Rev 5222 | Details | Compare with Previous | Last modification | View Log | RSS feed
Rev | Author | Line No. | Line |
---|---|---|---|
5222 | serge | 1 | /* input_file.c - Deal with Input Files - |
6324 | serge | 2 | Copyright (C) 1987-2015 Free Software Foundation, Inc. |
5222 | serge | 3 | |
4 | This file is part of GAS, the GNU Assembler. |
||
5 | |||
6 | GAS 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 3, or (at your option) |
||
9 | any later version. |
||
10 | |||
11 | GAS 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 GAS; see the file COPYING. If not, write to the Free |
||
18 | Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA |
||
19 | 02110-1301, USA. */ |
||
20 | |||
21 | /* Confines all details of reading source bytes to this module. |
||
22 | All O/S specific crocks should live here. |
||
23 | What we lose in "efficiency" we gain in modularity. |
||
24 | Note we don't need to #include the "as.h" file. No common coupling! */ |
||
25 | |||
26 | #include "as.h" |
||
27 | #include "input-file.h" |
||
28 | #include "safe-ctype.h" |
||
29 | |||
30 | /* This variable is non-zero if the file currently being read should be |
||
31 | preprocessed by app. It is zero if the file can be read straight in. */ |
||
32 | int preprocess = 0; |
||
33 | |||
34 | /* This code opens a file, then delivers BUFFER_SIZE character |
||
35 | chunks of the file on demand. |
||
36 | BUFFER_SIZE is supposed to be a number chosen for speed. |
||
37 | The caller only asks once what BUFFER_SIZE is, and asks before |
||
38 | the nature of the input files (if any) is known. */ |
||
39 | |||
40 | #define BUFFER_SIZE (32 * 1024) |
||
41 | |||
42 | /* We use static data: the data area is not sharable. */ |
||
43 | |||
44 | static FILE *f_in; |
||
45 | static char *file_name; |
||
46 | |||
47 | /* Struct for saving the state of this module for file includes. */ |
||
48 | struct saved_file |
||
49 | { |
||
50 | FILE * f_in; |
||
51 | char * file_name; |
||
52 | int preprocess; |
||
53 | char * app_save; |
||
54 | }; |
||
55 | |||
56 | /* These hooks accommodate most operating systems. */ |
||
57 | |||
58 | void |
||
59 | input_file_begin (void) |
||
60 | { |
||
61 | f_in = (FILE *) 0; |
||
62 | } |
||
63 | |||
64 | void |
||
65 | input_file_end (void) |
||
66 | { |
||
67 | } |
||
68 | |||
69 | /* Return BUFFER_SIZE. */ |
||
70 | size_t |
||
71 | input_file_buffer_size (void) |
||
72 | { |
||
73 | return (BUFFER_SIZE); |
||
74 | } |
||
75 | |||
76 | /* Push the state of our input, returning a pointer to saved info that |
||
77 | can be restored with input_file_pop (). */ |
||
78 | |||
79 | char * |
||
80 | input_file_push (void) |
||
81 | { |
||
6324 | serge | 82 | struct saved_file *saved; |
5222 | serge | 83 | |
84 | saved = (struct saved_file *) xmalloc (sizeof *saved); |
||
85 | |||
86 | saved->f_in = f_in; |
||
87 | saved->file_name = file_name; |
||
88 | saved->preprocess = preprocess; |
||
89 | if (preprocess) |
||
90 | saved->app_save = app_push (); |
||
91 | |||
92 | /* Initialize for new file. */ |
||
93 | input_file_begin (); |
||
94 | |||
95 | return (char *) saved; |
||
96 | } |
||
97 | |||
98 | void |
||
99 | input_file_pop (char *arg) |
||
100 | { |
||
6324 | serge | 101 | struct saved_file *saved = (struct saved_file *) arg; |
5222 | serge | 102 | |
103 | input_file_end (); /* Close out old file. */ |
||
104 | |||
105 | f_in = saved->f_in; |
||
106 | file_name = saved->file_name; |
||
107 | preprocess = saved->preprocess; |
||
108 | if (preprocess) |
||
109 | app_pop (saved->app_save); |
||
110 | |||
111 | free (arg); |
||
112 | } |
||
113 | |||
114 | void |
||
115 | input_file_open (char *filename, /* "" means use stdin. Must not be 0. */ |
||
116 | int pre) |
||
117 | { |
||
118 | int c; |
||
119 | char buf[80]; |
||
120 | |||
121 | preprocess = pre; |
||
122 | |||
