When scanning MS import libraries allow for the possible presence of static
[binutils.git] / gas / input-file.c
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1 /* input_file.c - Deal with Input Files -
2 Copyright 1987, 1990, 1991, 1992, 1993, 1994, 1995, 1999, 2000, 2001, 2003
3 Free Software Foundation, Inc.
5 This file is part of GAS, the GNU Assembler.
7 GAS is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
10 any later version.
12 GAS is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GAS; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
20 02111-1307, USA. */
22 /* Confines all details of reading source bytes to this module.
23 All O/S specific crocks should live here.
24 What we lose in "efficiency" we gain in modularity.
25 Note we don't need to #include the "as.h" file. No common coupling! */
27 #include <stdio.h>
28 #include <string.h>
29 #include <sys/stat.h>
30 #include "as.h"
31 #include "input-file.h"
32 #include "safe-ctype.h"
34 static int input_file_get (char *, int);
36 /* This variable is non-zero if the file currently being read should be
37 preprocessed by app. It is zero if the file can be read straight in. */
38 int preprocess = 0;
40 /* This code opens a file, then delivers BUFFER_SIZE character
41 chunks of the file on demand.
42 BUFFER_SIZE is supposed to be a number chosen for speed.
43 The caller only asks once what BUFFER_SIZE is, and asks before
44 the nature of the input files (if any) is known. */
46 #define BUFFER_SIZE (32 * 1024)
48 /* We use static data: the data area is not sharable. */
50 static FILE *f_in;
51 static char *file_name;
53 /* Struct for saving the state of this module for file includes. */
54 struct saved_file
56 FILE * f_in;
57 char * file_name;
58 int preprocess;
59 char * app_save;
62 /* These hooks accommodate most operating systems. */
64 void
65 input_file_begin (void)
67 f_in = (FILE *) 0;
70 void
71 input_file_end (void)
75 /* Return BUFFER_SIZE. */
76 unsigned int
77 input_file_buffer_size (void)
79 return (BUFFER_SIZE);
82 int
83 input_file_is_open (void)
85 return f_in != (FILE *) 0;
88 /* Push the state of our input, returning a pointer to saved info that
89 can be restored with input_file_pop (). */
91 char *
92 input_file_push (void)
94 register struct saved_file *saved;
96 saved = (struct saved_file *) xmalloc (sizeof *saved);
98 saved->f_in = f_in;
99 saved->file_name = file_name;
100 saved->preprocess = preprocess;
101 if (preprocess)
102 saved->app_save = app_push ();
104 /* Initialize for new file. */
105 input_file_begin ();
107 return (char *) saved;
110 void
111 input_file_pop (char *arg)
113 register struct saved_file *saved = (struct saved_file *) arg;
115 input_file_end (); /* Close out old file. */
117 f_in = saved->f_in;
118 file_name = saved->file_name;
119 preprocess = saved->preprocess;
120 if (preprocess)
121 app_pop (saved->app_save);
123 free (arg);
126 void
127 input_file_open (char *filename, /* "" means use stdin. Must not be 0. */
128 int pre)
130 int c;
131 char buf[80];
133 preprocess = pre;
135 assert (filename != 0); /* Filename may not be NULL. */
136 if (filename[0])
138 struct stat statbuf;
140 if (stat (filename, &statbuf) < 0)
142 as_bad (_("%s: No such file"), filename);
143 return;
145 else if (! S_ISREG (statbuf.st_mode))
147 as_bad (_("'%s' is not an ordinary file"), filename);
148 return;
151 f_in = fopen (filename, FOPEN_RT);
152 file_name = filename;
154 else
156 /* Use stdin for the input file. */
157 f_in = stdin;
158 /* For error messages. */
159 file_name = _("{standard input}");
162 if (f_in == (FILE *) 0)
164 as_bad (_("can't open %s for reading"), file_name);
165 as_perror ("%s", file_name);
166 return;
169 c = getc (f_in);
170 if (c == '#')
172 /* Begins with comment, may not want to preprocess. */
173 c = getc (f_in);
174 if (c == 'N')
176 fgets (buf, 80, f_in);
177 if (!strncmp (buf, "O_APP", 5) && ISSPACE (buf[5]))
178 preprocess = 0;
179 if (!strchr (buf, '\n'))
180 ungetc ('#', f_in); /* It was longer. */
181 else
182 ungetc ('\n', f_in);
184 else if (c == 'A')
186 fgets (buf, 80, f_in);
187 if (!strncmp (buf, "PP", 2) && ISSPACE (buf[2]))
188 preprocess = 1;
189 if (!strchr (buf, '\n'))
190 ungetc ('#', f_in);
191 else
192 ungetc ('\n', f_in);
194 else if (c == '\n')
195 ungetc ('\n', f_in);
196 else
197 ungetc ('#', f_in);
199 else
200 ungetc (c, f_in);
203 /* Close input file. */
205 void
206 input_file_close (void)
208 /* Don't close a null file pointer. */
209 if (f_in != NULL)
210 fclose (f_in);
212 f_in = 0;
215 /* This function is passed to do_scrub_chars. */
217 static int
218 input_file_get (char *buf, int buflen)
220 int size;
222 size = fread (buf, sizeof (char), buflen, f_in);
223 if (size < 0)
225 as_perror (_("Can't read from %s"), file_name);
226 size = 0;
228 return size;
231 /* Read a buffer from the input file. */
233 char *
234 input_file_give_next_buffer (char *where /* Where to place 1st character of new buffer. */)
236 char *return_value; /* -> Last char of what we read, + 1. */
237 register int size;
239 if (f_in == (FILE *) 0)
240 return 0;
241 /* fflush (stdin); could be done here if you want to synchronise
242 stdin and stdout, for the case where our input file is stdin.
243 Since the assembler shouldn't do any output to stdout, we
244 don't bother to synch output and input. */
245 if (preprocess)
246 size = do_scrub_chars (input_file_get, where, BUFFER_SIZE);
247 else
248 size = fread (where, sizeof (char), BUFFER_SIZE, f_in);
249 if (size < 0)
251 as_perror (_("Can't read from %s"), file_name);
252 size = 0;
254 if (size)
255 return_value = where + size;
256 else
258 if (fclose (f_in))
259 as_perror (_("Can't close %s"), file_name);
260 f_in = (FILE *) 0;
261 return_value = 0;
264 return return_value;