159 load_code (libmath);
160 #endif
161 }
162
163 /* One of the argv values. */
164 while (optind < g_argc)
165 {
166 new_file = fopen (g_argv[optind], "r");
167 if (new_file != NULL)
168 {
169 new_yy_file (new_file);
170 optind++;
171 return TRUE;
172 }
173 fprintf (stderr, "File %s is unavailable.\n", g_argv[optind++]);
174 exit (1);
175 }
176
177 /* If we fall through to here, we should return stdin. */
178 new_yy_file (stdin);
179 is_std_in = TRUE;
180 return TRUE;
181 }
182
183
184 /* Set yyin to the new file. */
185
186 void
new_yy_file(file)187 new_yy_file (file)
188 FILE *file;
189 {
190 if (!first_file) fclose (yyin);
191 yyin = file;
192 first_file = FALSE;
193 }
194
195
196 /* Message to use quit. */
197
198 void
use_quit(sig)199 use_quit (sig)
200 int sig;
201 {
202 printf ("\n(interrupt) use quit to exit.\n");
203 signal (SIGINT, use_quit);
204 }
205