123 | gas_assert (filename != 0); /* Filename may not be NULL. */ |
||
124 | if (filename[0]) |
||
125 | { |
||
126 | f_in = fopen (filename, FOPEN_RT); |
||
127 | file_name = filename; |
||
128 | } |
||
129 | else |
||
130 | { |
||
131 | /* Use stdin for the input file. */ |
||
132 | f_in = stdin; |
||
133 | /* For error messages. */ |
||
134 | file_name = _("{standard input}"); |
||
135 | } |
||
136 | |||
137 | if (f_in == NULL) |
||
138 | { |
||
139 | as_bad (_("can't open %s for reading: %s"), |
||
140 | file_name, xstrerror (errno)); |
||
141 | return; |
||
142 | } |
||
143 | |||
144 | c = getc (f_in); |
||
145 | |||
146 | if (ferror (f_in)) |
||
147 | { |
||
148 | as_bad (_("can't read from %s: %s"), |
||
149 | file_name, xstrerror (errno)); |
||
150 | |||
151 | fclose (f_in); |
||
152 | f_in = NULL; |
||
153 | return; |
||
154 | } |
||
155 | |||
156 | /* Check for an empty input file. */ |
||
157 | if (feof (f_in)) |
||
158 | { |
||
159 | fclose (f_in); |
||
160 | f_in = NULL; |
||
161 | return; |
||
162 | } |
||
163 | gas_assert (c != EOF); |
||
164 | |||
165 | if (c == '#') |
||
166 | { |
||
167 | /* Begins with comment, may not want to preprocess. */ |
||
168 | c = getc (f_in); |
||
169 | if (c == 'N') |
||
170 | { |
||
171 | if (fgets (buf, sizeof (buf), f_in) |
||
172 | && !strncmp (buf, "O_APP", 5) && ISSPACE (buf[5])) |
||
173 | preprocess = 0; |
||
174 | if (!strchr (buf, '\n')) |
||
175 | ungetc ('#', f_in); /* It was longer. */ |
||
176 | else |
||
177 | ungetc ('\n', f_in); |
||
178 | } |
||
179 | else if (c == 'A') |
||
180 | { |
||
181 | if (fgets (buf, sizeof (buf), f_in) |
||
182 | && !strncmp (buf, "PP", 2) && ISSPACE (buf[2])) |
||
183 | preprocess = 1; |
||
184 | if (!strchr (buf, '\n')) |
||
185 | ungetc ('#', f_in); |
||
186 | else |
||
187 | ungetc ('\n', f_in); |
||
188 | } |
||
189 | else if (c == '\n') |
||
190 | ungetc ('\n', f_in); |
||
191 | else |
||
192 | ungetc ('#', f_in); |
||
193 | } |
||
194 | else |
||
195 | ungetc (c, f_in); |
||
196 | } |
||
197 | |||
198 | /* Close input file. */ |
||
199 | |||
200 | void |
||
201 | input_file_close (void) |
||
202 | { |
||
203 | /* Don't close a null file pointer. */ |
||
204 | if (f_in != NULL) |
||
205 | fclose (f_in); |
||
206 | |||
207 | f_in = 0; |
||
208 | } |
||
209 | |||
210 | /* This function is passed to do_scrub_chars. */ |
||
211 | |||
212 | static size_t |
||
213 | input_file_get (char *buf, size_t buflen) |
||
214 | { |
||
215 | size_t size; |
||
216 | |||
217 | if (feof (f_in)) |
||
218 | return 0; |
||
219 | |||
220 | size = fread (buf, sizeof (char), buflen, f_in); |
||
221 | if (ferror (f_in)) |
||
222 | as_bad (_("can't read from %s: %s"), file_name, xstrerror (errno)); |
||
223 | return size; |
||
224 | } |
||
225 | |||
226 | /* Read a buffer from the input file. */ |
||
227 | |||
228 | char * |
||
229 | input_file_give_next_buffer (char *where /* Where to place 1st character of new buffer. */) |
||
230 | { |
||
231 | char *return_value; /* -> Last char of what we read, + 1. */ |
||
232 | size_t size; |
||
233 | |||
234 | if (f_in == (FILE *) 0) |
||
235 | return 0; |
||
236 | /* fflush (stdin); could be done here if you want to synchronise |
||
237 | stdin and stdout, for the case where our input file is stdin. |
||
238 | Since the assembler shouldn't do any output to stdout, we |
||
239 | don't bother to synch output and input. */ |
||
240 | if (preprocess) |
||
241 | size = do_scrub_chars (input_file_get, where, BUFFER_SIZE); |
||
242 | else |
||
243 | size = input_file_get (where, BUFFER_SIZE); |
||
244 | |||
245 | if (size) |
||
246 | return_value = where + size; |
||
247 | else |
||
248 | { |
||
249 | if (fclose (f_in)) |
||
250 | as_warn (_("can't close %s: %s"), file_name, xstrerror (errno)); |
||
251 | |||
252 | f_in = (FILE *) 0; |
||
253 | return_value = 0; |
||
254 | } |
||
255 | |||
256 | return return_value; |
||
257 | } |